Deck 1 Flashcards

Question

A 30 year old women is involved in a road traffic accident she is a passenger in a car involved in a head on collision with another vehicle. Her car is travelling at 60mph. She has been haemodynamically stable throughout with only minimal tachycardia. On examination she has marked abdominal tenderness and a large amount of intra abdominal fluid on CT scan ``` A. Tension pneumothorax B. Haemopericardium C. Haemothorax D. Aortic transection E. Ruptured spleen F. Duodeno-jejunal flexure disruption G. Aorto iliac disruption H. Ileo-colic junction disruption ```

Answer 1

Duodeno-jejunal flexure disruption This is another site of sudden deceleration injury. Given the large amount of free fluid, if it were blood, then a greater degree of haemodynamic instability would be expected.

Answer 2

Haemopericardium This is most likely a cardiac tamponade produced by haemopericardium. As little as 100ml of blood may result in tamponade as the pericardial sac is not distensible. Diagnosis is suggested by muffled heart sounds, paradoxical pulse and jugular vein distension.

Answer 3

Damage to sweat glands Partial thickness burns are divided into superficial and deep burns, however, this is often not possible on initial assessment and it may be a week or more before the distinction is clear cut. Dermal appendages are, by definition, intact. Superficial partial thickness burns will typically heal by re-epithelialisation, deeper burns will heal with scarring. Burns may be thermal, chemical or electrical. In the former category are burns which occur as a result of heat. Chemical burns occur when the skin is exposed to an extremely caustic or alkaline substance. Electrical burns occur following exposure to electrical current. The immediate management includes removal of the burning source which usually includes irrigation of the burned area. A detailed assessment then needs to be made of the extent of the burns and a number of charts are available for recording this information. The degree of injury relates to the temperature and duration of exposure. Most domestic burns are mainly scalds in young children. Following the burn, there is a local response with progressive tissue loss and release of inflammatory cytokines. Systemically, there are cardiovascular effects resulting from fluid loss and sequestration of fluid into the third space. There is a marked catabolic response. Immunosupression is common with large burns and bacterial translocation from the gut lumen is a recognised event. Sepsis is a common cause of death following major burns. Management The initial aim is to stop the burning process and resuscitate the patient. Intravenous fluids will be required for children with burns greater than 10% of total body surface area. Adults with burns greater than 15% of total body surface area will also require IV fluids. The fluids are calculated using the Parkland formula which is; volume of fluid= total body surface area of the burn % x weight (Kg) x4. Half of the fluid is administered in the first 8 hours. A urinary catheter should be inserted. Analgesia should be given. Complex burns, burns involving the hand perineum and face and burns >10% in adults and >5% in children should be transferred to a burns unit. Circumferential burns affecting a limb or severe torso burns impeding respiration may require escharotomy to divide the burnt tissue. Conservative management is appropriate for superficial burns and mixed superficial burns that will heal in 2 weeks. More complex burns may require excision and skin grafting. Excision and primary closure is not generally practised as there is a high risk of infection. There is no evidence to support the use of anti microbial prophylaxis or topical antibiotics in burn patients. Escharotomies Indicated in circumferential full thickness burns to the torso or limbs. Careful division of the encasing band of burn tissue will potentially improve ventilation (if the burn involves the torso), or relieve compartment syndrome and oedema (where a limb is involved)

Answer 4

Opiates should be avoided Head injury management- NICE Guidelines Summary of guidelines All patients should be assessed within 15 minutes on arrival to A&E Document all 3 components of the GCS If GCS <8 or = to 8, consider stabilising the airway Treat pain with low dose IV opiates (if safe) Full spine immobilisation until assessment if: - GCS < 15 - neck pain/tenderness - paraesthesia extremities - focal neurological deficit - suspected c-spine injury If a c-spine injury is suspected a 3 view c-spine x-ray is indicated. CT c-spine is preferred if: - Intubated - GCS <13 - Normal x-ray but continued concerns regarding c-spine injury - Any focal neurology - A CT head scan is being performed - Initial plain films are abnormal ``` Immediate CT head (within 1 hour) if: GCS < 13 on admission GCS < 15 2 hours after admission Suspected open or depressed skull fracture Suspected skull base fracture (panda eyes, Battle's sign, CSF from nose/ear, bleeding ear) Focal neurology Vomiting > 1 episode Post traumatic seizure Coagulopathy ``` ``` Contact neurosurgeon if: Persistent GCS < 8 or = 8 Unexplained confusion > 4h Reduced GCS after admission Progressive neurological signs Incomplete recovery post seizure Penetrating injury Cerebrospinal fluid leak ``` Observations 1/2 hourly GCS until 15

Answer 5

Clot embolus The development of mural or atrial appendage thrombi may occur following a myocardial infarct and co-existing atrial fibrillation may contribute to the formation. They tend to present with classical features of an embolic event.

Answer 6

Direct arterial injury Both vasospasm and arterial injury may complicate supracondylar fractures and are seen in 1% of all cases. Vasospasm is usually transient and more likely when the injury is minor and reduced early. Severely displaced injuries and those with more advanced signs are usually associated with direct arterial injury.

Answer 7

Vasculitis This is likely to represent Buergers disease. It is commonest in young males who smoke heavily.

Answer 8

Combined skeletal and soft tissue reconstruction on a scheduled operating list This patient has a Gustillo-Anderson Grade 3B open fracture. He will require definitive skeletal and soft tissue reconstruction, which should be performed on a combined ortho-plastic scheduled operating list, as per the BOA/BAPRAS guidelines. The surgery does not have to be performed out of scheduled hours unless there is marine/ sewage contamination, vascular compromise or it is a polytrauma. Whilst it is reasonable to apply an external fixator prior to definitive skeletal and soft tissue reconstruction, this should be converted to internal fixation within 72 hours.

Answer 9

Intravenous antibiotics, photography and application of saline soaked gauze with impermeable dressing The initial management of open fractures should include administration of intravenous antibiotics, photography of wound and application of a sterile soaked gauze and impermeable film. The wound should only be handled to remove gross contamination. The patient is then likely to require definitive skeletal and soft tissue reconstruction.

Answer 10

Immediate vascuIar shunting, followed by temporary skeletal stabilisation and vascular reconstruction This patient has a Gustillo-Anderson Grade 3C open fracture with vascular injury. Vascular impairment requires immediate surgery and restoration of circulation, ideally within 3-4 hours. This should follow the sequence of shunting, temporary skeletal stabilisation and then vascular reconstruction as per BOA / BAPRAS guidelines. Revascularisation using vascular shunts should be performed before skeletal fixation.

Answer 11

Computerised tomography of the head Significant facial fractures may have intracranial communication. CT scanning will allow delineation of injury extent and 3D reconstruction images can be created. An Orthopantomogram (OPT) will provide good images of mandible and surrounding bony structures but will not give intracranial detail. A skull x-ray lacks the detail for modern practice. Ocular injuries Superior orbital fissure syndrome Severe force to the lateral wall of the orbit resulting in compression of neurovascular structures. Results in : Complete opthalmoplegia and ptosis (Cranial nerves 3, 4, 6 and nerve to levator palpebrae superioris) Relative afferent pupillary defect Dilatation of the pupil and loss of accommodation and corneal reflexes Altered sensation from forehead to vertex (frontal branch of trigeminal nerve) Orbital blow out fracture Typically occurs when an object of slightly larger diameter than the orbital rim strikes the incompressible eyeball. The bone fragment is displaced downwards into the antral cavity, remaining attached to the orbital periosteum. Periorbital fat may be herniated through the defect, interfering with the inferior rectus and inferior oblique muscles which are contained within the same fascial sheath. This prevents upward movement and outward rotation of the eye and the patient experiences diplopia on upward gaze. The initial bruising and swelling may make assessment difficult and patients should usually be reviewed 5 days later. Residual defects may require orbital floor reconstruction. Nasal Fractures Common injury Ensure new and not old deformity Control epistaxis CSF rhinorrhoea implies that the cribriform plate has been breached and antibiotics will be required. Usually best to allow bruising and swelling to settle and then review patient clinically. Major persistent deformity requires fracture manipulation, best performed within 10 days of injury. Retrobulbar haemorrhage Rare but important ocular emergency. Presents with: Pain (usually sharp and within the globe) Proptosis Pupil reactions are lost Paralysis (eye movements lost) Visual acuity is lost (colour vision is lost first) May be the result of Le Fort type facial fractures. Management: Mannitol 1g/Kg as 20% infusion, Osmotic diuretic, Contra-indicated in congestive heart failure and pulmonary oedema Acetazolamide 500mg IV, (Monitor FBC/U+E) Reduces aqueous pressure by inhibition of carbonic anhydrase (used in glaucoma) Dexamethasone 8mg orally or intravenously In a traumatic setting an urgent cantholysis may be needed prior to definitive surgery. Consider Papaverine 40mg smooth muscle relaxant Dextran 40 500mls IV improves perfusion

Answer 12

Scaphoid fracture Scaphoid fractures usually occur as a result of direct hard blow to the palm or following a fall on the out-stretched hand. The main physical signs are swelling and tenderness in the anatomical snuff box, and pain on wrist movements and on longitudinal compression of the thumb Upper limb fractures Colles' fracture Fall onto extended outstretched hands Described as a dinner fork type deformity Classical Colles' fractures have the following 3 features: Features of the injury 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Occur after a fall on the hand with a rotational force superimposed on it. On examination, there is bruising, swelling and tenderness over the lower end of the forearm. X Rays reveal the displaced fracture of the radius and a prominent ulnar head due to dislocation of the inferior radio-ulnar joint. Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Scaphoid fractures Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal 1/3) The main physical signs are swelling and tenderness in the anatomical snuff box, and pain on wrist movements and on longitudinal compression of the thumb. Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Radial head fracture Fracture of the radial head is common in young adults. It is usually caused by a fall on the outstretched hand. On examination, there is marked local tenderness over the head of the radius, impaired movements at the elbow, and a sharp pain at the lateral side of the elbow at the extremes of rotation (pronation and supination).

Answer 13

Fracture of the radial head Fracture of the radial head is common in young adults. It is usually caused by a fall on the outstretched hand. On examination, there is marked local tenderness over the head of the radius, impaired movements at the elbow, and a sharp pain at the lateral side of the elbow at the extremes of rotation (pronation and supination). Upper limb fractures Colles' fracture Fall onto extended outstretched hands Described as a dinner fork type deformity Classical Colles' fractures have the following 3 features: Features of the injury 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Occur after a fall on the hand with a rotational force superimposed on it. On examination, there is bruising, swelling and tenderness over the lower end of the forearm. X Rays reveal the displaced fracture of the radius and a prominent ulnar head due to dislocation of the inferior radio-ulnar joint. Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Scaphoid fractures Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal 1/3) The main physical signs are swelling and tenderness in the anatomical snuff box, and pain on wrist movements and on longitudinal compression of the thumb. Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Radial head fracture Fracture of the radial head is common in young adults. It is usually caused by a fall on the outstretched hand. On examination, there is marked local tenderness over the head of the radius, impaired movements at the elbow, and a sharp pain at the lateral side of the elbow at the extremes of rotation (pronation and supination).

Answer 14

Galeazzi fracture Galeazzi fractures occur after a fall on the hand with a rotational force superimposed on it. On examination, there is bruising, swelling and tenderness over the lower end of the forearm. X- Rays reveal a displaced fracture of the radius and a prominent ulnar head due to dislocation of the inferior radio-ulnar joint. Upper limb fractures Colles' fracture Fall onto extended outstretched hands Described as a dinner fork type deformity Classical Colles' fractures have the following 3 features: Features of the injury 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Occur after a fall on the hand with a rotational force superimposed on it. On examination, there is bruising, swelling and tenderness over the lower end of the forearm. X Rays reveal the displaced fracture of the radius and a prominent ulnar head due to dislocation of the inferior radio-ulnar joint. Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Scaphoid fractures Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal 1/3) The main physical signs are swelling and tenderness in the anatomical snuff box, and pain on wrist movements and on longitudinal compression of the thumb. Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Radial head fracture Fracture of the radial head is common in young adults. It is usually caused by a fall on the outstretched hand. On examination, there is marked local tenderness over the head of the radius, impaired movements at the elbow, and a sharp pain at the lateral side of the elbow at the extremes of rotation (pronation and supination).

Answer 15

Application of futura splint and fracture clinic review A fracture may still be present and should be immobilised until repeat imaging can be performed. If clinical suspicion persists then subsequent imaging should be with MRI scanning or CT if MRI is contra-indicated. Scaphoid fractures: 80% of all carpal fractures 80% occur in men 80% occur at the waist of the scaphoid Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal third) Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Complications Non union of scaphoid Avascular necrosis of the scaphoid Scapholunate disruption and wrist collapse Degenerative changes of the adjacent joint

Answer 16

Discharge with reassurance This patient is at extremely low risk of having sustained a scaphoid injury and may be discharged. Scaphoid fractures: 80% of all carpal fractures 80% occur in men 80% occur at the waist of the scaphoid Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal third) Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Complications Non union of scaphoid Avascular necrosis of the scaphoid Scapholunate disruption and wrist collapse Degenerative changes of the adjacent joint

Answer 17

Admission and surgical debridement This is technically an open fracture and should be debrided prior to attempted fixation (which should occur soon after). Scaphoid fractures: 80% of all carpal fractures 80% occur in men 80% occur at the waist of the scaphoid Scaphoid fractures are the commonest carpal fractures. Surface of scaphoid is covered by articular cartilage with small area available for blood vessels (fracture risks blood supply) Forms floor of anatomical snuffbox Risk of fracture associated with fall onto outstretched hand (tubercle, waist, or proximal third) Ulnar deviation AP needed for visualization of scaphoid Immobilization of scaphoid fractures difficult Complications Non union of scaphoid Avascular necrosis of the scaphoid Scapholunate disruption and wrist collapse Degenerative changes of the adjacent joint

Answer 18

Transient synovitis Viral illnesses can be associated with transient synovitis. The WCC should ideally be > 12 and the ESR > 40 to suggest septic arthritis.

Answer 19

Perthes disease This child is short, has hyperactivity (disruptive behaviour) and is within the age range for Perthes disease. Hyperactivity and short stature are associated with Perthes disease.

Answer 20

Slipped upper femoral epiphysis Slipped upper femoral epiphysis is commonest in obese adolescent males. The x-ray will show displacement of the femoral epiphysis inferolaterally. Treatment is usually with rest and non weight bearing crutches.

Answer 21

Angioplasty Short segment disease and good run off with tissue loss is a compelling indication for angioplasty. He should receive aspirin and a statin if not already taking them. Peripheral vascular disease ``` Indications for surgery to revascularise the lower limb Intermittent claudication Critical ischaemia Ulceration Gangrene ``` Intermittent claudication that is not disabling may provide a relative indication, whilst the other complaints are often absolute indications depending upon the frailty of the patient. Assessment Clinical examination Ankle brachial pressure index measurement Duplex arterial ultrasound Angiography (standard, CT or MRI): usually performed only if intervention being considered. Angioplasty In order for angioplasty to be undertaken successfully the artery has to be accessible. The lesion relatively short and reasonable distal vessel runoff. Longer lesions may be amenable to sub-intimal angioplasty. Surgery Surgery will be undertaken where attempts at angioplasty have either failed or are unsuitable. Bypass essentially involves bypassing the affected arterial segment by utilising a graft to run from above the disease to below the disease. As with angioplasty good runoff improves the outcome. Some key concepts with bypass surgery Superficial femoral artery occlusion to the above knee popliteal In the ideal scenario, vein (either in situ or reversed LSV) would the used as a conduit. However, prosthetic material has reasonable 5 year patency rates and some would advocate using this in preference to vein so that vein can be used for other procedures in the future. In general terms either technique is usually associated with an excellent outcome (if run off satisfactory). Procedure Artery dissected out, IV heparin 3,000 units given and then the vessels are cross clamped Longitudinal arteriotomy Graft cut to size and tunneled to arteriotomy sites Anastomosis to femoral artery usually with 5/0 'double ended' Prolene suture Distal anastomosis usually using 6/0 'double ended' Prolene Distal disease Femoro-distal bypass surgery takes longer to perform, is more technically challenging and has higher failure rates. In elderly diabetic patients with poor runoff a primary amputation may well be a safer and more effective option. There is no point in embarking on this type of surgery in patients who are wheelchair bound. In femorodistal bypasses vein gives superior outcomes to PTFE. Rules Vein mapping 1st to see whether there is suitable vein (the preferred conduit). Sub intimal hyperplasia occurs early when PTFE is used for the distal anastomosis and will lead to early graft occlusion and failure. Essential operative procedure as for above knee fem-pop. If there is insufficient vein for the entire conduit then vein can be attached to the end of the PTFE graft and then used for the distal anastomosis. This type of 'vein boot' is technically referred to as a Miller Cuff and is associated with better patency rates than PTFE alone. Remember the more distal the arterial anastomosis the lower the success rate.

Answer 22

Conservative management with medical therapy and exercise Structured exercise programmes combined with medical therapy will improve many patients. Should his symptoms worsen or fail to improve then imaging with duplex scanning would be required. Peripheral vascular disease ``` Indications for surgery to revascularise the lower limb Intermittent claudication Critical ischaemia Ulceration Gangrene ``` Intermittent claudication that is not disabling may provide a relative indication, whilst the other complaints are often absolute indications depending upon the frailty of the patient. Assessment Clinical examination Ankle brachial pressure index measurement Duplex arterial ultrasound Angiography (standard, CT or MRI): usually performed only if intervention being considered. Angioplasty In order for angioplasty to be undertaken successfully the artery has to be accessible. The lesion relatively short and reasonable distal vessel runoff. Longer lesions may be amenable to sub-intimal angioplasty. Surgery Surgery will be undertaken where attempts at angioplasty have either failed or are unsuitable. Bypass essentially involves bypassing the affected arterial segment by utilising a graft to run from above the disease to below the disease. As with angioplasty good runoff improves the outcome. Some key concepts with bypass surgery Superficial femoral artery occlusion to the above knee popliteal In the ideal scenario, vein (either in situ or reversed LSV) would the used as a conduit. However, prosthetic material has reasonable 5 year patency rates and some would advocate using this in preference to vein so that vein can be used for other procedures in the future. In general terms either technique is usually associated with an excellent outcome (if run off satisfactory). Procedure Artery dissected out, IV heparin 3,000 units given and then the vessels are cross clamped Longitudinal arteriotomy Graft cut to size and tunneled to arteriotomy sites Anastomosis to femoral artery usually with 5/0 'double ended' Prolene suture Distal anastomosis usually using 6/0 'double ended' Prolene Distal disease Femoro-distal bypass surgery takes longer to perform, is more technically challenging and has higher failure rates. In elderly diabetic patients with poor runoff a primary amputation may well be a safer and more effective option. There is no point in embarking on this type of surgery in patients who are wheelchair bound. In femorodistal bypasses vein gives superior outcomes to PTFE. Rules Vein mapping 1st to see whether there is suitable vein (the preferred conduit). Sub intimal hyperplasia occurs early when PTFE is used for the distal anastomosis and will lead to early graft occlusion and failure. Essential operative procedure as for above knee fem-pop. If there is insufficient vein for the entire conduit then vein can be attached to the end of the PTFE graft and then used for the distal anastomosis. This type of 'vein boot' is technically referred to as a Miller Cuff and is associated with better patency rates than PTFE alone. Remember the more distal the arterial anastomosis the lower the success rate.

Answer 23

Primary amputation Poor runoff and sepsis would equate to poor outcome with attempted bypass surgery. Peripheral vascular disease ``` Indications for surgery to revascularise the lower limb Intermittent claudication Critical ischaemia Ulceration Gangrene ``` Intermittent claudication that is not disabling may provide a relative indication, whilst the other complaints are often absolute indications depending upon the frailty of the patient. Assessment Clinical examination Ankle brachial pressure index measurement Duplex arterial ultrasound Angiography (standard, CT or MRI): usually performed only if intervention being considered. Angioplasty In order for angioplasty to be undertaken successfully the artery has to be accessible. The lesion relatively short and reasonable distal vessel runoff. Longer lesions may be amenable to sub-intimal angioplasty. Surgery Surgery will be undertaken where attempts at angioplasty have either failed or are unsuitable. Bypass essentially involves bypassing the affected arterial segment by utilising a graft to run from above the disease to below the disease. As with angioplasty good runoff improves the outcome. Some key concepts with bypass surgery Superficial femoral artery occlusion to the above knee popliteal In the ideal scenario, vein (either in situ or reversed LSV) would the used as a conduit. However, prosthetic material has reasonable 5 year patency rates and some would advocate using this in preference to vein so that vein can be used for other procedures in the future. In general terms either technique is usually associated with an excellent outcome (if run off satisfactory). Procedure Artery dissected out, IV heparin 3,000 units given and then the vessels are cross clamped Longitudinal arteriotomy Graft cut to size and tunneled to arteriotomy sites Anastomosis to femoral artery usually with 5/0 'double ended' Prolene suture Distal anastomosis usually using 6/0 'double ended' Prolene Distal disease Femoro-distal bypass surgery takes longer to perform, is more technically challenging and has higher failure rates. In elderly diabetic patients with poor runoff a primary amputation may well be a safer and more effective option. There is no point in embarking on this type of surgery in patients who are wheelchair bound. In femorodistal bypasses vein gives superior outcomes to PTFE. Rules Vein mapping 1st to see whether there is suitable vein (the preferred conduit). Sub intimal hyperplasia occurs early when PTFE is used for the distal anastomosis and will lead to early graft occlusion and failure. Essential operative procedure as for above knee fem-pop. If there is insufficient vein for the entire conduit then vein can be attached to the end of the PTFE graft and then used for the distal anastomosis. This type of 'vein boot' is technically referred to as a Miller Cuff and is associated with better patency rates than PTFE alone. Remember the more distal the arterial anastomosis the lower the success rate.

Answer 24

Smith's This is a Smith fracture (reverse Colles' fracture); unlike a Colles' this is a high velocity injury and may require surgical correction. Note that Colles' fractures are usually dorsally displaced. Eponymous fractures Colles' fracture (dinner fork deformity) Fall onto extended outstretched hand Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Direct blow Pott's fracture Bimalleolar ankle fracture Forced foot eversion Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Involvement of the joint is a defining feature

Answer 25

Monteggia's This constellation of injuries is referred to as a Monteggia's fracture. Eponymous fractures Colles' fracture (dinner fork deformity) Fall onto extended outstretched hand Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Direct blow Pott's fracture Bimalleolar ankle fracture Forced foot eversion Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Involvement of the joint is a defining feature

Answer 26

Galeazzi Isolated fracture of the radius alone can occur but is rare. Always check for associated injury. Eponymous fractures Colles' fracture (dinner fork deformity) Fall onto extended outstretched hand Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) Volar angulation of distal radius fragment (Garden spade deformity) Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture Intra-articular fracture of the first carpometacarpal joint Impact on flexed metacarpal, caused by fist fights X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture Dislocation of the proximal radioulnar joint in association with an ulna fracture Fall on outstretched hand with forced pronation Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture Radial shaft fracture with associated dislocation of the distal radioulnar joint Direct blow Pott's fracture Bimalleolar ankle fracture Forced foot eversion Barton's fracture Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation Fall onto extended and pronated wrist Involvement of the joint is a defining feature

Answer 27

Torsades de pointes: Treatment IV magnesium sulphate This woman is likely to have hypokalaemia and hypomagnasaemia as a result of vomiting. In addition to this, the erythromycin will predispose her to torsades de pointes. The patient needs Magnesium 2g over 10 minutes. Knowledge of the management of this peri arrest diagnosis is hence important in surgical practice. Torsades de pointes Torsades de pointes ('twisting of the points') is a rare arrhythmia associated with a long QT interval. It may deteriorate into ventricular fibrillation and hence lead to sudden death ``` Causes of long QT interval congenital: Jervell-Lange-Nielsen syndrome, Romano-Ward syndrome antiarrhythmics: amiodarone, sotalol, class 1a antiarrhythmic drugs tricyclic antidepressants antipsychotics chloroquine terfenadine erythromycin electrolyte: hypocalcaemia, hypokalaemia, hypomagnesaemia myocarditis hypothermia subarachnoid haemorrhage ``` Management IV magnesium sulphate

Answer 28

Immediate exploration and repair The five P's of arterial injury include pain, parasthesias, pallor, pulselessness and paralysis. In the extremities, the tissues most sensitive to anoxia are the peripheral nerves and striated muscle. The early developments of paresthesias and paralysis are signals that there is significant ischemia present, and immediate exploration and repair are warranted. The presence of palpable pulse does not exclude an arterial injury because this presence may represent a transmitted pulsation through a blood clot. When severe ischemia is present, the repair must be completed within 6 to 8 h to prevent irreversible muscle ischemia and loss of limb function. Delay to obtain a conventional angiogram or to observe for change needlessly prolongs the ischemic time. A CT angiogram may be a reasonable alternative. Fasciotomy may be required but should be done in conjunction with and after re-establishment of arterial flow. Local wound exploration is not recommended because brisk hemorrhage may be encountered without the securing of prior vascular control.

Answer 29

This is a typical presentation of pseudogout. An elevated transferrin saturation may indicate haemochromatosis, a recognised cause of pseudogout. A high ferritin level is also seen in haemochromatosis but can be raised in a variety of infective and inflammatory processes, including pseudogout, as part of an acute phase response. Pseudogout Pseudogout is a form of microcrystal synovitis caused by the deposition of calcium pyrophosphate dihydrate in the synovium ``` Risk factors hyperparathyroidism hypothyroidism haemochromatosis acromegaly low magnesium, low phosphate Wilson's disease ``` Features knee, wrist and shoulders most commonly affected joint aspiration: weakly-positively birefringent rhomboid shaped crystals x-ray: chondrocalcinosis Management aspiration of joint fluid, to exclude septic arthritis NSAIDs or intra-articular, intra-muscular or oral steroids as for gout

Answer 30

Operate on next emergency list They would not tolerate removal in the emergency department. The tympanic membrane should be carefully inspected and again this will be easier under general anaesthesia. Management of acute cases- Paediatric Children will often insert objects into orifices such as the nose and external auditory meatus Assessment includes assessment of airway and haemodynamic status Where the airway is not immediately threatened decisions can be made as to whether to manage in the emergency department or transfer to theatre In general children do not tolerate procedures well and it is usually safer to remove objects in theatre and under general anaesthesia with a secure airway A chest x-ray is required to ensure that no object is present in the chest, not all objects are radioopaque. However, signs such as focal consolidation may indicate small airway obstruction In the case of small bore missile injuries the decision relating to surgery depends on the size of the missile and its location. Airgun pellets are a common culprit, if there is a long time interval between the incident and presentation and the object has not caused any significant problems then it may be best left alone Airgun pellets (and glass) lodged in the soft tissues are usually notoriously difficult to localise and extract, no matter how superficial. Removal in theatre is usually the best option. If the object is radioopaque then an image intensifier should be used

Answer 31

Immediate emergency theatre As they are cyanosed it requires immediate removal and this should be undertaken in a fully staffed theatre. Ideally a rigid bronchoscopy should be performed. Management of acute cases- Paediatric Children will often insert objects into orifices such as the nose and external auditory meatus Assessment includes assessment of airway and haemodynamic status Where the airway is not immediately threatened decisions can be made as to whether to manage in the emergency department or transfer to theatre In general children do not tolerate procedures well and it is usually safer to remove objects in theatre and under general anaesthesia with a secure airway A chest x-ray is required to ensure that no object is present in the chest, not all objects are radioopaque. However, signs such as focal consolidation may indicate small airway obstruction In the case of small bore missile injuries the decision relating to surgery depends on the size of the missile and its location. Airgun pellets are a common culprit, if there is a long time interval between the incident and presentation and the object has not caused any significant problems then it may be best left alone Airgun pellets (and glass) lodged in the soft tissues are usually notoriously difficult to localise and extract, no matter how superficial. Removal in theatre is usually the best option. If the object is radioopaque then an image intensifier should be used

Answer 32

Manage conservatively The pellet is small and no serious injury has occurred at this stage. This should therefore be managed conservatively. Management of acute cases- Paediatric Children will often insert objects into orifices such as the nose and external auditory meatus Assessment includes assessment of airway and haemodynamic status Where the airway is not immediately threatened decisions can be made as to whether to manage in the emergency department or transfer to theatre In general children do not tolerate procedures well and it is usually safer to remove objects in theatre and under general anaesthesia with a secure airway A chest x-ray is required to ensure that no object is present in the chest, not all objects are radioopaque. However, signs such as focal consolidation may indicate small airway obstruction In the case of small bore missile injuries the decision relating to surgery depends on the size of the missile and its location. Airgun pellets are a common culprit, if there is a long time interval between the incident and presentation and the object has not caused any significant problems then it may be best left alone Airgun pellets (and glass) lodged in the soft tissues are usually notoriously difficult to localise and extract, no matter how superficial. Removal in theatre is usually the best option. If the object is radioopaque then an image intensifier should be used

Answer 33

USS in 6 months At this point continue with ultrasound surveillance Abdominal aorta aneurysm Abdominal aortic aneurysms are a common problem in vascular surgery. They may occur as either true or false aneurysm. With the former all 3 layers of the arterial wall are involved, in the latter only a single layer of fibrous tissue forms the aneurysm wall. True abdominal aortic aneurysms have an approximate incidence of 0.06 per 1000 people. They are commonest in elderly men and for this reason the UK is now introducing the aneurysm screening program with the aim of performing an abdominal aortic ultrasound measurement in all men aged 65 years. Causes Several different groups of patients suffer from aneurysmal disease. The commonest group is those who suffer from standard arterial disease, i.e. Those who are hypertensive and have been or are smokers. Other patients such as those suffering from connective tissue diseases such as Marfan's may also develop aneurysms. In patients with abdominal aortic aneurysms the extracellular matrix becomes disrupted with a change in the balance of collagen and elastic fibres. Management Most abdominal aortic aneurysms are an incidental finding. Symptoms most often relate to rupture or impending rupture. 20% rupture anteriorly into the peritoneal cavity. Very poor prognosis. 80% rupture posteriorly into the retroperitoneal space The risk of rupture is related to aneurysm size, only 2% of aneurysms measuring less than 4cm in diameter will rupture over a 5 year period. This contrasts with 75% of aneurysms measuring over 7cm in diameter. This is well explained by Laplaces' law which relates size to transmural pressure. For this reason most vascular surgeons will subject patients with an aneurysm size of 5cm or greater to CT scanning of the chest, abdomen and pelvis with the aim of delineating anatomy and planning treatment. Depending upon co-morbidities, surgery is generally offered once the aneurysm is between 5.5cm and 6cm. A CT reconstruction showing an infrarenal abdominal aortic aneurysm. The walls of the sac are calcified which may facilitate identification on plain x-rays Image sourced from Wikipedia Indications for surgery Symptomatic aneurysms (80% annual mortality if untreated) Increasing size above 5.5cm if asymptomatic Rupture (100% mortality without surgery) Surgical procedures Abdominal aortic aneurysm repair Procedure: GA Invasive monitoring (A-line, CVP, catheter) Incision: Midline or transverse Bowel and distal duodenum mobilised to access aorta. Aneurysm neck and base dissected out and prepared for cross clamp Systemic heparinisation Cross clamp (proximal first) Longitudinal aortotomy Atherectomy Deal with back bleeding from lumbar vessels and inferior mesenteric artery Insert graft either tube or bifurcated depending upon anatomy Suture using Prolene (3/0 for proximal , distal anastomosis suture varies according to site) Clamps off: End tidal CO2 will rise owing to effects of reperfusion, at this point major risk of myocardial events. Haemostasis Closure of aneurysm sac to minimise risk of aorto-enteric fistula Closure: Loop 1 PDS or Prolene to abdominal wall Skin- surgeons preference Post operatively: ITU (Almost all) Greatest risk of complications following emergency repair Complications: Embolic- gut and foot infarcts Cardiac - owing to premorbid states, re-perfusion injury and effects of cross clamp Wound problems Later risks related to graft- infection and aorto-enteric fistula Special groups Supra renal AAA These patients will require a supra renal clamp and this carries a far higher risk of complications and risk of renal failure. Ruptured AAA Pre-operatively the management depends upon haemodynamic instability. In patients with symptoms of rupture (typical pain, haemodynamic compromise and risk factors) then ideally prompt laparotomy. In those with vague symptoms and haemodynamic stability the ideal test is CT scan to determine whether rupture has occurred or not. Most common rupture site is retroperitoneal 80%. These patients will tend to develop retroperitoneal haematoma. This can be disrupted if Bp is allowed to rise too high so aim for Bp 100mmHg. Operative details are similar to elective repair although surgery should be swift, blind rushing often makes the situation worse. Plunging vascular clamps blindly into a pool of blood at the aneurysm neck carries the risk of injury the vena cava that these patients do not withstand. Occasionally a supracoeliac clamp is needed to effect temporary control, although leaving this applied for more than 20 minutes tends to carry a dismal outcome. ``` EVAR Increasingly patients are now being offered endovascular aortic aneurysm repair. This is undertaken by surgeons and radiologists working jointly. The morphology of the aneurysm is important and not all are suitable. Here is a typical list of those features favoring a suitable aneurysm: Long neck Straight iliac vessels Healthy groin vessels ``` Clearly few AAA patients possess the above and compromise has to be made. The use of fenestrated grafts can allow supra renal AAA to be treated. Procedure: ``` GA Radiology or theatre Bilateral groin incisions Common femoral artery dissected out Heparinisation Arteriotomy and insertion of guide wire Dilation of arteriotomy Insertion of EVAR Device Once in satisfactory position it is released Arteriotomy closed once check angiogram shows good position and no endoleak ``` Complications: Endoleaks depending upon site are either Type I or 2. These may necessitate re-intervention and all EVAR patients require follow up . Details are not needed for MRCS.

Answer 34

AAA repair during next 48 hours Assuming he is fit enough. This would be a typical 'open ' case as the marked iliac disease would make EVAR difficult Abdominal aorta aneurysm Abdominal aortic aneurysms are a common problem in vascular surgery. They may occur as either true or false aneurysm. With the former all 3 layers of the arterial wall are involved, in the latter only a single layer of fibrous tissue forms the aneurysm wall. True abdominal aortic aneurysms have an approximate incidence of 0.06 per 1000 people. They are commonest in elderly men and for this reason the UK is now introducing the aneurysm screening program with the aim of performing an abdominal aortic ultrasound measurement in all men aged 65 years. Causes Several different groups of patients suffer from aneurysmal disease. The commonest group is those who suffer from standard arterial disease, i.e. Those who are hypertensive and have been or are smokers. Other patients such as those suffering from connective tissue diseases such as Marfan's may also develop aneurysms. In patients with abdominal aortic aneurysms the extracellular matrix becomes disrupted with a change in the balance of collagen and elastic fibres. Management Most abdominal aortic aneurysms are an incidental finding. Symptoms most often relate to rupture or impending rupture. 20% rupture anteriorly into the peritoneal cavity. Very poor prognosis. 80% rupture posteriorly into the retroperitoneal space The risk of rupture is related to aneurysm size, only 2% of aneurysms measuring less than 4cm in diameter will rupture over a 5 year period. This contrasts with 75% of aneurysms measuring over 7cm in diameter. This is well explained by Laplaces' law which relates size to transmural pressure. For this reason most vascular surgeons will subject patients with an aneurysm size of 5cm or greater to CT scanning of the chest, abdomen and pelvis with the aim of delineating anatomy and planning treatment. Depending upon co-morbidities, surgery is generally offered once the aneurysm is between 5.5cm and 6cm. A CT reconstruction showing an infrarenal abdominal aortic aneurysm. The walls of the sac are calcified which may facilitate identification on plain x-rays Image sourced from Wikipedia Indications for surgery Symptomatic aneurysms (80% annual mortality if untreated) Increasing size above 5.5cm if asymptomatic Rupture (100% mortality without surgery) Surgical procedures Abdominal aortic aneurysm repair Procedure: GA Invasive monitoring (A-line, CVP, catheter) Incision: Midline or transverse Bowel and distal duodenum mobilised to access aorta. Aneurysm neck and base dissected out and prepared for cross clamp Systemic heparinisation Cross clamp (proximal first) Longitudinal aortotomy Atherectomy Deal with back bleeding from lumbar vessels and inferior mesenteric artery Insert graft either tube or bifurcated depending upon anatomy Suture using Prolene (3/0 for proximal , distal anastomosis suture varies according to site) Clamps off: End tidal CO2 will rise owing to effects of reperfusion, at this point major risk of myocardial events. Haemostasis Closure of aneurysm sac to minimise risk of aorto-enteric fistula Closure: Loop 1 PDS or Prolene to abdominal wall Skin- surgeons preference Post operatively: ITU (Almost all) Greatest risk of complications following emergency repair Complications: Embolic- gut and foot infarcts Cardiac - owing to premorbid states, re-perfusion injury and effects of cross clamp Wound problems Later risks related to graft- infection and aorto-enteric fistula Special groups Supra renal AAA These patients will require a supra renal clamp and this carries a far higher risk of complications and risk of renal failure. Ruptured AAA Pre-operatively the management depends upon haemodynamic instability. In patients with symptoms of rupture (typical pain, haemodynamic compromise and risk factors) then ideally prompt laparotomy. In those with vague symptoms and haemodynamic stability the ideal test is CT scan to determine whether rupture has occurred or not. Most common rupture site is retroperitoneal 80%. These patients will tend to develop retroperitoneal haematoma. This can be disrupted if Bp is allowed to rise too high so aim for Bp 100mmHg. Operative details are similar to elective repair although surgery should be swift, blind rushing often makes the situation worse. Plunging vascular clamps blindly into a pool of blood at the aneurysm neck carries the risk of injury the vena cava that these patients do not withstand. Occasionally a supracoeliac clamp is needed to effect temporary control, although leaving this applied for more than 20 minutes tends to carry a dismal outcome. ``` EVAR Increasingly patients are now being offered endovascular aortic aneurysm repair. This is undertaken by surgeons and radiologists working jointly. The morphology of the aneurysm is important and not all are suitable. Here is a typical list of those features favoring a suitable aneurysm: Long neck Straight iliac vessels Healthy groin vessels ``` Clearly few AAA patients possess the above and compromise has to be made. The use of fenestrated grafts can allow supra renal AAA to be treated. Procedure: ``` GA Radiology or theatre Bilateral groin incisions Common femoral artery dissected out Heparinisation Arteriotomy and insertion of guide wire Dilation of arteriotomy Insertion of EVAR Device Once in satisfactory position it is released Arteriotomy closed once check angiogram shows good position and no endoleak ``` Complications: Endoleaks depending upon site are either Type I or 2. These may necessitate re-intervention and all EVAR patients require follow up . Details are not needed for MRCS.

Answer 35

Palliate He will not survive aortic surgery and whilst some may disagree, I would argue that taking this case to theatre would be futile Abdominal aorta aneurysm Abdominal aortic aneurysms are a common problem in vascular surgery. They may occur as either true or false aneurysm. With the former all 3 layers of the arterial wall are involved, in the latter only a single layer of fibrous tissue forms the aneurysm wall. True abdominal aortic aneurysms have an approximate incidence of 0.06 per 1000 people. They are commonest in elderly men and for this reason the UK is now introducing the aneurysm screening program with the aim of performing an abdominal aortic ultrasound measurement in all men aged 65 years. Causes Several different groups of patients suffer from aneurysmal disease. The commonest group is those who suffer from standard arterial disease, i.e. Those who are hypertensive and have been or are smokers. Other patients such as those suffering from connective tissue diseases such as Marfan's may also develop aneurysms. In patients with abdominal aortic aneurysms the extracellular matrix becomes disrupted with a change in the balance of collagen and elastic fibres. Management Most abdominal aortic aneurysms are an incidental finding. Symptoms most often relate to rupture or impending rupture. 20% rupture anteriorly into the peritoneal cavity. Very poor prognosis. 80% rupture posteriorly into the retroperitoneal space The risk of rupture is related to aneurysm size, only 2% of aneurysms measuring less than 4cm in diameter will rupture over a 5 year period. This contrasts with 75% of aneurysms measuring over 7cm in diameter. This is well explained by Laplaces' law which relates size to transmural pressure. For this reason most vascular surgeons will subject patients with an aneurysm size of 5cm or greater to CT scanning of the chest, abdomen and pelvis with the aim of delineating anatomy and planning treatment. Depending upon co-morbidities, surgery is generally offered once the aneurysm is between 5.5cm and 6cm. A CT reconstruction showing an infrarenal abdominal aortic aneurysm. The walls of the sac are calcified which may facilitate identification on plain x-rays Image sourced from Wikipedia Indications for surgery Symptomatic aneurysms (80% annual mortality if untreated) Increasing size above 5.5cm if asymptomatic Rupture (100% mortality without surgery) Surgical procedures Abdominal aortic aneurysm repair Procedure: GA Invasive monitoring (A-line, CVP, catheter) Incision: Midline or transverse Bowel and distal duodenum mobilised to access aorta. Aneurysm neck and base dissected out and prepared for cross clamp Systemic heparinisation Cross clamp (proximal first) Longitudinal aortotomy Atherectomy Deal with back bleeding from lumbar vessels and inferior mesenteric artery Insert graft either tube or bifurcated depending upon anatomy Suture using Prolene (3/0 for proximal , distal anastomosis suture varies according to site) Clamps off: End tidal CO2 will rise owing to effects of reperfusion, at this point major risk of myocardial events. Haemostasis Closure of aneurysm sac to minimise risk of aorto-enteric fistula Closure: Loop 1 PDS or Prolene to abdominal wall Skin- surgeons preference Post operatively: ITU (Almost all) Greatest risk of complications following emergency repair Complications: Embolic- gut and foot infarcts Cardiac - owing to premorbid states, re-perfusion injury and effects of cross clamp Wound problems Later risks related to graft- infection and aorto-enteric fistula Special groups Supra renal AAA These patients will require a supra renal clamp and this carries a far higher risk of complications and risk of renal failure. Ruptured AAA Pre-operatively the management depends upon haemodynamic instability. In patients with symptoms of rupture (typical pain, haemodynamic compromise and risk factors) then ideally prompt laparotomy. In those with vague symptoms and haemodynamic stability the ideal test is CT scan to determine whether rupture has occurred or not. Most common rupture site is retroperitoneal 80%. These patients will tend to develop retroperitoneal haematoma. This can be disrupted if Bp is allowed to rise too high so aim for Bp 100mmHg. Operative details are similar to elective repair although surgery should be swift, blind rushing often makes the situation worse. Plunging vascular clamps blindly into a pool of blood at the aneurysm neck carries the risk of injury the vena cava that these patients do not withstand. Occasionally a supracoeliac clamp is needed to effect temporary control, although leaving this applied for more than 20 minutes tends to carry a dismal outcome. ``` EVAR Increasingly patients are now being offered endovascular aortic aneurysm repair. This is undertaken by surgeons and radiologists working jointly. The morphology of the aneurysm is important and not all are suitable. Here is a typical list of those features favoring a suitable aneurysm: Long neck Straight iliac vessels Healthy groin vessels ``` Clearly few AAA patients possess the above and compromise has to be made. The use of fenestrated grafts can allow supra renal AAA to be treated. Procedure: ``` GA Radiology or theatre Bilateral groin incisions Common femoral artery dissected out Heparinisation Arteriotomy and insertion of guide wire Dilation of arteriotomy Insertion of EVAR Device Once in satisfactory position it is released Arteriotomy closed once check angiogram shows good position and no endoleak ``` Complications: Endoleaks depending upon site are either Type I or 2. These may necessitate re-intervention and all EVAR patients require follow up . Details are not needed for MRCS.

Answer 36

Stress fractures Repetitive activity and loading of normal bone may result in small hairline fractures. Whilst these may be painful they are seldom displaced. Surrounding soft tissue injury is unusual. They may present late following the injury, in which case callus formation may be identified on radiographs. Such cases may not require formal immobilisation, injuries associated with severe pain and presenting at an earlier stage may benefit from immobilisation tailored to the site of injury. A short history of pain together with clinical examination and radiological signs affecting the second metatarsal favour a stress fracture. The fact that callus is present suggests that immobilisation is unlikely to be beneficial. Freibergs disease is an anterior metatarsalgia affecting the head of the second metarsal, it typically occurs in the pubertal growth spurt. The initial injury was thought to be due to stress microfractures at the growth plate. The key feature in the history which distinguishes the injury as being stress fracture is the radiology. In Freibergs disease the x-ray changes include; joint space widening, formation of bony spurs, sclerosis and flattening of the metatarsal head.

Answer 37

von Willebrand's disease Bleeding post operatively, epistaxis and menorrhagia may indicate a diagnosis of vWD. Haemoarthroses are rare. The bleeding time is usually normal in haemophilia (X-linked) and vitamin K deficiency.

Answer 38

Acquired haemophilia This patient has Factor 8 acquired disorder. He is likely to have developed a lung malignancy (smoker) and as a result aquired a haemophilia disorder. The elderly, pregnancy, malignancy and autoimmune conditions are associated with acquired haemophilia. Prolonged APTT is key to the diagnosis. Management involves steroids.

Answer 39

Antiphospholipid syndrome A combination of thromboembolism and bleeding in a young woman should raise the possibility of antiphospholipid syndrome. Other features may include foetal loss, venous and arterial thrombosis and thrombocytopenia. A Lupus anticoagulant may be present and the APTT is prolonged.

Answer 40

Sural nerve Saphenous vein Long saphenous vein This vein may be harvested for bypass surgery, or removed as treatment for varicose veins with saphenofemoral junction incompetence. Originates at the 1st digit where the dorsal vein merges with the dorsal venous arch of the foot Passes anterior to the medial malleolus and runs up the medial side of the leg At the knee, it runs over the posterior border of the medial epicondyle of the femur bone Then passes laterally to lie on the anterior surface of the thigh before entering an opening in the fascia lata called the saphenous opening It joins with the femoral vein in the region of the femoral triangle at the saphenofemoral junction ``` Tributaries Medial marginal Superficial epigastric Superficial iliac circumflex Superficial external pudendal veins ``` Short saphenous vein Originates at the 5th digit where the dorsal vein merges with the dorsal venous arch of the foot, which attaches to the great saphenous vein. It passes around the lateral aspect of the foot (inferior and posterior to the lateral malleolus) and runs along the posterior aspect of the leg (with the sural nerve) Passes between the heads of the gastrocnemius muscle, and drains into the popliteal vein, approximately at or above the level of the knee joint.

Answer 41

A bisphosphonate, calcium and vitamin D supplementation should be given to all patients aged over 75 years after having a fracture. A DEXA scan is only needed of the patient is aged below 75 years. Hormone replacement therapy has been shown to reduce vertebral and non vertebral fractures, however the risks of cardiovascular disease and breast malignancy make this a less favourable option. Osteoporosis: secondary prevention NICE guidelines were updated in 2008 on the secondary prevention of osteoporotic fractures in postmenopausal women. Key points include Treatment is indicated following osteoporotic fragility fractures in postmenopausal women who are confirmed to have osteoporosis (a T-score of - 2.5 SD or below). In women aged 75 years or older, a DEXA scan may not be required 'if the responsible clinician considers it to be clinically inappropriate or unfeasible' Vitamin D and calcium supplementation should be offered to all women unless the clinician is confident they have adequate calcium intake and are vitamin D replete Alendronate is first-line Around 25% of patients cannot tolerate alendronate, usually due to upper gastrointestinal problems. These patients should be offered risedronate or etidronate (see treatment criteria below) Strontium ranelate and raloxifene are recommended if patients cannot tolerate bisphosphonates (see treatment criteria below) Supplementary notes on treatment Bisphosphonates Alendronate, risedronate and etidronate are all licensed for the prevention and treatment of post-menopausal and glucocorticoid-induced osteoporosis All three have been shown to reduce the risk of both vertebral and non-vertebral fractures although alendronate, risedronate may be superior to etidronate in preventing hip fractures Ibandronate is a once-monthly oral bisphosphonate Vitamin D and calcium Poor evidence base to suggest reduced fracture rates in the general population at risk of osteoporotic fractures - may reduce rates in frail, housebound patients Raloxifene - selective oestrogen receptor modulator (SERM) Has been shown to prevent bone loss and to reduce the risk of vertebral fractures, but has not yet been shown to reduce the risk of non-vertebral fractures Has been shown to increase bone density in the spine and proximal femur May worsen menopausal symptoms Increased risk of thromboembolic events May decrease risk of breast cancer Strontium ranelate 'Dual action bone agent' - increases deposition of new bone by osteoblasts and reduces the resorption of bone by osteoclasts Strong evidence base, may be second-line treatment in near future Increased risk of thromboembolic events

Answer 42

The earliest detectable radiological evidence is a radiolucency of the affected area coupled with subchondral collapse. Radiolucency and subchondral collapse are late changes. The earliest evidence on plain films is the affected area appearing as being more radio-opaque due to hyperaemia and resorption of the neighboring area. It may be diagnosed earlier using bone scans and MRI. Avascular necrosis Cellular death of bone components due to interruption of the blood supply, causing bone destruction Main joints affected are hip, scaphoid, lunate and the talus. It is not the same as non union. The fracture has usually united. Radiological evidence is slow to appear. Vascular ingrowth into the affected bone may occur. However, many joints will develop secondary osteoarthritis. ``` Causes P ancreatitis L upus A lcohol S teroids T rauma I diopathic, infection C aisson disease, collagen vascular disease R adiation, rheumatoid arthritis A myloid G aucher disease S ickle cell disease ``` Presentation Usually pain. Often despite apparent fracture union. Investigation MRI scanning will show changes earlier than plain films. Treatment In fractures at high risk sites anticipation is key. Early prompt and accurate reduction is essential. Non weight bearing may help to facilitate vascular regeneration. Joint replacement may be necessary, or even the preferred option (e.g. Hip in the elderly).

Answer 43

Admit for open reduction and fixation Unlike an osteoporotic fracture in an elderly lady this is a high velocity injury and will require surgical fixation. Fracture management Bony injury resulting in a fracture may arise from trauma (excessive forces applied to bone), stress related (repetitive low velocity injury) or pathological (abnormal bone which fractures during normal use of following minimal trauma) Diagnosis involves not just evaluating the fracture ; such as site and type of injury but also other associated injuries and distal neurovascular deficits. This may entail not just clinical examination but radiographs of proximal and distal joints. When assessing x-rays it is important to assess for changes in length of the bone, the angulation of the distal bone, rotational effects, presence of material such as glass. Key points in management of fractures Immobilise the fracture including the proximal and distal joints Carefully monitor and document neurovascular status, particularly following reduction and immobilisation Manage infection including tetanus prophylaxis IV broad spectrum antibiotics for open injuries As a general principle all open fractures should be thoroughly debrided ( and internal fixation devices avoided or used with extreme caution) Open fractures constitute an emergency and should be debrided and lavaged within 6 hours of injury

Answer 44

Fasciotomy The delay is the significant factor here. These injuries often have neurovascular compromise and inactivity now places him at risk of developing complications. In compartment syndrome the loss of arterial pulsation occurs late. Fracture management Bony injury resulting in a fracture may arise from trauma (excessive forces applied to bone), stress related (repetitive low velocity injury) or pathological (abnormal bone which fractures during normal use of following minimal trauma) Diagnosis involves not just evaluating the fracture ; such as site and type of injury but also other associated injuries and distal neurovascular deficits. This may entail not just clinical examination but radiographs of proximal and distal joints. When assessing x-rays it is important to assess for changes in length of the bone, the angulation of the distal bone, rotational effects, presence of material such as glass. Key points in management of fractures Immobilise the fracture including the proximal and distal joints Carefully monitor and document neurovascular status, particularly following reduction and immobilisation Manage infection including tetanus prophylaxis IV broad spectrum antibiotics for open injuries As a general principle all open fractures should be thoroughly debrided ( and internal fixation devices avoided or used with extreme caution) Open fractures constitute an emergency and should be debrided and lavaged within 6 hours of injury

Answer 45

Discharge home with futura splint and fracture clinic appointment This could well be a scaphoid fracture and should be temporarily immobilised pending further review. A futura splint will immobilise better than an arm sling for this problem. Fracture management Bony injury resulting in a fracture may arise from trauma (excessive forces applied to bone), stress related (repetitive low velocity injury) or pathological (abnormal bone which fractures during normal use of following minimal trauma) Diagnosis involves not just evaluating the fracture ; such as site and type of injury but also other associated injuries and distal neurovascular deficits. This may entail not just clinical examination but radiographs of proximal and distal joints. When assessing x-rays it is important to assess for changes in length of the bone, the angulation of the distal bone, rotational effects, presence of material such as glass. Key points in management of fractures Immobilise the fracture including the proximal and distal joints Carefully monitor and document neurovascular status, particularly following reduction and immobilisation Manage infection including tetanus prophylaxis IV broad spectrum antibiotics for open injuries As a general principle all open fractures should be thoroughly debrided ( and internal fixation devices avoided or used with extreme caution) Open fractures constitute an emergency and should be debrided and lavaged within 6 hours of injury

Answer 46

Debridement and rotational flap Nasal injuries can be challenging to manage and where there is tissue loss, it can be difficult to primarily close them and still obtain a satisfactory aesthetic result. Debridement together with a rotational flap would obtain the best results here. Primary closure Clean wound, usually surgically created or following minor trauma Standard suturing methods will usually suffice Wound heals by primary intention Delayed primary closure Similar methods of actual closure to primary closure May be used in situations where primary closure is either not achievable or not advisable e.g. infection Vacuum assisted closure Uses negative pressure therapy to facilitate wound closure Sponge is inserted into wound cavity and then negative pressure applied Advantages include removal of exudate and versatility Disadvantages include cost and risk of fistulation if used incorrectly on sites such as bowel Split thickness skin grafts Superficial dermis removed with Watson knife or dermatome (commonly from thigh) Remaining epithelium regenerates from dermal appendages Coverage may be increased by meshing Full thickness skin grafts Whole dermal thickness is removed Sub dermal fat is then removed and graft placed over donor site Better cosmesis and flexibility at recipient site Donor site "cost" Flaps Viable tissue with a blood supply May be pedicled or free Pedicled flaps are more reliable, but limited in range Free flaps have greater range but carry greater risk of breakdown as they require vascular anastomosis

Answer 47

Wound excision and primary closure By debriding the wound, the area can then be primarily closed. Prophylactic antibiotics should be administered. Primary closure Clean wound, usually surgically created or following minor trauma Standard suturing methods will usually suffice Wound heals by primary intention Delayed primary closure Similar methods of actual closure to primary closure May be used in situations where primary closure is either not achievable or not advisable e.g. infection Vacuum assisted closure Uses negative pressure therapy to facilitate wound closure Sponge is inserted into wound cavity and then negative pressure applied Advantages include removal of exudate and versatility Disadvantages include cost and risk of fistulation if used incorrectly on sites such as bowel Split thickness skin grafts Superficial dermis removed with Watson knife or dermatome (commonly from thigh) Remaining epithelium regenerates from dermal appendages Coverage may be increased by meshing Full thickness skin grafts Whole dermal thickness is removed Sub dermal fat is then removed and graft placed over donor site Better cosmesis and flexibility at recipient site Donor site "cost" Flaps Viable tissue with a blood supply May be pedicled or free Pedicled flaps are more reliable, but limited in range Free flaps have greater range but carry greater risk of breakdown as they require vascular anastomosis

Answer 48

Debridement and healing by secondary intention The skin changes described here should be debrided. Closure would not be safe with the skin changes documented and the wound should be left open. Primary closure Clean wound, usually surgically created or following minor trauma Standard suturing methods will usually suffice Wound heals by primary intention Delayed primary closure Similar methods of actual closure to primary closure May be used in situations where primary closure is either not achievable or not advisable e.g. infection Vacuum assisted closure Uses negative pressure therapy to facilitate wound closure Sponge is inserted into wound cavity and then negative pressure applied Advantages include removal of exudate and versatility Disadvantages include cost and risk of fistulation if used incorrectly on sites such as bowel Split thickness skin grafts Superficial dermis removed with Watson knife or dermatome (commonly from thigh) Remaining epithelium regenerates from dermal appendages Coverage may be increased by meshing Full thickness skin grafts Whole dermal thickness is removed Sub dermal fat is then removed and graft placed over donor site Better cosmesis and flexibility at recipient site Donor site "cost" Flaps Viable tissue with a blood supply May be pedicled or free Pedicled flaps are more reliable, but limited in range Free flaps have greater range but carry greater risk of breakdown as they require vascular anastomosis

Answer 49

Rupture of the aorta distal to the left subclavian artery The aorta may be injured in deceleration accidents. In the setting of deceleration injury, chest pain and mediastinal widening the most likely problem is aortic rupture. This will typically occur distal to the left subclavian artery. Rupture of the proximal aorta may occur. However, survival is unlikely. It is important to note that the question uses the term Most likely injury as this is the component that distinguishes an ascending rupture from a descending rupture. Thoracic aorta rupture Mechanism of injury: Decelerating force i.e. RTA, fall from a great height Most people die at scene Survivors may have an incomplete laceration at the ligamentum arteriosum of the aorta. Clinical features Contained haematoma: persistent hypotension Detected mainly by history, CXR changes CXR changes Widened mediastinum Trachea/Oesophagus to right Depression of left main stem bronchus Widened paratracheal stripe/paraspinal interfaces Space between aorta and pulmonary artery obliterated Rib fracture/left haemothorax Diagnosis Angiography, usually CT aortogram.

Answer 50

Urgent neurosurgical review (even before CT head performed) A patient with GCS <8 or = to 8 needs urgent neurosurgical review. Especially when an open fracture is present. Head injury management- NICE Guidelines Summary of guidelines All patients should be assessed within 15 minutes on arrival to A&E Document all 3 components of the GCS If GCS <8 or = to 8, consider stabilising the airway Treat pain with low dose IV opiates (if safe) Full spine immobilisation until assessment if: - GCS < 15 - neck pain/tenderness - paraesthesia extremities - focal neurological deficit - suspected c-spine injury If a c-spine injury is suspected a 3 view c-spine x-ray is indicated. CT c-spine is preferred if: - Intubated - GCS <13 - Normal x-ray but continued concerns regarding c-spine injury - Any focal neurology - A CT head scan is being performed - Initial plain films are abnormal ``` Immediate CT head (within 1 hour) if: GCS < 13 on admission GCS < 15 2 hours after admission Suspected open or depressed skull fracture Suspected skull base fracture (panda eyes, Battle's sign, CSF from nose/ear, bleeding ear) Focal neurology Vomiting > 1 episode Post traumatic seizure Coagulopathy ``` ``` Contact neurosurgeon if: Persistent GCS < 8 or = 8 Unexplained confusion > 4h Reduced GCS after admission Progressive neurological signs Incomplete recovery post seizure Penetrating injury Cerebrospinal fluid leak ``` Observations 1/2 hourly GCS until 15

Answer 51

CT head within 1 hour This patient has a basal skull fracture, which is indicated by a positive Battle's sign. He should have a CT head within 1h. Head injury management- NICE Guidelines Summary of guidelines All patients should be assessed within 15 minutes on arrival to A&E Document all 3 components of the GCS If GCS <8 or = to 8, consider stabilising the airway Treat pain with low dose IV opiates (if safe) Full spine immobilisation until assessment if: - GCS < 15 - neck pain/tenderness - paraesthesia extremities - focal neurological deficit - suspected c-spine injury If a c-spine injury is suspected a 3 view c-spine x-ray is indicated. CT c-spine is preferred if: - Intubated - GCS <13 - Normal x-ray but continued concerns regarding c-spine injury - Any focal neurology - A CT head scan is being performed - Initial plain films are abnormal ``` Immediate CT head (within 1 hour) if: GCS < 13 on admission GCS < 15 2 hours after admission Suspected open or depressed skull fracture Suspected skull base fracture (panda eyes, Battle's sign, CSF from nose/ear, bleeding ear) Focal neurology Vomiting > 1 episode Post traumatic seizure Coagulopathy ``` ``` Contact neurosurgeon if: Persistent GCS < 8 or = 8 Unexplained confusion > 4h Reduced GCS after admission Progressive neurological signs Incomplete recovery post seizure Penetrating injury Cerebrospinal fluid leak ``` Observations 1/2 hourly GCS until 15

Answer 52

3 view c-spine xray In the January 2014 NICE guidance relating to the diagnosis of head and spinal injury the evidence for initial imaging of the C spine was reviewed. The current UK practice is that "low risk" patients with pain but no neurology undergo a 3 view C spine x-ray. The more detailed 5 view x-ray was not found to be any better than 3 view films. In patients with high risk injuries (which the patient in the scenario does not have) there is a likelihood that 1 in 6 injuries would be missed on plain films alone and therefore CT scanning of the C spine is recommended in this group. Head injury management- NICE Guidelines Summary of guidelines All patients should be assessed within 15 minutes on arrival to A&E Document all 3 components of the GCS If GCS <8 or = to 8, consider stabilising the airway Treat pain with low dose IV opiates (if safe) Full spine immobilisation until assessment if: - GCS < 15 - neck pain/tenderness - paraesthesia extremities - focal neurological deficit - suspected c-spine injury If a c-spine injury is suspected a 3 view c-spine x-ray is indicated. CT c-spine is preferred if: - Intubated - GCS <13 - Normal x-ray but continued concerns regarding c-spine injury - Any focal neurology - A CT head scan is being performed - Initial plain films are abnormal ``` Immediate CT head (within 1 hour) if: GCS < 13 on admission GCS < 15 2 hours after admission Suspected open or depressed skull fracture Suspected skull base fracture (panda eyes, Battle's sign, CSF from nose/ear, bleeding ear) Focal neurology Vomiting > 1 episode Post traumatic seizure Coagulopathy ``` ``` Contact neurosurgeon if: Persistent GCS < 8 or = 8 Unexplained confusion > 4h Reduced GCS after admission Progressive neurological signs Incomplete recovery post seizure Penetrating injury Cerebrospinal fluid leak ``` Observations 1/2 hourly GCS until 15

Answer 53

Catheter directed tPA Axillary vein thrombosis 1-2% of all deep venous thrombosis Primary cause is associated with trauma, thoracic outlet obstruction or repeated effort in a dominant arm (young active individuals) Secondary causes include central line insertion, malignancy, pacemakers ``` Clinical features Pain and swelling (non pitting) Numbness Discolouration: mottling, dusky Pulses present Congested veins ``` ``` Investigations FBC: viscosity, platelet function Clotting Liver function tests D-dimer Duplex scan: investigation of choice CT scan: thoracic outlet obstruction ``` Treatment Local catheter directed TPA Heparin Warfarin

Answer 54

Transfusion associated lung injury The pulmonary catheter reading indicates that this is not a case of fluid overload (the PCWP should be high, normal values PCWP systolic 7mmHg, diastolic 10mmHg). Transfusion associated lung injury is a rare reaction causing neutrophilic mediated allergic pulmonary oedema. Patient's have antibodies to donor leukocytes. It is important to consider this as a diagnosis when patients don't respond to treatment for pulmonary oedema. Patients normally respond to supportive therapy including fluids and oxygen. Blood transfusion reactions Acute transfusion reactions present as adverse signs or symptoms during or within 24 hours of a blood transfusion. The most frequent reactions are fever, chills, pruritus, or urticaria, which typically resolve promptly without specific treatment or complications. Other signs occurring in temporal relationship with a blood transfusion, such as severe dyspnoea, pyrexia, or loss of consciousness may be the first indication of a more severe potentially fatal reaction. The causes of adverse reactions are multi-factorial. Immune mediated reactions, some of the most feared, occur as a result of component mismatch, the commonest cause of which is clerical error. More common, non immune mediated, complications may occur as a result of product contamination, this may be bacterial or viral. Transfusion related lung injury is well recognised and there are two proposed mechanisms which underpin this. One involves the sequestration of primed neutrophils within the recipient pulmonary capillary bed. The other proposed mechanism suggests that HLA mismatches between donor neutrophils and recipient lung tissue is to blame.

Answer 55

Graft vs. Host disease This is associated with transfusion of unirradiated blood in immunosupressed patients. Transfusion associated GVHD can occur 4-30 days after a transfusion and follows a sub acute pathway. Patients may also have diarrhoea and abnormal liver function tests. Management involves steroid therapy. Blood transfusion reactions Acute transfusion reactions present as adverse signs or symptoms during or within 24 hours of a blood transfusion. The most frequent reactions are fever, chills, pruritus, or urticaria, which typically resolve promptly without specific treatment or complications. Other signs occurring in temporal relationship with a blood transfusion, such as severe dyspnoea, pyrexia, or loss of consciousness may be the first indication of a more severe potentially fatal reaction. The causes of adverse reactions are multi-factorial. Immune mediated reactions, some of the most feared, occur as a result of component mismatch, the commonest cause of which is clerical error. More common, non immune mediated, complications may occur as a result of product contamination, this may be bacterial or viral. Transfusion related lung injury is well recognised and there are two proposed mechanisms which underpin this. One involves the sequestration of primed neutrophils within the recipient pulmonary capillary bed. The other proposed mechanism suggests that HLA mismatches between donor neutrophils and recipient lung tissue is to blame.

Answer 56

Acute haemolytic transfusion reaction Rapid intravascular haemolysis leading to shock, DIC and death can occur with this reaction. Blood transfusion reactions Acute transfusion reactions present as adverse signs or symptoms during or within 24 hours of a blood transfusion. The most frequent reactions are fever, chills, pruritus, or urticaria, which typically resolve promptly without specific treatment or complications. Other signs occurring in temporal relationship with a blood transfusion, such as severe dyspnoea, pyrexia, or loss of consciousness may be the first indication of a more severe potentially fatal reaction. The causes of adverse reactions are multi-factorial. Immune mediated reactions, some of the most feared, occur as a result of component mismatch, the commonest cause of which is clerical error. More common, non immune mediated, complications may occur as a result of product contamination, this may be bacterial or viral. Transfusion related lung injury is well recognised and there are two proposed mechanisms which underpin this. One involves the sequestration of primed neutrophils within the recipient pulmonary capillary bed. The other proposed mechanism suggests that HLA mismatches between donor neutrophils and recipient lung tissue is to blame.

Answer 57

Nystagmus Orbital apex syndrome This is an extension of superior orbital fissure syndrome and includes compression of the optic nerve passing through the optic foramen. It is indicated by features of superior orbital fissure syndrome and ipsilateral afferent pupillary defect. This type of injury will result in the orbital apex syndrome (See above). As such opthalmoplegia will be present and nystagmus cannot occur. Le Fort 1 The fracture extends from the nasal septum to the lateral pyriform rims, travels horizontally above the teeth apices, crosses below the zygomaticomaxillary junction, and traverses the pterygomaxillary junction to interrupt the pterygoid plates. Le Fort 2 These fractures have a pyramidal shape and extend from the nasal bridge at or below the nasofrontal suture through the frontal process of the maxilla, inferolaterally through the lacrimal bones and inferior orbital floor and rim through or near the inferior orbital foramen, and inferiorly through the anterior wall of the maxillary sinus; it then travels under the zygoma, across the pterygomaxillary fissure, and through the pterygoid plates. Le Fort 3 These fractures start at the nasofrontal and frontomaxillary sutures and extend posteriorly along the medial wall of the orbit through the nasolacrimal groove and ethmoid bones. The thicker sphenoid bone posteriorly usually prevents continuation of the fracture into the optic canal. Instead, the fracture continues along the floor of the orbit along the inferior orbital fissure and continues superolaterally through the lateral orbital wall, through the zygomaticofrontal junction and the zygomatic arch. Intranasally, a branch of the fracture extends through the base of the perpendicular plate of the ethmoid, through the vomer, and through the interface of the pterygoid plates to the base of the sphenoid. This type of fracture predisposes the patient to CSF rhinorrhea more commonly than the other types. Ocular injuries Superior orbital fissure syndrome Severe force to the lateral wall of the orbit resulting in compression of neurovascular structures. Results in : Complete opthalmoplegia and ptosis (Cranial nerves 3, 4, 6 and nerve to levator palpebrae superioris) Relative afferent pupillary defect Dilatation of the pupil and loss of accommodation and corneal reflexes Altered sensation from forehead to vertex (frontal branch of trigeminal nerve) Orbital blow out fracture Typically occurs when an object of slightly larger diameter than the orbital rim strikes the incompressible eyeball. The bone fragment is displaced downwards into the antral cavity, remaining attached to the orbital periosteum. Periorbital fat may be herniated through the defect, interfering with the inferior rectus and inferior oblique muscles which are contained within the same fascial sheath. This prevents upward movement and outward rotation of the eye and the patient experiences diplopia on upward gaze. The initial bruising and swelling may make assessment difficult and patients should usually be reviewed 5 days later. Residual defects may require orbital floor reconstruction. Nasal Fractures Common injury Ensure new and not old deformity Control epistaxis CSF rhinorrhoea implies that the cribriform plate has been breached and antibiotics will be required. Usually best to allow bruising and swelling to settle and then review patient clinically. Major persistent deformity requires fracture manipulation, best performed within 10 days of injury. Retrobulbar haemorrhage Rare but important ocular emergency. Presents with: Pain (usually sharp and within the globe) Proptosis Pupil reactions are lost Paralysis (eye movements lost) Visual acuity is lost (colour vision is lost first) May be the result of Le Fort type facial fractures. Management: Mannitol 1g/Kg as 20% infusion, Osmotic diuretic, Contra-indicated in congestive heart failure and pulmonary oedema Acetazolamide 500mg IV, (Monitor FBC/U+E) Reduces aqueous pressure by inhibition of carbonic anhydrase (used in glaucoma) Dexamethasone 8mg orally or intravenously In a traumatic setting an urgent cantholysis may be needed prior to definitive surgery. Consider Papaverine 40mg smooth muscle relaxant Dextran 40 500mls IV improves perfusion

Answer 58

Curlings Ulcer Stress ulcers may occur in the duodenum of burns patients and are more common in children. ``` Depth of burn assessment Bleeding on needle prick Sensation Appearance Blanching to pressure ``` Percentage burn estimation Lund Browder chart: most accurate even in children Wallace rule of nines Palmar surface: surface area palm = 0.8% burn >15% body surface area burns in adults needs urgent burn fluid resuscitation ``` Transfer to burn centre if: Need burn shock resuscitation Face/hands/genitals affected Deep partial thickness or full thickness burns Significant electrical/chemical burns ``` Management The initial aim is to stop the burning process and resuscitate the patient. Intravenous fluids will be required for children with burns greater than 10% of total body surface area. Adults with burns greater than 15% of total body surface area will also require IV fluids. The fluids are calculated using the Parkland formula which is; volume of fluid= total body surface area of the burn % x weight (Kg) x4. Half of the fluid is administered in the first 8 hours. A urinary catheter should be inserted. Analgesia should be given. Complex burns, burns involving the hand perineum and face and burns >10% in adults and >5% in children should be transferred to a burns unit. Circumferential burns affecting a limb or severe torso burns impeding respiration may require escharotomy to divide the burnt tissue. Conservative management is appropriate for superficial burns and mixed superficial burns that will heal in 2 weeks. More complex burns may require excision and skin grafting. Excision and primary closure is not generally practised as there is a high risk of infection. There is no evidence to support the use of anti microbial prophylaxis or topical antibiotics in burn patients. Escharotomies Indicated in circumferential full thickness burns to the torso or limbs. Careful division of the encasing band of burn tissue will potentially improve ventilation (if the burn involves the torso), or relieve compartment syndrome and oedema (where a limb is involved)

Answer 59

Rhabdomyolysis Electrical high voltage burns are associated with rhabdomyolysis. Acute tubular necrosis may occur. Aggressive IV fluids should be given ``` Depth of burn assessment Bleeding on needle prick Sensation Appearance Blanching to pressure ``` Percentage burn estimation Lund Browder chart: most accurate even in children Wallace rule of nines Palmar surface: surface area palm = 0.8% burn >15% body surface area burns in adults needs urgent burn fluid resuscitation ``` Transfer to burn centre if: Need burn shock resuscitation Face/hands/genitals affected Deep partial thickness or full thickness burns Significant electrical/chemical burns ``` Management The initial aim is to stop the burning process and resuscitate the patient. Intravenous fluids will be required for children with burns greater than 10% of total body surface area. Adults with burns greater than 15% of total body surface area will also require IV fluids. The fluids are calculated using the Parkland formula which is; volume of fluid= total body surface area of the burn % x weight (Kg) x4. Half of the fluid is administered in the first 8 hours. A urinary catheter should be inserted. Analgesia should be given. Complex burns, burns involving the hand perineum and face and burns >10% in adults and >5% in children should be transferred to a burns unit. Circumferential burns affecting a limb or severe torso burns impeding respiration may require escharotomy to divide the burnt tissue. Conservative management is appropriate for superficial burns and mixed superficial burns that will heal in 2 weeks. More complex burns may require excision and skin grafting. Excision and primary closure is not generally practised as there is a high risk of infection. There is no evidence to support the use of anti microbial prophylaxis or topical antibiotics in burn patients. Escharotomies Indicated in circumferential full thickness burns to the torso or limbs. Careful division of the encasing band of burn tissue will potentially improve ventilation (if the burn involves the torso), or relieve compartment syndrome and oedema (where a limb is involved)

Answer 60

Compartment syndrome Circumferential burns may constrict the limb and cause a compartment syndrome to develop. Eshcarotomy is required, and compartmental decompression. ``` Depth of burn assessment Bleeding on needle prick Sensation Appearance Blanching to pressure ``` Percentage burn estimation Lund Browder chart: most accurate even in children Wallace rule of nines Palmar surface: surface area palm = 0.8% burn >15% body surface area burns in adults needs urgent burn fluid resuscitation ``` Transfer to burn centre if: Need burn shock resuscitation Face/hands/genitals affected Deep partial thickness or full thickness burns Significant electrical/chemical burns ``` Management The initial aim is to stop the burning process and resuscitate the patient. Intravenous fluids will be required for children with burns greater than 10% of total body surface area. Adults with burns greater than 15% of total body surface area will also require IV fluids. The fluids are calculated using the Parkland formula which is; volume of fluid= total body surface area of the burn % x weight (Kg) x4. Half of the fluid is administered in the first 8 hours. A urinary catheter should be inserted. Analgesia should be given. Complex burns, burns involving the hand perineum and face and burns >10% in adults and >5% in children should be transferred to a burns unit. Circumferential burns affecting a limb or severe torso burns impeding respiration may require escharotomy to divide the burnt tissue. Conservative management is appropriate for superficial burns and mixed superficial burns that will heal in 2 weeks. More complex burns may require excision and skin grafting. Excision and primary closure is not generally practised as there is a high risk of infection. There is no evidence to support the use of anti microbial prophylaxis or topical antibiotics in burn patients. Escharotomies Indicated in circumferential full thickness burns to the torso or limbs. Careful division of the encasing band of burn tissue will potentially improve ventilation (if the burn involves the torso), or relieve compartment syndrome and oedema (where a limb is involved)

Answer 61

Multilayer compression bandaging Unfortunately lymphoedema may complicate redo varicose vein surgery (in 0.5% of cases). As the presentation is mild, she should be managed using compression hosiery. Diuretics do not help in cases of true lymphoedema and a dramatic response suggests an alternative underlying cause. Lymphoedema Due to impaired lymphatic drainage in the presence of normal capillary function. Lymphoedema causes the accumulation of protein rich fluid, subdermal fibrosis and dermal thickening. Characteristically fluid is confined to the epifascial space (skin and subcutaneous tissues); muscle compartments are free of oedema. It involves the foot, unlike other forms of oedema. There may be a 'buffalo hump' on the dorsum of the foot and the skin cannot be pinched due to subcutaneous fibrosis. Causes of lymphoedema Primary Congenital < 1 year: sporadic, Milroy's disease Onset 1-35 years: sporadic, Meige's disease > 35 years: Tarda Secondary Bacterial/fungal/parasitic infection (filariasis) Lymphatic malignancy Radiotherapy to lymph nodes Surgical resection of lymph nodes DVT Thrombophlebitis Indications for surgery Marked disability or deformity from limb swelling Lymphoedema caused by proximal lymphatic obstruction with patent distal lymphatics suitable for a lymphatic drainage procedure Lymphocutaneous fistulae and megalymphatics Procedures Homans operation Reduction procedure with preservation of overlying skin (which must be in good condition). Skin flaps are raised and the underlying tissue excised. Limb circumference typically reduced by a third. Charles operation All skin and subcutaneous tissue around the calf are excised down to the deep fascia. Split skin grafts are placed over the site. May be performed if overlying skin is not in good condition. Larger reduction in size than with Homans procedure. Lymphovenous anastamosis Identifiable lymphatics are anastomosed to sub dermal venules. Usually indicated in 2% of patients with proximal lymphatic obstruction and normal distal lymphatics.

Answer 62

Homans operation Surgery is indicated in less than 10% of cases. However, severe deformity is one of the indications for surgery. Lymphovenous anastomosis is indicated where the proximal lymphatics are not patent. When the overlying skin is healthy (and limb deformity a problem), a Homans procedure is a reasonable first line operative option. Lymphoedema Due to impaired lymphatic drainage in the presence of normal capillary function. Lymphoedema causes the accumulation of protein rich fluid, subdermal fibrosis and dermal thickening. Characteristically fluid is confined to the epifascial space (skin and subcutaneous tissues); muscle compartments are free of oedema. It involves the foot, unlike other forms of oedema. There may be a 'buffalo hump' on the dorsum of the foot and the skin cannot be pinched due to subcutaneous fibrosis. Causes of lymphoedema Primary Congenital < 1 year: sporadic, Milroy's disease Onset 1-35 years: sporadic, Meige's disease > 35 years: Tarda Secondary Bacterial/fungal/parasitic infection (filariasis) Lymphatic malignancy Radiotherapy to lymph nodes Surgical resection of lymph nodes DVT Thrombophlebitis Indications for surgery Marked disability or deformity from limb swelling Lymphoedema caused by proximal lymphatic obstruction with patent distal lymphatics suitable for a lymphatic drainage procedure Lymphocutaneous fistulae and megalymphatics Procedures Homans operation Reduction procedure with preservation of overlying skin (which must be in good condition). Skin flaps are raised and the underlying tissue excised. Limb circumference typically reduced by a third. Charles operation All skin and subcutaneous tissue around the calf are excised down to the deep fascia. Split skin grafts are placed over the site. May be performed if overlying skin is not in good condition. Larger reduction in size than with Homans procedure. Lymphovenous anastamosis Identifiable lymphatics are anastomosed to sub dermal venules. Usually indicated in 2% of patients with proximal lymphatic obstruction and normal distal lymphatics.

Answer 63

Lymphovenous anastomosis In young patients with proximal disease and healthy distal lymphatics a lymphovenous anastomosis may be considered. Such cases are rare. Lymphoedema Due to impaired lymphatic drainage in the presence of normal capillary function. Lymphoedema causes the accumulation of protein rich fluid, subdermal fibrosis and dermal thickening. Characteristically fluid is confined to the epifascial space (skin and subcutaneous tissues); muscle compartments are free of oedema. It involves the foot, unlike other forms of oedema. There may be a 'buffalo hump' on the dorsum of the foot and the skin cannot be pinched due to subcutaneous fibrosis. Causes of lymphoedema Primary Congenital < 1 year: sporadic, Milroy's disease Onset 1-35 years: sporadic, Meige's disease > 35 years: Tarda Secondary Bacterial/fungal/parasitic infection (filariasis) Lymphatic malignancy Radiotherapy to lymph nodes Surgical resection of lymph nodes DVT Thrombophlebitis Indications for surgery Marked disability or deformity from limb swelling Lymphoedema caused by proximal lymphatic obstruction with patent distal lymphatics suitable for a lymphatic drainage procedure Lymphocutaneous fistulae and megalymphatics Procedures Homans operation Reduction procedure with preservation of overlying skin (which must be in good condition). Skin flaps are raised and the underlying tissue excised. Limb circumference typically reduced by a third. Charles operation All skin and subcutaneous tissue around the calf are excised down to the deep fascia. Split skin grafts are placed over the site. May be performed if overlying skin is not in good condition. Larger reduction in size than with Homans procedure. Lymphovenous anastamosis Identifiable lymphatics are anastomosed to sub dermal venules. Usually indicated in 2% of patients with proximal lymphatic obstruction and normal distal lymphatics.

Answer 64

Hydrocortisone 100mg IV This patient has acute adrenal insufficiency and urgently needs steroid replacement. Addisonian crisis Causes Sepsis or surgery causing an acute exacerbation of chronic insufficiency (Addison's, Hypopituitarism) Adrenal haemorrhage eg Waterhouse-Friderichsen syndrome (fulminant meningococcemia) Steroid withdrawal Management Hydrocortisone 100 mg im or iv 1 litre normal saline infused over 30-60 mins or with dextrose if hypoglycaemic Continue hydrocortisone 6 hourly until the patient is stable. No fludrocortisone is required because high cortisol exerts weak mineralocorticoid action Oral replacement may begin after 24 hours and be reduced to maintenance over 3-4 days

Answer 65

Intercostal tube drain insertion He requires a chest drain and analgesia. In general all haemopneumothoraces should be managed by intercostal chest drain insertion as they have a risk of becoming a tension pneumothorax until the lung laceration has sealed. Thoracic trauma Types of thoracic trauma Tension pneumothorax Often laceration to lung parenchyma with flap Pressure develops in thorax Most common cause is mechanical ventilation in patient with pleural injury Symptoms overlap with cardiac tamponade, hyper-resonant percussion note is more likely in tension pnemothorax Flail chest Chest wall disconnects from thoracic cage Multiple rib fractures (at least two fractures per rib in at least two ribs) Associated with pulmonary contusion Abnormal chest motion Avoid over hydration and fluid overload Pneumothorax Most common cause is lung laceration with air leakage Most traumatic pneumothoraces should have a chest drain Patients with traumatic pneumothorax should never be mechanically ventilated until a chest drain is inserted Haemothorax Most commonly due to laceration of lung, intercostal vessel or internal mammary artery Haemothoraces large enough to appear on CXR are treated with large bore chest drain Surgical exploration is warranted if >1500ml blood drained immediately Cardiac tamponade Beck's triad: elevated venous pressure, reduced arterial pressure, reduced heart sounds Pulsus paradoxus May occur with as little as 100ml blood Pulmonary contusion Most common potentially lethal chest injury Arterial blood gases and pulse oximetry important Early intubation within an hour if significant hypoxia Blunt cardiac injury Usually occurs secondary to chest wall injury ECG may show features of myocardial infarction Sequelae: hypotension, arrhythmias, cardiac wall motion abnormalities Aorta disruption Deceleration injuries Contained haematoma Widened mediastinum Diaphragm disruption Most due to motor vehicle accidents and blunt trauma causing large radial tears (laceration injuries result in small tears) More common on left side Insert gastric tube, may pass into intrathoracic stomach Mediastinal traversing wounds Entrance wound in one hemithorax and exit wound/foreign body in opposite hemithorax Mediastinal haematoma or pleural cap suggests great vessel injury Mortality is 20%

Answer 66

Thoracotomy This is one indication for an 'emergency room' thoracotomy, there are not many others! Typical injuries include ventricular penetration, great vessel disruption and hilar lung injuries. Thoracic trauma Types of thoracic trauma Tension pneumothorax Often laceration to lung parenchyma with flap Pressure develops in thorax Most common cause is mechanical ventilation in patient with pleural injury Symptoms overlap with cardiac tamponade, hyper-resonant percussion note is more likely in tension pnemothorax Flail chest Chest wall disconnects from thoracic cage Multiple rib fractures (at least two fractures per rib in at least two ribs) Associated with pulmonary contusion Abnormal chest motion Avoid over hydration and fluid overload Pneumothorax Most common cause is lung laceration with air leakage Most traumatic pneumothoraces should have a chest drain Patients with traumatic pneumothorax should never be mechanically ventilated until a chest drain is inserted Haemothorax Most commonly due to laceration of lung, intercostal vessel or internal mammary artery Haemothoraces large enough to appear on CXR are treated with large bore chest drain Surgical exploration is warranted if >1500ml blood drained immediately Cardiac tamponade Beck's triad: elevated venous pressure, reduced arterial pressure, reduced heart sounds Pulsus paradoxus May occur with as little as 100ml blood Pulmonary contusion Most common potentially lethal chest injury Arterial blood gases and pulse oximetry important Early intubation within an hour if significant hypoxia Blunt cardiac injury Usually occurs secondary to chest wall injury ECG may show features of myocardial infarction Sequelae: hypotension, arrhythmias, cardiac wall motion abnormalities Aorta disruption Deceleration injuries Contained haematoma Widened mediastinum Diaphragm disruption Most due to motor vehicle accidents and blunt trauma causing large radial tears (laceration injuries result in small tears) More common on left side Insert gastric tube, may pass into intrathoracic stomach Mediastinal traversing wounds Entrance wound in one hemithorax and exit wound/foreign body in opposite hemithorax Mediastinal haematoma or pleural cap suggests great vessel injury Mortality is 20%

Answer 67

Intercostal tube drain insertion Unlike spontaneous pneumothoraces most would advocate chest tube drainage in the context of pneumothorax resulting from trauma. This is because of the risk of the lung laceration developing a tension. Once there is no further evidence of air leak the chest drain may be removed and a check x-ray performed to check there is no re-accumulation prior to discharge. Thoracic trauma Types of thoracic trauma Tension pneumothorax Often laceration to lung parenchyma with flap Pressure develops in thorax Most common cause is mechanical ventilation in patient with pleural injury Symptoms overlap with cardiac tamponade, hyper-resonant percussion note is more likely in tension pnemothorax Flail chest Chest wall disconnects from thoracic cage Multiple rib fractures (at least two fractures per rib in at least two ribs) Associated with pulmonary contusion Abnormal chest motion Avoid over hydration and fluid overload Pneumothorax Most common cause is lung laceration with air leakage Most traumatic pneumothoraces should have a chest drain Patients with traumatic pneumothorax should never be mechanically ventilated until a chest drain is inserted Haemothorax Most commonly due to laceration of lung, intercostal vessel or internal mammary artery Haemothoraces large enough to appear on CXR are treated with large bore chest drain Surgical exploration is warranted if >1500ml blood drained immediately Cardiac tamponade Beck's triad: elevated venous pressure, reduced arterial pressure, reduced heart sounds Pulsus paradoxus May occur with as little as 100ml blood Pulmonary contusion Most common potentially lethal chest injury Arterial blood gases and pulse oximetry important Early intubation within an hour if significant hypoxia Blunt cardiac injury Usually occurs secondary to chest wall injury ECG may show features of myocardial infarction Sequelae: hypotension, arrhythmias, cardiac wall motion abnormalities Aorta disruption Deceleration injuries Contained haematoma Widened mediastinum Diaphragm disruption Most due to motor vehicle accidents and blunt trauma causing large radial tears (laceration injuries result in small tears) More common on left side Insert gastric tube, may pass into intrathoracic stomach Mediastinal traversing wounds Entrance wound in one hemithorax and exit wound/foreign body in opposite hemithorax Mediastinal haematoma or pleural cap suggests great vessel injury Mortality is 20%

Answer 68

Torn meniscus Twisting sporting injuries followed by delayed onset of knee swelling and locking are strongly suggestive of a menisceal tear. Arthroscopic menisectomy is the usual treatment. Knee injury Types of injury Ruptured anterior cruciate ligament Sport injury Mechanism: high twisting force applied to a bent knee Typically presents with: loud crack, pain and RAPID joint swelling (haemoarthrosis) Poor healing Management: intense physiotherapy or surgery Ruptured posterior cruciate ligament Mechanism: hyperextension injuries Tibia lies back on the femur Paradoxical anterior draw test Rupture of medial collateral ligament Mechanism: leg forced into valgus via force outside the leg Knee unstable when put into valgus position Menisceal tear Rotational sporting injuries Delayed knee swelling Joint locking (Patient may develop skills to "unlock" the knee Recurrent episodes of pain and effusions are common, often following minor trauma Chondromalacia patellae Teenage girls, following an injury to knee e.g. Dislocation patella Typical history of pain on going downstairs or at rest Tenderness, quadriceps wasting Dislocation of the patella Most commonly occurs as a traumatic primary event, either through direct trauma or through severe contraction of quadriceps with knee stretched in valgus and external rotation Genu valgum, tibial torsion and high riding patella are risk factors Skyline x-ray views of patella are required, although displaced patella may be clinically obvious An osteochondral fracture is present in 5% The condition has a 20% recurrence rate Fractured patella 2 types: i. Direct blow to patella causing undisplaced fragments ii. Avulsion fracture Tibial plateau fracture Occur in the elderly (or following significant trauma in young) Mechanism: knee forced into valgus or varus, but the knee fractures before the ligaments rupture Varus injury affects medial plateau and if valgus injury, lateral plateau depressed fracture occurs Classified using the Schatzker system (see below)

Answer 69

Posterior cruciate ligament rupture In ruptured posterior cruciate ligament the tibia lies back on the femur and can be drawn forward during a paradoxical draw test. Knee injury Types of injury Ruptured anterior cruciate ligament Sport injury Mechanism: high twisting force applied to a bent knee Typically presents with: loud crack, pain and RAPID joint swelling (haemoarthrosis) Poor healing Management: intense physiotherapy or surgery Ruptured posterior cruciate ligament Mechanism: hyperextension injuries Tibia lies back on the femur Paradoxical anterior draw test Rupture of medial collateral ligament Mechanism: leg forced into valgus via force outside the leg Knee unstable when put into valgus position Menisceal tear Rotational sporting injuries Delayed knee swelling Joint locking (Patient may develop skills to "unlock" the knee Recurrent episodes of pain and effusions are common, often following minor trauma Chondromalacia patellae Teenage girls, following an injury to knee e.g. Dislocation patella Typical history of pain on going downstairs or at rest Tenderness, quadriceps wasting Dislocation of the patella Most commonly occurs as a traumatic primary event, either through direct trauma or through severe contraction of quadriceps with knee stretched in valgus and external rotation Genu valgum, tibial torsion and high riding patella are risk factors Skyline x-ray views of patella are required, although displaced patella may be clinically obvious An osteochondral fracture is present in 5% The condition has a 20% recurrence rate Fractured patella 2 types: i. Direct blow to patella causing undisplaced fragments ii. Avulsion fracture Tibial plateau fracture Occur in the elderly (or following significant trauma in young) Mechanism: knee forced into valgus or varus, but the knee fractures before the ligaments rupture Varus injury affects medial plateau and if valgus injury, lateral plateau depressed fracture occurs Classified using the Schatzker system (see below)

Answer 70

Anterior cruciate ligament rupture This is common in footballers as the football boot studs stick to the ground and high twisting force is applied to a flexed knee. Rapid joint swelling also supports the diagnosis. Knee injury Types of injury Ruptured anterior cruciate ligament Sport injury Mechanism: high twisting force applied to a bent knee Typically presents with: loud crack, pain and RAPID joint swelling (haemoarthrosis) Poor healing Management: intense physiotherapy or surgery Ruptured posterior cruciate ligament Mechanism: hyperextension injuries Tibia lies back on the femur Paradoxical anterior draw test Rupture of medial collateral ligament Mechanism: leg forced into valgus via force outside the leg Knee unstable when put into valgus position Menisceal tear Rotational sporting injuries Delayed knee swelling Joint locking (Patient may develop skills to "unlock" the knee Recurrent episodes of pain and effusions are common, often following minor trauma Chondromalacia patellae Teenage girls, following an injury to knee e.g. Dislocation patella Typical history of pain on going downstairs or at rest Tenderness, quadriceps wasting Dislocation of the patella Most commonly occurs as a traumatic primary event, either through direct trauma or through severe contraction of quadriceps with knee stretched in valgus and external rotation Genu valgum, tibial torsion and high riding patella are risk factors Skyline x-ray views of patella are required, although displaced patella may be clinically obvious An osteochondral fracture is present in 5% The condition has a 20% recurrence rate Fractured patella 2 types: i. Direct blow to patella causing undisplaced fragments ii. Avulsion fracture Tibial plateau fracture Occur in the elderly (or following significant trauma in young) Mechanism: knee forced into valgus or varus, but the knee fractures before the ligaments rupture Varus injury affects medial plateau and if valgus injury, lateral plateau depressed fracture occurs Classified using the Schatzker system (see below)

Answer 71

Superficial venous insufficiency Venous ulcers are usually associated with features of venous insufficiency. These include haemosiderin deposition and varicose veins. Neuropathic ulcers will tend to present at sites of pressure, which is not typically at the medial malleolus. Venous leg ulcers Most due to venous hypertension, secondary to chronic venous insufficiency (other causes include calf pump dysfunction or neuromuscular disorders) Ulcers form due to capillary fibrin cuff or leucocyte sequestration Features of venous insufficiency include oedema, brown pigmentation, lipodermatosclerosis, eczema Location above the ankle, painless Deep venous insufficiency is related to previous DVT and superficial venous insufficiency is associated with varicose veins Doppler ultrasound looks for presence of reflux and duplex ultrasound looks at the anatomy/ flow of the vein Management: 4 layer compression banding after exclusion of arterial disease or surgery If fail to heal after 12 weeks or >10cm2 skin grafting may be needed Marjolin's ulcer Image sourced from Wikipedia Squamous cell carcinoma Occurring at sites of chronic inflammation e.g; burns, osteomyelitis after 10-20 years Mainly occur on the lower limb ``` Arterial ulcers Occur on the toes and heel Painful There may be areas of gangrene Cold with no palpable pulses Low ABPI measurements ``` Neuropathic ulcers Commonly over plantar surface of metatarsal head and plantar surface of hallux The plantar neuropathic ulcer is the condition that most commonly leads to amputation in diabetic patients Due to pressure Management includes cushioned shoes to reduce callus formation Pyoderma gangrenosum Image sourced from Wikipedia Associated with inflammatory bowel disease/RA Can occur at stoma sites Erythematous nodules or pustules which ulcerate

Answer 72

Chronic obliterative arterial disease Painful ulcers associated with a low ABPI are usually arterial in nature. The question does not indicate that features of chronic venous insufficiency are present. Patients may have mild pitting oedema as many vascular patients will also have ischaemic heart disease and elevated right heart pressures. The absence of more compelling signs of venous insufficiency makes a mixed ulcer less likely. Venous leg ulcers Most due to venous hypertension, secondary to chronic venous insufficiency (other causes include calf pump dysfunction or neuromuscular disorders) Ulcers form due to capillary fibrin cuff or leucocyte sequestration Features of venous insufficiency include oedema, brown pigmentation, lipodermatosclerosis, eczema Location above the ankle, painless Deep venous insufficiency is related to previous DVT and superficial venous insufficiency is associated with varicose veins Doppler ultrasound looks for presence of reflux and duplex ultrasound looks at the anatomy/ flow of the vein Management: 4 layer compression banding after exclusion of arterial disease or surgery If fail to heal after 12 weeks or >10cm2 skin grafting may be needed Marjolin's ulcer Image sourced from Wikipedia Squamous cell carcinoma Occurring at sites of chronic inflammation e.g; burns, osteomyelitis after 10-20 years Mainly occur on the lower limb ``` Arterial ulcers Occur on the toes and heel Painful There may be areas of gangrene Cold with no palpable pulses Low ABPI measurements ``` Neuropathic ulcers Commonly over plantar surface of metatarsal head and plantar surface of hallux The plantar neuropathic ulcer is the condition that most commonly leads to amputation in diabetic patients Due to pressure Management includes cushioned shoes to reduce callus formation Pyoderma gangrenosum Image sourced from Wikipedia Associated with inflammatory bowel disease/RA Can occur at stoma sites Erythematous nodules or pustules which ulcerate

Answer 73

Squamous cell carcinoma If after many years an ulcer becomes heaped up and irregular, with rolled edges then suspect a squamous cell carcinoma. Venous leg ulcers Most due to venous hypertension, secondary to chronic venous insufficiency (other causes include calf pump dysfunction or neuromuscular disorders) Ulcers form due to capillary fibrin cuff or leucocyte sequestration Features of venous insufficiency include oedema, brown pigmentation, lipodermatosclerosis, eczema Location above the ankle, painless Deep venous insufficiency is related to previous DVT and superficial venous insufficiency is associated with varicose veins Doppler ultrasound looks for presence of reflux and duplex ultrasound looks at the anatomy/ flow of the vein Management: 4 layer compression banding after exclusion of arterial disease or surgery If fail to heal after 12 weeks or >10cm2 skin grafting may be needed Marjolin's ulcer Image sourced from Wikipedia Squamous cell carcinoma Occurring at sites of chronic inflammation e.g; burns, osteomyelitis after 10-20 years Mainly occur on the lower limb ``` Arterial ulcers Occur on the toes and heel Painful There may be areas of gangrene Cold with no palpable pulses Low ABPI measurements ``` Neuropathic ulcers Commonly over plantar surface of metatarsal head and plantar surface of hallux The plantar neuropathic ulcer is the condition that most commonly leads to amputation in diabetic patients Due to pressure Management includes cushioned shoes to reduce callus formation Pyoderma gangrenosum Image sourced from Wikipedia Associated with inflammatory bowel disease/RA Can occur at stoma sites Erythematous nodules or pustules which ulcerate

Answer 74

Hypoglossal nerve The jugular foramen may be divided into three compartments: Anterior compartment transmits the inferior petrosal sinus Middle compartment transmits cranial nerves IX, X and XI Posterior compartment transmits the sigmoid sinus ``` Foramen ovale Sphenoid bone Otic ganglion V3 (Mandibular nerve:3rd branch of trigeminal) Accessory meningeal artery Lesser petrosal nerve Emissary veins ``` Foramen spinosum Sphenoid bone Middle meningeal artery Meningeal branch of the Mandibular nerve Foramen rotundum Sphenoid bone Maxillary nerve (V2) Foramen lacerum/ carotid canal Sphenoid bone Base of the medial pterygoid plate. Internal carotid artery* Nerve and artery of the pterygoid canal Jugular foramen Temporal bone Anterior: inferior petrosal sinus Intermediate: glossopharyngeal, vagus, and accessory nerves. Posterior: sigmoid sinus (becoming the internal jugular vein) and some meningeal branches from the occipital and ascending pharyngeal arteries. Foramen magnum Occipital bone Anterior and posterior spinal arteries Vertebral arteries Medulla oblongata Stylomastoid foramen Temporal bone Stylomastoid artery Facial nerve Superior orbital fissure Sphenoid bone Oculomotor nerve (III) Recurrent meningeal artery Trochlear nerve (IV) Lacrimal, frontal and nasociliary branches of ophthalmic nerve (V1) Abducent nerve (VI) Superior ophthalmic vein

Answer 75

The deep peroneal nerve lies in the anterior muscular compartment of the lower leg and can be compromised by compartment syndrome affecting this area. It provides cutaneous sensation to the first web space. The superficial peroneal nerve provides more lateral cutaneous innervation. Deep peroneal nerve Origin From the common peroneal nerve, at the lateral aspect of the fibula, deep to peroneus longus Nerve root values L4, L5, S1, S2 Course and relation Pierces the anterior intermuscular septum to enter the anterior compartment of the lower leg Passes anteriorly down to the ankle joint, midway between the two malleoli Terminates In the dorsum of the foot Muscles innervated Tibialis anterior Extensor hallucis longus Extensor digitorum longus Peroneus tertius Extensor digitorum brevis Cutaneous innervation Web space of the first and second toes Actions Dorsiflexion of ankle joint Extension of all toes (extensor hallucis longus and extensor digitorum longus) Inversion of the foot After its bifurcation past the ankle joint, the lateral branch of the deep peroneal nerve innervates the extensor digitorum brevis and the extensor hallucis brevis The medial branch supplies the web space between the first and second digits.

Answer 76

Trapezius Nerve lesions during surgery A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 77

Abductor pollicis brevis Adductor pollicis and abductor digiti minimi are innervated by the ulnar nerve Nerve lesions during surgery A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 78

Supinator Nerve lesions during surgery A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 79

Posterior lamina of the rectus sheath An incision at this level lies below the arcuate line and the posterior wall of the rectus sheath is deficient at this level. Rectus abdominis muscle The rectus sheath is formed by the aponeuroses of the lateral abdominal wall muscles. The rectus sheath has a composition that varies according to anatomical level. 1. Above the costal margin the anterior sheath is composed of external oblique aponeurosis, the costal cartilages are posterior to it. 2. From the costal margin to the arcuate line, the anterior rectus sheath is composed of external oblique aponeurosis and the anterior part of the internal oblique aponeurosis. The posterior part of the internal oblique aponeurosis and transversus abdominis form the posterior rectus sheath. 3. Below the arcuate line the aponeuroses of all the abdominal muscles lie in anterior aspect of the rectus sheath. Posteriorly lies the transversalis fascia and peritoneum. The arcuate line is the point at which the inferior epigastric vessels enter the rectus sheath.

Answer 80

Intercostobrachial nerve The intercostobrachial nerves traverse the axilla and innervate the overlying skin. These can be injured or divided during axillary surgery and the result is anaesthesia of the overlying skin. Axilla Boundaries of the axilla Medially Chest wall and Serratus anterior Laterally Humeral head Floor Subscapularis Anterior aspect Lateral border of Pectoralis major Fascia Clavipectoral fascia Content: Long thoracic nerve (of Bell) Derived from C5-C7 and passes behind the brachial plexus to enter the axilla. It lies on the medial chest wall and supplies serratus anterior. Its location puts it at risk during axillary surgery and damage will lead to winging of the scapula. Thoracodorsal nerve and thoracodorsal trunk Innervate and vascularise latissimus dorsi. Axillary vein Lies at the apex of the axilla, it is the continuation of the basilic vein. Becomes the subclavian vein at the outer border of the first rib. Intercostobrachial nerves Traverse the axillary lymph nodes and are often divided during axillary surgery. They provide cutaneous sensation to the axillary skin. Lymph nodes The axilla is the main site of lymphatic drainage for the breast.

Answer 81

Long thoracic nerve Injury to the long thoracic nerve (which innervates the serratus anterior) can occur as it lies at the medial aspect of the axilla, winging of the scapula will then result. Axilla Boundaries of the axilla Medially Chest wall and Serratus anterior Laterally Humeral head Floor Subscapularis Anterior aspect Lateral border of Pectoralis major Fascia Clavipectoral fascia Content: Long thoracic nerve (of Bell) Derived from C5-C7 and passes behind the brachial plexus to enter the axilla. It lies on the medial chest wall and supplies serratus anterior. Its location puts it at risk during axillary surgery and damage will lead to winging of the scapula. Thoracodorsal nerve and thoracodorsal trunk Innervate and vascularise latissimus dorsi. Axillary vein Lies at the apex of the axilla, it is the continuation of the basilic vein. Becomes the subclavian vein at the outer border of the first rib. Intercostobrachial nerves Traverse the axillary lymph nodes and are often divided during axillary surgery. They provide cutaneous sensation to the axillary skin. Lymph nodes The axilla is the main site of lymphatic drainage for the breast.

Answer 82

Thoracodorsal nerve The most likely explanation for this is that the thoracodorsal nerve has been injured. This will result in atrophy of latissimus dorsi and this will become evident with repetitive arm movements where the arm is elevated and moving up and down (such as in painting). Injury to the pectoral nerves may produce a similar picture but this pattern of injury is very rare and the pectoral nerves are seldom injured in breast surgery. Axilla Boundaries of the axilla Medially Chest wall and Serratus anterior Laterally Humeral head Floor Subscapularis Anterior aspect Lateral border of Pectoralis major Fascia Clavipectoral fascia Content: Long thoracic nerve (of Bell) Derived from C5-C7 and passes behind the brachial plexus to enter the axilla. It lies on the medial chest wall and supplies serratus anterior. Its location puts it at risk during axillary surgery and damage will lead to winging of the scapula. Thoracodorsal nerve and thoracodorsal trunk Innervate and vascularise latissimus dorsi. Axillary vein Lies at the apex of the axilla, it is the continuation of the basilic vein. Becomes the subclavian vein at the outer border of the first rib. Intercostobrachial nerves Traverse the axillary lymph nodes and are often divided during axillary surgery. They provide cutaneous sensation to the axillary skin. Lymph nodes The axilla is the main site of lymphatic drainage for the breast.

Answer 83

There are six tunnels, each lined by its own synovial sheath. Extensor retinaculum The extensor rentinaculum is a thickening of the deep fascia that stretches across the back of the wrist and holds the long extensor tendons in position. Its attachments are: The pisiform and triquetral medially The end of the radius laterally Structures related to the extensor retinaculum Structures superficial to the retinaculum Basilic vein Dorsal cutaneous branch of the ulnar nerve Cephalic vein Superficial branch of the radial nerve Structures passing deep to the extensor retinaculum Extensor carpi ulnaris tendon Extensor digiti minimi tendon Extensor digitorum and extensor indicis tendon Extensor pollicis longus tendon Extensor carpi radialis longus tendon Extensor carpi radialis brevis tendon Abductor pollicis longus and extensor pollicis brevis tendons Beneath the extensor retinaculum fibrous septa form six compartments that contain the extensor muscle tendons. Each compartment has its own synovial sheath. The radial artery The radial artery passes between the lateral collateral ligament of the wrist joint and the tendons of the abductor pollicis longus and extensor pollicis brevis.

Answer 84

Adductor pollicis is innervated by the ulnar nerve. Medial two lumbricals innervated by the ulnar nerve. Median nerve The median nerve is formed by the union of a lateral and medial root respectively from the lateral (C5,6,7) and medial (C8 and T1) cords of the brachial plexus; the medial root passes anterior to the third part of the axillary artery. The nerve descends lateral to the brachial artery, crosses to its medial side (usually passing anterior to the artery). It passes deep to the bicipital aponeurosis and the median cubital vein at the elbow. It passes between the two heads of the pronator teres muscle, and runs on the deep surface of flexor digitorum superficialis (within its fascial sheath). Near the wrist it becomes superficial between the tendons of flexor digitorum superficialis and flexor carpi radialis, deep to palmaris longus tendon. It passes deep to the flexor retinaculum to enter the palm, but lies anterior to the long flexor tendons within the carpal tunnel. ``` Branches Region Branch Upper arm No branches, although the nerve commonly communicates with the musculocutaneous nerve Forearm Pronator teres Flexor carpi radialis Palmaris longus Flexor digitorum superficialis Flexor pollicis longus Flexor digitorum profundus (only the radial half) Distal forearm Palmar cutaneous branch Hand (Motor) Motor supply (LOAF) Lateral 2 lumbricals Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis Hand (Sensory) Over thumb and lateral 2 ½ fingers On the palmar aspect this projects proximally, on the dorsal aspect only the distal regions are innervated with the radial nerve providing the more proximal cutaneous innervation. ``` Patterns of damage Damage at wrist e.g. carpal tunnel syndrome paralysis and wasting of thenar eminence muscles and opponens pollicis (ape hand deformity) sensory loss to palmar aspect of lateral (radial) 2 ½ fingers Damage at elbow, as above plus: unable to pronate forearm weak wrist flexion ulnar deviation of wrist Anterior interosseous nerve (branch of median nerve) leaves just below the elbow results in loss of pronation of forearm and weakness of long flexors of thumb and index finger

Answer 85

The ureters enter the bladder at the upper lateral aspect of the base of the bladder. They are about 5cm apart from each other in the empty bladder. Internally this aspect is contained within the bladder trigone. Ureter 25-35 cm long Muscular tube lined by transitional epithelium Surrounded by thick muscular coat. Becomes 3 muscular layers as it crosses the bony pelvis Retroperitoneal structure overlying transverse processes L2-L5 Lies anterior to bifurcation of iliac vessels Blood supply is segmental; renal artery, aortic branches, gonadal branches, common iliac and internal iliac Lies beneath the uterine artery

Answer 86

The circumflex scapular artery is a branch of the subscapular artery and normally supplies the muscle on the dorsal aspect of the scapula. In this instance, flow is reversed in the circumflex scapular and subscapular arteries forming a collateral circulation around the scapula. It's an easy question really, we just made the wording difficult (on purpose). It is asking about the branches of the axillary artery and knowledge of the fact that there is an extensive collateral network around the shoulder joint. As a result, the occlusion of the proximal aspect of the circumflex humeral inflow (from the axillary artery) ceases and there is then retrograde flow through it from collaterals. Axillary artery The axillary artery extends from the outer border of the first rib to the lower border of teres major, where it becomes the brachial artery. The vessel is subdivided into three zones; the first part lies above pectoralis minor, the second part is behind the muscle and the third part lies inferior to it. First part Together with the axillary vein, the artery is enclosed within the cords of the brachial plexus. Both vessels are contained within the axillary sheath, a prolongation of the prevertebral fascia. Posteriomedial to the sheath lies the first intercostal space, the superior aspect of the serratus anterior and the long thoracic nerve. Within the sheath, the medial cord of the brachial plexus lies behind the artery. Anteriorly lies the clavipectoral fascia. Superolaterally, lie the lateral and posterior cords of the brachial plexus. Inferomedially lies the axillary vein. Second part Posterior to the second part lies the posterior cord of the brachial plexus and the subscapularis muscle. Anteriorly, lie pectoralis minor and major. The lateral cord of the brachial plexus lies laterally. Medially, lies the medial cord of the brachial plexus, here it separates the artery from the vein. Third part Posterior to the artery lie suscapularis, latissimus dorsi and teres major. Interspersed between the vessel and subscapularis are the axillary and radial nerves. Anterior to the vessel is the medial root of the median nerve. Laterally, the lies the median and musculocutaneous nerves and coracobrachialis. The axillary vein is related medially. ``` Branches of the axillary artery Highest thoracic artery Thoraco-acromial artery Lateral thoracic artery Subscapular artery Posterior circumflex humeral artery Anterior circumflex humeral artery ```

Answer 87

Obturator nerve The cutaneous branch of the obturator nerve is frequently absent. However, the obturator nerve is a recognised contributor to innervation of the medial thigh and large pelvic tumours may compress this nerve with resultant pain radiating distally. The obturator nerve arises from L2, L3 and L4 by branches from the ventral divisions of each of these nerve roots. L3 forms the main contribution and the second lumbar branch is occasionally absent. These branches unite in the substance of psoas major, descending vertically in its posterior part to emerge from its medial border at the lateral margin of the sacrum. It then crosses the sacroiliac joint to enter the lesser pelvis, it descends on obturator internus to enter the obturator groove. In the lesser pelvis the nerve lies lateral to the internal iliac vessels and ureter, and is joined by the obturator vessels lateral to the ovary or ductus deferens. Supplies Medial compartment of thigh Muscles supplied: external obturator, adductor longus, adductor brevis, adductor magnus (not the lower part-sciatic nerve), gracilis The cutaneous branch is often absent. When present, it passes between gracilis and adductor longus near the middle part of the thigh, and supplies the skin and fascia of the distal two thirds of the medial aspect. Obturator canal Connects the pelvis and thigh: contains the obturator artery, vein, nerve which divides into anterior and posterior branches.

Answer 88

The lingual nerve is closely related to the third molar and up to 10% of patients undergoing surgical extraction of these teeth may subsequently develop a lingual neuropraxia. The result is anaesthesia of the ipsilateral anterior aspect of the tongue. The inferior alveolar nerve innervates the teeth themselves. Lingual nerve Sensory nerve to the mucosa of the presulcal part of the tongue, floor of mouth and mandibular lingual gingivae Arises from posterior trunk of the mandibular nerve (branch of trigeminal) Course runs past tensor veli palatini and lateral pterygoid (where it is joined by the chorda tympani branch of the facial nerve). Emerging from the cover of the lateral pterygoid it proceeds antero inferiorly lying on the surface of the medial pterygoid and lies close to the medial aspect of the mandibular ramus. At the junction of the vertical and horizontal rami of the mandible it is anterior to the inferior alveolar nerve. It then passes below the mandibular attachment of the superior pharyngeal constrictor. Eventually, it lies on the periosteum of the root of the third molar tooth. It then passes medial to the mandibular origin of mylohyoid and then passes forwards on the inferior surface of this muscle

Answer 89

The central perineal tendon provides the main structural support to the uterus. Damage to this structure is commonly associated with the development of pelvic organ prolapse, even when other structures are intact. Uterus The non pregnant uterus resides entirely within the pelvis. The peritoneum invests the uterus and the structure is contained within the peritoneal cavity. The blood supply to the uterine body is via the uterine artery (branch of the internal iliac). The uterine artery passes from the inferior aspect of the uterus (lateral to the cervix) and runs alongside the uterus. It frequently anastomoses with the ovarian artery superiorly. Inferolaterally the ureter is a close relation and ureteric injuries are a recognised complication when pathology brings these structures into close proximity. The supports of the uterus include the central perineal tendon (the most important). The lateral cervical, round and uterosacral ligaments are condensations of the endopelvic fascia and provide additional structural support.

Answer 90

The inferior parathyroid is a derivative of the third pharyngeal pouch. The superior parathyroid originates from the fourth pharyngeal pouch. Parathyroid glands- anatomy Four parathyroid glands Located posterior to the thyroid gland They lie within the pretracheal fascia Embryology The parathyroids develop from the extremities of the third and fourth pharyngeal pouches. The parathyroids derived from the fourth pharyngeal pouch are located more superiorly and are associated with the thyroid gland. Those derived from the third pharyngeal pouch lie more inferiorly and may become associated with the thymus. Blood supply The blood supply to the parathyroid glands is derived from the inferior and superior thyroid arteries[1]. There is a rich anastomosis between the two vessels. Venous drainage is into the thyroid veins. ``` Relations Laterally Common carotid Medially Recurrent laryngeal nerve, trachea Anterior Thyroid Posterior Pretracheal fascia ```

Answer 91

Claw like appearance of the hand Injury to the ulnar nerve in the mid to distal forearm will typically produce a claw hand. This consists of flexion of the 4th and 5th interphalangeal joints and extension of the metacarpophalangeal joints. The effects are potentiated when flexor digitorum profundus is not affected, and the clawing is more pronounced.More proximally sited ulnar nerve lesions produce a milder clinical picture owing to the simultaneous paralysis of flexor digitorum profundus (ulnar half). This is the 'ulnar paradox', due to the more proximal level of transection the hand will typically not have a claw like appearance that may be seen following a more distal injury. The first dorsal interosseous muscle will be affected as it is supplied by the ulnar nerve. Effects of injury Damage at the wrist Wasting and paralysis of intrinsic hand muscles (claw hand) Wasting and paralysis of hypothenar muscles Loss of sensation medial 1 and half fingers Damage at the elbow Radial deviation of the wrist Clawing less in 4th and 5th digits Ulnar nerve Origin C8, T1 ``` Supplies (no muscles in the upper arm) Flexor carpi ulnaris Flexor digitorum profundus Flexor digiti minimi Abductor digiti minimi Opponens digiti minimi Adductor pollicis Interossei muscle Third and fourth lumbricals Palmaris brevis ``` Path Posteromedial aspect of upper arm to flexor compartment of forearm, then along the ulnar. Passes beneath the flexor carpi ulnaris muscle, then superficially through the flexor retinaculum into the palm of the hand.

Answer 92

Nerves at risk during a carotid endarterectomy: Hypoglossal nerve Greater auricular nerve Superior laryngeal nerve During a carotid endarterectomy the sternocleidomastoid muscle is dissected, with ligation of the common facial vein and then the internal jugular is dissected exposing the common and the internal carotid arteries. The nerves at risk during the operation include: Hypoglossal nerve Greater auricular nerve Superior laryngeal nerve The sympathetic chain lies posteriorly and is less prone to injury in this procedure. The internal carotid artery is formed from the common carotid opposite the upper border of the thyroid cartilage. It extends superiorly to enter the skull via the carotid canal. From the carotid canal it then passes through the cavernous sinus, above which it divides into the anterior and middle cerebral arteries. ``` Relations in the carotid canal Internal carotid plexus Cochlea and middle ear cavity Trigeminal ganglion (superiorly) Leaves canal lies above the foramen lacerum ``` Path and relations in the cranial cavity The artery bends sharply forwards in the cavernous sinus, the aducens nerve lies close to its inferolateral aspect. The oculomotor, trochlear, opthalmic and, usually, the maxillary nerves lie in the lateral wall of the sinus. Near the superior orbital fissure it turns posteriorly and passes postero-medially to pierce the roof of the cavernous sinus inferior to the optic nerve. It then passes between the optic and oculomotor nerves to terminate below the anterior perforated substance by dividing into the anterior and middle cerebral arteries. ``` Branches Anterior and middle cerebral artery Ophthalmic artery Posterior communicating artery Anterior choroid artery Meningeal arteries Hypophyseal arteries ```

Answer 93

The head of the radius articulates with the capitulum of the humerus. Radius The radius is one of the two long forearm bones that extends from the lateral side of the elbow to the thumb side of the wrist. It has two expanded ends, of which the distal end is the larger. Key points relating to its topography and relations are outlined below; Upper end Articular cartilage- covers medial > lateral side Articulates with radial notch of the ulna by the annular ligament Muscle attachment- biceps brachii at the tuberosity ``` Shaft Muscle attachment Upper third of the body Supinator Flexor digitorum superficialis Flexor pollicis longus Middle third of the body Pronator teres Lower quarter of the body Pronator quadratus Tendon of supinator longus ``` ``` Lower end Quadrilateral Anterior surface- capsule of wrist joint Medial surface- head of ulna Lateral surface- ends in the styloid process Posterior surface: 3 grooves containing: 1. Tendons of extensor carpi radialis longus and brevis 2. Tendon of extensor pollicis longus 3. Tendon of extensor indicis ```

Answer 94

Sibson's fascia overlies the apices of both lungs The suprapleural fascia (Sibson's fascia) runs from C7 to the first rib and overlies the apex of both lungs.It lies between the parietal pleura and the thoracic cage. Lung anatomy The right lung is composed of 3 lobes divided by the oblique and transverse fissures. The left lung has two lobes divided by the oblique fissure.The apex of both lungs is approximately 4cm superior to the sterno-costal joint of the first rib. Immediately below this is a sulcus created by the subclavian artery. Peripheral contact points of the lung Base: diaphragm Costal surface: corresponds to the cavity of the chest Mediastinal surface: Contacts the mediastinal pleura. Has the cardiac impression. Above and behind this concavity is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These structures are invested by pleura, which, below the hilum and behind the pericardial impression, forms the pulmonary ligament Right lung Above the hilum is the azygos vein; Superior to this is the groove for the superior vena cava and right innominate vein; behind this, and nearer the apex, is a furrow for the innominate artery. Behind the hilum and the attachment of the pulmonary ligament is a vertical groove for the oesophagus; In front and to the right of the lower part of the oesophageal groove is a deep concavity for the extrapericardiac portion of the inferior vena cava. The root of the right lung lies behind the superior vena cava and the right atrium, and below the azygos vein. The right main bronchus is shorter, wider and more vertical than the left main bronchus and therefore the route taken by most foreign bodies. Image sourced from Wikipedia Left lung Above the hilum is the furrow produced by the aortic arch, and then superiorly the groove accommodating the left subclavian artery; Behind the hilum and pulmonary ligament is a vertical groove produced by the descending aorta, and in front of this, near the base of the lung, is the lower part of the oesophagus. The root of the left lung passes under the aortic arch and in front of the descending aorta. Image sourced from Wikipedia ``` Inferior borders of both lungs 6th rib in mid clavicular line 8th rib in mid axillary line 10th rib posteriorly The pleura runs two ribs lower than the corresponding lung level. ```

Answer 95

The terminal part of the thoracic duct crosses anterior to it to insert into the right subclavian vein Internal jugular vein Each jugular vein begins in the jugular foramen, where they are the continuation of the sigmoid sinus. They terminate at the medial end of the clavicle where they unite with the subclavian vein. The vein lies within the carotid sheath throughout its course. Below the skull the internal carotid artery and last four cranial nerves are anteromedial to the vein. Thereafter it is in contact medially with the internal (then common) carotid artery. The vagus lies posteromedially. At its superior aspect, the vein is overlapped by sternocleidomastoid and covered by it at the inferior aspect of the vein. Below the transverse process of the atlas it is crossed on its lateral side by the accessory nerve. At its mid point it is crossed by the inferior root of the ansa cervicalis. Posterior to the vein are the transverse processes of the cervical vertebrae, the phenic nerve as it descends on the scalenus anterior, and the first part of the subclavian artery. On the left side its also related to the thoracic duct.

Answer 96

It lies on its radial side In the middle of the forearm, the artery is overlapped by the flexor carpi ulnaris and on the flexor retinaculum it is covered by a superficial layer from that structure. In its distal two-thirds, flexor digitorum superficialis lies on its radial side, and the ulnar nerve is situated on its ulnar side. Ulnar artery Path Starts: middle of antecubital fossa Passes obliquely downward, reaching the ulnar side of the forearm at a point about midway between the elbow and the wrist. It follows the ulnar border to the wrist, crossing over the flexor retinaculum. It then divides into the superficial and deep volar arches. Relations Deep to- Pronator teres, Flexor carpi radialis, Palmaris longus Lies on- Brachialis and Flexor digitorum profundus Superficial to the flexor retinaculum at the wrist The median nerve is in relation with the medial side of the artery for about 2.5 cm. And then crosses the vessel, being separated from it by the ulnar head of the Pronator teres The ulnar nerve lies medially to the lower two-thirds of the artery Branch Anterior interosseous artery

Answer 97

The radial nerve lies in this groove and may be compromised by fractures involving the shaft. Humerus The humerus extends from the scapula to the elbow joint. It has a body and two ends. It is almost completely covered with muscle but can usually be palpated throughout its length. The smooth rounded surface of the head articulates with the shallow glenoid cavity. The head is connected to the body of the humerus by the anatomical neck. The surgical neck is the region below the head and tubercles and where they join the shaft and is the commonest site of fracture. The capsule of the shoulder joint is attached to the anatomical neck superiorly but extends down to 1.5cm on the surgical neck. The greater tubercle is the prominence on the lateral side of the upper end of the bone. It merges with the body below and can be felt through the deltoid inferior to the acromion. The tendons of the supraspinatus and infraspinatus are inserted into impressions on its superior aspect. The lesser tubercle is a distinct prominence on the front of the upper end of the bone. It can be palpated through the deltoid just lateral to the tip of the coracoid process. The intertubercular groove passes on the body between the greater and lesser tubercles, continuing down from the anterior borders of the tubercles to form the edges of the groove. The tendon of biceps within its synovial sheath passes through this groove, held within it by a transverse ligament. The posterior surface of the body is marked by a spiral groove for the radial nerve which runs obliquely across the upper half of the body to reach the lateral border below the deltoid tuberosity. Within this groove lie the radial nerve and brachial vessels and both may be affected by fractures involving the shaft of the humerus. The lower end of the humerus is wide and flattened anteroposteriorly, and inclined anteriorly. The middle third of the distal edge forms the trochlea. Superior to this are indentations for the coronoid fossa anteriorly and olecranon fossa posteriorly. Lateral to the trochlea is a rounded capitulum which articulates with the radius. The medial epicondyle is very prominent with a smooth posterior surface which contains a sulcus for the ulnar nerve and collateral vessels. It's distal margin gives attachment for the ulnar collateral ligament and, in front of this, the anterior surface has an impression for the common flexor tendon.

Answer 98

The blood supply to the scaphoid enters from a small non articular surface near its distal end. Transverse fractures through the scaphoid therefore carry a risk of non union. Scaphoid bone The scaphoid has a concave articular surface for the head of the capitate and at the edge of this is a crescentic surface for the corresponding area on the lunate. Proximally, it has a wide convex articular surface with the radius. It has a distally sited tubercle that can be palpated. The remaining articular surface is to the lateral side of the tubercle. It faces laterally and is associated with the trapezium and trapezoid bones. The narrow strip between the radial and trapezial surfaces and the tubercle gives rise to the radial collateral carpal ligament. The tubercle receives part of the flexor retinaculum. This area is the only part of the scaphoid that is available for the entry of blood vessels. It is commonly fractured and avascular necrosis may result.

Answer 99

Glottic The vocal cords have no lymphatic drainage and therefore this region serves as a lymphatic watershed. The supraglottic part drains to the upper deep cervical nodes through vessels piercing the thyrohyoid membrane. The sub glottic part drains to the pre laryngeal, pre tracheal and inferior deep cervical nodes. The aryepiglottic and vestibular folds have a rich lymphatic drainage and will metastasise early. Larynx The larynx lies in the anterior part of the neck at the levels of C3 to C6 vertebral bodies. The laryngeal skeleton consists of a number of cartilagenous segments. Three of these are paired; arytenoid, corniculate and cuneiform. Three are single; thyroid, cricoid and epiglottic. The cricoid cartilage forms a complete ring (the only one to do so). The laryngeal cavity extends from the laryngeal inlet to the level of the inferior border of the cricoid cartilage. Divisions of the laryngeal cavity Laryngeal vestibule Superior to the vestibular folds Laryngeal ventricle Lies between vestibular folds and superior to the vocal cords Infraglottic cavity Extends from vocal cords to inferior border of the cricoid cartilage The vocal folds (true vocal cords) control sound production. The apex of each fold projects medially into the laryngeal cavity. Each vocal fold includes: Vocal ligament Vocalis muscle (most medial part of thyroarytenoid muscle) The glottis is composed of the vocal folds, processes and rima glottidis. The rima glottidis is the narrowest potential site within the larynx, as the vocal cords may be completely opposed, forming a complete barrier. Blood supply Arterial supply is via the laryngeal arteries, branches of the superior and inferior thyroid arteries. The superior laryngeal artery is closely related to the internal laryngeal nerve. The inferior laryngeal artery is related to the inferior laryngeal nerve. Venous drainage is via superior and inferior laryngeal veins, the former draining into the superior thyroid vein and the latter draining into the middle thyroid vein, or thyroid venous plexus. Lymphatic drainage The vocal cords have no lymphatic drainage and this site acts as a lymphatic watershed. Supraglottic part Upper deep cervical nodes Subglottic part Prelaryngeal and pretracheal nodes and inferior deep cervical nodes The aryepiglottic fold and vestibular folds have a dense plexus of lymphatics associated with them and malignancies at these sites have a greater propensity for nodal metastasis.

Answer 100

There are 4 collateral venous systems: Azygos venous system Internal mammary venous pathway Long thoracic venous system with connections to the femoral and vertebral veins (2 pathways) Despite this, venous hypertension still occurs. Superior vena cava ``` Drainage Head and neck Upper limbs Thorax Part of abdominal walls ``` Formation Subclavian and internal jugular veins unite to form the right and left brachiocephalic veins These unite to form the SVC Azygos vein joins the SVC before it enters the right atrium

Answer 101

The anterior interosseous nerve is a branch of the median nerve and is responsible for innervation of the lateral aspect of the flexor digitorum profundus. Flexor digitorum profundus originates in the upper 3/4 of the anterior and medial surfaces of the ulna, interosseous membrane and deep fascia of the forearm. The muscle fans out into four tendons (one to each of the second to fifth fingers) to the palmar base of the distal phalanx. Along with the flexor digitorum superficialis, it has long tendons that run down the arm and through the carpal tunnel and attach to the palmar side of the phalanges of the fingers. Flexor digitorum profundus lies deep to the superficialis, but it attaches more distally. Therefore, profundus's tendons go through the tendons of superficialis, and end up attaching to the distal phalanx. For this reason profundus is also called the perforating muscle.[1] The lumbricals of the hand arise from the radial side of its tendons.[1] Nerve supply[edit] Flexor digitorum profundus is a composite muscle innervated by the anterior interosseous nerve and ulnar nerves. The medial aspect of the muscle (which flexes the 4th and 5th digit) is supplied by the ulnar nerve (C8, T1)[2] The lateral aspect (which flexes the 2nd and 3rd digit) is innervated by the median nerve[2] specifically the anterior interosseous branch (C8, T1). It is one of two flexor muscles that is not exclusively supplied by the median nerve (the other is flexor carpi ulnaris).

Answer 102

Should the strap muscles require division during surgery they should be divided in their upper half. This is because their nerve supply from the ansa cervicalis enters in their lower half. Anterior triangle of the neck Boundaries Anterior border of the Sternocleidomastoid Lower border of mandible Anterior midline Sub triangles (divided by Digastric above and Omohyoid) Muscular triangle: Neck strap muscles Carotid triangle: Carotid sheath Submandibular Triangle (digastric) Nerve supply to digastric muscle Anterior: Mylohyoid nerve Posterior: Facial nerve

Answer 103

Damage to the vagus Many of these nerves are at risk of injury during carotid surgery. However, only damage to the vagus would account for a hoarse voice. Vagus nerve The vagus nerve has mixed functions and supplies the structures from the fourth and sixth pharyngeal arches. It also supplies the fore and midgut sections of the embryonic gut tube. It carries afferent fibres from these areas (viz; pharynx, larynx, oesophagus, stomach, lungs, heart and great vessels). The efferent fibres of the vagus are of two main types. The first are preganglionic parasympathetic fibres distributed to the parasympathetic ganglia that innervate smooth muscle of the innervated organs (such as gut). The second type of efferent fibres have direct skeletal muscle innervation, these are largely to the muscles of the larynx and pharynx. Origin and course The vagus arises from the lateral surface of the medulla oblongata by a series of rootlets. It is related to the glossopharyngeal nerve cranially and the accessory nerve caudally. It exits through the jugular foramen and is contained within its own dural sheath alongside the accessory nerve. In the neck it descends vertically in the carotid sheath where it is closely related to the internal and common carotid arteries. It leaves the neck and enters the mediastinum. On the right it passes anterior to the first part of the subclavian artery, on the left it lies in the interval between the common carotid and subclavian arteries. In the mediastinum both nerves pass postero-inferiorly and reach the posterior surface of the corresponding lung root. These then branch into both lungs. At the inferior end of the mediastinum these plexuses reunite to form the formal vagal trunks that pass through the oesophageal hiatus and into the abdomen. The anterior and posterior vagal trunks are formal nerve fibres these then splay out once again sending fibres over the stomach and posteriorly to the coeliac plexus. Branches pass to the liver, spleen and kidney.

Answer 104

The subclavian vein lies behind subclavius and the medial part of the clavicle. It rests on the first rib, below and in front of the third part of the subclavian artery, and then on scalenus anterior which separates it from the second part of the artery (posteriorly). Clavicle The clavicle extends from the sternum to the acromion and helps prevent the shoulder falling forwards and downwards. The inferior surface is irregular and strongly marked by ligaments at each end. Laterally, lies the trapezoid line and this runs anterolaterally. Posteriorly, lies the conoid tubercle. These give attachment to the conoid and trapezoid parts of the coracoclavicular ligament. The medial part of the inferior surface has an irregular surface which marks the surface attachment of the costoclavicular ligament. The intermediate portion is marked by a groove for the subclavius muscle. Medially, the superior part of the bone has a raised surface which gives attachment to the clavicular head of sternocleidomastoid. Sternohyoid gains attachment to the posterior surface. Laterally there is an oval articular facet for the acromion and a disk lies between the clavicle and acromion. The capsule of the joint is attached to the ridge on the margin of the facet.

Answer 105

The lateral aspect of the external nose is innervated by lateral nasal branches of the anterior ethmoidal nerve. The ethmoidal nerve is a branch of the nasociliary nerve which is one of the divisions of the trigeminal. Path Originates at the pons Sensory root forms the large, crescentic trigeminal ganglion within Meckel's cave, and contains the cell bodies of incoming sensory nerve fibres. Here the 3 branches exit. The motor root cell bodies are in the pons and the motor fibres are distributed via the mandibular nerve. The motor root is not part of the trigeminal ganglion. Branches of the trigeminal nerve Ophthalmic nerve Sensory only Maxillary nerve Sensory only Mandibular nerve Sensory and motor Sensory Ophthalmic Exits skull via the superior orbital fissure Sensation of: scalp and forehead, the upper eyelid, the conjunctiva and cornea of the eye, the nose (including the tip of the nose, except alae nasi), the nasal mucosa, the frontal sinuses, and parts of the meninges (the dura and blood vessels). Maxillary nerve Exit skull via the foramen rotundum Sensation: lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges. Mandibular nerve Exit skull via the foramen ovale Sensation: lower lip, the lower teeth and gums, the chin and jaw (except the angle of the jaw), parts of the external ear, and parts of the meninges. ``` Motor Distributed via the mandibular nerve. The following muscles of mastication are innervated: Masseter Temporalis Medial pterygoid Lateral pterygoid ``` ``` Other muscles innervated include: Tensor veli palatini Mylohyoid Anterior belly of digastric Tensor tympani ```

Answer 106

The pleural reflections encase the hilum of the lung and continue inferiorly as the pulmonary ligament. It encases the pulmonary vessels and bronchus. The azygos vein is not contained within it. The right lung is composed of 3 lobes divided by the oblique and transverse fissures. The left lung has two lobes divided by the oblique fissure.The apex of both lungs is approximately 4cm superior to the sterno-costal joint of the first rib. Immediately below this is a sulcus created by the subclavian artery. Peripheral contact points of the lung Base: diaphragm Costal surface: corresponds to the cavity of the chest Mediastinal surface: Contacts the mediastinal pleura. Has the cardiac impression. Above and behind this concavity is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These structures are invested by pleura, which, below the hilum and behind the pericardial impression, forms the pulmonary ligament Right lung Above the hilum is the azygos vein; Superior to this is the groove for the superior vena cava and right innominate vein; behind this, and nearer the apex, is a furrow for the innominate artery. Behind the hilum and the attachment of the pulmonary ligament is a vertical groove for the oesophagus; In front and to the right of the lower part of the oesophageal groove is a deep concavity for the extrapericardiac portion of the inferior vena cava. The root of the right lung lies behind the superior vena cava and the right atrium, and below the azygos vein. The right main bronchus is shorter, wider and more vertical than the left main bronchus and therefore the route taken by most foreign bodies. Left lung Above the hilum is the furrow produced by the aortic arch, and then superiorly the groove accommodating the left subclavian artery; Behind the hilum and pulmonary ligament is a vertical groove produced by the descending aorta, and in front of this, near the base of the lung, is the lower part of the oesophagus. The root of the left lung passes under the aortic arch and in front of the descending aorta. Inferior borders of both lungs 6th rib in mid clavicular line 8th rib in mid axillary line 10th rib posteriorly The pleura runs two ribs lower than the corresponding lung level.

Answer 107

The lesser omentum will need to be divided. During a radical gastrectomy this forms one of the nodal stations that will need to be taken. Coeliac axis The coeliac axis has three main branches. Left gastric Hepatic: branches-Right Gastric, Gastroduodenal, Superior Pancreaticoduodenal, Cystic (occasionally). Splenic: branches- Pancreatic, Short Gastric, Left Gastroepiploic

Answer 108

The sympathetic chain lies posterior to the parietal pleura. During a thorascopic sympathetomy this structure will need to be divided. The intercostal vessels lie posteriorly. They may be damaged with troublesome bleeding but otherwise are best left alone as deliberate division will not improve surgical access. Sympathetic nervous system- anatomy The cell bodies of the pre-ganglionic efferent neurones lie in the lateral horn of the grey matter of the spinal cord in the thoraco-lumbar regions. The pre-ganglionic efferents leave the spinal cord at levels T1-L2. These pass to the sympathetic chain. Lateral branches of the sympathetic chain connect it to every spinal nerve. These post ganglionic nerves will pass to structures that receive sympathetic innervation at the periphery. Sympathetic chains These lie on the vertebral column and run from the base of the skull to the coccyx. Cervical region Lie anterior to the transverse processes of the cervical vertebrae and posterior to the carotid sheath. Thoracic region Lie anterior to the neck of the upper ribs and and lateral sides of the lower thoracic vertebrae.They are covered by the parietal pleura Lumbar region Enter by passing posterior to the medial arcuate ligament. Lie anteriorly to the vertebrae and medial to psoas major. Sympathetic ganglia Superior cervical ganglion lies anterior to C2 and C3. Middle cervical ganglion (if present) C6 Stellate ganglion- anterior to transverse process of C7, lies posterior to the subclavian artery, vertebral artery and cervical pleura. Thoracic ganglia are segmentally arranged. There are usually 4 lumbar ganglia. Clinical importance Interruption of the head and neck supply of the sympathetic nerves will result in an ipsilateral Horners syndrome. For treatment of hyperhidrosis the sympathetic denervation can be achieved by removing the second and third thoracic ganglia with their rami. Removal of T1 will cause a Horners syndrome and is therefore not performed. In patients with vascular disease of the lower limbs a lumbar sympathetomy may be performed, either radiologically or (more rarely now) surgically. The ganglia of L2 and below are disrupted. If L1 is removed then ejaculation may be compromised (and little additional benefit conferred as the preganglionic fibres do not arise below L2.

Answer 109

The CSF flows from the 3rd to the 4th ventricle via the Aqueduct of Sylvius. Cerebrospinal fluid The CSF fills the space between the arachnoid mater and pia mater (covering surface of the brain). The total volume of CSF in the brain is approximately 150ml. Approximately 500 ml is produced by the ependymal cells in the choroid plexus (70%), or blood vessels (30%). It is reabsorbed via the arachnoid granulations which project into the venous sinuses. Circulation 1. Lateral ventricles (via foramen of Munro) 2. 3rd ventricle 3. Cerebral aqueduct (aqueduct of Sylvius) 4. 4th ventricle (via foramina of Magendie and Luschka) 5. Subarachnoid space 6. Reabsorbed into the venous system via arachnoid granulations into superior sagittal sinus ``` Composition Glucose: 50-80mg/dl Protein: 15-40 mg/dl Red blood cells: Nil White blood cells: 0-3 cells/ mm3 ```

Answer 110

Cranial nerves carrying parasympathetic fibres X IX VII III (1973) The parasympathetic functions served by the cranial nerves include: III (oculomotor) Pupillary constriction and accommodation VII (facial) Lacrimal gland, submandibular and sublingual glands IX (glossopharyngeal) Parotid X (vagus) Heart and abdominal viscera The optic nerve carries no parasympathetic fibres. The cranial preganglionic parasympathetic nerves arise from specific nuclei in the CNS. These synapse at one of four parasympathetic ganglia; otic, pterygopalatine, ciliary and submandibular. From these ganglia the parasympathetic nerves complete their journey to their target tissues via CN V (trigeminal) branches (ophthalmic nerve CNV branch 1, Maxillary nerve CN V branch2, mandibular nerve CN V branch 3) Cranial nerve lesions Olfactory nerve May be injured in basal skull fractures or involved in frontal lobe tumour extension. Loss of olfactory nerve function in relation to major CNS pathology is seldom an isolated event and thus it is poor localiser of CNS pathology. Optic nerve Problems with visual acuity may result from intra ocular disorders. Problems with the blood supply such as amaurosis fugax may produce temporary visual distortion. More important surgically is the pupillary response to light. The pupillary size may be altered in a number of disorders. Nerves involved in the resizing of the pupil connect to the pretectal nucleus of the high midbrain, bypassing the lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurones pass to the Edinger - Westphal nucleus, motor axons from here pass along with the oculomotor nerve. They synapse with ciliary ganglion neurones; the parasympathetic axons from this then innervate the iris and produce miosis. The miotic pupil is seen in disorders such as Horner's syndrome or opiate overdose. Mydriasis is the dilatation of the pupil in response to disease, trauma, drugs (or the dark!). It is pathological when light fails to induce miosis. The radial muscle is innervated by the sympathetic nervous system. Because the parasympathetic fibres travel with the oculomotor nerve they will be damaged by lesions affecting this nerve (e.g. cranial trauma). The response to light shone in one eye is usually a constriction of both pupils. This indicates intact direct and consensual light reflexes. When the optic nerve has an afferent defect the light shining on the affected eye will produce a diminished pupillary response in both eyes. Whereas light shone on the unaffected eye will produce a normal pupillary response in both eyes. This is referred to as the Marcus Gunn pupil and is seen in conditions such as optic neuritis. In a total CN II lesion shining the light in the affected eye will produce no response. Oculomotor nerve The pupillary effects are described above. In addition it supplies all ocular muscles apart from lateral rectus and superior oblique. Thus the affected eye will be deviated inferolaterally. Levator palpebrae superioris may also be impaired resulting in impaired ability to open the eye. Trochlear nerve The eye will not be able to look down. Trigeminal nerve Largest cranial nerve. Exits the brainstem at the pons. Branches are ophthalmic, maxillary and mandibular. Only the mandibular branch has both sensory and motor fibres. Branches converge to form the trigeminal ganglion (located in Meckels cave). It supplies the muscles of mastication and also tensor veli palatine, mylohyoid, anterior belly of digastric and tensor tympani. The detailed descriptions of the various sensory functions are described in other areas of the website. The corneal reflex is important and is elicited by applying a small tip of cotton wool to the cornea, a reflex blink should occur if it is intact. It is mediated by: the naso ciliary branch of the ophthalmic branch of the trigeminal (sensory component) and the facial nerve producing the motor response. Lesions of the afferent arc will produce bilateral absent blink and lesions of the efferent arc will result in a unilateral absent blink. Abducens nerve The affected eye will have a deficit of abduction. This cranial nerve exits the brainstem between the pons and medulla. It thus has a relatively long intra cranial course which renders it susceptible to damage in raised intra cranial pressure. Facial nerve Emerges from brainstem between pons and medulla. It controls muscles of facial expression and taste from the anterior 2/3 of the tongue. The nerve passes into the petrous temporal bone and into the internal auditory meatus. It then passes through the facial canal and exits at the stylomastoid foramen. It passes through the parotid gland and divides at this point. It does not innervate the parotid gland. Its divisions are considered in other parts of the website. Its motor fibres innervate orbicularis oculi to produce the efferent arm of the corneal reflex. In surgical practice it may be injured during parotid gland surgery or invaded by malignancies of the gland and a lower motor neurone on the ipsilateral side will result. Vestibulo-cochlear nerve Exits from the pons and then passes through the internal auditory meatus. It is implicated in sensorineural hearing loss. Individuals with sensorineural hearing loss will localise the sound in webers test to the normal ear. Rinnes test will be reduced on the affected side but should still work. These two tests will distinguish sensorineural hearing loss from conductive deafness. In the latter condition webers test will localise to the affected ear and Rinnes test will be impaired on the affected side. Surgical lesions affecting this nerve include CNS tumours and basal skull fractures. It may also be damaged by the administration of ototoxic drugs (of which gentamicin is the most commonly used in surgical practice). Glossopharyngeal nerve Exits the pons just above the vagus. Receives sensory fibres from posterior 1/3 tongue, tonsils, pharynx and middle ear (otalgia may occur following tonsillectomy). It receives visceral afferents from the carotid bodies. It supplies parasympathetic fibres to the parotid gland via the otic ganglion and motor function to stylopharyngeaus muscle. The sensory function of the nerve is tested using the gag reflex. Vagus nerve Leaves the medulla between the olivary nucleus and the inferior cerebellar peduncle. Passes through the jugular foramen and into the carotid sheath. Details of the functions of the vagus nerve are covered in the website under relevant organ sub headings. Accessory nerve Exists from the caudal aspect of the brainstem (multiple branches) supplies trapezius and sternocleidomastoid muscles. The distal portion of this nerve is most prone to injury during surgical procedures. Hypoglossal nerve Emerges from the medulla at the preolivary sulcus, passes through the hypoglossal canal. It lies on the carotid sheath and passes deep to the posterior belly of digastric to supply muscles of the tongue (except palatoglossus). Its location near the carotid sheath makes it vulnerable during carotid endarterectomy surgery and damage will produce ipsilateral defect in muscle function.

Answer 111

Denticulate ligaments The spinal cord is approximately 45cm in men and 43cm in women. The denticulate ligament is a continuation of the pia mater (innermost covering of the spinal cord) which has intermittent lateral projections attaching the spinal cord to the dura mater. Spinal cord Located in a canal within the vertebral column that affords it structural support. Rostrally it continues to the medulla oblongata of the brain and caudally it tapers at a level corresponding to the L1-2 interspace (in the adult), a central structure, the filum terminale anchors the cord to the first coccygeal vertebra. The spinal cord is characterised by cervico-lumbar enlargements and these, broadly speaking, are the sites which correspond to the brachial and lumbar plexuses respectively. There are some key points to note when considering the surgical anatomy of the spinal cord: * During foetal growth the spinal cord becomes shorter than the spinal canal, hence the adult site of cord termination at the L1-2 level. * Due to growth of the vertebral column the spine segmental levels may not always correspond to bony landmarks as they do in the cervical spine. * The spinal cord is incompletely divided into two symmetrical halves by a dorsal median sulcus and ventral median fissure. Grey matter surrounds a central canal that is continuous rostrally with the ventricular system of the CNS. * The grey matter is sub divided cytoarchitecturally into Rexeds laminae. * Afferent fibres entering through the dorsal roots usually terminate near their point of entry but may travel for varying distances in Lissauers tract. In this way they may establish synaptic connections over several levels * At the tip of the dorsal horn are afferents associated with nociceptive stimuli. The ventral horn contains neurones that innervate skeletal muscle. The key point to remember when revising CNS anatomy is to keep a clinical perspective in mind. So it is worth classifying the ways in which the spinal cord may become injured. These include: Trauma either direct or as a result of disc protrusion Neoplasia either by direct invasion (rare) or as a result of pathological vertebral fracture Inflammatory diseases such as Rheumatoid disease, or OA (formation of osteophytes compressing nerve roots etc. Vascular either as a result of stroke (rare in cord) or as complication of aortic dissection Infection historically diseases such as TB, epidural abscesses. The anatomy of the cord will, to an extent dictate the clinical presentation. Some points/ conditions to remember: Brown- Sequard syndrome-Hemisection of the cord producing ipsilateral loss of proprioception and upper motor neurone signs, plus contralateral loss of pain and temperature sensation. The explanation of this is that the fibres decussate at different levels. Lesions below L1 will tend to present with lower motor neurone signs

Answer 112

The branches of the lower molar and premolar teeth are supplied by branches of the inferior alveolar nerve. Those of the canine and incisors by the incisive branch of the same nerve. The gingiva and supporting structures are innervated by the lingual nerve. Trigeminal nerve The trigeminal nerve is the main sensory nerve of the head. In addition to its major sensory role, it also innervates the muscles of mastication. ``` Distribution of the trigeminal nerve Sensory Scalp Face Oral cavity (and teeth) Nose and sinuses Dura mater Motor Muscles of mastication Mylohyoid Anterior belly of digastric Tensor tympani Tensor palati Autonomic connections (ganglia) Ciliary Sphenopalatine Otic Submandibular ``` Path Originates at the pons Sensory root forms the large, crescentic trigeminal ganglion within Meckel's cave, and contains the cell bodies of incoming sensory nerve fibres. Here the 3 branches exit. The motor root cell bodies are in the pons and the motor fibres are distributed via the mandibular nerve. The motor root is not part of the trigeminal ganglion. Branches of the trigeminal nerve Ophthalmic nerve Sensory only Maxillary nerve Sensory only Mandibular nerve Sensory and motor Sensory Ophthalmic Exits skull via the superior orbital fissure Sensation of: scalp and forehead, the upper eyelid, the conjunctiva and cornea of the eye, the nose (including the tip of the nose, except alae nasi), the nasal mucosa, the frontal sinuses, and parts of the meninges (the dura and blood vessels). Maxillary nerve Exit skull via the foramen rotundum Sensation: lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges. Mandibular nerve Exit skull via the foramen ovale Sensation: lower lip, the lower teeth and gums, the chin and jaw (except the angle of the jaw), parts of the external ear, and parts of the meninges. ``` Motor Distributed via the mandibular nerve. The following muscles of mastication are innervated: Masseter Temporalis Medial pterygoid Lateral pterygoid ``` ``` Other muscles innervated include: Tensor veli palatini Mylohyoid Anterior belly of digastric Tensor tympani ```

Answer 113

The ansa cervicalis lies anterior to the carotid sheath. It may be exposed by division of the pretracheal fascia at the posterolateral aspect of the thyroid gland. The pre vertebral fascia lies more posteriorly and division of the investing layer of fascia will not expose this nerve. The ansa cervicalis lies anterior to the carotid sheath. The nerve supply to the inferior strap muscles enters at their inferior aspect. Therefore when dividing these muscles to expose a large goitre, the muscles should be divided in their upper half.

Answer 114

The iliacus lies posterior to the femoral nerve in the femoral triangle. The femoral sheath lies anterior to the iliacus and pectineus muscles. Femoral nerve ``` Root values L2, 3, 4 Innervates Pectineus Sartorius Quadriceps femoris Vastus lateralis/medialis/intermedius Branches Medial cutaneous nerve of thigh Saphenous nerve Intermediate cutaneous nerve of thigh ``` Path Penetrates psoas major and exits the pelvis by passing under the inguinal ligament to enter the femoral triangle, lateral to the femoral artery and vein. Mnemonic for femoral nerve supply (don't) M I S V Q Scan for PE M edial cutaneous nerve of the thigh I ntermediate cutaneous nerve of the thigh S aphenous nerve V astus Q uadriceps femoris S artorius PE ectineus

Answer 115

Inferior vena cava It drains directly via a very short vessel. If the sutures are not carefully tied then it may be avulsed off the IVC. An injury best managed using a Satinsky clamp and a 6/0 prolene suture. Adrenal gland anatomy Anatomy Location Superomedially to the upper pole of each kidney Relationships of the right adrenal Diaphragm-Posteriorly, Kidney-Inferiorly, Vena Cava-Medially, Hepato-renal pouch and bare area of the liver-Anteriorly Relationships of the left adrenal Crus of the diaphragm-Postero- medially, Pancreas and splenic vessels-Inferiorly, Lesser sac and stomach-Anteriorly Arterial supply Superior adrenal arteries- from inferior phrenic artery, Middle adrenal arteries - from aorta, Inferior adrenal arteries -from renal arteries Venous drainage of the right adrenal Via one central vein directly into the IVC Venous drainage of the left adrenal Via one central vein into the left renal vein

Answer 116

During splenectomy the tail of the pancreas may be damaged. The pancreatic duct will then drain into the splenic bed, amylase is the most likely biochemical finding. Glucagon is not secreted into the pancreatic duct. Splenic anatomy The spleen is the largest lymphoid organ in the body. It is an intraperitoneal organ, the peritoneal attachments condense at the hilum where the vessels enter the spleen. Its blood supply is from the splenic artery (derived from the coeliac axis) and the splenic vein (which is joined by the IMV and unites with the SMV). Embryology: derived from mesenchymal tissue Shape: clenched fist Position: below 9th-12th ribs Weight: 75-150g Relations Superiorly- diaphragm Anteriorly- gastric impression Posteriorly- kidney Inferiorly- colon Hilum: tail of pancreas and splenic vessels Forms apex of lesser sac (containing short gastric vessels)

Answer 117

Winging of the scapula is most commonly the result of long thoracic nerve injury or dysfunction. Iatrogenic damage during the course of the difficult axillary dissection is the most likely cause in this scenario. Damage to the rhomboids may produce winging of the scapula but would be rare in the scenario given. Long thoracic nerve Derived from ventral rami of C5, C6, and C7 (close to their emergence from intervertebral foramina) It runs downward and passes either anterior or posterior to the middle scalene muscle It reaches upper tip of serratus anterior muscle and descends on outer surface of this muscle, giving branches into it Winging of Scapula occurs in long thoracic nerve injury (most common) or from spinal accessory nerve injury (which denervates the trapezius) or a dorsal scapular nerve injury

Answer 118

Laceration of the middle meningeal artery Head injury Patients who suffer head injuries should be managed according to ATLS principles and extra cranial injuries should be managed alongside cranial trauma. Inadequate cardiac output will compromise CNS perfusion irrespective of the nature of the cranial injury. Types of traumatic brain injury Extradural haematoma Bleeding into the space between the dura mater and the skull. Often results from acceleration-deceleration trauma or a blow to the side of the head. The majority of extradural haematomas occur in the temporal region where skull fractures cause a rupture of the middle meningeal artery. Features Raised intracranial pressure Some patients may exhibit a lucid interval Subdural haematoma Bleeding into the outermost meningeal layer. Most commonly occur around the frontal and parietal lobes. May be either acute or chronic. Risk factors include old age and alcoholism. Slower onset of symptoms than a extradural haematoma. Subarachnoid haemorrhage Usually occurs spontaneously in the context of a ruptured cerebral aneurysm, but may be seen in association with other injuries when a patient has sustained a traumatic brain injury. Pathophysiology Primary brain injury may be focal (contusion/ haematoma) or diffuse (diffuse axonal injury) Diffuse axonal injury occurs as a result of mechanical shearing following deceleration, causing disruption and tearing of axons Intra-cranial haematomas can be extradural, subdural or intracerebral, while contusions may occur adjacent to (coup) or contralateral (contre-coup) to the side of impact Secondary brain injury occurs when cerebral oedema, ischaemia, infection, tonsillar or tentorial herniation exacerbates the original injury. The normal cerebral auto regulatory processes are disrupted following trauma rendering the brain more susceptible to blood flow changes and hypoxia The Cushings reflex (hypertension and bradycardia) often occurs late and is usually a pre terminal event Management Where there is life threatening rising ICP such as in extra dural haematoma and whilst theatre is prepared or transfer arranged use of IV mannitol/ frusemide may be required. Diffuse cerebral oedema may require decompressive craniotomy Exploratory Burr Holes have little management in modern practice except where scanning may be unavailable and to thus facilitate creation of formal craniotomy flap Depressed skull fractures that are open require formal surgical reduction and debridement, closed injuries may be managed non operatively if there is minimal displacement. ICP monitoring is appropriate in those who have GCS 3-8 and normal CT scan. ICP monitoring is mandatory in those who have GCS 3-8 and abnormal CT scan. Hyponatraemia is most likely to be due to syndrome of inappropriate ADH secretion. Minimum of cerebral perfusion pressure of 70mmHg in adults. Minimum cerebral perfusion pressure of between 40 and 70 mmHg in children.

Answer 119

The tunica vaginalis is derived from peritoneum, it secretes the fluid that fills the hydrocele cavity. Spermatic cord Formed by the vas deferens and is covered by the following structures: Layer Origin Internal spermatic fascia Transversalis fascia Cremasteric fascia From the fascial coverings of internal oblique External spermatic fascia External oblique aponeurosis Scrotum Composed of skin and closely attached dartos fascia. Arterial supply from the anterior and posterior scrotal arteries Lymphatic drainage to the inguinal lymph nodes Parietal layer of the tunica vaginalis is the innermost layer Testes The testes are surrounded by the tunica vaginalis (closed peritoneal sac). The parietal layer of the tunica vaginalis adjacent to the internal spermatic fascia. The testicular arteries arise from the aorta immediately inferiorly to the renal arteries. The pampiniform plexus drains into the testicular veins, the left drains into the left renal vein and the right into the inferior vena cava. Lymphatic drainage is to the para-aortic nodes.

Answer 120

The interclavicular ligament lies at the upper end of a median sternotomy and is routinely divided to provide access. The pleural reflections are often encountered and should not be intentionally divided, if they are, then a chest drain will need to be inserted on the affected side as collections may then accumulate in the pleural cavity. Other structures encountered include the pectoralis major muscles, again if the incision is truly midline then these should not require formal division. The close relationship of the brachiocephalic vein should be borne in mind and it should be avoided, iatrogenic injury to this structure will result in considerable haemorrhage. Sternotomy A median sternotomy is the commonest incision utilised to access the heart and great vessels. A midline incision is made from the interclavicular fossa to the xiphoid process and the fat and subcutaneous tissues are divided to the level of the sternum. The periosteum may be gently mobilised off the midline, although vigorous periosteal stripping is best avoided. A bone saw is used to divide the bone itself. Posteriorly the reflections of the parietal pleura should be identified and avoided (unless surgery to the lung is planned). The fibrous pericardium is incised and the heart brought into view. Bleeding from the bony edges of the cut sternum is stopped using roller ball diathermy or bone wax. The left brachiocephalic vein is an important posterior relation at the superior aspect of the sternotomy incision and should be avoided. More inferior the thymic remnants may be identified. At the inferior aspect of the incision the abdominal cavity may be entered (though this is seldom troublesome).

Answer 121

The azygos vein is routinely divided during an oesophagectomy to allow mobilisation. It arches anteriorly to insert into the SVC on the right hand side. Treatment of oesophageal cancer In general resections are not offered to those patients with distant metastasis, and usually not to those with N2 disease. Local nodal involvement is not in itself a contra indication to resection. Surgical resection is the mainstay of treatment. Neoadjuvent chemotherapy is given in most cases prior to surgery. In situ disease may be managed by endoscopic mucosal resection, although this is still debated. In patients with lower third lesions an Ivor - Lewis type procedure is most commonly performed. Very distal tumours may be suitable to a transhiatal procedure. Which is an attractive option as the penetration of two visceral cavities required for an Ivor- Lewis type procedure increases the morbidity considerably. More proximal lesions will require a total oesphagectomy (Mckeown type) with anastomosis to the cervical oesophagus. Patients with unresectable disease may derive benefit from local ablative procedures, palliative chemotherapy or stent insertion. Operative details of Ivor- Lewis procedure Combined laparotomy and right thoracotomy Indication Lower and middle third oesophageal tumours Preparation Staging with a combination of CT chest abdomen and pelvis- if no metastatic disease detected then patients will undergo a staging laparoscopy to detect peritoneal disease. If both these modalities are negative then patients will finally undergo a PET CT scan to detect occult metastatic disease. Only in those whom no evidence of advanced disease is detected will proceed to resection. Patients receive a GA, double lumen endotracheal tube to allow for lung deflation, CVP and arterial monitoring. Procedure A rooftop incision is made to access the stomach and duodenum. Laparotomy To mobilize the stomach The greater omentum is incised away from its attachment to the right gastroepiploic vessels along the greater curvature of the stomach. Then the short gastric vessels are ligated and detached from the greater curvature from the spleen. The lesser omentum is incised, preserving the right gastric artery. The retroperitoneal attachments of the duodenum in its second and third portions are incised, allowing the pylorus to reach the oesophageal hiatus. Some surgeons perform a pyloroplasty at this point to facilitate gastric emptying. The left gastric vessels are then ligated, avoiding any injury to the common hepatic or splenic arteries. Care must be taken to avoid inadvertently devascularising the liver owing to variations in anatomy. Right Thoracotomy Oesophageal resection and oesophagogastric anastomosis Through 5th intercostal space Dissection performed 10cm above the tumour This may involve transection of the azygos vein. The oesophagus is then removed with the stomach creating a gastric tube. An anastomosis is created. The chest is closed with underwater seal drainage and tube drains to the abdominal cavity. Post operatively Patients will typically recover in ITU initially. A nasogastric tube will have been inserted intraoperatively and must remain in place during the early phases of recovery. Post operatively these patients are at relatively high risk of developing complications: * Atelectasis- due to the effects of thoracotomy and lung collapse * Anastomotic leakage. The risk is relatively high owing to the presence of a relatively devascularised stomach. Often the only blood supply is from the gastroepiploic artery as all others will have been divided. If a leak does occur then many will attempt to manage conservatively with prolonged nasogastric tube drainage and TPN. The reality is that up to 50% of patients developing an anastomotic leak will not survive to discharge. * Delayed gastric emptying (may be avoided by performing a pyloroplasty).

Answer 122

Causes flexion of the thoracic spine Quadratus lumborum Origin: Medial aspect of iliac crest and iliolumbar ligament Insertion: 12th rib Action: Pulls the rib cage inferiorly. Lateral flexion. Nerve supply: Anterior primary rami of T12 and L1-3 The rectus abdominis causes flexion of the thoracic spine and therefore the statement suggesting that quaratus lumborum does so is incorrect. Abdominal wall The 2 main muscles of the abdominal wall are the rectus abdominis (anterior) and the quadratus lumborum (posterior). The remaining abdominal wall consists of 3 muscular layers. Each muscle passes from the lateral aspect of the quadratus lumborum posteriorly to the lateral margin of the rectus sheath anteriorly. Each layer is muscular posterolaterally and aponeurotic anteriorly. Muscles of abdominal wall External oblique Lies most superficially Originates from 5th to 12th ribs Inserts into the anterior half of the outer aspect of the iliac crest, linea alba and pubic tubercle More medially and superiorly to the arcuate line, the aponeurotic layer overlaps the rectus abdominis muscle The lower border forms the inguinal ligament The triangular expansion of the medial end of the inguinal ligament is the lacunar ligament. Internal oblique Arises from the thoracolumbar fascia, the anterior 2/3 of the iliac crest and the lateral 2/3 of the inguinal ligament The muscle sweeps upwards to insert into the cartilages of the lower 3 ribs The lower fibres form an aponeurosis that runs from the tenth costal cartilage to the body of the pubis At its lowermost aspect it joins the fibres of the aponeurosis of transversus abdominis to form the conjoint tendon. Transversus abdominis Innermost muscle Arises from the inner aspect of the costal cartilages of the lower 6 ribs , from the anterior 2/3 of the iliac crest and lateral 1/3 of the inguinal ligament Its fibres run horizontally around the abdominal wall ending in an aponeurosis. The upper part runs posterior to the rectus abdominis. Lower down the fibres run anteriorly only. The rectus abdominis lies medially; running from the pubic crest and symphysis to insert into the xiphoid process and 5th, 6th and 7th costal cartilages. The muscles lies in a aponeurosis as described above. Nerve supply: anterior primary rami of T7-12 Surgical notes During abdominal surgery it is usually necessary to divide either the muscles or their aponeuroses. During a midline laparotomy it is desirable to divide the aponeurosis. This will leave the rectus sheath intact above the arcuate line and the muscles intact below it. Straying off the midline will often lead to damage to the rectus muscles, particularly below the arcuate line where they may often be in close proximity to each other.

Answer 123

The common carotid artery is a lateral relation of the inferior parathyroid. Parathyroid glands- anatomy Four parathyroid glands Located posterior to the thyroid gland They lie within the pretracheal fascia Embryology The parathyroids develop from the extremities of the third and fourth pharyngeal pouches. The parathyroids derived from the fourth pharyngeal pouch are located more superiorly and are associated with the thyroid gland. Those derived from the third pharyngeal pouch lie more inferiorly and may become associated with the thymus. Blood supply The blood supply to the parathyroid glands is derived from the inferior and superior thyroid arteries[1]. There is a rich anastomosis between the two vessels. Venous drainage is into the thyroid veins. ``` Relations Laterally Common carotid Medially Recurrent laryngeal nerve, trachea Anterior Thyroid Posterior Pretracheal fascia ```

Answer 124

Anterolateral to the aorta Coeliac plexus The coeliac plexus is the largest of the autonomic plexuses. It is located on a level of the last thoracic and first lumbar vertebrae. It surrounds the coeliac axis and the SMA. It lies posterior to the stomach and the lesser sac. It lies anterior to the crura of the diaphragm and the aorta. The plexus and ganglia are joined by the greater and lesser splanchnic nerves on both sides and branches from both the vagus and phrenic nerves.

Answer 125

The fundus of the gallbladder lies at this level and is the most superficially located structure. Transpyloric plane Level of the body of L1 ``` Pylorus stomach Left kidney hilum (L1- left one!) Fundus of the gallbladder Neck of pancreas Duodenojejunal flexure Superior mesenteric artery Portal vein Left and right colic flexure Root of the transverse mesocolon 2nd part of the duodenum Upper part of conus medullaris Spleen ``` Can be identified by asking the supine patient to sit up without using their arms. The plane is located where the lateral border of the rectus muscle crosses the costal margin. Anatomical planes Subcostal plane Lowest margin of 10th costal cartilage Intercristal plane Level of body L4 (highest point of iliac crest) Intertubercular plane Level of body L5 ``` Common level landmarks Inferior mesenteric artery L3 Bifurcation of aorta into common iliac arteries L4 Formation of IVC L5 (union of common iliac veins) Diaphragm apertures Vena cava T8 Oesophagus T10 Aortic hiatus T12 ```

Answer 126

The circumflex humeral arteries lie at the surgical neck and is this scenario the posterior circumflex is likely to be injured. The thoracoacromial and transverse scapular arteries lie more superomedially. The posterior circumflex humeral artery is a branch of the axillary artery. Shoulder joint Shallow synovial ball and socket type of joint. It is an inherently unstable joint, but is capable to a wide range of movement. Stability is provided by muscles of the rotator cuff that pass from the scapula to insert in the greater tuberosity (all except sub scapularis-lesser tuberosity). Glenoid labrum Fibrocartilaginous rim attached to the free edge of the glenoid cavity Tendon of the long head of biceps arises from within the joint from the supraglenoid tubercle, and is fused at this point to the labrum. The long head of triceps attaches to the infraglenoid tubercle Fibrous capsule Attaches to the scapula external to the glenoid labrum and to the labrum itself (postero-superiorly) Attaches to the humerus at the level of the anatomical neck superiorly and the surgical neck inferiorly Anteriorly the capsule is in contact with the tendon of subscapularis, superiorly with the supraspinatus tendon, and posteriorly with the tendons of infraspinatus and teres minor. All these blend with the capsule towards their insertion. Two defects in the fibrous capsule; superiorly for the tendon of biceps. Anteriorly there is a defect beneath the subscapularis tendon. The inferior extension of the capsule is closely related to the axillary nerve at the surgical neck and this nerve is at risk in anteroinferior dislocations. It also means that proximally sited osteomyelitis may progress to septic arthritis. ``` Important anatomical relations Anteriorly Brachial plexus Axillary artery and vein Posterior Suprascapular nerve Suprascapular vessels Inferior Axillary nerve Circumflex humeral vessels ```

Answer 127

The carotid sheath is crossed anteriorly by the hypoglossal nerves and the ansa cervicalis. The vagus lies within it. The cervical sympathetic chain lies posteriorly between the sheath and the prevertebral fascia. Common carotid artery The right common carotid artery arises at the bifurcation of the brachiocephalic trunk, the left common carotid arises from the arch of the aorta. Both terminate at the level of the upper border of the thyroid cartilage (the lower border of the third cervical vertebra) by dividing into the internal and external carotid arteries. Left common carotid artery This vessel arises immediately to the left and slightly behind the origin of the brachiocephalic trunk. Its thoracic portion is 2.5- 3.5 cm in length and runs superolaterally to the sternoclavicular joint. In the thorax The vessel is in contact, from below upwards, with the trachea, left recurrent laryngeal nerve, left margin of the oesophagus. Anteriorly the left brachiocephalic vein runs across the artery, and the cardiac branches from the left vagus descend in front of it. These structures together with the thymus and the anterior margins of the left lung and pleura separate the artery from the manubrium. In the neck The artery runs superiorly deep to sternocleidomastoid and then enters the anterior triangle. At this point it lies within the carotid sheath with the vagus nerve and the internal jugular vein. Posteriorly the sympathetic trunk lies between the vessel and the prevertebral fascia. At the level of C7 the vertebral artery and thoracic duct lie behind it. The anterior tubercle of C6 transverse process is prominent and the artery can be compressed against this structure (it corresponds to the level of the cricoid). Anteriorly at C6 the omohyoid muscle passes superficial to the artery. Within the carotid sheath the jugular vein lies lateral to the artery. Right common carotid artery The right common carotid arises from the brachiocephalic artery. The right common carotid artery corresponds with the cervical portion of the left common carotid, except that there is no thoracic duct on the right. The oesophagus is less closely related to the right carotid than the left. Summary points about the carotid anatomy Path Passes behind the sternoclavicular joint (12% patients above this level) to the upper border of the thyroid cartilage, to divide into the external (ECA) and internal carotid arteries (ICA). Relations Level of 6th cervical vertebra crossed by omohyoid Then passes deep to the thyrohyoid, sternohyoid, sternomastoid muscles. Passes anterior to the carotid tubercle (transverse process 6th cervical vertebra)-NB compression here stops haemorrhage. The inferior thyroid artery passes posterior to the common carotid artery. Then : Left common carotid artery crosses the thoracic duct, Right common carotid artery crossed by recurrent laryngeal nerve

Answer 128

The coeliac axis branches off the aorta at T12. Coeliac axis The coeliac axis has three main branches. Left gastric Hepatic: branches-Right Gastric, Gastroduodenal, Superior Pancreaticoduodenal, Cystic (occasionally). Splenic: branches- Pancreatic, Short Gastric, Left Gastroepiploic Anteriorly Lesser omentum Right Right coeliac ganglion and caudate process of liver Left Left coeliac ganglion and gastric cardia Inferiorly Upper border of pancreas and renal vein

Answer 129

The external jugular vein runs obliquely in the superficial fascia of the posterior triangle. It drains into the subclavian vein. During surgical exploration of this area the external jugular vein may be injured and troublesome bleeding may result. The internal jugular vein and carotid arteries are located in the anterior triangle. The third, and not the second, part of the subclavian artery is also a content of the posterior triangle Posterior triangle of the neck Boundaries Apex Sternocleidomastoid and the Trapezius muscles at the Occipital bone Anterior Posterior border of the Sternocleidomastoid Posterior Anterior border of the Trapezius Base Middle third of the clavicle ``` Contents Nerves Accessory nerve Phrenic nerve Three trunks of the brachial plexus Branches of the cervical plexus: Supraclavicular nerve, transverse cervical nerve, great auricular nerve, lesser occipital nerve Vessels External jugular vein Subclavian artery Muscles Inferior belly of omohyoid Scalene Lymph nodes Supraclavicular Occipital ```

Answer 130

L3 Sensation over the knee is equivalent to the L3 dermatome. The four nerves involved include the infrapatellar branch of the saphenous nerve, the lateral cutaneous nerve of the thigh, anterior cutaneous nerve of the thigh (both lateral and medial branches). Spinal disorders ``` Dorsal column lesion Loss vibration and proprioception Tabes dorsalis, SACD Spinothalamic tract lesion Loss of pain, sensation and temperature Central cord lesion Flaccid paralysis of the upper limbs Osteomyelitis Normally progressive Staph aureus in IVDU, normally cervical region affected Fungal infections in immunocompromised Thoracic region affected in TB Infarction spinal cord Dorsal column signs (loss of proprioception and fine discrimination) Cord compression UMN signs Malignancy Haematoma Fracture Brown-sequard syndrome Hemisection of the spinal cord Ipsilateral paralysis Ipsilateral loss of proprioception and fine discrimination Contralateral loss of pain and temperature ```

Answer 131

C6 A C5 burst fracture usually injures the C6 spinal cord situated at the C5 vertebrae and also the C4 spinal roots that exit the spinal column between the C4 and C5 vertebra. Such an injury should cause a loss of sensations in C4 dermatome and weak deltoids. Due to oedema , the biceps (C5) may be initially weak but should recover. The wrist extensors (C6), however, should remain weak and sensation at and below C6 should be severely compromised. A neurosurgeon would conclude that there is a burst fracture at C5 from the x-rays, an initial sensory level at C4 (the first abnormal sensory dermatome) and the partial loss of deltoids and biceps would imply a motor level at C4 (the highest abnormal muscle level). Over time, as the patient recovers the C4 roots and the C5 spinal cord, both the sensory level and motor level should end up at C6. Such recovery is often attributed to 'root' recovery. Spinal disorders ``` Dorsal column lesion Loss vibration and proprioception Tabes dorsalis, SACD Spinothalamic tract lesion Loss of pain, sensation and temperature Central cord lesion Flaccid paralysis of the upper limbs Osteomyelitis Normally progressive Staph aureus in IVDU, normally cervical region affected Fungal infections in immunocompromised Thoracic region affected in TB Infarction spinal cord Dorsal column signs (loss of proprioception and fine discrimination) Cord compression UMN signs Malignancy Haematoma Fracture Brown-sequard syndrome Hemisection of the spinal cord Ipsilateral paralysis Ipsilateral loss of proprioception and fine discrimination Contralateral loss of pain and temperature ```

Answer 132

L5 Extensor hallucis longus is derived from L5 and loss of EHL function is a useful test to determine whether this level is involved. Spinal disorders ``` Dorsal column lesion Loss vibration and proprioception Tabes dorsalis, SACD Spinothalamic tract lesion Loss of pain, sensation and temperature Central cord lesion Flaccid paralysis of the upper limbs Osteomyelitis Normally progressive Staph aureus in IVDU, normally cervical region affected Fungal infections in immunocompromised Thoracic region affected in TB Infarction spinal cord Dorsal column signs (loss of proprioception and fine discrimination) Cord compression UMN signs Malignancy Haematoma Fracture Brown-sequard syndrome Hemisection of the spinal cord Ipsilateral paralysis Ipsilateral loss of proprioception and fine discrimination Contralateral loss of pain and temperature ``` Dermatomes C2 to C4 The C2 dermatome covers the occiput and the top part of the neck. C3 covers the lower part of the neck to the clavicle. C4 covers the area just below the clavicle. C5 to T1 Situated in the arms. C5 covers the lateral arm at and above the elbow. C6 covers the forearm and the radial (thumb) side of the hand. C7 is the middle finger, C8 is the medial aspect of the hand, and T1 covers the medial side of the forearm. T2 to T12 The thoracic covers the axillary and chest region. T3 to T12 covers the chest and back to the hip girdle. The nipples are situated in the middle of T4. T10 is situated at the umbilicus. T12 ends just above the hip girdle. L1 to L5 The cutaneous dermatome representing the hip girdle and groin area is innervated by L1 spinal cord. L2 and 3 cover the front part of the thighs. L4 and L5 cover medial and lateral aspects of the lower leg. S1 to S5 S1 covers the heel and the middle back of the leg. S2 covers the back of the thighs. S3 cover the medial side of the buttocks and S4-5 covers the perineal region. S5 is of course the lowest dermatome and represents the skin immediately at and adjacent to the anus.

Answer 133

The gluteus medius does not extend around to the sciatic nerve. Sciatic nerve The sciatic nerve is formed from the sacral plexus and is the largest nerve in the body. It is the continuation of the main part of the plexus arising from ventral rami of L4 to S3. These rami converge at the inferior border of piriformis to form the nerve itself. It passes through the inferior part of the greater sciatic foramen and emerges beneath piriformis. Medially, lie the inferior gluteal nerve and vessels and the pudendal nerve and vessels. It runs inferolaterally under the cover of gluteus maximus midway between the greater trochanter and ischial tuberosity. It receives its blood supply from the inferior gluteal artery. The nerve provides cutaneous sensation to the skin of the foot and the leg. It also innervates the posterior thigh muscles and the lower leg and foot muscles. The nerve splits into the tibial and common peroneal nerves approximately half way down the posterior thigh. The tibial nerve supplies the flexor muscles and the common peroneal nerve supplies the extensor muscles and the abductor muscles. ``` Summary points Origin Spinal nerves L4 - S3 Articular Branches Hip joint Muscular branches in upper leg Semitendinosus Semimembranosus Biceps femoris Part of adductor magnus Cutaneous sensation Posterior aspect of thigh (via cutaneous nerves) Gluteal region Entire lower leg (except the medial aspect) Terminates At the upper part of the popliteal fossa by dividing into the tibial and peroneal nerves ``` The nerve to the short head of the biceps femoris comes from the common peroneal part of the sciatic and the other muscular branches arise from the tibial portion. The tibial nerve goes on to innervate all muscles of the foot except the extensor digitorum brevis (which is innervated by the common peroneal nerve).

Answer 134

Mnemonic for radial nerve muscles: BEST B rachioradialis E xtensors S upinator T riceps Abductor digiti minimi is innervated by the ulnar nerve. Radial nerve Continuation of posterior cord of the brachial plexus (root values C5 to T1) Path In the axilla: lies posterior to the axillary artery on subscapularis, latissimus dorsi and teres major. Enters the arm between the brachial artery and the long head of triceps (medial to humerus). Spirals around the posterior surface of the humerus in the groove for the radial nerve. At the distal third of the lateral border of the humerus it then pierces the intermuscular septum and descends in front of the lateral epicondyle. At the lateral epicondyle it lies deeply between brachialis and brachioradialis where it then divides into a superficial and deep terminal branch. Deep branch crosses the supinator to become the posterior interosseous nerve. ``` Regions innervated Motor (main nerve) Triceps Anconeus Brachioradialis Extensor carpi radialis Motor (posterior interosseous branch) Supinator Extensor carpi ulnaris Extensor digitorum Extensor indicis Extensor digiti minimi Extensor pollicis longus and brevis Abductor pollicis longus Sensory The area of skin supplying the proximal phalanges on the dorsal aspect of the hand is supplied by the radial nerve (this does not apply to the little finger and part of the ring finger) ```

Answer 135

Femoral hernias exit the femoral canal below and lateral to the pubic tubercle. Femoral hernia occur mainly in women due to their difference in pelvic anatomy. They are at high risk of strangulation and therefore should be repaired. Femoral canal The femoral canal lies at the medial aspect of the femoral sheath. The femoral sheath is a fascial tunnel containing both the femoral artery laterally and femoral vein medially. The canal lies medial to the vein. ``` Borders of the femoral canal Laterally Femoral vein Medially Lacunar ligament Anteriorly Inguinal ligament Posteriorly Pectineal ligament ``` Contents Lymphatic vessels Cloquet's lymph node Physiological significance Allows the femoral vein to expand to allow for increased venous return to the lower limbs. Pathological significance As a potential space, it is the site of femoral hernias. The relatively tight neck places these at high risk of strangulation.

Answer 136

The inferior thyroid artery is usually derived from the thyrocervical trunk, a branch of the subclavian artery. Thoracic aorta Origin T4 Terminates T12 Relations Anteriorly (from top to bottom)-root of the left lung, the pericardium, the oesophagus, and the diaphragm Posteriorly-vertebral column, azygos vein Right- hemiazygos veins, thoracic duct Left- left pleura and lung Branches Lateral segmental branches: Posterior intercostal arteries Lateral visceral: Bronchial arteries supply bronchial walls and lung excluding the alveoli Midline branches: Oesophageal arteries

Answer 137

To treat hyperhidrosis the sympathetic ganglia at T2 and T3 should be divided. Dividing the other structures listed would either carry a risk of Horners syndrome or be ineffective. Sympathetic nervous system- anatomy The cell bodies of the pre-ganglionic efferent neurones lie in the lateral horn of the grey matter of the spinal cord in the thoraco-lumbar regions. The pre-ganglionic efferents leave the spinal cord at levels T1-L2. These pass to the sympathetic chain. Lateral branches of the sympathetic chain connect it to every spinal nerve. These post ganglionic nerves will pass to structures that receive sympathetic innervation at the periphery. Sympathetic chains These lie on the vertebral column and run from the base of the skull to the coccyx. Cervical region Lie anterior to the transverse processes of the cervical vertebrae and posterior to the carotid sheath. Thoracic region Lie anterior to the neck of the upper ribs and and lateral sides of the lower thoracic vertebrae.They are covered by the parietal pleura Lumbar region Enter by passing posterior to the medial arcuate ligament. Lie anteriorly to the vertebrae and medial to psoas major. Sympathetic ganglia Superior cervical ganglion lies anterior to C2 and C3. Middle cervical ganglion (if present) C6 Stellate ganglion- anterior to transverse process of C7, lies posterior to the subclavian artery, vertebral artery and cervical pleura. Thoracic ganglia are segmentally arranged. There are usually 4 lumbar ganglia. Clinical importance Interruption of the head and neck supply of the sympathetic nerves will result in an ipsilateral Horners syndrome. For treatment of hyperhidrosis the sympathetic denervation can be achieved by removing the second and third thoracic ganglia with their rami. Removal of T1 will cause a Horners syndrome and is therefore not performed. In patients with vascular disease of the lower limbs a lumbar sympathetomy may be performed, either radiologically or (more rarely now) surgically. The ganglia of L2 and below are disrupted. If L1 is removed then ejaculation may be compromised (and little additional benefit conferred as the preganglionic fibres do not arise below L2.

Answer 138

The gonadal vessels and ureter are important posterior relations that are at risk during a right hemicolectomy. Caecum ``` Location Proximal right colon below the ileocaecal valve Intraperitoneal Posterior relations Psoas Iliacus Femoral nerve Genitofemoral nerve Gonadal vessels Anterior relations Greater omentum Arterial supply Ileocolic artery Lymphatic drainage Mesenteric nodes accompany the venous drainage ``` The caecum is the most distensible part of the colon and in complete large bowel obstruction with a competent ileocaecal valve the most likely site of eventual perforation.

Answer 139

The thoracic duct lies posterior to the oesophagus and passes to the left at the level of the Angle of Louis. It enters the thorax at T12 together with the aorta. Thoracic duct Continuation of the cisterna chyli in the abdomen. Enters the thorax at T12. Lies posterior to the oesophagus for most of its intrathoracic course. Passes to the left at T5. Lymphatics draining the left side of the head and neck join the thoracic duct prior to its insertion into the left brachiocephalic vein. Lymphatics draining the right side of the head and neck drain via the subclavian and jugular trunks into the right lymphatic duct and thence into the mediastinal trunk and eventually the right brachiocephalic vein. Its location in the thorax makes it prone to injury during oesophageal surgery. Some surgeons administer cream to patients prior to oesophagectomy so that it is easier to identify the cut ends of the duct.

Answer 140

Flexor digitorum is supplied by the tibial nerve. Common peroneal nerve Derived from the dorsal divisions of the sacral plexus (L4, L5, S1 and S2). This nerve supplies the skin and fascia of the anterolateral surface of the leg and the dorsum of the foot. It also innervates the muscles of the anterior and peroneal compartments of the leg, extensor digitorum brevis as well as the knee, ankle and foot joints. It is laterally placed within the sciatic nerve. From the bifurcation of the sciatic nerve it passes inferolaterally in the lateral and proximal part of the popliteal fossa, under the cover of biceps femoris and its tendon. To reach the posterior aspect of the fibular head. It ends by dividing into the deep and superficial peroneal nerves at the point where it winds around the lateral surface of the neck of the fibula in the body of peroneus longus, approximately 2cm distal to the apex of the head of the fibula. It is palpable posterior to the head of the fibula. Branches In the thigh Nerve to the short head of biceps Articular branch (knee) In the popliteal fossa Lateral cutaneous nerve of the calf Neck of fibula Superficial and deep peroneal nerves

Answer 141

Pectineal ligament Femoral canal The femoral canal lies at the medial aspect of the femoral sheath. The femoral sheath is a fascial tunnel containing both the femoral artery laterally and femoral vein medially. The canal lies medial to the vein. ``` Borders of the femoral canal Laterally Femoral vein Medially Lacunar ligament Anteriorly Inguinal ligament Posteriorly Pectineal ligament ``` Contents Lymphatic vessels Cloquet's lymph node Physiological significance Allows the femoral vein to expand to allow for increased venous return to the lower limbs. Pathological significance As a potential space, it is the site of femoral hernias. The relatively tight neck places these at high risk of strangulation.

Answer 142

This is a description of Froment's sign, which tests for ulnar nerve palsy. It mainly tests for the function of adductor pollicis. This is supplied by the deep branch of the ulnar nerve. Remember the anterior interosseous branch (of the median nerve), which innervates the flexor pollicis longus (hence causing flexion of the thumb IP joint), branches off more proximally to the wrist. Ulnar nerve Origin C8, T1 ``` Supplies (no muscles in the upper arm) Flexor carpi ulnaris Flexor digitorum profundus Flexor digiti minimi Abductor digiti minimi Opponens digiti minimi Adductor pollicis Interossei muscle Third and fourth lumbricals Palmaris brevis ``` Path Posteromedial aspect of upper arm to flexor compartment of forearm, then along the ulnar. Passes beneath the flexor carpi ulnaris muscle, then superficially through the flexor retinaculum into the palm of the hand. Effects of injury Damage at the wrist Wasting and paralysis of intrinsic hand muscles (claw hand) Wasting and paralysis of hypothenar muscles Loss of sensation medial 1 and half fingers Damage at the elbow Radial deviation of the wrist Clawing less in 4th and 5th digits

Answer 143

It is connected with the lesser sac and the transverse colon. This plane is entered when performing a colonic resection. It is a common site of metastasis in many visceral malignancies. Omentum The omentum is divided into two parts which invest the stomach. Giving rise to the greater and lesser omentum. The greater omentum is attached to the inferolateral border of the stomach and houses the gastro-epiploic arteries. It is of variable size but is less well developed in children. This is important as the omentum confers protection against visceral perforation (e.g. Appendicitis). Inferiorly between the omentum and transverse colon is one potential entry point into the lesser sac. Several malignant processes may involve the omentum of which ovarian cancer is the most notable.

Answer 144

Lesser curvature of the stomach The left adrenal gland is slightly larger than the right. It is crescent in shape and its concavity is adapted to the medial border of the upper part of the left kidney. The upper area is covered by peritoneum of the omental bursa which separates it from the cardia of the stomach. The lower area is in contact with the pancreas and splenic artery and is not covered by peritoneum. On the anterior surface is a hilum from which the suprarenal vein emerges. The lateral aspect rests on the kidney. The medial is small and is on the left crus of the diaphragm. Adrenal gland anatomy Anatomy Location Superomedially to the upper pole of each kidney Relationships of the right adrenal Diaphragm-Posteriorly, Kidney-Inferiorly, Vena Cava-Medially, Hepato-renal pouch and bare area of the liver-Anteriorly Relationships of the left adrenal Crus of the diaphragm-Postero- medially, Pancreas and splenic vessels-Inferiorly, Lesser sac and stomach-Anteriorly Arterial supply Superior adrenal arteries- from inferior phrenic artery, Middle adrenal arteries - from aorta, Inferior adrenal arteries -from renal arteries Venous drainage of the right adrenal Via one central vein directly into the IVC Venous drainage of the left adrenal Via one central vein into the left renal vein

Answer 145

The short head of biceps femoris, which may occasionally be absent, is innervated by the common peroneal component of the sciatic nerve. The long head is innervated by the tibial division of the sciatic nerve. Biceps femoris The biceps femoris is one of the hamstring group of muscles located in the posterior upper thigh. It has two heads. Long head Origin Ischial tuberosity Insertion Fibular head Action Knee flexion, lateral rotation tibia, extension hip Innervation Tibial division of sciatic nerve (L5, S1, S2) Arterial supply Profunda femoris artery, inferior gluteal artery, and the superior muscular branches of popliteal artery Short head Origin Lateral lip of linea aspera, lateral supracondylar ridge of femur Insertion Fibular head Action Knee flexion, lateral rotation tibia Innervation Common peroneal division of sciatic nerve (L5, S1, S2) Arterial supply Profunda femoris artery, inferior gluteal artery, and the superior muscular branches of popliteal artery

Answer 146

Scalene anterior muscle The axillary artery is the continuation of the subclavian artery. It is surrounded by the cords of the brachial plexus (from which they are named). The axillary vein runs alongside the axillary artery throughout its length. Axilla Boundaries of the axilla Medially Chest wall and Serratus anterior Laterally Humeral head Floor Subscapularis Anterior aspect Lateral border of Pectoralis major Fascia Clavipectoral fascia Content: Long thoracic nerve (of Bell) Derived from C5-C7 and passes behind the brachial plexus to enter the axilla. It lies on the medial chest wall and supplies serratus anterior. Its location puts it at risk during axillary surgery and damage will lead to winging of the scapula. Thoracodorsal nerve and thoracodorsal trunk Innervate and vascularise latissimus dorsi. Axillary vein Lies at the apex of the axilla, it is the continuation of the basilic vein. Becomes the subclavian vein at the outer border of the first rib. Intercostobrachial nerves Traverse the axillary lymph nodes and are often divided during axillary surgery. They provide cutaneous sensation to the axillary skin. Lymph nodes The axilla is the main site of lymphatic drainage for the breast.

Answer 147

The phrenic nerve lies anteriorly at the root of the right lung. Lung anatomy The right lung is composed of 3 lobes divided by the oblique and transverse fissures. The left lung has two lobes divided by the oblique fissure.The apex of both lungs is approximately 4cm superior to the sterno-costal joint of the first rib. Immediately below this is a sulcus created by the subclavian artery. Peripheral contact points of the lung Base: diaphragm Costal surface: corresponds to the cavity of the chest Mediastinal surface: Contacts the mediastinal pleura. Has the cardiac impression. Above and behind this concavity is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These structures are invested by pleura, which, below the hilum and behind the pericardial impression, forms the pulmonary ligament Right lung Above the hilum is the azygos vein; Superior to this is the groove for the superior vena cava and right innominate vein; behind this, and nearer the apex, is a furrow for the innominate artery. Behind the hilum and the attachment of the pulmonary ligament is a vertical groove for the oesophagus; In front and to the right of the lower part of the oesophageal groove is a deep concavity for the extrapericardiac portion of the inferior vena cava. The root of the right lung lies behind the superior vena cava and the right atrium, and below the azygos vein. The right main bronchus is shorter, wider and more vertical than the left main bronchus and therefore the route taken by most foreign bodies. Left lung Above the hilum is the furrow produced by the aortic arch, and then superiorly the groove accommodating the left subclavian artery; Behind the hilum and pulmonary ligament is a vertical groove produced by the descending aorta, and in front of this, near the base of the lung, is the lower part of the oesophagus. The root of the left lung passes under the aortic arch and in front of the descending aorta. Inferior borders of both lungs 6th rib in mid clavicular line 8th rib in mid axillary line 10th rib posteriorly The pleura runs two ribs lower than the corresponding lung level.

Answer 148

Most appendixes lie in the retrocaecal position. If a retrocaecal appendix is difficult to remove then mobilisation of the right colon significantly improves access. Appendix Location: Base of caecum. Up to 10cm long. Mainly lymphoid tissue (Hence mesenteric adenitis may mimic appendicitis). Caecal taenia coli converge at base of appendix and form a longitudinal muscle cover over the appendix. This convergence should facilitate its identification at surgery if it is retrocaecal and difficult to find (which it can be when people start doing appendicectomies!) Arterial supply: Appendicular artery (branch of the ileocolic). It is intra peritoneal. McBurney's point 1/3 of the way along a line drawn from the Anterior Superior Iliac Spine to the Umbilicus 6 Positions: ``` Retrocaecal 74% Pelvic 21% Postileal Subcaecal Paracaecal Preileal ```

Answer 149

The gastroduodenal artery divides into the gastro-epiploic and pancreaticoduodenal arteries at the superior aspect of the pancreas. The pancreas is a retroperitoneal organ and lies posterior to the stomach. It may be accessed surgically by dividing the peritoneal reflection that connects the greater omentum to the transverse colon. The pancreatic head sits in the curvature of the duodenum. Its tail lies close to the hilum of the spleen, a site of potential injury during splenectomy. ``` Relations Posterior to the pancreas Pancreatic head Inferior vena cava Common bile duct Right and left renal veins Superior mesenteric vein and artery Pancreatic neck Superior mesenteric vein, portal vein Pancreatic body- Left renal vein Crus of diaphragm Psoas muscle Adrenal gland Kidney Aorta Pancreatic tail Left kidney ``` ``` Anterior to the pancreas Pancreatic head 1st part of the duodenum Pylorus Gastroduodenal artery SMA and SMV(uncinate process) Pancreatic body Stomach Duodenojejunal flexure Pancreatic tail Splenic hilum ``` Superior to the pancreas Coeliac trunk and its branches common hepatic artery and splenic artery Grooves of the head of the pancreas 2nd and 3rd part of the duodenum Arterial supply Head: pancreaticoduodenal artery Rest: splenic artery Venous drainage Head: superior mesenteric vein Body and tail: splenic vein Ampulla of Vater Merge of pancreatic duct and common bile duct Is an important landmark, halfway along the second part of the duodenum, that marks the anatomical transition from foregut to midgut (also the site of transition between regions supplied by coeliac trunk and SMA).

Answer 150

The cuboid is located at the lateral aspect of the foot between the calcaneus posteriorly and the 4th and 5th metatarsals distally. Arches of the foot The foot is conventionally considered to have two arches. The longitudinal arch is higher on the medial than on the lateral side. The posterior part of the calcaneum forms a posterior pillar to support the arch. The lateral part of this structure passes via the cuboid bone and the lateral two metatarsal bones. The medial part of this structure is more important. The head of the talus marks the summit of this arch, located between the sustentaculum tali and the navicular bone. The anterior pillar of the medial arch is composed of the navicular bone, the three cuneiforms and the medial three metatarsal bones. The transverse arch is situated on the anterior part of the tarsus and the posterior part of the metatarsus. The cuneiforms and metatarsal bases narrow inferiorly, which contributes to the shape of the arch. Intertarsal joints Sub talar joint Formed by the cylindrical facet on the lower surface of the body of the talus and the posterior facet on the upper surface of the calcaneus. The facet on the talus is concave anteroposteriorly, the other is convex. The synovial cavity of this joint does not communicate with any other joint. Talocalcaneonavicular joint The anterior part of the socket is formed by the concave articular surface of the navicular bone, posteriorly by the upper surface of the sustentaculum tali. The talus sits within this socket Calcaneocuboid joint Highest point in the lateral part of the longitudinal arch. The lower aspect of this joint is reinforced by the long plantar and plantar calcaneocuboid ligaments. Transverse tarsal joint The talocalcaneonavicular joint and the calcaneocuboid joint extend across the tarsus in an irregular transverse plane, between the talus and calcaneus behind and the navicular and cuboid bones in front. This plane is termed the transverse tarsal joint. Cuneonavicular joint Formed between the convex anterior surface of the navicular bone and the concave surface of the the posterior ends of the three cuneiforms. Intercuneiform joints Between the three cuneiform bones. Cuneocuboid joint Between the circular facets on the lateral cuneiform bone and the cuboid. This joint contributes to the tarsal part of the transverse arch. Nerves in the foot Lateral plantar nerve Passes anterolaterally towards the base of the 5th metatarsal between flexor digitorum brevis and flexor accessorius. On the medial aspect of the lateral plantar artery. At the base of the 5th metatarsal it splits into superficial and deep branches. Medial plantar nerve Passes forwards with the medial plantar artery under the cover of the flexor retinaculum to the interval between abductor hallucis and flexor digitorum brevis on the sole of the foot. Plantar arteries Arise under the cover of the flexor retinaculum, midway between the tip of the medial malleolus and the most prominent part of the medial side of the heel. Medial plantar artery. Passes forwards medial to medial plantar nerve in the space between abductor hallucis and flexor digitorum brevis.Ends by uniting with a branch of the 1st plantar metatarsal artery. Lateral plantar artery. Runs obliquely across the sole of the foot. It lies lateral to the lateral plantar nerve. At the base of the 5th metatarsal bone it arches medially across the foot on the metatarsals Dorsalis pedis artery This vessel is a direct continuation of the anterior tibial artery. It commences on the front of the ankle joint and runs to the proximal end of the first metatarsal space. Here is gives off the arcuate artery and continues forwards as the first dorsal metatarsal artery. It is accompanied by two veins throughout its length. It is crossed by the extensor hallucis brevis

Answer 151

The septum transversum is a thick ridge of mesodermal tissue in the developing embryo that separates the thoracic and abdominal cavities and forms the central tendon of the diaphragm. Embryology The diaphragm is formed between the 5th and 7th weeks of gestation through the progressive fusion of the septum transversum, pleuroperitoneal folds and via lateral muscular ingrowth. The muscular origins of the diaphragm are somites located in cervical segments 3 to 5, which accounts for the long path taken by the phrenic nerve. The components contribute to the following diaphragmatic segments: Septum transversum - Central tendon Pleuroperitoneal membranes - Parietal membranes surrounding viscera Cervical somites C5 to C7 - Muscular component of the diaphragm ``` Diaphragmatic hernia Type of hernia Features Morgagni Anteriorly located Minimal compromise on lung development Minimal signs on antenatal ultrasound Usually present later Usually good prognosis Bochdalek hernia Posteriorly located Larger defect Often diagnosed antenatally Associated with pulmonary hypoplasia Poor prognosis ``` The posterior hernias of Bochdalek are the most common type and if not diagnosed antenatally will typically present soon after birth with respiratory distress. The classical finding is that of a scaphoid abdomen on clinical examination because of herniation of the abdominal contents into the chest. Bochdalek hernias are associated with a number of chromosomal abnormalities such as Trisomy 21 and 18. Infants have considerable respiratory distress due to hypoplasia of the developing lung. Historically this was considered to be due to direct compression of the lung by herniated viscera. This view over simplifies the situation and the pulmonary hypoplasia occurs concomitantly with the hernial development, rather than as a direct result of it. The pulmonary hypoplasia is associated with pulmonary hypertension and abnormalities of pulmonary vasculature. The pulmonary hypertension renders infants at risk of right to left shunting (resulting in progressive and worsening hypoxia). Diagnostic work up of these infants includes chest x-rays/ abdominal ultrasound scans and cardiac echo. Surgery forms the mainstay of treatment and both thoracic and abdominal approaches may be utilised. Following reduction of the hernial contents a careful search needs to be made for a hernial sac as failure to recognise and correct this will result in a high recurrence rate. Smaller defects may be primarily closed, larger defects may require a patch to close the defect. Malrotation of the viscera is a recognised association and may require surgical correct at the same procedure (favoring an abdominal approach). The mortality rate is 50-75% and is related to the degree of lung compromise and age at presentation (considerably better in infants >24 hours old).

Answer 152

Stensens duct conveys secretions from the parotid gland and these enter the oral cavity at the level of the second molar tooth. Anatomy of the parotid gland Location Overlying the mandibular ramus; anterior and inferior to the ear. Salivary duct Crosses the masseter, pierces the buccinator and drains adjacent to the 2nd upper molar tooth (Stensen's duct). Structures passing through the gland Facial nerve (Mnemonic: The Zebra Buggered My Cat; Temporal Zygomatic, Buccal, Mandibular, Cervical) External carotid artery Retromandibular vein Auriculotemporal nerve Relations Anterior: masseter, medial pterygoid, superficial temporal and maxillary artery, facial nerve, stylomandibular ligament Posterior: posterior belly digastric muscle, sternocleidomastoid, stylohyoid, internal carotid artery, mastoid process, styloid process Arterial supply Branches of external carotid artery Venous drainage Retromandibular vein Lymphatic drainage Deep cervical nodes Nerve innervation Parasympathetic-Secretomotor Sympathetic-Superior cervical ganglion Sensory- Greater auricular nerve Parasympathetic stimulation produces a water rich, serous saliva. Sympathetic stimulation leads to the production of a low volume, enzyme-rich saliva.

Answer 153

The posterior belly of digastric is innervated by the facial nerve and the anterior belly by the mylohoid nerve. Anterior triangle of the neck Boundaries Anterior border of the Sternocleidomastoid Lower border of mandible Anterior midline Sub triangles (divided by Digastric above and Omohyoid) Muscular triangle: Neck strap muscles Carotid triangle: Carotid sheath Submandibular Triangle (digastric) ``` Contents of the anterior triangle Digastric triangle Submandibular gland Submandibular nodes Facial vessels Hypoglossal nerve Muscular triangle Strap muscles External jugular vein Carotid triangle Carotid sheath (Common carotid, vagus and internal jugular vein) Ansa cervicalis ``` Nerve supply to digastric muscle Anterior: Mylohyoid nerve Posterior: Facial nerve

Answer 154

Pisiform This small bone has a single articular facet. It projects from the triquetral bone at the ulnar aspect of the wrist where most regard it as a sesamoid bone lying within the tendon of flexor carpi ulnaris. Carpal bones The wrist is comprised of 8 carpal bones, these are arranged in two rows of 4. It is convex from side to side posteriorly and concave anteriorly. No tendons attach to: Scaphoid, lunate, triquetrum (stabilised by ligaments)

Answer 155

The lunate lies medially in the anatomical plane. Fractures of the scaphoid that are associated with high velocity injuries may cause associated lunate dislocation. The scaphoid has a concave articular surface for the head of the capitate and at the edge of this is a crescentic surface for the corresponding area on the lunate. Proximally, it has a wide convex articular surface with the radius. It has a distally sited tubercle that can be palpated. The remaining articular surface is to the lateral side of the tubercle. It faces laterally and is associated with the trapezium and trapezoid bones. The narrow strip between the radial and trapezial surfaces and the tubercle gives rise to the radial collateral carpal ligament. The tubercle receives part of the flexor retinaculum. This area is the only part of the scaphoid that is available for the entry of blood vessels. It is commonly fractured and avascular necrosis may result.

Answer 156

The vessel will be the gastroduodenal artery, this arises from the common hepatic artery. Gastroduodenal artery Supplies Pylorus, proximal part of the duodenum, and indirectly to the pancreatic head (via the anterior and posterior superior pancreaticoduodenal arteries) Path The gastroduodenal artery most commonly arises from the common hepatic artery of the coeliac trunk. It terminates by bifurcating into the right gastroepiploic artery and the superior pancreaticoduodenal artery

Answer 157

The triceps will not be affected so elbow extension will be preserved. Loss of wrist extension will be the most obvious effect. Radial nerve Continuation of posterior cord of the brachial plexus (root values C5 to T1) Path In the axilla: lies posterior to the axillary artery on subscapularis, latissimus dorsi and teres major. Enters the arm between the brachial artery and the long head of triceps (medial to humerus). Spirals around the posterior surface of the humerus in the groove for the radial nerve. At the distal third of the lateral border of the humerus it then pierces the intermuscular septum and descends in front of the lateral epicondyle. At the lateral epicondyle it lies deeply between brachialis and brachioradialis where it then divides into a superficial and deep terminal branch. Deep branch crosses the supinator to become the posterior interosseous nerve.

Answer 158

This is a typical description of Perthes disease. Management involves keeping the femoral head in the acetabulum by braces, casts or surgery. Perthes disease Idiopathic avascular necrosis of the femoral epiphysis of the femoral head Impaired blood supply to femoral head, causing bone infarction. New vessels develop and ossification occurs. The bone either heals or a subchondral fracture occurs. ``` Clinical features Males 4x's greater than females Age between 2-12 years (the younger the age of onset, the better the prognosis) Limp Hip pain Bilateral in 20% ``` Diagnosis Plain x-ray, Technetium bone scan or magnetic resonance imaging if normal x-ray and symptoms persist. Catterall staging Stage Features Stage 1 Clinical and histological features only Stage 2 Sclerosis with or without cystic changes and preservation of the articular surface Stage 3 Loss of structural integrity of the femoral head Stage 4 Loss of acetabular integrity Management To keep the femoral head within the acetabulum: cast, braces If less than 6 years: observation Older: surgical management with moderate results Operate on severe deformities Prognosis Most cases will resolve with conservative management. Early diagnosis improves outcomes.

Answer 159

False: All cases should be treated with an Ilizarov frame initially unless there is minor deformity. In most cases of Club Foot conservative measures should be tried first. The Ponsetti method is a popular approach. Severe cases may benefit from Ilizarov frame re-aligment. ``` Congenital talipes equinovarus. Features: Equinus of the hindfoot. Adduction and varus of the midfoot. High arch. ``` Most cases in developing countries. Incidence in UK is 1 per 1000 live births. It is more common in males and is bilateral in 50% cases. There is a strong familial link(1). It may also be associated with other developmental disorders such as Down's syndrome. ``` Key anatomical deformities (2): Adducted and inverted calcaneus Wedge shaped distal calcaneal articular surface Severe Tibio-talar plantar flexion. Medial Talar neck inclination Displacement of the navicular bone (medially) Wedge shaped head of talus Displacement of the cuboid (medially) ``` Management Conservative first, the Ponseti method is best described and gives comparable results to surgery. It consists of serial casting to mold the foot into correct shape. Following casting around 90% will require a Achilles tenotomy. This is then followed by a phase of walking braces to maintain the correction. Surgical correction is reserved for those cases that fail to respond to conservative measures. The procedures involve multiple tenotomies and lengthening procedures. In patients who fail to respond surgically an Ilizarov frame reconstruction may be attempted and gives good results.

Answer 160

Rectus sheath doesn't contain ext. iliac artery The rectus sheath also contains: superior epigastric vein inferior epigastric artery The 2 main muscles of the abdominal wall are the rectus abdominis (anterior) and the quadratus lumborum (posterior). The remaining abdominal wall consists of 3 muscular layers. Each muscle passes from the lateral aspect of the quadratus lumborum posteriorly to the lateral margin of the rectus sheath anteriorly. Each layer is muscular posterolaterally and aponeurotic anteriorly. Muscles of abdominal wall External oblique Lies most superficially Originates from 5th to 12th ribs Inserts into the anterior half of the outer aspect of the iliac crest, linea alba and pubic tubercle More medially and superiorly to the arcuate line, the aponeurotic layer overlaps the rectus abdominis muscle The lower border forms the inguinal ligament The triangular expansion of the medial end of the inguinal ligament is the lacunar ligament. Internal oblique Arises from the thoracolumbar fascia, the anterior 2/3 of the iliac crest and the lateral 2/3 of the inguinal ligament The muscle sweeps upwards to insert into the cartilages of the lower 3 ribs The lower fibres form an aponeurosis that runs from the tenth costal cartilage to the body of the pubis At its lowermost aspect it joins the fibres of the aponeurosis of transversus abdominis to form the conjoint tendon. Transversus abdominis Innermost muscle Arises from the inner aspect of the costal cartilages of the lower 6 ribs , from the anterior 2/3 of the iliac crest and lateral 1/3 of the inguinal ligament Its fibres run horizontally around the abdominal wall ending in an aponeurosis. The upper part runs posterior to the rectus abdominis. Lower down the fibres run anteriorly only. The rectus abdominis lies medially; running from the pubic crest and symphysis to insert into the xiphoid process and 5th, 6th and 7th costal cartilages. The muscles lies in a aponeurosis as described above. Nerve supply: anterior primary rami of T7-12 Surgical notes During abdominal surgery it is usually necessary to divide either the muscles or their aponeuroses. During a midline laparotomy it is desirable to divide the aponeurosis. This will leave the rectus sheath intact above the arcuate line and the muscles intact below it. Straying off the midline will often lead to damage to the rectus muscles, particularly below the arcuate line where they may often be in close proximity to each other.

Answer 161

The superior mesenteric vein drains into the portal vein. The right and left hepatic veins drain into it directly, this can account for major bleeding in more extensive liver shearing type injuries. Inferior vena cava Origin L5 Path Left and right common iliac veins merge to form the IVC. Passes right of midline Paired segmental lumbar veins drain into the IVC throughout its length The right gonadal vein empties directly into the cava and the left gonadal vein generally empties into the left renal vein. The next major veins are the renal veins and the hepatic veins Pierces the central tendon of diaphragm at T8 Right atrium Relations Anteriorly Small bowel, first and third part of duodenum, head of pancreas, liver and bile duct, right common iliac artery, right gonadal artery Posteriorly Right renal artery, right psoas, right sympathetic chain, coeliac ganglion ``` Levels Level Vein T8 Hepatic vein, inferior phrenic vein, pierces diaphragm L1 Suprarenal veins, renal vein L2 Gonadal vein L1-5 Lumbar veins L5 Common iliac vein, formation of IVC ```

Answer 162

The layers that will be encountered are (in order): 1. Skin 2. Dartos fascia and muscle 3. External spermatic fascia 4. Cremasteric muscle and fascia 5. Internal spermatic fascia 6. Parietal layer of the tunica vaginalis The layers of the spermatic cord and scrotum are a popular topic in the MRCS exam. A mnemonic which may help: Some Damned Examiner Called It The Testes (skin dartos external fascia cremaster internal fascia tunica Testes) Spermatic cord Formed by the vas deferens and is covered by the following structures: Layer Origin Internal spermatic fascia Transversalis fascia Cremasteric fascia From the fascial coverings of internal oblique External spermatic fascia External oblique aponeurosis Contents of the cord Vas deferens Transmits sperm and accessory gland secretions Testicular artery Branch of abdominal aorta supplies testis and epididymis Artery of vas deferens Arises from inferior vesical artery Cremasteric artery Arises from inferior epigastric artery Pampiniform plexus Venous plexus, drains into right or left testicular vein Sympathetic nerve fibres Lie on arteries, the parasympathetic fibres lie on the vas Genital branch of the genitofemoral nerve Supplies cremaster Lymphatic vessels Drain to lumbar and para-aortic nodes Scrotum Composed of skin and closely attached dartos fascia. Arterial supply from the anterior and posterior scrotal arteries Lymphatic drainage to the inguinal lymph nodes Parietal layer of the tunica vaginalis is the innermost layer Testes The testes are surrounded by the tunica vaginalis (closed peritoneal sac). The parietal layer of the tunica vaginalis adjacent to the internal spermatic fascia. The testicular arteries arise from the aorta immediately inferiorly to the renal arteries. The pampiniform plexus drains into the testicular veins, the left drains into the left renal vein and the right into the inferior vena cava. Lymphatic drainage is to the para-aortic nodes.

Answer 163

Vertigo and dysarthria suggest a posterior circulation event. In the scenario of a patient complaining of posterior symptoms and a sudden deterioration in consciousness, the main differential diagnosis is of a basilar artery occlusion. Primary intracerebral haemorrhage (PICH, c. 10%) Presents with headache, vomiting, loss of consciousness Total anterior circulation infarcts (TACI, c. 15%) Involves middle and anterior cerebral arteries Hemiparesis/hemisensory loss Homonymous hemianopia Higher cognitive dysfunction e.g. Dysphasia Partial anterior circulation infarcts (PACI, c. 25%) Involves smaller arteries of anterior circulation e.g. upper or lower division of middle cerebral artery Higher cognitive dysfunction or two of the three TACI features Lacunar infarcts (LACI, c. 25%) Involves perforating arteries around the internal capsule, thalamus and basal ganglia Present with either isolated hemiparesis, hemisensory loss or hemiparesis with limb ataxia Posterior circulation infarcts (POCI, c. 25%) Vertebrobasilar arteries Presents with features of brainstem damage Ataxia, disorders of gaze and vision, cranial nerve lesions Lateral medullary syndrome (posterior inferior cerebellar artery) Wallenberg's syndrome Ipsilateral: ataxia, nystagmus, dysphagia, facial numbness, cranial nerve palsy Contralateral: limb sensory loss Weber's syndrome Ipsilateral III palsy Contralateral weakness -------------------------------------- Anterior cerebral artery Contralateral hemiparesis and sensory loss, lower extremity > upper Disconnection syndrome ``` Middle cerebral artery Contralateral hemiparesis and sensory loss, upper extremity > lower Contralateral hemianopia Aphasia (Wernicke's) Gaze abnormalities ``` Posterior cerebral artery Contralateral hemianopia with macular sparing Disconnection syndrome Lacunar Present with either isolated hemiparesis, hemisensory loss or hemiparesis with limb ataxia ``` Lateral medulla (posterior inferior cerebellar artery) Ipsilateral: ataxia, nystagmus, dysphagia, facial numbness, cranial nerve palsy e.g. ``` Horner's Contralateral: limb sensory loss Pontine VI nerve: horizontal gaze palsy VII nerve Contralateral hemiparesis

Answer 164

This man is likely to have muscle death secondary to compartment syndrome. This will result in muscle breakdown and release of myoglobin. This may accumulate in the kidney and result in renal failure. Compartment syndrome This is a particular complication that may occur following fractures (or following ischaemia re-perfusion injury in vascular patients). It is characterised by raised pressure within a closed anatomical space. The raised pressure within the compartment will eventually compromise tissue perfusion resulting in necrosis. The two main fractures carrying this complication include supracondylar fractures and tibial shaft injuries. Symptoms and signs Pain, especially on movement (even passive) Parasthesiae Pallor may be present Arterial pulsation may still be felt as the necrosis occurs as a result of microvascular compromise Paralysis of the muscle group may occur Diagnosis Is made by measurement of intracompartmental pressure measurements. Pressures in excess of 20mmHg are abnormal and >40mmHg is diagnostic. Treatment This is essentially prompt and extensive fasciotomies In the lower limb the deep muscles may be inadequately decompressed by the inexperienced operator when smaller incisions are performed Myoglobinuria may occur following fasciotomy and result in renal failure and for this reason these patients require aggressive IV fluids Where muscle groups are frankly necrotic at fasciotomy they should be debrided and amputation may have to be considered Death of muscle groups may occur within 4-6 hours

Answer 165

The sartorius forms the lateral wall of the femoral triangle ``` Femoral triangle anatomy Boundaries Superiorly Inguinal ligament Laterally Sartorius Medially Adductor longus Floor Iliopsoas, adductor longus and pectineus Roof Fascia lata and Superficial fascia Superficial inguinal lymph nodes (palpable below the inguinal ligament) Long saphenous vein ``` Contents Femoral vein (medial to lateral) Femoral artery-pulse palpated at the mid inguinal point Femoral nerve Deep and superficial inguinal lymph nodes Lateral cutaneous nerve Great saphenous vein Femoral branch of the genitofemoral nerve

Answer 166

Median Nerve The flexor digiti minimi brevis originates from the Hamate, on its under- surface lie the ulnar contribution to the superficial palmar arterial arch and digital nerves derived from the ulnar nerve. The median nerve overlies the flexor tendons. ``` Anatomy of the hand Bones 8 Carpal bones 5 Metacarpals 14 phalanges Intrinsic Muscles 7 Interossei - Supplied by ulnar nerve 3 palmar-adduct fingers 4 dorsal- abduct fingers Intrinsic muscles Lumbricals Flex MCPJ and extend the IPJ. Origin deep flexor tendon and insertion dorsal extensor hood mechanism. Innervation: 1st and 2nd- median nerve, 3rd and 4th- deep branch of the ulnar nerve. Thenar eminence Abductor pollicis brevis Opponens pollicis Flexor pollicis brevis Hypothenar eminence Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi ``` Fascia and compartments of the palm The fascia of the palm is continuous with the antebrachial fascia and the fascia of the dorsum of the hand. The palmar fascia is thin over the thenar and hypothenar eminences. In contrast, the central palmar fascia is relatively thick. The palmar aponeurosis covers the soft tissues and overlies the flexor tendons. The apex of the palmar aponeurosis is continuous with the flexor retinaculum and the palmaris longus tendon. Distally, it forms four longitudinal digital bands that attach to the bases of the proximal phalanges, blending with the fibrous digital sheaths. A medial fibrous septum extends deeply from the medial border of the palmar aponeurosis to the 5th metacarpal. Lying medial to this are the hypothenar muscles. In a similar fashion, a lateral fibrous septum extends deeply from the lateral border of the palmar aponeurosis to the 3rd metacarpal. The thenar compartment lies lateral to this area. Lying between the thenar and hypothenar compartments is the central compartment. It contains the flexor tendons and their sheaths, the lumbricals, the superficial palmar arterial arch and the digital vessels and nerves. The deepest muscular plane is the adductor compartment, which contains adductor pollicis. Short muscles of the hand These comprise the lumbricals and interossei. The four slender lumbrical muscles flex the fingers at the metacarpophalangeal joints and extend the interphalangeal joint. The four dorsal interossei are located between the metacarpals and the four palmar interossei lie on the palmar surface of the metacarpals in the interosseous compartment of the hand. Long flexor tendons and sheaths in the hand The tendons of FDS and FDP enter the common flexor sheath deep to the flexor retinaculum. The tendons enter the central compartment of the hand and fan out to their respective digital synovial sheaths. Near the base of the proximal phalanx, the tendon of FDS splits to permit the passage of FDP. The FDP tendons are attached to the margins of the anterior aspect of the base of the distal phalanx. The fibrous digital sheaths contain the flexor tendons and their synovial sheaths. These extend from the heads of the metacarpals to the base of the distal phalanges.

Answer 167

The transversalis fascia forms the superolateral edge of the deep inguinal ring. The epigastric vessels form its inferomedial wall. Inguinal canal Location Above the inguinal ligament The inguinal canal is 4cm long The superficial ring is located anterior to the pubic tubercle The deep ring is located approximately 1.5-2cm above the half way point between the anterior superior iliac spine and the pubic tubercle ``` Boundaries of the inguinal canal Floor External oblique aponeurosis Inguinal ligament Lacunar ligament Roof Internal oblique Transversus abdominis Anterior wall External oblique aponeurosis Posterior wall Transversalis fascia Conjoint tendon Laterally Internal ring Transversalis fascia Fibres of internal oblique Medially External ring Conjoint tendon ``` Contents Males Spermatic cord and ilioinguinal nerve As it passes through the canal the spermatic cord has 3 coverings: External spermatic fascia from external oblique aponeurosis Cremasteric fascia Internal spermatic fascia Females Round ligament of uterus and ilioinguinal nerve

Answer 168

The 5th tendon sheath extends from the little finger to the proximal aspect of the carpal tunnel. This carries a significant risk of allowing infections to migrate proximally. ``` Hand Anatomy of the hand Bones 8 Carpal bones 5 Metacarpals 14 phalanges Intrinsic Muscles 7 Interossei - Supplied by ulnar nerve 3 palmar-adduct fingers 4 dorsal- abduct fingers Intrinsic muscles Lumbricals Flex MCPJ and extend the IPJ. Origin deep flexor tendon and insertion dorsal extensor hood mechanism. Innervation: 1st and 2nd- median nerve, 3rd and 4th- deep branch of the ulnar nerve. Thenar eminence Abductor pollicis brevis Opponens pollicis Flexor pollicis brevis Hypothenar eminence Opponens digiti minimi Flexor digiti minimi brevis Abductor digiti minimi ``` Fascia and compartments of the palm The fascia of the palm is continuous with the antebrachial fascia and the fascia of the dorsum of the hand. The palmar fascia is thin over the thenar and hypothenar eminences. In contrast, the central palmar fascia is relatively thick. The palmar aponeurosis covers the soft tissues and overlies the flexor tendons. The apex of the palmar aponeurosis is continuous with the flexor retinaculum and the palmaris longus tendon. Distally, it forms four longitudinal digital bands that attach to the bases of the proximal phalanges, blending with the fibrous digital sheaths. A medial fibrous septum extends deeply from the medial border of the palmar aponeurosis to the 5th metacarpal. Lying medial to this are the hypothenar muscles. In a similar fashion, a lateral fibrous septum extends deeply from the lateral border of the palmar aponeurosis to the 3rd metacarpal. The thenar compartment lies lateral to this area. Lying between the thenar and hypothenar compartments is the central compartment. It contains the flexor tendons and their sheaths, the lumbricals, the superficial palmar arterial arch and the digital vessels and nerves. The deepest muscular plane is the adductor compartment, which contains adductor pollicis. Short muscles of the hand These comprise the lumbricals and interossei. The four slender lumbrical muscles flex the fingers at the metacarpophalangeal joints and extend the interphalangeal joint. The four dorsal interossei are located between the metacarpals and the four palmar interossei lie on the palmar surface of the metacarpals in the interosseous compartment of the hand. Long flexor tendons and sheaths in the hand The tendons of FDS and FDP enter the common flexor sheath deep to the flexor retinaculum. The tendons enter the central compartment of the hand and fan out to their respective digital synovial sheaths. Near the base of the proximal phalanx, the tendon of FDS splits to permit the passage of FDP. The FDP tendons are attached to the margins of the anterior aspect of the base of the distal phalanx. The fibrous digital sheaths contain the flexor tendons and their synovial sheaths. These extend from the heads of the metacarpals to the base of the distal phalanges.

Answer 169

Opponens Pollicis Ulnar nerve Origin C8, T1 ``` Supplies (no muscles in the upper arm) Flexor carpi ulnaris Flexor digitorum profundus Flexor digiti minimi Abductor digiti minimi Opponens digiti minimi Adductor pollicis Interossei muscle Third and fourth lumbricals Palmaris brevis ``` Path Posteromedial aspect of upper arm to flexor compartment of forearm, then along the ulnar. Passes beneath the flexor carpi ulnaris muscle, then superficially through the flexor retinaculum into the palm of the hand. Branch Supplies Muscular branch Flexor carpi ulnaris Medial half of the flexor digitorum profundus Palmar cutaneous branch (Arises near the middle of the forearm) Skin on the medial part of the palm Dorsal cutaneous branch Dorsal surface of the medial part of the hand Superficial branch Cutaneous fibres to the anterior surfaces of the medial one and one-half digits Deep branch Hypothenar muscles All the interosseous muscles Third and fourth lumbricals Adductor pollicis Medial head of the flexor pollicis brevis Effects of injury Damage at the wrist Wasting and paralysis of intrinsic hand muscles (claw hand) Wasting and paralysis of hypothenar muscles Loss of sensation medial 1 and half fingers Damage at the elbow Radial deviation of the wrist Clawing less in 4th and 5th digits

Answer 170

Ilioinguinal nerve entrapment may be a cause of neuropathic pain following inguinal hernia surgery. The ilioinguinal nerve passes through the superfical inguinal ring and is routinely encountered when exploring the inguinal canal during hernia surgery. The iliohypogastric nerve pierces the aponeurosis of the external oblique muscle superior to the superficial inguinal ring Ilioinguinal nerve Arises from the first lumbar ventral ramus with the iliohypogastric nerve. It passes inferolaterally through the substance of psoas major and over the anterior surface of quadratus lumborum. It pierces the internal oblique muscle and passes deep to the aponeurosis of the external oblique muscle. It enters the inguinal canal and then passes through the superficial inguinal ring to reach the skin. Branches To supply those muscles of the abdominal wall through which it passes. Skin and fascia over the pubic symphysis, superomedial part of the femoral triangle, surface of the scrotum, root and dorsum of penis or labum majus in females.

Answer 171

Intravenous nalaxone is needed to treat the patient who has had an overdose of opiate. Naloxone has the quickest onset of action, however it is important to be aware of its short acting duration and the need for further administration. There is also the risk of rebound pain once naloxone is given. Opioid misuse Opioids are substances which bind to opioid receptors. This includes both naturally occurring opiates such as morphine and synthetic opioids such as buprenorphine and methadone. ``` Features of opioid misuse Rhinorrhoea Needle track marks Pinpoint pupils Drowsiness ``` Complications of intravenous opioid misuse Viral infection secondary to sharing needles: HIV, hepatitis B & C Bacterial infection secondary to injection: infective endocarditis, septic arthritis, septicaemia, necrotising fasciitis, groin abscess Pseudoaneurysm Venous thromboembolism Osteomyelitis Overdose may lead to respiratory depression and death Emergency management of opioid overdose IV or IM naloxone: has a rapid onset and relatively short duration of action

Answer 172

Periosteal preservation helps fractures to heal. Bone fracture - Bleeding vessels in the bone and periosteum - Clot and haematoma formation - The clot organises over a week (improved structure and collagen) - The periosteum contains osteoblasts which produce new bone - Mesenchymal cells produce cartilage (fibrocartilage and hyaline cartilage) in the soft tissue around the fracture - Connective tissue + hyaline cartilage = callus - As the new bone approaches the new cartilage, endochondral ossification occurs to bridge the gap - Trabecular bone forms - Trabecular bone is resorbed by osteoclasts and replaced with compact bone Factors affecting fracture healing Age Malnutrition Bone disorders: osteoporosis Systemic disorders: diabetes, Marfan's syndrome and Ehlers-Danlos syndrome cause abnormal musculoskeletal healing. Drugs: steroids, non steroidal anti inflammatory agents. Type of bone: Cancellous (spongy) bone fractures are usually more stable, involve greater surface areas, and have a better blood supply than cortical (compact) bone fractures. Degree of Trauma: The more extensive the injury to bone and surrounding soft tissue, the poorer the outcome. Vascular Injury: Especially the femoral head, talus, and scaphoid bones. Degree of Immobilization Intra-articular Fractures: These fractures communicate with synovial fluid, which contains collagenases that retard bone healing. Separation of Bone Ends: Normal apposition of fracture fragments is needed for union to occur. Inadequate reduction, excessive traction, or interposition of soft tissue will prevent healing. Infection

Answer 173

ECG changes for thrombolysis or percutaneous intervention: ST elevation of > 2mm (2 small squares) in 2 or more consecutive anterior leads (V1-V6) OR ST elevation of greater than 1mm (1 small square) in greater than 2 consecutive inferior leads (II, III, avF, avL) OR New Left bundle branch block ST elevation of 1mm in leads II, III and aVF reflects significant cardiac ischaemia due to the right coronary artery occlusion. The medical registrar should be contacted to urgently assess the patient. Note right coronary artery occlusions puts the patient at risk of cardiac arrhythmias (due to blood supply to the sino atrial node). Thrombolysis or percutaneous intervention in myocardial infarction Thrombolytic drugs activate plasminogen to form plasmin. This in turn degrades fibrin and help breaks up thrombi. They in primarily used in patients who present with a ST elevation myocardial infarction. Other indications include acute ischaemic stroke and pulmonary embolism, although strict inclusion criteria apply. Examples alteplase tenecteplase streptokinase ``` Contraindications to thrombolysis active internal bleeding recent haemorrhage, trauma or surgery (including dental extraction) coagulation and bleeding disorders intracranial neoplasm stroke < 3 months aortic dissection recent head injury pregnancy severe hypertension ``` Side-effects haemorrhage hypotension - more common with streptokinase allergic reactions may occur with streptokinase

Answer 174

The axillary artery is a branch of the subclavian artery and although developmental anomalies may occur they are rare. The catheter may also enter the right carotid. There is no brachiocephalic artery on the left side. Brachiocephalic artery The brachiocephalic artery is the largest branch of the aortic arch. From its aortic origin it ascends superiorly, it initially lies anterior to the trachea and then on its right hand side. It branches into the common carotid and right subclavian arteries at the level of the sternoclavicular joint. Path Origin- apex of the midline of the aortic arch Passes superiorly and posteriorly to the right Divides into the right subclavian and right common carotid artery ``` Relations Anterior Sternohyoid Sternothyroid Thymic remnants Left brachiocephalic vein Right inferior thyroid veins Posterior Trachea Right pleura Right lateral Right brachiocephalic vein Superior part of SVC Left lateral Thymic remnants Origin of left common carotid Inferior thyroid veins Trachea (higher level) ``` Branches Normally none but may have the thyroidea ima artery

Answer 175

The radial nerve runs in its groove on between the two heads. The ulnar nerve lies anterior to the medial head. The axillary nerve passes through the quadrangular space. This lies superior to lateral head of the triceps muscle and thus the lateral border of the quadrangular space is the humerus. Therefore the correct answer is the radial nerve. Triceps Origin Long head- infraglenoid tubercle of the scapula. Lateral head- dorsal surface of the humerus, lateral and proximal to the groove of the radial nerve Medial head- posterior surface of the humerus on the inferomedial side of the radial groove and both of the intermuscular septae Insertion Olecranon process of the ulna. Here the olecranon bursa is between the triceps tendon and olecranon. Some fibres insert to the deep fascia of the forearm, posterior capsule of the elbow (preventing the capsule from being trapped between olecranon and olecranon fossa during extension) Innervation Radial nerve Blood supply Profunda brachii artery Action Elbow extension. The long head can adduct the humerus and and extend it from a flexed position Relations The radial nerve and profunda brachii vessels lie between the lateral and medial heads

Answer 176

The shoulder joint is a shallow joint, hence its great mobility. However, this comes at the expense of stability. The fibrous capsule attaches to the anatomical neck superiorly and the surgical neck inferiorly Shoulder joint Shallow synovial ball and socket type of joint. It is an inherently unstable joint, but is capable to a wide range of movement. Stability is provided by muscles of the rotator cuff that pass from the scapula to insert in the greater tuberosity (all except sub scapularis-lesser tuberosity). Glenoid labrum Fibrocartilaginous rim attached to the free edge of the glenoid cavity Tendon of the long head of biceps arises from within the joint from the supraglenoid tubercle, and is fused at this point to the labrum. The long head of triceps attaches to the infraglenoid tubercle Fibrous capsule Attaches to the scapula external to the glenoid labrum and to the labrum itself (postero-superiorly) Attaches to the humerus at the level of the anatomical neck superiorly and the surgical neck inferiorly Anteriorly the capsule is in contact with the tendon of subscapularis, superiorly with the supraspinatus tendon, and posteriorly with the tendons of infraspinatus and teres minor. All these blend with the capsule towards their insertion. Two defects in the fibrous capsule; superiorly for the tendon of biceps. Anteriorly there is a defect beneath the subscapularis tendon. The inferior extension of the capsule is closely related to the axillary nerve at the surgical neck and this nerve is at risk in anteroinferior dislocations. It also means that proximally sited osteomyelitis may progress to septic arthritis. ``` Movements and muscles Flexion Anterior part of deltoid Pectoralis major Biceps Coracobrachialis Extension Posterior deltoid Teres major Latissimus dorsi Adduction Pectoralis major Latissimus dorsi Teres major Coracobrachialis Abduction Mid deltoid Supraspinatus Medial rotation Subscapularis Anterior deltoid Teres major Latissimus dorsi Lateral rotation Posterior deltoid Infraspinatus Teres minor ``` ``` Important anatomical relations Anteriorly Brachial plexus Axillary artery and vein Posterior Suprascapular nerve Suprascapular vessels Inferior Axillary nerve Circumflex humeral vessels ```

Answer 177

S2,3,4 keeps the poo up off the floor - POOdendal nerve Damage to the pudendal nerve is classically associated with faecal incontinence and it is for this reason that sacral neuromodulation is a popular treatment for the condition. Injury to the hypogastric autonomic nerves is an aetiological factor in the development of constipation. The pudendal nerve arises from nerve roots S2, S3 and S4 and exits the pelvis through the greater sciatic foramen. It re-enters the perineum through the lesser sciatic foramen. It travels inferior to give innervation to the anal sphincters and external urethral sphincter. It also provides cutaneous innervation to the region of perineum surrounding the anus and posterior vulva. Traction and compression of the pudendal nerve by the foetus in late pregnancy may result in late onset pudendal neuropathy which may be part of the process involved in the development of faecal incontinence.

Answer 178

This accessory vessel which usually lies at the inferior aspect of the gland is derived either from the brachiocephalic artery or the arch of the aorta. Thyroid gland Right and left lobes connected by isthmus Surrounded by sheath from pretracheal layer of deep fascia Apex: Lamina of thyroid cartilage Base: 4th-5th tracheal ring Pyramidal lobe: from isthmus May be attached to foramen caecum at the base of the tongue ``` Relations Anteromedially Sternothyroid Superior belly of omohyoid Sternohyoid Anterior aspect of sternocleidomastoid Posterolaterally Carotid sheath Medially Larynx Trachea Pharynx Oesophagus Cricothyroid muscle External laryngeal nerve (near superior thyroid artery) Recurrent laryngeal nerve (near inferior thyroid artery) Posterior Parathyroid glands Anastomosis of superior and inferior thyroid arteries Isthmus Anteriorly: Sternothyroids, sternohyoids, anterior jugular veins Posteriorly: 2nd, 3rd, 4th tracheal rings (attached via Ligament of Berry) ``` Blood Supply Arterial Superior thyroid artery (1st branch of external carotid) Inferior thyroid artery (from thyrocervical trunk) Thyroidea ima (in 10% of population -from brachiocephalic artery or aorta) Venous Superior and middle thyroid veins - into the IJV Inferior thyroid vein - into the brachiocephalic veins

Answer 179

The penis takes autonomic nerves from the nervi erigentes that lie near the seminal vesicles. These may be compromised by direct surgical trauma (such as use of diathermy in this area) and also by radiotherapy that is used in these patients pre operatively. The result is that up to 50% of patients may develop impotence following rectal cancer surgery. Penile erection Physiology of erection Autonomic Sympathetic nerves originate from T11-L2 and parasympathetic nerves from S2-4 join to form pelvic plexus. Parasympathetic discharge causes erection, sympathetic discharge causes ejaculation and detumescence. Somatic nerves Supplied by dorsal penile and pudendal nerves. Efferent signals are relayed from Onufs nucleus (S2-4) to innervate ischiocavernosus and bulbocavernosus muscles. Autonomic discharge to the penis will trigger the veno-occlusive mechanism which triggers the flow of arterial blood into the penile sinusoidal spaces. As the inflow increases the increased volume in this space will secondarily lead to compression of the subtunical venous plexus with reduced venous return. During the detumesence phase the arteriolar constriction will reduce arterial inflow and thereby allow venous return to normalise. Priapism Prolonged unwanted erection, in the absence of sexual desire, lasting more than 4 hours. Classification of priapism Low flow priapism Due to veno-occlusion (high intracavernosal pressures). Most common type Often painful Often low cavernosal flow If present for >4 hours requires emergency treatment High flow priapism Due to unregulated arterial blood flow. Usually presents as semi rigid painless erection Recurrent priapism Typically seen in sickle cell disease, most commonly of high flow type. Causes Intracavernosal drug therapies (e.g. for erectile dysfunction> Blood disorders such as leukaemia and sickle cell disease Neurogenic disorders such as spinal cord transection Trauma to penis resulting in arterio-venous malformations Tests Exclude sickle cell/ leukaemia Consider blood sampling from cavernosa to determine whether high or low flow (low flow is often hypoxic) Management Ice packs/ cold showers If due to low flow then blood may be aspirated from copora or try intracavernosal alpha adrenergic agonists. Delayed therapy of low flow priapism may result in erectile dysfunction.

Answer 180

Slipped upper femoral epiphysis is the commonest adolescent hip disorder. It occurs most commonly in obese males. It may often present as knee pain which is usually referred from the ipsilateral hip. The knee itself is normal. The hip often limits internal rotation. The diagnosis is easily missed. X-rays will show displacement of the femoral epiphysis and the degree of its displacement may be calculated using the Southwick angle. Treatment is directed at preventing further slippage which may result in avascular necrosis of the femoral head. Typically seen in obese male adolescents. Pain is often referred to the knee. Limitation to internal rotation is usually seen. Knee pain is usually present 2 months prior to hip slipping. Bilateral in 20%. Bed rest and non-weight bearing. Aim to avoid avascular necrosis. If severe slippage or risk of it occurring then percutaneous pinning of the hip may be required. X-rays will show the femoral head displaced and falling inferolaterally (like a melting ice cream cone) The Southwick angle gives indication of disease severity

Answer 181

Perthes disease This is a typical presentation for Perthes disease. X-ray may show flattening of the femoral head or fragmentation in more advanced cases. ``` Hip pain (may be referred to the knee) usually occurring between 5 and 12 years of age. Bilateral disease in 20%. Remove pressure from joint to allow normal development. Physiotherapy. Usually self-limiting if diagnosed and treated promptly. X-rays will show flattened femoral head. Eventually in untreated cases the femoral head will fragment. ```

Answer 182

Developmental dysplasia of the hip Developmental dysplasia of the hip. Usually diagnosed by Barlow and Ortolani tests in early childhood. Most Breech deliveries are also routinely subjected to USS of the hip joint. At this young age an arthrodesis may be preferable to hip replacement. Usually diagnosed in infancy by screening tests. May be bilateral, when disease is unilateral there may be leg length inequality. As disease progresses child may limp and then early onset arthritis. More common in extended breech babies. Splints and harnesses or traction. In later years osteotomy and hip realignment procedures may be needed. In arthritis a joint replacement may be needed. However, this is best deferred if possible as it will almost certainly require revision Initially no obvious change on plain films and USS gives best resolution until 3 months of age. On plain films Shentons line should form a smooth arc

Answer 183

CNV The most likely lesion to occur in the cerebello-pontine angle is an acoustic neuroma. The trigeminal nerve has a broad base and involvement of at least part of this nerve is the most likely initial finding. The defect may be subtle such as loss of the ipsilateral corneal reflex. Ipsilateral hearing loss will also occur. Untreated, progressive lesions, may ultimately affect cranial nerve roots in this region Cranial nerve lesions Olfactory nerve May be injured in basal skull fractures or involved in frontal lobe tumour extension. Loss of olfactory nerve function in relation to major CNS pathology is seldom an isolated event and thus it is poor localiser of CNS pathology. Optic nerve Problems with visual acuity may result from intra ocular disorders. Problems with the blood supply such as amaurosis fugax may produce temporary visual distortion. More important surgically is the pupillary response to light. The pupillary size may be altered in a number of disorders. Nerves involved in the resizing of the pupil connect to the pretectal nucleus of the high midbrain, bypassing the lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurones pass to the Edinger - Westphal nucleus, motor axons from here pass along with the oculomotor nerve. They synapse with ciliary ganglion neurones; the parasympathetic axons from this then innervate the iris and produce miosis. The miotic pupil is seen in disorders such as Horner's syndrome or opiate overdose. Mydriasis is the dilatation of the pupil in response to disease, trauma, drugs (or the dark!). It is pathological when light fails to induce miosis. The radial muscle is innervated by the sympathetic nervous system. Because the parasympathetic fibres travel with the oculomotor nerve they will be damaged by lesions affecting this nerve (e.g. cranial trauma). The response to light shone in one eye is usually a constriction of both pupils. This indicates intact direct and consensual light reflexes. When the optic nerve has an afferent defect the light shining on the affected eye will produce a diminished pupillary response in both eyes. Whereas light shone on the unaffected eye will produce a normal pupillary response in both eyes. This is referred to as the Marcus Gunn pupil and is seen in conditions such as optic neuritis. In a total CN II lesion shining the light in the affected eye will produce no response. Oculomotor nerve The pupillary effects are described above. In addition it supplies all ocular muscles apart from lateral rectus and superior oblique. Thus the affected eye will be deviated inferolaterally. Levator palpebrae superioris may also be impaired resulting in impaired ability to open the eye. Trochlear nerve The eye will not be able to look down. Trigeminal nerve Largest cranial nerve. Exits the brainstem at the pons. Branches are ophthalmic, maxillary and mandibular. Only the mandibular branch has both sensory and motor fibres. Branches converge to form the trigeminal ganglion (located in Meckels cave). It supplies the muscles of mastication and also tensor veli palatine, mylohyoid, anterior belly of digastric and tensor tympani. The detailed descriptions of the various sensory functions are described in other areas of the website. The corneal reflex is important and is elicited by applying a small tip of cotton wool to the cornea, a reflex blink should occur if it is intact. It is mediated by: the naso ciliary branch of the ophthalmic branch of the trigeminal (sensory component) and the facial nerve producing the motor response. Lesions of the afferent arc will produce bilateral absent blink and lesions of the efferent arc will result in a unilateral absent blink. Abducens nerve The affected eye will have a deficit of abduction. This cranial nerve exits the brainstem between the pons and medulla. It thus has a relatively long intra cranial course which renders it susceptible to damage in raised intra cranial pressure. Facial nerve Emerges from brainstem between pons and medulla. It controls muscles of facial expression and taste from the anterior 2/3 of the tongue. The nerve passes into the petrous temporal bone and into the internal auditory meatus. It then passes through the facial canal and exits at the stylomastoid foramen. It passes through the parotid gland and divides at this point. It does not innervate the parotid gland. Its divisions are considered in other parts of the website. Its motor fibres innervate orbicularis oculi to produce the efferent arm of the corneal reflex. In surgical practice it may be injured during parotid gland surgery or invaded by malignancies of the gland and a lower motor neurone on the ipsilateral side will result. Vestibulo-cochlear nerve Exits from the pons and then passes through the internal auditory meatus. It is implicated in sensorineural hearing loss. Individuals with sensorineural hearing loss will localise the sound in webers test to the normal ear. Rinnes test will be reduced on the affected side but should still work. These two tests will distinguish sensorineural hearing loss from conductive deafness. In the latter condition webers test will localise to the affected ear and Rinnes test will be impaired on the affected side. Surgical lesions affecting this nerve include CNS tumours and basal skull fractures. It may also be damaged by the administration of ototoxic drugs (of which gentamicin is the most commonly used in surgical practice). Glossopharyngeal nerve Exits the pons just above the vagus. Receives sensory fibres from posterior 1/3 tongue, tonsils, pharynx and middle ear (otalgia may occur following tonsillectomy). It receives visceral afferents from the carotid bodies. It supplies parasympathetic fibres to the parotid gland via the otic ganglion and motor function to stylopharyngeaus muscle. The sensory function of the nerve is tested using the gag reflex. Vagus nerve Leaves the medulla between the olivary nucleus and the inferior cerebellar peduncle. Passes through the jugular foramen and into the carotid sheath. Details of the functions of the vagus nerve are covered in the website under relevant organ sub headings. Accessory nerve Exists from the caudal aspect of the brainstem (multiple branches) supplies trapezius and sternocleidomastoid muscles. The distal portion of this nerve is most prone to injury during surgical procedures. Hypoglossal nerve: Emerges from the medulla at the preolivary sulcus, passes through the hypoglossal canal. It lies on the carotid sheath and passes deep to the posterior belly of digastric to supply muscles of the tongue (except palatoglossus). Its location near the carotid sheath makes it vulnerable during carotid endarterectomy surgery and damage will produce ipsilateral defect in muscle function.

Answer 184

Mnemonic for the Descending abdominal aorta branches from diaphragm to iliacs: 'Prostitutes Cause Sagging Swollen Red Testicles [in men] Living In Sin': ``` Phrenic [inferior] Celiac Superior mesenteric Suprarenal [middle] Renal Testicular ['in men' only] Lumbars Inferior mesenteric Sacral ``` The superior phrenic artery branches from the aorta in the thorax.

Answer 185

Non accidental injury Delayed presentation is unusual and should raise concern. In addition spiral fractures are usually the result of rotational injury which is not compatible with the mechanism proposed by the parent. Paediatric #s: Complete fracture Both sides of cortex are breached Toddlers fracture Oblique tibial fracture in infants Plastic deformity Stress on bone resulting in deformity without cortical disruption Greenstick fracture Unilateral cortical breach only Buckle fracture Incomplete cortical disruption resulting in periosteal haematoma only Growth plate fractures In paediatric practice fractures may also involve the growth plate and these injuries are classified according to the Salter- Harris system (given below): Type Injury pattern I Fracture through the physis only (x-ray often normal) II Fracture through the physis and metaphysis III Fracture through the physis and epiphyisis to include the joint IV Fracture involving the physis, metaphysis and epiphysis V Crush injury involving the physis (x-ray may resemble type I, and appear normal) As a general rule it is safer to assume that growth plate tenderness is indicative of an underlying fracture even if the x-ray appears normal. Injuries of Types III, IV and V will usually require surgery. Type V injuries are often associated with disruption to growth. Non accidental injury Delayed presentation Delay in attaining milestones Lack of concordance between proposed and actual mechanism of injury Multiple injuries Injuries at sites not commonly exposed to trauma Children on the at risk register Pathological fractures Genetic conditions, such as osteogenesis imperfecta, may cause pathological fractures. Osteogenesis imperfecta Defective osteoid formation due to congenital inability to produce adequate intercellular substances like osteoid, collagen and dentine. Failure of maturation of collagen in all the connective tissues. Radiology may show translucent bones, multiple fractures, particularly of the long bones, wormian bones (irregular patches of ossification) and a trefoil pelvis. Subtypes Type I The collagen is normal quality but insufficient quantity. Type II- Poor collagen quantity and quality. Type III- Collagen poorly formed. Normal quantity. Type IV- Sufficient collagen quantity but poor quality. ``` Osteopetrosis Bones become harder and more dense. Autosomal recessive condition. It is commonest in young adults. Radiology reveals a lack of differentiation between the cortex and the medulla described as marble bone. ```

Answer 186

Accidental fracture The mechanism fits with the fracture pattern and the presentation is not delayed. Growth plate fractures In paediatric practice fractures may also involve the growth plate and these injuries are classified according to the Salter- Harris system (given below): Type Injury pattern I Fracture through the physis only (x-ray often normal) II Fracture through the physis and metaphysis III Fracture through the physis and epiphyisis to include the joint IV Fracture involving the physis, metaphysis and epiphysis V Crush injury involving the physis (x-ray may resemble type I, and appear normal) As a general rule it is safer to assume that growth plate tenderness is indicative of an underlying fracture even if the x-ray appears normal. Injuries of Types III, IV and V will usually require surgery. Type V injuries are often associated with disruption to growth. Non accidental injury Delayed presentation Delay in attaining milestones Lack of concordance between proposed and actual mechanism of injury Multiple injuries Injuries at sites not commonly exposed to trauma Children on the at risk register Pathological fractures Genetic conditions, such as osteogenesis imperfecta, may cause pathological fractures. Osteogenesis imperfecta Defective osteoid formation due to congenital inability to produce adequate intercellular substances like osteoid, collagen and dentine. Failure of maturation of collagen in all the connective tissues. Radiology may show translucent bones, multiple fractures, particularly of the long bones, wormian bones (irregular patches of ossification) and a trefoil pelvis. Subtypes Type I The collagen is normal quality but insufficient quantity. Type II- Poor collagen quantity and quality. Type III- Collagen poorly formed. Normal quantity. Type IV- Sufficient collagen quantity but poor quality. ``` Osteopetrosis Bones become harder and more dense. Autosomal recessive condition. It is commonest in young adults. Radiology reveals a lack of differentiation between the cortex and the medulla described as marble bone. ```

Answer 187

Non accidental injury Posterior rib fractures are extremely unusual in neonates. The change in head size may be accounted for by hydrocephalus which may occur as a sequelae from head in Growth plate fractures In paediatric practice fractures may also involve the growth plate and these injuries are classified according to the Salter- Harris system (given below): Type Injury pattern I Fracture through the physis only (x-ray often normal) II Fracture through the physis and metaphysis III Fracture through the physis and epiphyisis to include the joint IV Fracture involving the physis, metaphysis and epiphysis V Crush injury involving the physis (x-ray may resemble type I, and appear normal) As a general rule it is safer to assume that growth plate tenderness is indicative of an underlying fracture even if the x-ray appears normal. Injuries of Types III, IV and V will usually require surgery. Type V injuries are often associated with disruption to growth. Non accidental injury Delayed presentation Delay in attaining milestones Lack of concordance between proposed and actual mechanism of injury Multiple injuries Injuries at sites not commonly exposed to trauma Children on the at risk register Pathological fractures Genetic conditions, such as osteogenesis imperfecta, may cause pathological fractures. Osteogenesis imperfecta Defective osteoid formation due to congenital inability to produce adequate intercellular substances like osteoid, collagen and dentine. Failure of maturation of collagen in all the connective tissues. Radiology may show translucent bones, multiple fractures, particularly of the long bones, wormian bones (irregular patches of ossification) and a trefoil pelvis. Subtypes Type I The collagen is normal quality but insufficient quantity. Type II- Poor collagen quantity and quality. Type III- Collagen poorly formed. Normal quantity. Type IV- Sufficient collagen quantity but poor quality. ``` Osteopetrosis Bones become harder and more dense. Autosomal recessive condition. It is commonest in young adults. Radiology reveals a lack of differentiation between the cortex and the medulla described as marble bone. ```

Answer 188

The sural nerve is closely related and damage to this structure is a major cause of litigation. The other structures may all be injured but the risks are lower. Boundaries of the popliteal fossa Laterally Biceps femoris above, lateral head of gastrocnemius and plantaris below Medially Semimembranosus and semitendinosus above, medial head of gastrocnemius below Floor Popliteal surface of the femur, posterior ligament of knee joint and popliteus muscle Roof Superficial and deep fascia ``` Contents Popliteal artery and vein Small saphenous vein Common peroneal nerve Tibial nerve Posterior cutaneous nerve of the thigh Genicular branch of the obturator nerve Lymph nodes ```

Answer 189

The ureter lies anterior to L2 to L5 and stones may be visualised at these points, they may also be identified over the sacro-iliac joints. Ureter 25-35 cm long Muscular tube lined by transitional epithelium Surrounded by thick muscular coat. Becomes 3 muscular layers as it crosses the bony pelvis Retroperitoneal structure overlying transverse processes L2-L5 Lies anterior to bifurcation of iliac vessels Blood supply is segmental; renal artery, aortic branches, gonadal branches, common iliac and internal iliac Lies beneath the uterine artery

Answer 190

The quadriceps femoris lies in the anterior compartment. Compartments of the thigh Formed by septae passing from the femur to the fascia lata. Anterior compartment Femora N,l Iliacus, Tensor fasciae latae, Sartorius, Quadriceps femoris, Femoral artery Medial compartment Obturator N Adductor longus/magnus/brevis, Gracilis, Obturator externus, Profunda femoris artery and obturator artery ``` Posterior compartment (2 layers) Sciatic Semimembranosus Semitendinosus Biceps femoris Branches of Profunda femoris artery ``` Compartments of the lower leg Separated by the interosseous membrane (anterior and posterior compartments), anterior fascial septum (separate anterior and lateral compartments) and posterior fascial septum (separate lateral and posterior compartments) ``` Anterior compartment Deep peroneal nerve Tibialis anterior Extensor digitorum longus Extensor hallucis longus Peroneus tertius Anterior tibial artery ``` Posterior compartment Tibial N Muscles: deep and superficial compartments (separated by deep transverse fascia) Deep: Flexor hallucis longus, Flexor digitalis longus, Tibialis posterior, Popliteus Superficial: Gastrocnemius, Soleus, Plantaris Posterior tibial Lateral compartment Superficial peroneal N Peroneus longus/brevis Peroneal artery

Answer 191

The serratus anterior muscle is supplied by the long thoracic nerve which runs along the surface of serratus anterior and is liable to injury during nodal dissection. Although pectoralis minor is divided during a Patey mastectomy (now seldom performed) it is rare for this alone to produce winging of the scapula Long thoracic nerve Derived from ventral rami of C5, C6, and C7 (close to their emergence from intervertebral foramina) It runs downward and passes either anterior or posterior to the middle scalene muscle It reaches upper tip of serratus anterior muscle and descends on outer surface of this muscle, giving branches into it Winging of Scapula occurs in long thoracic nerve injury (most common) or from spinal accessory nerve injury (which denervates the trapezius) or a dorsal scapular nerve injury

Answer 192

Because the kidney is present, rather than absent, the adrenal will usual develop and in the normal location. Adrenal gland embryology First detected at 6 weeks' gestation, the adrenal cortex is derived from the mesoderm of the posterior abdominal wall. Steroid secretion from the fetal cortex begins shortly thereafter. Adult-type zona glomerulosa and fasciculata are detected in fetal life but make up only a small proportion of the gland, and the zona reticularis is not present at all. The fetal cortex predominates throughout fetal life. The adrenal medulla is of ectodermal origin, arising from neural crest cells that migrate to the medial aspect of the developing cortex. The fetal adrenal gland is relatively large. At 4 months' gestation, it is 4 times the size of the kidney; however, at birth, it is a third of the size of the kidney. This occurs because of the rapid regression of the fetal cortex at birth. It disappears almost completely by age 1 year; by age 4-5 years, the permanent adult-type adrenal cortex has fully developed. Anatomic anomalies of the adrenal gland may occur. Because the development of the adrenals is closely associated with that of the kidneys, agenesis of an adrenal gland is usually associated with ipsilateral agenesis of the kidney, and fused adrenal glands (whereby the 2 glands join across the midline posterior to the aorta) are also associated with a fused kidney. Adrenal hypoplasia occurs in the following 2 forms: (1) hypoplasia or absence of the fetal cortex with a poorly formed medulla and (2) disorganized fetal cortex and medulla with no permanent cortex present. Adrenal heterotopia describes a normal adrenal gland in an abnormal location, such as within the renal or hepatic capsules. Accessory adrenal tissue (adrenal rests), which is usually comprised only of cortex but seen combined with medulla in some cases, is most commonly located in the broad ligament or spermatic cord but can be found anywhere within the abdomen. Even intracranial adrenal rests have been reported

Answer 193

The deep peroneal nerve lies in the anterior compartment. The tibial nerve lies medially. At its termination it lies deep to the flexor retinaculum. Posterior tibial artery Larger terminal branch of the popliteal artery Terminates by dividing into the medial and lateral plantar arteries Accompanied by two veins throughout its length Position of the artery corresponds to a line drawn from the lower angle of the popliteal fossa, at the level of the neck of the fibula, to a point midway between the medial malleolus and the most prominent part of the heel Relations of the posterior tibial artery Proximal to distal Anteriorly Tibialis posterior Flexor digitorum longus Posterior surface of tibia and ankle joint Posterior Tibial nerve 2.5 cm distal to its origin Fascia overlying the deep muscular layer Proximal part covered by gastrocnemius and soleus Distal part covered by skin and fascia

Answer 194

The ulnar nerve and artery lie adjacent to the pisiform bone. The capitate bone articulates with the lunate, scaphoid, hamate and trapezoid bones, which are therefore closely related to it. Capitate bone This is the largest of the carpal bones. It is centrally placed with a rounded head set into the cavities of the lunate and scaphoid bones. Flatter articular surfaces are present for the hamate medially and the trapezoid laterally. Distally the bone articulates predominantly with the middle metacarpal.

Answer 195

The chorda tympani runs medially to the pars flaccida. The relationship is shown from the medial aspect in the dissection below. The ear is composed of three anatomically distinct regions. External ear Auricle is composed of elastic cartilage covered by skin. The lobule has no cartilage and contains fat and fibrous tissue. External auditory meatus is approximately 2.5cm long. Lateral third of the external auditory meatus is cartilaginous and the medial two thirds is bony. The region is innervated by the greater auricular nerve. The auriculotemporal branch of the trigeminal nerve supplies most the of external auditory meatus and the lateral surface of the auricle. Middle ear Space between the tympanic membrane and cochlea. The aditus leads to the mastoid air cells is the route through which middle ear infections may cause mastoiditis. Anteriorly the eustacian tube connects the middle ear to the naso pharynx. The tympanic membrane consists of: Outer layer of stratified squamous epithelium. Middle layer of fibrous tissue. Inner layer of mucous membrane continuous with the middle ear. The tympanic membrane is approximately 1cm in diameter. The chorda tympani nerve passes on the medial side of the pars flaccida. The middle ear is innervated by the glossopharyngeal nerve and pain may radiate to the middle ear following tonsillectomy. Ossicles Malleus attaches to the tympanic membrane (the Umbo). Malleus articulates with the incus (synovial joint). Incus attaches to stapes (another synovial joint). Internal ear Cochlea, semi circular canals and vestibule Organ of corti is the sense organ of hearing and is located on the inside of the cochlear duct on the basilar membrane. Vestibule accommodates the utricule and the saccule. These structures contain endolymph and are surrounded by perilymph within the vestibule. The semicircular canals lie at various angles to the petrous temporal bone. All share a common opening into the vestibule.

Answer 196

The spinal accessory nerve innervates trapezius. The entire muscle will retract the scapula. However, its upper and lower fibres act together to upwardly rotate it. Shoulder joint Shallow synovial ball and socket type of joint. It is an inherently unstable joint, but is capable to a wide range of movement. Stability is provided by muscles of the rotator cuff that pass from the scapula to insert in the greater tuberosity (all except sub scapularis-lesser tuberosity). Glenoid labrum Fibrocartilaginous rim attached to the free edge of the glenoid cavity Tendon of the long head of biceps arises from within the joint from the supraglenoid tubercle, and is fused at this point to the labrum. The long head of triceps attaches to the infraglenoid tubercle Fibrous capsule Attaches to the scapula external to the glenoid labrum and to the labrum itself (postero-superiorly) Attaches to the humerus at the level of the anatomical neck superiorly and the surgical neck inferiorly Anteriorly the capsule is in contact with the tendon of subscapularis, superiorly with the supraspinatus tendon, and posteriorly with the tendons of infraspinatus and teres minor. All these blend with the capsule towards their insertion. Two defects in the fibrous capsule; superiorly for the tendon of biceps. Anteriorly there is a defect beneath the subscapularis tendon. The inferior extension of the capsule is closely related to the axillary nerve at the surgical neck and this nerve is at risk in anteroinferior dislocations. It also means that proximally sited osteomyelitis may progress to septic arthritis. ``` Movements and muscles - Flexion Anterior part of deltoid Pectoralis major Biceps Coracobrachialis ``` - Extension Posterior deltoid Teres major Latissimus dorsi - Adduction Pectoralis major Latissimus dorsi Teres major Coracobrachialis - Abduction Mid deltoid Supraspinatus - Medial rotation Subscapularis Anterior deltoid Teres major Latissimus dorsi - Lateral rotation Posterior deltoid Infraspinatus Teres minor ``` Important anatomical relations - Anteriorly Brachial plexus Axillary artery and vein - Posterior Suprascapular nerve Suprascapular vessels - Inferior Axillary nerve Circumflex humeral vessels ```

Answer 197

The thoracic duct lies within the posterior and superior mediastinum. Mediastinum Region between the pulmonary cavities. It is covered by the mediastinal pleura. It does not contain the lungs. It extends from the thoracic inlet superiorly to the diaphragm inferiorly. ``` Mediastinal regions Superior mediastinum (between manubriosternal angle and T4/5) Middle mediastinum Posterior mediastinum Anterior mediastinum ``` ``` - Superior mediastinum Superior vena cava Brachiocephalic veins Arch of aorta Thoracic duct Trachea Oesophagus Thymus Vagus nerve Left recurrent laryngeal nerve Phrenic nerve ``` - Anterior mediastinum Thymic remnants Lymph nodes Fat ``` - Middle mediastinum Pericardium Heart Aortic root Arch of azygos vein Main bronchi ``` ``` - Posterior mediastinum Oesophagus Thoracic aorta Azygos vein Thoracic duct Vagus nerve Sympathetic nerve trunks Splanchnic nerves ```

Answer 198

The arterial supply to the prostate gland is from the inferior vesical artery, it is a branch of the prostatovesical artery. The prostatovesical artery usually arises from the internal pudendal and inferior gluteal arterial branches of the internal iliac artery. The prostate gland is approximately the shape and size of a walnut and is located inferior to the bladder. It is separated from the rectum by Denonvilliers fascia and its blood supply is derived from the internal iliac vessels (via inferior vesical artery). The internal sphincter lies at the apex of the gland and may be damaged during prostatic surgery, affected individuals may complain of retrograde ejaculation. ``` Summary of prostate gland Arterial supply Inferior vesical artery (from internal iliac) Venous drainage Prostatic venous plexus (to paravertebral veins) Lymphatic drainage Internal iliac nodes Innervation Inferior hypogastric plexus Dimensions Transverse diameter (4cm) AP diameter (2cm) Height (3cm) ``` ``` Lobes Posterior lobe: posterior to urethra Median lobe: posterior to urethra, in between ejaculatory ducts Lateral lobes x 2 Isthmus ``` ``` Zones Peripheral zone: subcapsular portion of posterior prostate. Most prostate cancers are here Central zone Transition zone Stroma ``` ``` Relations - Anterior Pubic symphysis Prostatic venous plexus - Posterior Denonvilliers fascia Rectum Ejaculatory ducts - Lateral Venous plexus (lies on prostate) Levator ani (immediately below the puboprostatic ligaments) ```

Answer 199

None of the above No single one of the above nerves is responsible for direct cardiac innervation (which those who have handled the heart surgically will appreciate). The heart receives its nerves from the superficial and deep cardiac plexuses. The cardiac plexuses send small branches to the heart along the major vessels, continuing with the right and left coronary arteries. The vagal efferent fibres emerge from the brainstem in the roots of the vagus and accessory nerves, and run to ganglia in the cardiac plexuses and within the heart itself. The background vagal discharge serves to limit heart rate, and loss of this background vagal tone accounts for the higher resting heart rate seen following cardiac transplant. Sinoatrial node Located in the wall of the right atrium in the upper part of the sulcus terminalis from which it extends anteriorly over the opening of the superior vena cava. In most cases it is supplied by the right coronary artery. It has a complicated nerve supply from the cardiac nerve plexus that takes both sympathetic and parasympathetic fibres that run alongside the main vessels.

Answer 200

Kocher criteria 1. Non weight bearing on affected side 2. ESR > 40 mm/hr 3. Fever 4. WBC count of >12,000 mm3 - When 4/4 criteria are met, there is a 99% chance that the child has septic arthritis The Kocher criteria do not consider blood culture results. Septic arthritis Staph aureus commonest organism Urgent washout and antibiotics otherwise high risk of joint destruction Diagnosis Plain x-rays Consider aspiration Utilise the Kocher criteria (see below) Kocher criteria: 1. Non weight bearing on affected side 2. ESR > 40 mm/hr 3. Fever 4. WBC count of >12,000 mm3 - when 4/4 criteria are met, there is a 99% chance that the child has septic arthritis Treatment Surgical drainage of the affected joint is required, this should be done as soon as possible since permanent damage to the joint may occur. In some cases repeated procedures are necessary. Appropriate intravenous antibiotics should be administered.

Answer 201

The ankle reflex is elicited by tapping the Achilles tendon with a tendon hammer. It tests the S1 and S2 nerve roots. It is typically delayed in L5 and S1 disk prolapses.

Answer 202

The piriformis muscle is an important anatomical landmark in the gluteal region. The following structures are closely related: Sciatic nerve Inferior gluteal artery and nerve Superior gluteal artery and nerve The medial femoral circumflex artery runs deep to quadratus femoris. Gluteal muscles Gluteus maximus: inserts to gluteal tuberosity of the femur and iliotibial tract Gluteus medius: attach to lateral greater trochanter Gluteus minimis: attach to anterior greater trochanter All extend and abduct the hip ``` Deep lateral hip rotators Piriformis Gemelli Obturator internus Quadratus femoris ``` ``` Nerves Superior gluteal nerve (L5, S1) Gluteus medius Gluteus minimis Tensor fascia lata ``` Inferior gluteal nerve Gluteus maximus Damage to the superior gluteal nerve will result in the patient developing a Trendelenberg gait. Affected patients are unable to abduct the thigh at the hip joint. During the stance phase, the weakened abductor muscles allow the pelvis to tilt down on the opposite side. To compensate, the trunk lurches to the weakened side to attempt to maintain a level pelvis throughout the gait cycle. The pelvis sags on the opposite side of the lesioned superior gluteal nerve.

Answer 203

Middle Cardiac Vein Heart anatomy The walls of each cardiac chamber comprise: Epicardium Myocardium Endocardium Cardiac muscle is attached to the cardiac fibrous skeleton. Relations The heart and roots of the great vessels within the pericardial sac are related to the posterior aspect of the sternum, medial ends of the 3rd to 5th ribs on the left and their associated costal cartilages. The heart and pericardial sac are situated obliquely two thirds to the left and one third to the right of the median plane. The pulmonary valve lies at the level of the left third costal cartilage. The mitral valve lies at the level of the fourth costal cartilage. Coronary sinus This lies in the posterior part of the coronary groove and receives blood from the cardiac veins. The great cardiac vein lies at its left and the middle and small cardiac veins lie on its right. The smallest cardiac vein (anterior cardiac vein) drains into the right atrium directly. Aortic sinus Right coronary artery arises from the right aortic sinus, the left is derived from the left aortic sinus, which lies posteriorly. Features of the left ventricle as opposed to the right Structure Left Ventricle A-V Valve Mitral (double leaflet) Walls Twice as thick as right Trabeculae carnae Much thicker and more numerous Right coronary artery The RCA supplies: Right atrium Diaphragmatic part of the right ventricle Usually the posterior third of the interventricular septum The sino atrial node (60% cases) The atrio ventricular node (80% cases) Left coronary artery The LCA supplies: Left atrium Most of left ventricle Part of the right ventricle Anterior two thirds of the inter ventricular septum The sino atrial node (remaining 40% cases) Innervation of the heart Autonomic nerve fibres from the superficial and deep cardiac plexus. These lie anterior to the bifurcation of the trachea, posterior to the ascending aorta and superior to the bifurcation of the pulmonary trunk. The parasympathetic supply to the heart is from presynaptic fibres of the vagus nerves.

Answer 204

The trochlear nerve has a relatively long intracranial course and this makes it vulnerable to injury in head trauma. Head trauma is the commonest cause of an acute fourth nerve palsy. A 4th nerve palsy is the commonest cause of a vertical diplopia. The diplopia is at its worst when the eye looks medially which it usually does as part of the accommodation reflex when walking down stairs. Oculomotor nerve Large nucleus at the midbrain Fibres pass through the red nucleus and the pyramidal tract; through the cavernous sinus into the orbit Ptosis Eye down and out Unable to move the eye superiorly, inferiorly, medially Pupil fixed and dilated ``` Trochlear nerve Longest intracranial course Only nerve to exit the dorsal aspect of brainstem Nucleus at midbrain, passes between the posterior cerebral and superior cerebellar arteries, through the cavernous sinus into the orbit Vertical diplopia (diplopia on descending the stairs) Unable to look down and in ``` Abducens nerve Nucleus lies in the mid pons Convergence of eyes in primary position Lateral diplopia towards side of lesion Eye deviates medially

Answer 205

The extensor hallucis longus tendon lies medial to the dorsalis pedis artery. Arches of the foot The foot is conventionally considered to have two arches. The longitudinal arch is higher on the medial than on the lateral side. The posterior part of the calcaneum forms a posterior pillar to support the arch. The lateral part of this structure passes via the cuboid bone and the lateral two metatarsal bones. The medial part of this structure is more important. The head of the talus marks the summit of this arch, located between the sustentaculum tali and the navicular bone. The anterior pillar of the medial arch is composed of the navicular bone, the three cuneiforms and the medial three metatarsal bones. The transverse arch is situated on the anterior part of the tarsus and the posterior part of the metatarsus. The cuneiforms and metatarsal bases narrow inferiorly, which contributes to the shape of the arch. Intertarsal joints - Sub talar joint Formed by the cylindrical facet on the lower surface of the body of the talus and the posterior facet on the upper surface of the calcaneus. The facet on the talus is concave anteroposteriorly, the other is convex. The synovial cavity of this joint does not communicate with any other joint. - Talocalcaneonavicular joint The anterior part of the socket is formed by the concave articular surface of the navicular bone, posteriorly by the upper surface of the sustentaculum tali. The talus sits within this socket - Calcaneocuboid joint Highest point in the lateral part of the longitudinal arch. The lower aspect of this joint is reinforced by the long plantar and plantar calcaneocuboid ligaments. - Transverse tarsal joint The talocalcaneonavicular joint and the calcaneocuboid joint extend across the tarsus in an irregular transverse plane, between the talus and calcaneus behind and the navicular and cuboid bones in front. This plane is termed the transverse tarsal joint. - Cuneonavicular joint Formed between the convex anterior surface of the navicular bone and the concave surface of the the posterior ends of the three cuneiforms. Intercuneiform joints Between the three cuneiform bones. - Cuneocuboid joint Between the circular facets on the lateral cuneiform bone and the cuboid. This joint contributes to the tarsal part of the transverse arch. Nerves in the foot Lateral plantar nerve Passes anterolaterally towards the base of the 5th metatarsal between flexor digitorum brevis and flexor accessorius. On the medial aspect of the lateral plantar artery. At the base of the 5th metatarsal it splits into superficial and deep branches. Medial plantar nerve Passes forwards with the medial plantar artery under the cover of the flexor retinaculum to the interval between abductor hallucis and flexor digitorum brevis on the sole of the foot. Plantar arteries Arise under the cover of the flexor retinaculum, midway between the tip of the medial malleolus and the most prominent part of the medial side of the heel. Medial plantar artery. Passes forwards medial to medial plantar nerve in the space between abductor hallucis and flexor digitorum brevis.Ends by uniting with a branch of the 1st plantar metatarsal artery. Lateral plantar artery. Runs obliquely across the sole of the foot. It lies lateral to the lateral plantar nerve. At the base of the 5th metatarsal bone it arches medially across the foot on the metatarsals Dorsalis pedis artery This vessel is a direct continuation of the anterior tibial artery. It commences on the front of the ankle joint and runs to the proximal end of the first metatarsal space. Here is gives off the arcuate artery and continues forwards as the first dorsal metatarsal artery. It is accompanied by two veins throughout its length. It is crossed by the extensor hallucis brevis

Answer 206

The median nerve may be injured proximal to the flexor retinaculum. This will result in loss of abductor pollicis brevis, flexor pollicis brevis, opponens pollicis and the first and second lumbricals. When the patient is asked to close the hand slowly there is a lag of the index and middle fingers reflecting the impaired lumbrical muscle function. The sensory changes are minor and do not extend to the dorsal aspect of the thenar eminence. Abductor pollicis longus will contribute to thumb abduction (and is innervated by the posterior interosseous nerve) and therefore abduction will be weaker than prior to the injury. The median nerve is formed by the union of a lateral and medial root respectively from the lateral (C5,6,7) and medial (C8 and T1) cords of the brachial plexus; the medial root passes anterior to the third part of the axillary artery. The nerve descends lateral to the brachial artery, crosses to its medial side (usually passing anterior to the artery). It passes deep to the bicipital aponeurosis and the median cubital vein at the elbow. It passes between the two heads of the pronator teres muscle, and runs on the deep surface of flexor digitorum superficialis (within its fascial sheath). Near the wrist it becomes superficial between the tendons of flexor digitorum superficialis and flexor carpi radialis, deep to palmaris longus tendon. It passes deep to the flexor retinaculum to enter the palm, but lies anterior to the long flexor tendons within the carpal tunnel. Branches: - Upper arm No branches, although the nerve commonly communicates with the musculocutaneous nerve ``` - Forearm Pronator teres Flexor carpi radialis Palmaris longus Flexor digitorum superficialis Flexor pollicis longus Flexor digitorum profundus (only the radial half) ``` ``` - Distal forearm Palmar cutaneous branch Hand (Motor) Motor supply (LOAF) Lateral 2 lumbricals Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis ``` - Hand (Sensory) Over thumb and lateral 2 ½ fingers On the palmar aspect this projects proximally, on the dorsal aspect only the distal regions are innervated with the radial nerve providing the more proximal cutaneous innervation. Patterns of damage Damage at wrist e.g. carpal tunnel syndrome paralysis and wasting of thenar eminence muscles and opponens pollicis (ape hand deformity) sensory loss to palmar aspect of lateral (radial) 2 ½ fingers Damage at elbow, as above plus: unable to pronate forearm weak wrist flexion ulnar deviation of wrist Anterior interosseous nerve (branch of median nerve) leaves just below the elbow results in loss of pronation of forearm and weakness of long flexors of thumb and index finger

Answer 207

The external branch of the superior laryngeal nerve innervates the cricothyroid muscle. Recurrent laryngeal nerve - Branch of the vagus nerve Innervates: all intrinsic larynx muscles (excluding cricothyroid) Path: Right Arises anterior to the subclavian artery and ascends obliquely next to the trachea, behind the common carotid artery It is either anterior or posterior to the inferior thyroid artery Left Arises left to the arch of the aorta Winds below the aorta Ascends along the side of the trachea Then both Pass in a groove between the trachea and oesophagus Enters the larynx behind the articulation between the thyroid cartilage and cricoid Distributed to larynx muscles Branches to Cardiac plexus Mucous membrane and muscular coat of the oesophagus and trachea Innervates Intrinsic larynx muscles (excluding cricothyroid)

Answer 208

The ureter develops from the mesonephric duct. The mesonephric duct is associated with the metanephric duct that develops within the metenephrogenic blastema. This forms the site of the ureteric bud which branches off the mesonephric duct. Ureter 25-35 cm long Muscular tube lined by transitional epithelium Surrounded by thick muscular coat. Becomes 3 muscular layers as it crosses the bony pelvis Retroperitoneal structure overlying transverse processes L2-L5 Lies anterior to bifurcation of iliac vessels Blood supply is segmental; renal artery, aortic branches, gonadal branches, common iliac and internal iliac Lies beneath the uterine artery

Answer 209

Right parieto-temporal craniotomy A unilateral dilated pupil is a classic sign of transtentorial herniation. The medial aspect of the temporal lobe (uncus) herniates across the tentorium and causes pressure on the ipsilateral oculomotor nerve, interrupting parasympathetic input to the eye and resulting in a dilated pupil. In addition the brainstem is compressed. As the ipsilateral oculomotor nerve is being compressed, craniotomy (rather than Burr Holes) should be made on the ipsilateral side. Patients who suffer head injuries should be managed according to ATLS principles and extra cranial injuries should be managed alongside cranial trauma. Inadequate cardiac output will compromise CNS perfusion irrespective of the nature of the cranial injury. Types of traumatic brain injury Extradural haematoma Bleeding into the space between the dura mater and the skull. Often results from acceleration-deceleration trauma or a blow to the side of the head. The majority of extradural haematomas occur in the temporal region where skull fractures cause a rupture of the middle meningeal artery. Features Raised intracranial pressure Some patients may exhibit a lucid interval Subdural haematoma Bleeding into the outermost meningeal layer. Most commonly occur around the frontal and parietal lobes. May be either acute or chronic. Risk factors include old age and alcoholism. Slower onset of symptoms than a extradural haematoma. Subarachnoid haemorrhage Usually occurs spontaneously in the context of a ruptured cerebral aneurysm, but may be seen in association with other injuries when a patient has sustained a traumatic brain injury. Pathophysiology Primary brain injury may be focal (contusion/ haematoma) or diffuse (diffuse axonal injury) Diffuse axonal injury occurs as a result of mechanical shearing following deceleration, causing disruption and tearing of axons Intra-cranial haematomas can be extradural, subdural or intracerebral, while contusions may occur adjacent to (coup) or contralateral (contre-coup) to the side of impact Secondary brain injury occurs when cerebral oedema, ischaemia, infection, tonsillar or tentorial herniation exacerbates the original injury. The normal cerebral auto regulatory processes are disrupted following trauma rendering the brain more susceptible to blood flow changes and hypoxia The Cushings reflex (hypertension and bradycardia) often occurs late and is usually a pre terminal event Management Where there is life threatening rising ICP such as in extra dural haematoma and whilst theatre is prepared or transfer arranged use of IV mannitol/ frusemide may be required. Diffuse cerebral oedema may require decompressive craniotomy Exploratory Burr Holes have little management in modern practice except where scanning may be unavailable and to thus facilitate creation of formal craniotomy flap Depressed skull fractures that are open require formal surgical reduction and debridement, closed injuries may be managed non operatively if there is minimal displacement. ICP monitoring is appropriate in those who have GCS 3-8 and normal CT scan. ICP monitoring is mandatory in those who have GCS 3-8 and abnormal CT scan. Hyponatraemia is most likely to be due to syndrome of inappropriate ADH secretion. Minimum of cerebral perfusion pressure of 70mmHg in adults. Minimum cerebral perfusion pressure of between 40 and 70 mmHg in children.

Answer 210

Total hip replacement In otherwise fit patients aged over 70, the best long term functional outcomes are obtained with total hip arthroplasty. Neck of femur (NOF) fracture is a common orthopaedic presentation, with over 65000 fractures in the UK per year. Like many orthopaedic injuries, there is a bimodal age distribution. It is imperative to distinguish between the high energy injury in a young patient, and the low energy osteoporotic fracture in the elderly, as their management aims are very different: Young patient - Usually high energy trauma (e.g road traffic accident, horse riding) and needs treating in accordance with Advanced Trauma Life Support (ATLS) principles. Will often have associated injuries. Aim is to retain the patients own anatomy, and optimise their function. Elderly patient - Predominantly female, fall from standing height (fragility fracture). Often patients have multiple comorbidities that will ultimately dictate their prognosis. Aim of orthopaedic treatment is to immediately regain patient mobility so that morbidity (infection, thromboembolic events, pressure sores etc) and mortality associated with prolonged bed rest is avoided. Left untreated, a neck of femur fracture can be considered a terminal event. Historically, mortality associated with elderly hip fracture is 10% at one month, and 30% at one year. However, this has been improved in the UK with the introduction of multidisciplinary, orthogeriatric lead care and the National Hip Fracture Database and Best Practice Tariff. Pertinent anatomy Osteology - normal neck-shaft angle is 130 +/- 7 degrees, and 10 +/- 7 degrees of neck anteversion. Vascular supply - The predominant blood supply to the femoral head and neck is from the medial and lateral femoral circumflex arteries (branches of profunda femoris). These anastomose and pierce the joint capsule at the base of the neck, mainly posteriorly. There is a small vascular contribution from the artery of the ligament teres. Understanding the blood supply is fundamental to the decision making process in treating NOF fractures. Presentation and initial management Typically, patients present with pain in the hip/groin, a shortened, abducted, externally rotated leg (due to the unopposed pull of the muscles that act across the hip joint) and the inability to straight-leg-raise. With undisplaced fractures, signs are more subtle. High energy injuries should be treated in line with ATLS principles. All patients should be fluid resuscitated, have adequate pain relief (often with a fascio-iliiaca nerve block), and be optimised for surgery. In addition, elderly patients should be assessed by an orthogeriatrician. Imaging Anteroposterior and cross-table lateral plain radiographs are sufficient to diagnose the majority of NOF fractures. If the fracture extends below the level of the lesser trochanter, or there is any possibility of pathological fracture, full length femur views are essential to plan surgery. Where there is a high index of suspicion of fracture, but plain radiographs are inconclusive, gold standard investigation is MRI. However, if unavailable within 24 hours, or if the patient will not tolerate MRI, CT is appropriate. The majority of fractures can be seen with modern CT techniques, and so this is becoming first line in many hospitals. Classification There has been a move away from named classification systems towards descriptive classification systems. Two main types of NOF exist: Intra-capsular, and extra-capsular. Extra-capsular fractures are further divided into pertrochanteric or subtrochanteric (within 5cm distal to the lesser trochanter). All fractures are then described as undisplaced, minimally displaced, or displaced. Femoral neck and head blood supply disruption is common with intracapsular NOF fractures, and rare with extracapsular fractures. This fundamental principle underpins the practise of arthroplasty for intracapsular fractures, and fixation for extracapsular fractures. If you wish to use a named classification system, the most commonly used are below: Elderly intracapsular - Garden Classification Young intrasapsular - Pauvels Classification Intertrochanteric - Evans Subtrochanteric - Russell Taylor Treatment In general, NOF fractures are treated operatively except if the patient is deemed unlikely to survive an anaesthetic. Best Practice Tarif (BPT) dictates that surgery should happen within 36 hours, as delay of greater than 48 hours is associated with increased morbidity and mortality. * The priority with the young patient is to retain the femoral head if possible, even with a displaced intracapsular fracture. The risk of avascular necrosis and non-union (and therefore revision surgery) associated with internal fixation needs weighing up against the sequelae of total hip replacement in the young (wear, dislocation, revision). Discussion is necessary with the patient, on a case by case basis. ** Undisplaced fractures in the elderly can be treated with internal fixation, often with cannulated screws. This is appropriate for valgus impacted subcapital fractures which are inherently stable, to prevent secondary displacement. This does still carry the risk of AVN or non-union, and therefore a future revision. For this reason, many surgeons advocate arthroplasty as a single surgery. *** NICE guidance - patients who fulfil these criteria should be offered total hip replacement which conveys better function and prosthetic survivorship, compared with hemiarthroplasty, but at an increased risk of dislocation. * Intertrochanteric fractures vary greatly in their stability. If the trochanter (and therefore lateral wall), and medial calcar is in tact, then the fracture configuration bears stability. This can be treated with a DHS, as collapse of the fracture is predictable. Where either or both structures are involved in the fracture, stability becomes compromised and many surgeons will favour using an intramedullary device. This is an ongoing debate, and difficult to test in an exam setting.

Answer 211

Intramedullary devices are normally recommended for reverse oblique, transverse subtrochanteric fractures. Neck of femur (NOF) fracture is a common orthopaedic presentation, with over 65000 fractures in the UK per year. Like many orthopaedic injuries, there is a bimodal age distribution. It is imperative to distinguish between the high energy injury in a young patient, and the low energy osteoporotic fracture in the elderly, as their management aims are very different: Young patient - Usually high energy trauma (e.g road traffic accident, horse riding) and needs treating in accordance with Advanced Trauma Life Support (ATLS) principles. Will often have associated injuries. Aim is to retain the patients own anatomy, and optimise their function. Elderly patient - Predominantly female, fall from standing height (fragility fracture). Often patients have multiple comorbidities that will ultimately dictate their prognosis. Aim of orthopaedic treatment is to immediately regain patient mobility so that morbidity (infection, thromboembolic events, pressure sores etc) and mortality associated with prolonged bed rest is avoided. Left untreated, a neck of femur fracture can be considered a terminal event. Historically, mortality associated with elderly hip fracture is 10% at one month, and 30% at one year. However, this has been improved in the UK with the introduction of multidisciplinary, orthogeriatric lead care and the National Hip Fracture Database and Best Practice Tariff. Pertinent anatomy Osteology - normal neck-shaft angle is 130 +/- 7 degrees, and 10 +/- 7 degrees of neck anteversion. Vascular supply - The predominant blood supply to the femoral head and neck is from the medial and lateral femoral circumflex arteries (branches of profunda femoris). These anastomose and pierce the joint capsule at the base of the neck, mainly posteriorly. There is a small vascular contribution from the artery of the ligament teres. Understanding the blood supply is fundamental to the decision making process in treating NOF fractures. Presentation and initial management Typically, patients present with pain in the hip/groin, a shortened, abducted, externally rotated leg (due to the unopposed pull of the muscles that act across the hip joint) and the inability to straight-leg-raise. With undisplaced fractures, signs are more subtle. High energy injuries should be treated in line with ATLS principles. All patients should be fluid resuscitated, have adequate pain relief (often with a fascio-iliiaca nerve block), and be optimised for surgery. In addition, elderly patients should be assessed by an orthogeriatrician. Imaging Anteroposterior and cross-table lateral plain radiographs are sufficient to diagnose the majority of NOF fractures. If the fracture extends below the level of the lesser trochanter, or there is any possibility of pathological fracture, full length femur views are essential to plan surgery. Where there is a high index of suspicion of fracture, but plain radiographs are inconclusive, gold standard investigation is MRI. However, if unavailable within 24 hours, or if the patient will not tolerate MRI, CT is appropriate. The majority of fractures can be seen with modern CT techniques, and so this is becoming first line in many hospitals. Classification There has been a move away from named classification systems towards descriptive classification systems. Two main types of NOF exist: Intra-capsular, and extra-capsular. Extra-capsular fractures are further divided into pertrochanteric or subtrochanteric (within 5cm distal to the lesser trochanter). All fractures are then described as undisplaced, minimally displaced, or displaced. Femoral neck and head blood supply disruption is common with intracapsular NOF fractures, and rare with extracapsular fractures. This fundamental principle underpins the practise of arthroplasty for intracapsular fractures, and fixation for extracapsular fractures. If you wish to use a named classification system, the most commonly used are below: Elderly intracapsular - Garden Classification Young intrasapsular - Pauvels Classification Intertrochanteric - Evans Subtrochanteric - Russell Taylor Treatment In general, NOF fractures are treated operatively except if the patient is deemed unlikely to survive an anaesthetic. Best Practice Tarif (BPT) dictates that surgery should happen within 36 hours, as delay of greater than 48 hours is associated with increased morbidity and mortality. * The priority with the young patient is to retain the femoral head if possible, even with a displaced intracapsular fracture. The risk of avascular necrosis and non-union (and therefore revision surgery) associated with internal fixation needs weighing up against the sequelae of total hip replacement in the young (wear, dislocation, revision). Discussion is necessary with the patient, on a case by case basis. ** Undisplaced fractures in the elderly can be treated with internal fixation, often with cannulated screws. This is appropriate for valgus impacted subcapital fractures which are inherently stable, to prevent secondary displacement. This does still carry the risk of AVN or non-union, and therefore a future revision. For this reason, many surgeons advocate arthroplasty as a single surgery. *** NICE guidance - patients who fulfil these criteria should be offered total hip replacement which conveys better function and prosthetic survivorship, compared with hemiarthroplasty, but at an increased risk of dislocation. * Intertrochanteric fractures vary greatly in their stability. If the trochanter (and therefore lateral wall), and medial calcar is in tact, then the fracture configuration bears stability. This can be treated with a DHS, as collapse of the fracture is predictable. Where either or both structures are involved in the fracture, stability becomes compromised and many surgeons will favour using an intramedullary device. This is an ongoing debate, and difficult to test in an exam setting.

Answer 212

In those patients who present with a suspected hip fracture, but normal plain films, the most accurate investigation is an MRI or CT scan. Neck of femur (NOF) fracture is a common orthopaedic presentation, with over 65000 fractures in the UK per year. Like many orthopaedic injuries, there is a bimodal age distribution. It is imperative to distinguish between the high energy injury in a young patient, and the low energy osteoporotic fracture in the elderly, as their management aims are very different: Young patient - Usually high energy trauma (e.g road traffic accident, horse riding) and needs treating in accordance with Advanced Trauma Life Support (ATLS) principles. Will often have associated injuries. Aim is to retain the patients own anatomy, and optimise their function. Elderly patient - Predominantly female, fall from standing height (fragility fracture). Often patients have multiple comorbidities that will ultimately dictate their prognosis. Aim of orthopaedic treatment is to immediately regain patient mobility so that morbidity (infection, thromboembolic events, pressure sores etc) and mortality associated with prolonged bed rest is avoided. Left untreated, a neck of femur fracture can be considered a terminal event. Historically, mortality associated with elderly hip fracture is 10% at one month, and 30% at one year. However, this has been improved in the UK with the introduction of multidisciplinary, orthogeriatric lead care and the National Hip Fracture Database and Best Practice Tariff. Pertinent anatomy Osteology - normal neck-shaft angle is 130 +/- 7 degrees, and 10 +/- 7 degrees of neck anteversion. Vascular supply - The predominant blood supply to the femoral head and neck is from the medial and lateral femoral circumflex arteries (branches of profunda femoris). These anastomose and pierce the joint capsule at the base of the neck, mainly posteriorly. There is a small vascular contribution from the artery of the ligament teres. Understanding the blood supply is fundamental to the decision making process in treating NOF fractures. Presentation and initial management Typically, patients present with pain in the hip/groin, a shortened, abducted, externally rotated leg (due to the unopposed pull of the muscles that act across the hip joint) and the inability to straight-leg-raise. With undisplaced fractures, signs are more subtle. High energy injuries should be treated in line with ATLS principles. All patients should be fluid resuscitated, have adequate pain relief (often with a fascio-iliiaca nerve block), and be optimised for surgery. In addition, elderly patients should be assessed by an orthogeriatrician. Imaging Anteroposterior and cross-table lateral plain radiographs are sufficient to diagnose the majority of NOF fractures. If the fracture extends below the level of the lesser trochanter, or there is any possibility of pathological fracture, full length femur views are essential to plan surgery. Where there is a high index of suspicion of fracture, but plain radiographs are inconclusive, gold standard investigation is MRI. However, if unavailable within 24 hours, or if the patient will not tolerate MRI, CT is appropriate. The majority of fractures can be seen with modern CT techniques, and so this is becoming first line in many hospitals. Classification There has been a move away from named classification systems towards descriptive classification systems. Two main types of NOF exist: Intra-capsular, and extra-capsular. Extra-capsular fractures are further divided into pertrochanteric or subtrochanteric (within 5cm distal to the lesser trochanter). All fractures are then described as undisplaced, minimally displaced, or displaced. Femoral neck and head blood supply disruption is common with intracapsular NOF fractures, and rare with extracapsular fractures. This fundamental principle underpins the practise of arthroplasty for intracapsular fractures, and fixation for extracapsular fractures. If you wish to use a named classification system, the most commonly used are below: Elderly intracapsular - Garden Classification Young intrasapsular - Pauvels Classification Intertrochanteric - Evans Subtrochanteric - Russell Taylor Treatment In general, NOF fractures are treated operatively except if the patient is deemed unlikely to survive an anaesthetic. Best Practice Tarif (BPT) dictates that surgery should happen within 36 hours, as delay of greater than 48 hours is associated with increased morbidity and mortality. * The priority with the young patient is to retain the femoral head if possible, even with a displaced intracapsular fracture. The risk of avascular necrosis and non-union (and therefore revision surgery) associated with internal fixation needs weighing up against the sequelae of total hip replacement in the young (wear, dislocation, revision). Discussion is necessary with the patient, on a case by case basis. ** Undisplaced fractures in the elderly can be treated with internal fixation, often with cannulated screws. This is appropriate for valgus impacted subcapital fractures which are inherently stable, to prevent secondary displacement. This does still carry the risk of AVN or non-union, and therefore a future revision. For this reason, many surgeons advocate arthroplasty as a single surgery. *** NICE guidance - patients who fulfil these criteria should be offered total hip replacement which conveys better function and prosthetic survivorship, compared with hemiarthroplasty, but at an increased risk of dislocation. * Intertrochanteric fractures vary greatly in their stability. If the trochanter (and therefore lateral wall), and medial calcar is in tact, then the fracture configuration bears stability. This can be treated with a DHS, as collapse of the fracture is predictable. Where either or both structures are involved in the fracture, stability becomes compromised and many surgeons will favour using an intramedullary device. This is an ongoing debate, and difficult to test in an exam setting.

Answer 213

The subclavian artery passes anterior to the middle scalene. Scalene muscles The 3 paired muscles are: Scalenus anterior: Elevate 1st rib and laterally flex the neck to same side Scalenus medius: Same action as scalenus anterior Scalenus posterior: Elevate 2nd rib and tilt neck to opposite side Innervation Spinal nerves C4-6 Origin Transverse processes C2 to C7 Insertion First and second ribs Important relations The brachial plexus and subclavian artery pass between the anterior and middle scalenes through a space called the scalene hiatus/fissure. The subclavian vein and phrenic nerve pass anteriorly to the anterior scalene as it crosses over the first rib. Thoracic outlet syndrome The scalenes are at risk of adhering to the fascia surrounding the brachial plexus or shortening causing compression of the brachial plexus when it passes between the clavicle and 1st rib causing thoracic outlet syndrome.

Answer 214

The IVC passes through the diaphragm at T8. Inferior vena cava Origin L5 Path Left and right common iliac veins merge to form the IVC. Passes right of midline Paired segmental lumbar veins drain into the IVC throughout its length The right gonadal vein empties directly into the cava and the left gonadal vein generally empties into the left renal vein. The next major veins are the renal veins and the hepatic veins Pierces the central tendon of diaphragm at T8 Right atrium Relations Anteriorly Small bowel, first and third part of duodenum, head of pancreas, liver and bile duct, right common iliac artery, right gonadal artery Posteriorly Right renal artery, right psoas, right sympathetic chain, coeliac ganglion ``` Levels Level Vein T8 Hepatic vein, inferior phrenic vein, pierces diaphragm L1 Suprarenal veins, renal vein L2 Gonadal vein L1-5 Lumbar veins L5 Common iliac vein, formation of IVC ```

Answer 215

It's boundaries are extensor pollicis longus, medially (posterior border) and laterally (anterior border) by the tendons of abductor pollicis longus and extensor pollicis brevis. Anatomical snuffbox Posterior border Tendon of extensor pollicis longus Anterior border Tendons of extensor pollicis brevis and abductor pollicis longus Proximal border Styloid process of the radius Distal border Apex of snuffbox triangle Floor Trapezium and scaphoid Content Radial artery

Answer 216

Periosteum is attached to bone by strong collagenous fibers called Sharpey's fibres, which extend to the outer circumferential and interstitial lamellae. It also provides an attachment for muscles and tendons. Periosteum is a membrane that covers the outer surface of all bones, except at the joints of long bones. Endosteum lines the inner surface of all bones. Periosteum consists of dense irregular connective tissue. Periosteum is divided into an outer "fibrous layer" and inner "cambium layer" (or "osteogenic layer"). The fibrous layer contains fibroblasts, while the cambium layer contains progenitor cells that develop into osteoblasts. These osteoblasts are responsible for increasing the width of a long bone and the overall size of the other bone types. After a bone fracture the progenitor cells develop into osteoblasts and chondroblasts, which are essential to the healing process. As opposed to osseous tissue, periosteum has nociceptive nerve endings, making it very sensitive to manipulation. It also provides nourishment by providing the blood supply. Periosteum is attached to bone by strong collagenous fibers called Sharpey's fibres, which extend to the outer circumferential and interstitial lamellae. It also provides an attachment for muscles and tendons. Periosteum that covers the outer surface of the bones of the skull is known as "pericranium" except when in reference to the layers of the scalp.

Answer 217

The spleen is commonly torn by traction injuries in colonic surgery. The other structures are associated with bleeding during colonic surgery but would not manifest themselves as blood in the paracolic gutter prior to incision of the paracolonic peritoneal edge. Left colon Position As the left colon passes inferiorly its posterior aspect becomes extraperitoneal, and the ureter and gonadal vessels are close posterior relations that may become involved in disease processes At a level of L3-4 (variable) the left colon becomes the sigmoid colon and wholly intraperitoneal once again The sigmoid colon is a highly mobile structure and may even lie on the right side of the abdomen It passes towards the midline, the taenia blend and this marks the transition between sigmoid colon and upper rectum Blood supply Inferior mesenteric artery However, the marginal artery (from the right colon) contributes, this contribution becomes clinically significant when the IMA is divided surgically (e.g. During AAA repair)

Answer 218

The facial artery lies between the gland and mandible and is often ligated during excision of the gland. The lingual artery may be encountered but this is usually later in the operative process as Whartons duct is mobilised. The high salivary viscosity of submandibular gland secretions favors stone formation. Most stones are radio-opaque. The marginal mandibular nerve is the most superficial structure. Relations of the submandibular gland Superficial Platysma, deep fascia and mandible Submandibular lymph nodes Facial vein (facial artery near mandible) Marginal mandibular nerve Cervical branch of the facial nerve ``` Deep Facial artery (inferior to the mandible) Mylohyoid muscle Sub mandibular duct Hyoglossus muscle Lingual nerve Submandibular ganglion Hypoglossal nerve ``` Submandibular duct (Wharton's duct) Opens lateral to the lingual frenulum on the anterior floor of mouth. 5 cm length Lingual nerve wraps around Wharton's duct. As the duct passes forwards it crosses medial to the nerve to lie above it and then crosses back, lateral to it, to reach a position below the nerve. Innervation Sympathetic innervation- Derived from superior cervical ganglion Parasympathetic innervation- Submandibular ganglion via lingual nerve Arterial supply Branch of the facial artery. The facial artery passes through the gland to groove its deep surface. It then emerges onto the face by passing between the gland and the mandible. Venous drainage Anterior facial vein (lies deep to the Marginal Mandibular nerve) Lymphatic drainage Deep cervical and jugular chains of nodes

Answer 219

Hypoglossal The hypoglossal nerve supplies motor innervation to all extrinsic and intrinsic muscles of the tongue. The only possible exception to this is palatoglossus (which is jointly innervated by the vagus and accessory nerves. Cranial nerve lesions Olfactory nerve May be injured in basal skull fractures or involved in frontal lobe tumour extension. Loss of olfactory nerve function in relation to major CNS pathology is seldom an isolated event and thus it is poor localiser of CNS pathology. Optic nerve Problems with visual acuity may result from intra ocular disorders. Problems with the blood supply such as amaurosis fugax may produce temporary visual distortion. More important surgically is the pupillary response to light. The pupillary size may be altered in a number of disorders. Nerves involved in the resizing of the pupil connect to the pretectal nucleus of the high midbrain, bypassing the lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurones pass to the Edinger - Westphal nucleus, motor axons from here pass along with the oculomotor nerve. They synapse with ciliary ganglion neurones; the parasympathetic axons from this then innervate the iris and produce miosis. The miotic pupil is seen in disorders such as Horner's syndrome or opiate overdose. Mydriasis is the dilatation of the pupil in response to disease, trauma, drugs (or the dark!). It is pathological when light fails to induce miosis. The radial muscle is innervated by the sympathetic nervous system. Because the parasympathetic fibres travel with the oculomotor nerve they will be damaged by lesions affecting this nerve (e.g. cranial trauma). The response to light shone in one eye is usually a constriction of both pupils. This indicates intact direct and consensual light reflexes. When the optic nerve has an afferent defect the light shining on the affected eye will produce a diminished pupillary response in both eyes. Whereas light shone on the unaffected eye will produce a normal pupillary response in both eyes. This is referred to as the Marcus Gunn pupil and is seen in conditions such as optic neuritis. In a total CN II lesion shining the light in the affected eye will produce no response. Oculomotor nerve The pupillary effects are described above. In addition it supplies all ocular muscles apart from lateral rectus and superior oblique. Thus the affected eye will be deviated inferolaterally. Levator palpebrae superioris may also be impaired resulting in impaired ability to open the eye. Trochlear nerve The eye will not be able to look down. Trigeminal nerve Largest cranial nerve. Exits the brainstem at the pons. Branches are ophthalmic, maxillary and mandibular. Only the mandibular branch has both sensory and motor fibres. Branches converge to form the trigeminal ganglion (located in Meckels cave). It supplies the muscles of mastication and also tensor veli palatine, mylohyoid, anterior belly of digastric and tensor tympani. The detailed descriptions of the various sensory functions are described in other areas of the website. The corneal reflex is important and is elicited by applying a small tip of cotton wool to the cornea, a reflex blink should occur if it is intact. It is mediated by: the naso ciliary branch of the ophthalmic branch of the trigeminal (sensory component) and the facial nerve producing the motor response. Lesions of the afferent arc will produce bilateral absent blink and lesions of the efferent arc will result in a unilateral absent blink. Abducens nerve The affected eye will have a deficit of abduction. This cranial nerve exits the brainstem between the pons and medulla. It thus has a relatively long intra cranial course which renders it susceptible to damage in raised intra cranial pressure. Facial nerve Emerges from brainstem between pons and medulla. It controls muscles of facial expression and taste from the anterior 2/3 of the tongue. The nerve passes into the petrous temporal bone and into the internal auditory meatus. It then passes through the facial canal and exits at the stylomastoid foramen. It passes through the parotid gland and divides at this point. It does not innervate the parotid gland. Its divisions are considered in other parts of the website. Its motor fibres innervate orbicularis oculi to produce the efferent arm of the corneal reflex. In surgical practice it may be injured during parotid gland surgery or invaded by malignancies of the gland and a lower motor neurone on the ipsilateral side will result. Vestibulo-cochlear nerve Exits from the pons and then passes through the internal auditory meatus. It is implicated in sensorineural hearing loss. Individuals with sensorineural hearing loss will localise the sound in webers test to the normal ear. Rinnes test will be reduced on the affected side but should still work. These two tests will distinguish sensorineural hearing loss from conductive deafness. In the latter condition webers test will localise to the affected ear and Rinnes test will be impaired on the affected side. Surgical lesions affecting this nerve include CNS tumours and basal skull fractures. It may also be damaged by the administration of ototoxic drugs (of which gentamicin is the most commonly used in surgical practice). Glossopharyngeal nerve Exits the pons just above the vagus. Receives sensory fibres from posterior 1/3 tongue, tonsils, pharynx and middle ear (otalgia may occur following tonsillectomy). It receives visceral afferents from the carotid bodies. It supplies parasympathetic fibres to the parotid gland via the otic ganglion and motor function to stylopharyngeaus muscle. The sensory function of the nerve is tested using the gag reflex. Vagus nerve Leaves the medulla between the olivary nucleus and the inferior cerebellar peduncle. Passes through the jugular foramen and into the carotid sheath. Details of the functions of the vagus nerve are covered in the website under relevant organ sub headings. Accessory nerve Exists from the caudal aspect of the brainstem (multiple branches) supplies trapezius and sternocleidomastoid muscles. The distal portion of this nerve is most prone to injury during surgical procedures. Hypoglossal nerve Emerges from the medulla at the preolivary sulcus, passes through the hypoglossal canal. It lies on the carotid sheath and passes deep to the posterior belly of digastric to supply muscles of the tongue (except palatoglossus). Its location near the carotid sheath makes it vulnerable during carotid endarterectomy surgery and damage will produce ipsilateral defect in muscle function.

Answer 220

Trigeminal Taste to the anterior two thirds of the tongue is supplied by the facial nerve, the trigeminal supplies general sensation, this is mediated by the mandibular branch of the trigeminal nerve (via the lingual nerve). Cranial nerve lesions Olfactory nerve May be injured in basal skull fractures or involved in frontal lobe tumour extension. Loss of olfactory nerve function in relation to major CNS pathology is seldom an isolated event and thus it is poor localiser of CNS pathology. Optic nerve Problems with visual acuity may result from intra ocular disorders. Problems with the blood supply such as amaurosis fugax may produce temporary visual distortion. More important surgically is the pupillary response to light. The pupillary size may be altered in a number of disorders. Nerves involved in the resizing of the pupil connect to the pretectal nucleus of the high midbrain, bypassing the lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurones pass to the Edinger - Westphal nucleus, motor axons from here pass along with the oculomotor nerve. They synapse with ciliary ganglion neurones; the parasympathetic axons from this then innervate the iris and produce miosis. The miotic pupil is seen in disorders such as Horner's syndrome or opiate overdose. Mydriasis is the dilatation of the pupil in response to disease, trauma, drugs (or the dark!). It is pathological when light fails to induce miosis. The radial muscle is innervated by the sympathetic nervous system. Because the parasympathetic fibres travel with the oculomotor nerve they will be damaged by lesions affecting this nerve (e.g. cranial trauma). The response to light shone in one eye is usually a constriction of both pupils. This indicates intact direct and consensual light reflexes. When the optic nerve has an afferent defect the light shining on the affected eye will produce a diminished pupillary response in both eyes. Whereas light shone on the unaffected eye will produce a normal pupillary response in both eyes. This is referred to as the Marcus Gunn pupil and is seen in conditions such as optic neuritis. In a total CN II lesion shining the light in the affected eye will produce no response. Oculomotor nerve The pupillary effects are described above. In addition it supplies all ocular muscles apart from lateral rectus and superior oblique. Thus the affected eye will be deviated inferolaterally. Levator palpebrae superioris may also be impaired resulting in impaired ability to open the eye. Trochlear nerve The eye will not be able to look down. Trigeminal nerve Largest cranial nerve. Exits the brainstem at the pons. Branches are ophthalmic, maxillary and mandibular. Only the mandibular branch has both sensory and motor fibres. Branches converge to form the trigeminal ganglion (located in Meckels cave). It supplies the muscles of mastication and also tensor veli palatine, mylohyoid, anterior belly of digastric and tensor tympani. The detailed descriptions of the various sensory functions are described in other areas of the website. The corneal reflex is important and is elicited by applying a small tip of cotton wool to the cornea, a reflex blink should occur if it is intact. It is mediated by: the naso ciliary branch of the ophthalmic branch of the trigeminal (sensory component) and the facial nerve producing the motor response. Lesions of the afferent arc will produce bilateral absent blink and lesions of the efferent arc will result in a unilateral absent blink. Abducens nerve The affected eye will have a deficit of abduction. This cranial nerve exits the brainstem between the pons and medulla. It thus has a relatively long intra cranial course which renders it susceptible to damage in raised intra cranial pressure. Facial nerve Emerges from brainstem between pons and medulla. It controls muscles of facial expression and taste from the anterior 2/3 of the tongue. The nerve passes into the petrous temporal bone and into the internal auditory meatus. It then passes through the facial canal and exits at the stylomastoid foramen. It passes through the parotid gland and divides at this point. It does not innervate the parotid gland. Its divisions are considered in other parts of the website. Its motor fibres innervate orbicularis oculi to produce the efferent arm of the corneal reflex. In surgical practice it may be injured during parotid gland surgery or invaded by malignancies of the gland and a lower motor neurone on the ipsilateral side will result. Vestibulo-cochlear nerve Exits from the pons and then passes through the internal auditory meatus. It is implicated in sensorineural hearing loss. Individuals with sensorineural hearing loss will localise the sound in webers test to the normal ear. Rinnes test will be reduced on the affected side but should still work. These two tests will distinguish sensorineural hearing loss from conductive deafness. In the latter condition webers test will localise to the affected ear and Rinnes test will be impaired on the affected side. Surgical lesions affecting this nerve include CNS tumours and basal skull fractures. It may also be damaged by the administration of ototoxic drugs (of which gentamicin is the most commonly used in surgical practice). Glossopharyngeal nerve Exits the pons just above the vagus. Receives sensory fibres from posterior 1/3 tongue, tonsils, pharynx and middle ear (otalgia may occur following tonsillectomy). It receives visceral afferents from the carotid bodies. It supplies parasympathetic fibres to the parotid gland via the otic ganglion and motor function to stylopharyngeaus muscle. The sensory function of the nerve is tested using the gag reflex. Vagus nerve Leaves the medulla between the olivary nucleus and the inferior cerebellar peduncle. Passes through the jugular foramen and into the carotid sheath. Details of the functions of the vagus nerve are covered in the website under relevant organ sub headings. Accessory nerve Exists from the caudal aspect of the brainstem (multiple branches) supplies trapezius and sternocleidomastoid muscles. The distal portion of this nerve is most prone to injury during surgical procedures. Hypoglossal nerve Emerges from the medulla at the preolivary sulcus, passes through the hypoglossal canal. It lies on the carotid sheath and passes deep to the posterior belly of digastric to supply muscles of the tongue (except palatoglossus). Its location near the carotid sheath makes it vulnerable during carotid endarterectomy surgery and damage will produce ipsilateral defect in muscle function.

Answer 221

Glossopharyngeal The glossopharyngeal nerve supplies general sensation to the posterior third of the tongue and contributes to the gag reflex. Cranial nerve lesions Olfactory nerve May be injured in basal skull fractures or involved in frontal lobe tumour extension. Loss of olfactory nerve function in relation to major CNS pathology is seldom an isolated event and thus it is poor localiser of CNS pathology. Optic nerve Problems with visual acuity may result from intra ocular disorders. Problems with the blood supply such as amaurosis fugax may produce temporary visual distortion. More important surgically is the pupillary response to light. The pupillary size may be altered in a number of disorders. Nerves involved in the resizing of the pupil connect to the pretectal nucleus of the high midbrain, bypassing the lateral geniculate nucleus and the primary visual cortex. From the pretectal nucleus neurones pass to the Edinger - Westphal nucleus, motor axons from here pass along with the oculomotor nerve. They synapse with ciliary ganglion neurones; the parasympathetic axons from this then innervate the iris and produce miosis. The miotic pupil is seen in disorders such as Horner's syndrome or opiate overdose. Mydriasis is the dilatation of the pupil in response to disease, trauma, drugs (or the dark!). It is pathological when light fails to induce miosis. The radial muscle is innervated by the sympathetic nervous system. Because the parasympathetic fibres travel with the oculomotor nerve they will be damaged by lesions affecting this nerve (e.g. cranial trauma). The response to light shone in one eye is usually a constriction of both pupils. This indicates intact direct and consensual light reflexes. When the optic nerve has an afferent defect the light shining on the affected eye will produce a diminished pupillary response in both eyes. Whereas light shone on the unaffected eye will produce a normal pupillary response in both eyes. This is referred to as the Marcus Gunn pupil and is seen in conditions such as optic neuritis. In a total CN II lesion shining the light in the affected eye will produce no response. Oculomotor nerve The pupillary effects are described above. In addition it supplies all ocular muscles apart from lateral rectus and superior oblique. Thus the affected eye will be deviated inferolaterally. Levator palpebrae superioris may also be impaired resulting in impaired ability to open the eye. Trochlear nerve The eye will not be able to look down. Trigeminal nerve Largest cranial nerve. Exits the brainstem at the pons. Branches are ophthalmic, maxillary and mandibular. Only the mandibular branch has both sensory and motor fibres. Branches converge to form the trigeminal ganglion (located in Meckels cave). It supplies the muscles of mastication and also tensor veli palatine, mylohyoid, anterior belly of digastric and tensor tympani. The detailed descriptions of the various sensory functions are described in other areas of the website. The corneal reflex is important and is elicited by applying a small tip of cotton wool to the cornea, a reflex blink should occur if it is intact. It is mediated by: the naso ciliary branch of the ophthalmic branch of the trigeminal (sensory component) and the facial nerve producing the motor response. Lesions of the afferent arc will produce bilateral absent blink and lesions of the efferent arc will result in a unilateral absent blink. Abducens nerve The affected eye will have a deficit of abduction. This cranial nerve exits the brainstem between the pons and medulla. It thus has a relatively long intra cranial course which renders it susceptible to damage in raised intra cranial pressure. Facial nerve Emerges from brainstem between pons and medulla. It controls muscles of facial expression and taste from the anterior 2/3 of the tongue. The nerve passes into the petrous temporal bone and into the internal auditory meatus. It then passes through the facial canal and exits at the stylomastoid foramen. It passes through the parotid gland and divides at this point. It does not innervate the parotid gland. Its divisions are considered in other parts of the website. Its motor fibres innervate orbicularis oculi to produce the efferent arm of the corneal reflex. In surgical practice it may be injured during parotid gland surgery or invaded by malignancies of the gland and a lower motor neurone on the ipsilateral side will result. Vestibulo-cochlear nerve Exits from the pons and then passes through the internal auditory meatus. It is implicated in sensorineural hearing loss. Individuals with sensorineural hearing loss will localise the sound in webers test to the normal ear. Rinnes test will be reduced on the affected side but should still work. These two tests will distinguish sensorineural hearing loss from conductive deafness. In the latter condition webers test will localise to the affected ear and Rinnes test will be impaired on the affected side. Surgical lesions affecting this nerve include CNS tumours and basal skull fractures. It may also be damaged by the administration of ototoxic drugs (of which gentamicin is the most commonly used in surgical practice). Glossopharyngeal nerve Exits the pons just above the vagus. Receives sensory fibres from posterior 1/3 tongue, tonsils, pharynx and middle ear (otalgia may occur following tonsillectomy). It receives visceral afferents from the carotid bodies. It supplies parasympathetic fibres to the parotid gland via the otic ganglion and motor function to stylopharyngeaus muscle. The sensory function of the nerve is tested using the gag reflex. Vagus nerve Leaves the medulla between the olivary nucleus and the inferior cerebellar peduncle. Passes through the jugular foramen and into the carotid sheath. Details of the functions of the vagus nerve are covered in the website under relevant organ sub headings. Accessory nerve Exists from the caudal aspect of the brainstem (multiple branches) supplies trapezius and sternocleidomastoid muscles. The distal portion of this nerve is most prone to injury during surgical procedures. Hypoglossal nerve Emerges from the medulla at the preolivary sulcus, passes through the hypoglossal canal. It lies on the carotid sheath and passes deep to the posterior belly of digastric to supply muscles of the tongue (except palatoglossus). Its location near the carotid sheath makes it vulnerable during carotid endarterectomy surgery and damage will produce ipsilateral defect in muscle function.

Answer 222

Gluteus medius Trendelenburg test Injury or division of the superior gluteal nerve results in a motor deficit that consists of weakened abduction of the thigh by gluteus medius, a disabling gluteus medius limp and a compensatory list of the body to the weakened gluteal side. The compensation results in a gravitational shift so that the body is supported on the unaffected limb. When a person is asked to stand on one leg, the gluteus medius usually contracts as soon as the contralateral leg leaves the floor, preventing the pelvis from dipping towards the unsupported side. When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis on the unsupported side descends, indicating that the gluteus medius on the affected side is weak or non functional ( a positive Trendelenburg test). This eponymous test also refers to a vascular investigation in which tourniquets are placed around the upper thigh, these can help determine whether saphenofemoral incompetence is present.

Answer 223

Femoral access catheters are typically inserted in the region of the femoral triangle. Therefore the physician may encounter the femoral, vein, nerve, branches of the femoral artery and tributaries of the femoral vein. The deep circumflex iliac artery arises above the inguinal ligament and is therefore less likely to be encountered than the superficial circumflex iliac artery which arises below the inguinal ligament. Femoral triangle anatomy ``` Boundaries Superiorly Inguinal ligament Laterally Sartorius Medially Adductor longus Floor Iliopsoas, adductor longus and pectineus Roof Fascia lata and Superficial fascia Superficial inguinal lymph nodes (palpable below the inguinal ligament) Long saphenous vein ``` Contents Femoral vein (medial to lateral) Femoral artery-pulse palpated at the mid inguinal point Femoral nerve Deep and superficial inguinal lymph nodes Lateral cutaneous nerve Great saphenous vein Femoral branch of the genitofemoral nerve

Answer 224

The ureter is the most posterior structure at the hilum of the right kidney and would therefore be encountered first during a posterior approach. Renal arteries The right renal artery is longer than the left renal artery The renal vein/artery/pelvis enter the kidney at the hilum Relations Right Anterior- IVC, right renal vein, the head of the pancreas, and the descending part of the duodenum Left Anterior- left renal vein, the tail of the pancreas Branches The renal arteries are direct branches off the aorta (upper border of L2- right side and L1 - left side) In 30% there may be accessory arteries (mainly left side). Instead of entering the kidney at the hilum, they usually pierce the upper or lower part of the organ. Before reaching the hilum of the kidney, each artery divides into four or five segmental branches (renal vein anterior and ureter posterior); which then divide within the sinus into lobar arteries supplying each pyramid and cortex. Each vessel gives off some small inferior suprarenal branches to the suprarenal gland, the ureter, and the surrounding cellular tissue and muscles.

Answer 225

The median nerve innervates all the short muscles of the thumb except the adductor and the deep head of the short flexor. Palmaris and the interossei are innervated by the ulnar nerve. ``` Palmaris brevis - Ulnar nerve Palmar interossei- Ulnar nerve Adductor pollicis - Ulnar nerve Abductor pollicis longus - Posterior interosseous nerve Abductor pollicis brevis - Median nerve ``` The median nerve is formed by the union of a lateral and medial root respectively from the lateral (C5,6,7) and medial (C8 and T1) cords of the brachial plexus; the medial root passes anterior to the third part of the axillary artery. The nerve descends lateral to the brachial artery, crosses to its medial side (usually passing anterior to the artery). It passes deep to the bicipital aponeurosis and the median cubital vein at the elbow. It passes between the two heads of the pronator teres muscle, and runs on the deep surface of flexor digitorum superficialis (within its fascial sheath). Near the wrist it becomes superficial between the tendons of flexor digitorum superficialis and flexor carpi radialis, deep to palmaris longus tendon. It passes deep to the flexor retinaculum to enter the palm, but lies anterior to the long flexor tendons within the carpal tunnel. ``` Branches Region Branch Upper arm No branches, although the nerve commonly communicates with the musculocutaneous nerve Forearm Pronator teres Flexor carpi radialis Palmaris longus Flexor digitorum superficialis Flexor pollicis longus Flexor digitorum profundus (only the radial half) Distal forearm Palmar cutaneous branch Hand (Motor) Motor supply (LOAF) Lateral 2 lumbricals Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis Hand (Sensory) Over thumb and lateral 2 ½ fingers On the palmar aspect this projects proximally, on the dorsal aspect only the distal regions are innervated with the radial nerve providing the more proximal cutaneous innervation. ``` Patterns of damage Damage at wrist e.g. carpal tunnel syndrome paralysis and wasting of thenar eminence muscles and opponens pollicis (ape hand deformity) sensory loss to palmar aspect of lateral (radial) 2 ½ fingers Damage at elbow, as above plus: unable to pronate forearm weak wrist flexion ulnar deviation of wrist Anterior interosseous nerve (branch of median nerve) leaves just below the elbow results in loss of pronation of forearm and weakness of long flexors of thumb and index finger

Answer 226

The middle meningeal artery is the most likely source of the extradural haematoma in this setting. It is a branch of the maxillary artery. The middle cerebral artery does not give rise to the middle meningeal artery. Note that the question is asking for the vessel which gives rise to the middle meningeal artery ("the likely culprit vessel is a branch of which of the following") Middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater (the outermost meninges) . The middle meningeal artery is the largest of the three (paired) arteries which supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an extra dural hematoma. In the dry cranium, the middle meningeal, which runs within the dura mater surrounding the brain, makes a deep indention in the calvarium. The middle meningeal artery is intimately associated with the auriculotemporal nerve which wraps around the artery making the two easily identifiable in the dissection of human cadavers and also easily damaged in surgery.

Answer 227

The left main bronchus lies at T6. Topographical anatomy of the thorax is important as it helps surgeons to predict the likely structures to be injured in trauma scenarios (so popular with examiners) The right lung is composed of 3 lobes divided by the oblique and transverse fissures. The left lung has two lobes divided by the oblique fissure.The apex of both lungs is approximately 4cm superior to the sterno-costal joint of the first rib. Immediately below this is a sulcus created by the subclavian artery. Peripheral contact points of the lung Base: diaphragm Costal surface: corresponds to the cavity of the chest Mediastinal surface: Contacts the mediastinal pleura. Has the cardiac impression. Above and behind this concavity is a triangular depression named the hilum, where the structures which form the root of the lung enter and leave the viscus. These structures are invested by pleura, which, below the hilum and behind the pericardial impression, forms the pulmonary ligament Right lung Above the hilum is the azygos vein; Superior to this is the groove for the superior vena cava and right innominate vein; behind this, and nearer the apex, is a furrow for the innominate artery. Behind the hilum and the attachment of the pulmonary ligament is a vertical groove for the oesophagus; In front and to the right of the lower part of the oesophageal groove is a deep concavity for the extrapericardiac portion of the inferior vena cava. The root of the right lung lies behind the superior vena cava and the right atrium, and below the azygos vein. The right main bronchus is shorter, wider and more vertical than the left main bronchus and therefore the route taken by most foreign bodies. Left lung Above the hilum is the furrow produced by the aortic arch, and then superiorly the groove accommodating the left subclavian artery; Behind the hilum and pulmonary ligament is a vertical groove produced by the descending aorta, and in front of this, near the base of the lung, is the lower part of the oesophagus. The root of the left lung passes under the aortic arch and in front of the descending aorta. ``` Inferior borders of both lungs 6th rib in mid clavicular line 8th rib in mid axillary line 10th rib posteriorly The pleura runs two ribs lower than the corresponding lung level. ```

Answer 228

Spongiose part Bucks fascia is a layer of deep fascia that covers the penis it is continuous with the external spermatic fascia and the penile suspensory ligament. The membranous part of the urethra may partially pass through Bucks fascia as it passes into the penis. However, the spongiose part of the urethra is contained wholly within Bucks fascia. Female urethra The female urethra is shorter and more acutely angulated than the male urethra. It is an extra-peritoneal structure and embedded in the endopelvic fascia. The neck of the bladder is subjected to transmitted intra-abdominal pressure and therefore deficiency in this area may result in stress urinary incontinence. Between the layers of the urogenital diaphragm the female urethra is surrounded by the external urethral sphincter, this is innervated by the pudendal nerve. It ultimately lies anterior to the vaginal orifice. Male urethra In males the urethra is much longer and is divided into four parts. Pre-prostatic urethra Extremely short and lies between the bladder and prostate gland.It has a stellate lumen and is between 1 and 1.5cm long.Innervated by sympathetic noradrenergic fibres, as this region is composed of striated muscles bundles they may contract and prevent retrograde ejaculation. Prostatic urethra This segment is wider than the membranous urethra and contains several openings for the transmission of semen (at the midpoint of the urethral crest). Membranous urethra Narrowest part of the urethra and surrounded by external sphincter. It traverses the perineal membrane 2.5cm postero-inferior to the symphysis pubis. Penile urethra Travels through the corpus spongiosum on the underside of the penis. It is the longest urethral segment.It is dilated at its origin as the infrabulbar fossa and again in the gland penis as the navicular fossa. The bulbo-urethral glands open into the spongiose section of the urethra 2.5cm below the perineal membrane. The urothelium is transitional in nature near to the bladder and becomes squamous more distally.

Answer 229

The posterior aspect is intrasynovial and the knee itself comprises the largest synovial joint in the body. It may swell considerably following trauma such as ACL injury. Which may be extremely painful owing to rich innervation from femoral, sciatic and ( a smaller) contribution from the obturator nerve. During full extension all ligaments are taut and the knee is locked. The knee joint is a synovial joint, the largest and most complicated. It consists of two condylar joints between the femur and tibia and a sellar joint between the patella and the femur. The tibiofemoral articular surfaces are incongruent, however, this is improved by the presence of the menisci. The degree of congruence is related to the anatomical position of the knee joint and is greatest in full extension. Knee joint compartments Tibiofemoral Comprised of the patella/femur joint, lateral and medial compartments (between femur condyles and tibia) Synovial membrane and cruciate ligaments partially separate the medial and lateral compartments Patellofemoral Ligamentum patellae Actions: provides joint stability in full extension Fibrous capsule The capsule of the knee joint is a complex, composite structure with contributions from adjacent tendons. Anterior fibres The capsule does not pass proximal to the patella. It blends with the tendinous expansions of vastus medialis and lateralis Posterior fibres These fibres are vertical and run from the posterior surface of the femoral condyles to the posterior aspect of the tibial condyle Medial fibres Attach to the femoral and tibial condyles beyond their articular margins, blending with the tibial collateral ligament Lateral fibres Attach to the femur superior to popliteus, pass over its tendon to head of fibula and tibial condyle Bursae Anterior Subcutaneous prepatellar bursa; between patella and skin Deep infrapatellar bursa; between tibia and patellar ligament Subcutaneous infrapatellar bursa; between distal tibial tuberosity and skin Laterally Bursa between lateral head of gastrocnemius and joint capsule Bursa between fibular collateral ligament and tendon of biceps femoris Bursa between fibular collateral ligament and tendon of popliteus Medially Bursa between medial head of gastrocnemius and the fibrous capsule Bursa between tibial collateral ligament and tendons of sartorius, gracilis and semitendinosus Bursa between the tendon of semimembranosus and medial tibial condyle and medial head of gastrocnemius Posterior Highly variable and inconsistent Ligaments Medial collateral ligament Medial epicondyle femur to medial tibial condyle: valgus stability Lateral collateral ligament Lateral epicondyle femur to fibula head: varus stability Anterior cruciate ligament Anterior tibia to lateral intercondylar notch femur: prevents tibia sliding anteriorly Posterior cruciate ligament Posterior tibia to medial intercondylar notch femur: prevents tibia sliding posteriorly Patellar ligament Central band of the tendon of quadriceps femoris, extends from patella to tibial tuberosity Menisci Medial and lateral menisci compensate for the incongruence of the femoral and tibial condyles. Composed of fibrous tissue. Medial meniscus is attached to the tibial collateral ligament. Lateral meniscus is attached to the loose fibres at the lateral edge of the joint and is separate from the fibular collateral ligament. The lateral meniscus is crossed by the popliteus tendon. Nerve supply The knee joint is supplied by the femoral, tibial and common peroneal divisions of the sciatic and by a branch from the obturator nerve. Hip pathology pain may be referred to the knee. Blood supply Genicular branches of the femoral artery, popliteal and anterior tibial arteries all supply the knee joint.

Answer 230

The musculocutaneous nerve lies between the biceps and brachialis muscles. Musculocutaneous nerve Branch of lateral cord of brachial plexus Path It penetrates the coracobrachialis muscle Passes obliquely between the biceps brachii and the brachialis to the lateral side of the arm Above the elbow it pierces the deep fascia lateral to the tendon of the biceps brachii Continues into the forearm as the lateral cutaneous nerve of the forearm Innervates Coracobrachialis Biceps brachii Brachialis

Answer 231

The superior adrenal artery is a branch of the inferior phrenic artery. Adrenal gland anatomy Anatomy Location Superomedially to the upper pole of each kidney Relationships of the right adrenal Diaphragm-Posteriorly, Kidney-Inferiorly, Vena Cava-Medially, Hepato-renal pouch and bare area of the liver-Anteriorly Relationships of the left adrenal Crus of the diaphragm-Postero- medially, Pancreas and splenic vessels-Inferiorly, Lesser sac and stomach-Anteriorly Arterial supply Superior adrenal arteries- from inferior phrenic artery, Middle adrenal arteries - from aorta, Inferior adrenal arteries -from renal arteries Venous drainage of the right adrenal Via one central vein directly into the IVC Venous drainage of the left adrenal Via one central vein into the left renal vein

Answer 232

The obturator nerve exits through the obturator foramen. Greater sciatic foramen ``` Contents Nerves Sciatic Nerve Superior and Inferior Gluteal Nerves Pudendal Nerve Posterior Femoral Cutaneous Nerve Nerve to Quadratus Femoris Nerve to Obturator internus Vessels Superior Gluteal Artery and vein Inferior Gluteal Artery and vein Internal Pudendal Artery and vein ``` Piriformis The piriformis is a landmark for identifying structures passing out of the sciatic notch Above piriformis: Superior gluteal vessels Below piriformis: Inferior gluteal vessels, sciatic nerve (10% pass through it, <1% above it), posterior cutaneous nerve of the thigh Greater sciatic foramen boundaries Anterolaterally Greater sciatic notch of the ilium Posteromedially Sacrotuberous ligament Inferior Sacrospinous ligament and the ischial spine Superior Anterior sacroiliac ligament Structures passing between both foramina (Medial to lateral) Pudendal nerve Internal pudendal artery Nerve to obturator internus ``` Contents of the lesser sciatic foramen Tendon of the obturator internus Pudendal nerve Internal pudendal artery and vein Nerve to the obturator internus ```

Answer 233

Foramen spinosum- Sphenoid bone ``` Foramen ovale Sphenoid bone Otic ganglion V3 (Mandibular nerve:3rd branch of trigeminal) Accessory meningeal artery Lesser petrosal nerve Emissary veins ``` Foramen spinosum Sphenoid bone Middle meningeal artery Meningeal branch of the Mandibular nerve Foramen rotundum Sphenoid bone Maxillary nerve (V2) Foramen lacerum/ carotid canal Sphenoid bone Base of the medial pterygoid plate. Internal carotid artery* Nerve and artery of the pterygoid canal Jugular foramen Temporal bone Anterior: inferior petrosal sinus Intermediate: glossopharyngeal, vagus, and accessory nerves. Posterior: sigmoid sinus (becoming the internal jugular vein) and some meningeal branches from the occipital and ascending pharyngeal arteries. Foramen magnum Occipital bone Anterior and posterior spinal arteries Vertebral arteries Medulla oblongata Stylomastoid foramen Temporal bone Stylomastoid artery Facial nerve Superior orbital fissure Sphenoid bone Oculomotor nerve (III) Recurrent meningeal artery Trochlear nerve (IV) Lacrimal, frontal and nasociliary branches of ophthalmic nerve (V1) Abducent nerve (VI) Superior ophthalmic vein *= In life the foramen lacerum is occluded by a cartilagenous plug. The ICA initially passes into the carotid canal which ascends superomedially to enter the cranial cavity through the foramen lacerum.

Answer 234

The vessel damaged is the epigastric artery. This originates from the external iliac artery The inferior epigastric artery arises from the external iliac artery immediately above the inguinal ligament. It then passes along the medial margin of the deep inguinal ring. From here it continues superiorly to lie behind the rectus abdominis muscle.

Answer 235

The left renal vein runs across the surface of the aorta and may require deliberate ligation during juxtarenal aneurysm repair. ``` Abdominal aortic topography Origin T12 Termination L4 Posterior relations L1-L4 Vertebral bodies Anterior relations Lesser omentum Liver Left renal vein Inferior mesenteric vein Third part of duodenum Pancreas Parietal peritoneum Peritoneal cavity Right lateral relations Right crus of the diaphragm Cisterna chyli Azygos vein IVC (becomes posterior distally) Left lateral relations 4th part of duodenum Duodenal-jejunal flexure Left sympathetic trunk ```

Answer 236

Mnemonic branches off the posterior cord S ubscapular (upper and lower) T horacodorsal A xillary R adial The musculocutaneous nerve is a branch off the lateral cord. Brachial plexus Origin Anterior rami of C5 to T1 Sections of the plexus Roots, trunks, divisions, cords, branches Mnemonic:Real Teenagers Drink Cold Beer Roots Located in the posterior triangle Pass between scalenus anterior and medius Trunks Located posterior to middle third of clavicle Upper and middle trunks related superiorly to the subclavian artery Lower trunk passes over 1st rib posterior to the subclavian artery Divisions Apex of axilla Cords Related to axillary artery

Answer 237

Immediate reduction and application of backslab This is an unstable ankle injury that is likely to require surgical fixation. The immediate management of a displaced ankle fracture is to reduce the fracture to prevent soft tissues compromise and help reduce swelling. This can be performed before an x-ray is obtained if performing the x-ray will significantly delay reduction. Ankle injuries An ankle fracture relates to a fracture around the tibio-talar joint. It generally refers to a fracture involving the lateral, and/or medial and/or posterior malleolus. Pilon and Tillaux fractures are also considered to be ankle fractures, but are not covered here. Ankle fractures are common. They effect men and women in equal numbers, but men have a higher rate as young adults (sports and contact injuries), and women a higher rate post-menopausal (fragility type fracture). ``` Osseous anatomy The ankle (or mortise) joint consists of the distal tibia (tibial plafond and posterior malleolus), the distal fibula (lateral malleolus), and the talus. The main movement at the ankle joint is plantar and dorsiflexion. ``` Ligamentous anatomy Medial side: Deltoid ligament. This is divided into superficial and deep portions. It is the primary restraint to valgus tilting of the talus. Lateral side: Lateral ligament complex consisting from anterior to posterior of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). Together they resist valgus stress to the ankle, and are a restraint to anterior translation of the talus within the mortise joint. Syndesmosis: The syndesmosis is a ligament complex between the distal tibia and fibula, holding the two bones together. It is fundamental to the integrity of the ankle joint, and its disruption leads to instability. It consists of (from anterior to posterior) the anterior-inferior tibiofibular ligament (AITFL), the transverse tibiofibular ligament (TTFL), the interosseous membrane, and the posterior-inferior tibiofibular ligament (PITFL). Presentation and initial management Patients will present following a traumatic event with a painful, swollen ankle, and reluctance/inability to weight bear. The Ottawa rules can be applied to differentiate between an ankle fracture and sprain, but can be unreliable. In high energy injuries, management should follow ATLS principles to identify more significant injuries first. Neurovascular status of the foot should be documented, and open injuries should be excluded. If an open injury is identified, it should be managed in line with BOAST 4 principles1. If an obvious deformity exists, it should be reduced as soon as possible with appropriate analgesia or conscious sedation. Radiographs of clearly deformed or dislocated joints are not necessary, and removing the pressure on the surrounding soft tissues from the underlying bony deformity is the priority. If the fracture pattern is not clinically obvious then plain radiographs are appropriate and will guide the subsequent manipulation during plaster-of-paris below knee backslab application. Imaging AP, lateral and mortise views (20o internal rotation) are essential to evaluate fracture displacement and syndesmotic injury. Decreased tibiofibular overlap, medial joint clear space and lateral talar shift all indicate a syndesmotic injury. (In subtle cases of shift, imaging the uninjured ankle can be helpful as a proportion of the population have little or no tibiotalar overlap 2.) Where there is suspicion of syndesmosis involvement in the absence of radiographic evidence, stress radiographs can be diagnostic. Complex fracture patterns (and increasingly posterior malleolar fractures) are best defined using CT. Classification The most commonly used classifications are Lauge-Hansen and Danis-Weber. Lauge-Hansen Comprises two parts: first part is the foot position, and the second part is the force applied. Useful for understanding the forces involved and therefore predict the ligamentous or bony injury. Results in four injury patterns: Supination - Adduction (SA) - 10-20% Supination - External rotation (SER) - 40-75% Pronation - Abduction (PA) - 5-20% Pronation - External rotation (PER) - 5-20% Not often used in clinical practice but good for understanding the principles of ankle fracture. Danis-Weber Commonly used. Based on the level of the fibula fracture in relation to the syndesmosis. The more proximal, the greater the risk of syndesmotic injury and therefore fracture instability. A - fracture below the level of the syndesmosis B - fracture at the level of the syndesmosis / level of the tibial plafond C - fracture above the level of the syndesmosis. This includes Maisonneuve fractures (proximal fibula fracture), which can be associated with ankle instability. Beware the high fibula fracture - it may be an ankle fracture! The Weber classification is based purely on the the lateral side. All injuries can include a medial or posterior bony or ligamentous injury which also dictates fracture stability (bimalleolar and trimalleolar fractures are more unstable). Treatment When deciding upon treatment for an ankle fracture, one must consider both the fracture and the patient. Diabetic patients and smokers are at greater risk of post-operative complication, especially wound problems and infection. Likewise, the long term outcome of post-traumatic arthritis from a malunited ankle fracture is extremely important for a young patient, but not as relevant in the elderly. Therefore, normal surgical decision processes apply as with all fractures. Defining stability of an ankle fracture underpins the treatment decision. Weber A - Unimalleolar Weber A Weber fractures by definition are stable and therefore can be mobilised fully weight bearing in an ankle boot. Weber C - Fractures tend to include syndesmotic disruption and are usually bimalleolar (either bony or ligamentous). They are therefore unstable and usually require operative fixation. In addition to the fracture fixation, the syndesmosis usually requires reconstruction/augmentation with screws to restore the joint integrity and function. Weber B - B fractures vary greatly. They can be part of a trimalleolar injury and therefore extremely unstable, requiring fixation. Alternatively, a uni-malleolar Weber B fracture can be a stable injury, and therefore mobilised immediately in an ankle boot. Defining the stability can be challenging, and often involves stress radiographs, or a trial of mobilisation and repeat radiographs. Defining stability is the subject of much ongoing research. However, treating undisplaced ankle fractures in a below knee plaster, non-weight bearing for six weeks is still widely practised, and a safe approach. When operative fixation is appropriate, it is usually via open reduction and internal fixation using plates and screws. It must be carried out when soft tissue swelling has settled in order to minimise the risk of wound problems. This can often take a week to settle. The use of fibula nails is expanding, but is not yet mainstream. Ankle fractures can also be treated with external fixation, or with a hind foot nail in patients who need fixation but where soft tissue or bone quality is poor. Post operative management Ankle fractures generally take 6 weeks to unite enough to prevent secondary displacement. This is therefore an appropriate time period to keep a cast on in a conservatively managed patient. Weight bearing post-operatively depends on the quality of the fixation and bone quality, and preference varies between surgeons, ranging from aggressive early mobilisation to a period of non-weight bearing. Return to activities takes approximately three months, and often requires assistance of a physiotherapist to improve range-of-movement and muscle strengthening.

Answer 238

Surgical fixation This is a Maisonneuve fracture of the proximal fibula. It indicates an unstable ankle injury with likely injury to the interosseous membrane. In the setting of radiographic evidence of syndesmotic widening, this requires surgical fixation to reduce and stabilise the syndesmosis. Ankle injuries An ankle fracture relates to a fracture around the tibio-talar joint. It generally refers to a fracture involving the lateral, and/or medial and/or posterior malleolus. Pilon and Tillaux fractures are also considered to be ankle fractures, but are not covered here. Ankle fractures are common. They effect men and women in equal numbers, but men have a higher rate as young adults (sports and contact injuries), and women a higher rate post-menopausal (fragility type fracture). ``` Osseous anatomy The ankle (or mortise) joint consists of the distal tibia (tibial plafond and posterior malleolus), the distal fibula (lateral malleolus), and the talus. The main movement at the ankle joint is plantar and dorsiflexion. ``` Ligamentous anatomy Medial side: Deltoid ligament. This is divided into superficial and deep portions. It is the primary restraint to valgus tilting of the talus. Lateral side: Lateral ligament complex consisting from anterior to posterior of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). Together they resist valgus stress to the ankle, and are a restraint to anterior translation of the talus within the mortise joint. Syndesmosis: The syndesmosis is a ligament complex between the distal tibia and fibula, holding the two bones together. It is fundamental to the integrity of the ankle joint, and its disruption leads to instability. It consists of (from anterior to posterior) the anterior-inferior tibiofibular ligament (AITFL), the transverse tibiofibular ligament (TTFL), the interosseous membrane, and the posterior-inferior tibiofibular ligament (PITFL). Presentation and initial management Patients will present following a traumatic event with a painful, swollen ankle, and reluctance/inability to weight bear. The Ottawa rules can be applied to differentiate between an ankle fracture and sprain, but can be unreliable. In high energy injuries, management should follow ATLS principles to identify more significant injuries first. Neurovascular status of the foot should be documented, and open injuries should be excluded. If an open injury is identified, it should be managed in line with BOAST 4 principles1. If an obvious deformity exists, it should be reduced as soon as possible with appropriate analgesia or conscious sedation. Radiographs of clearly deformed or dislocated joints are not necessary, and removing the pressure on the surrounding soft tissues from the underlying bony deformity is the priority. If the fracture pattern is not clinically obvious then plain radiographs are appropriate and will guide the subsequent manipulation during plaster-of-paris below knee backslab application. Imaging AP, lateral and mortise views (20o internal rotation) are essential to evaluate fracture displacement and syndesmotic injury. Decreased tibiofibular overlap, medial joint clear space and lateral talar shift all indicate a syndesmotic injury. (In subtle cases of shift, imaging the uninjured ankle can be helpful as a proportion of the population have little or no tibiotalar overlap 2.) Where there is suspicion of syndesmosis involvement in the absence of radiographic evidence, stress radiographs can be diagnostic. Complex fracture patterns (and increasingly posterior malleolar fractures) are best defined using CT. Classification The most commonly used classifications are Lauge-Hansen and Danis-Weber. Lauge-Hansen Comprises two parts: first part is the foot position, and the second part is the force applied. Useful for understanding the forces involved and therefore predict the ligamentous or bony injury. Results in four injury patterns: Supination - Adduction (SA) - 10-20% Supination - External rotation (SER) - 40-75% Pronation - Abduction (PA) - 5-20% Pronation - External rotation (PER) - 5-20% Not often used in clinical practice but good for understanding the principles of ankle fracture. Danis-Weber Commonly used. Based on the level of the fibula fracture in relation to the syndesmosis. The more proximal, the greater the risk of syndesmotic injury and therefore fracture instability. A - fracture below the level of the syndesmosis B - fracture at the level of the syndesmosis / level of the tibial plafond C - fracture above the level of the syndesmosis. This includes Maisonneuve fractures (proximal fibula fracture), which can be associated with ankle instability. Beware the high fibula fracture - it may be an ankle fracture! The Weber classification is based purely on the the lateral side. All injuries can include a medial or posterior bony or ligamentous injury which also dictates fracture stability (bimalleolar and trimalleolar fractures are more unstable). Treatment When deciding upon treatment for an ankle fracture, one must consider both the fracture and the patient. Diabetic patients and smokers are at greater risk of post-operative complication, especially wound problems and infection. Likewise, the long term outcome of post-traumatic arthritis from a malunited ankle fracture is extremely important for a young patient, but not as relevant in the elderly. Therefore, normal surgical decision processes apply as with all fractures. Defining stability of an ankle fracture underpins the treatment decision. Weber A - Unimalleolar Weber A Weber fractures by definition are stable and therefore can be mobilised fully weight bearing in an ankle boot. Weber C - Fractures tend to include syndesmotic disruption and are usually bimalleolar (either bony or ligamentous). They are therefore unstable and usually require operative fixation. In addition to the fracture fixation, the syndesmosis usually requires reconstruction/augmentation with screws to restore the joint integrity and function. Weber B - B fractures vary greatly. They can be part of a trimalleolar injury and therefore extremely unstable, requiring fixation. Alternatively, a uni-malleolar Weber B fracture can be a stable injury, and therefore mobilised immediately in an ankle boot. Defining the stability can be challenging, and often involves stress radiographs, or a trial of mobilisation and repeat radiographs. Defining stability is the subject of much ongoing research. However, treating undisplaced ankle fractures in a below knee plaster, non-weight bearing for six weeks is still widely practised, and a safe approach. When operative fixation is appropriate, it is usually via open reduction and internal fixation using plates and screws. It must be carried out when soft tissue swelling has settled in order to minimise the risk of wound problems. This can often take a week to settle. The use of fibula nails is expanding, but is not yet mainstream. Ankle fractures can also be treated with external fixation, or with a hind foot nail in patients who need fixation but where soft tissue or bone quality is poor. Post operative management Ankle fractures generally take 6 weeks to unite enough to prevent secondary displacement. This is therefore an appropriate time period to keep a cast on in a conservatively managed patient. Weight bearing post-operatively depends on the quality of the fixation and bone quality, and preference varies between surgeons, ranging from aggressive early mobilisation to a period of non-weight bearing. Return to activities takes approximately three months, and often requires assistance of a physiotherapist to improve range-of-movement and muscle strengthening.

Answer 239

Application of external fixation device This is a pilon fracture, which a high energy injury of the distal tibia. The patient will ultimately require surgical fixation but early management involves applying a spanning external fixator to temporarily reduce the fracture and allow soft tissue swelling to settle. A CT scan should then be performed to aid surgical planning. Ankle injuries An ankle fracture relates to a fracture around the tibio-talar joint. It generally refers to a fracture involving the lateral, and/or medial and/or posterior malleolus. Pilon and Tillaux fractures are also considered to be ankle fractures, but are not covered here. Ankle fractures are common. They effect men and women in equal numbers, but men have a higher rate as young adults (sports and contact injuries), and women a higher rate post-menopausal (fragility type fracture). ``` Osseous anatomy The ankle (or mortise) joint consists of the distal tibia (tibial plafond and posterior malleolus), the distal fibula (lateral malleolus), and the talus. The main movement at the ankle joint is plantar and dorsiflexion. ``` Ligamentous anatomy Medial side: Deltoid ligament. This is divided into superficial and deep portions. It is the primary restraint to valgus tilting of the talus. Lateral side: Lateral ligament complex consisting from anterior to posterior of the anterior talofibular ligament (ATFL), calcaneofibular ligament (CFL), and the posterior talofibular ligament (PTFL). Together they resist valgus stress to the ankle, and are a restraint to anterior translation of the talus within the mortise joint. Syndesmosis: The syndesmosis is a ligament complex between the distal tibia and fibula, holding the two bones together. It is fundamental to the integrity of the ankle joint, and its disruption leads to instability. It consists of (from anterior to posterior) the anterior-inferior tibiofibular ligament (AITFL), the transverse tibiofibular ligament (TTFL), the interosseous membrane, and the posterior-inferior tibiofibular ligament (PITFL). Presentation and initial management Patients will present following a traumatic event with a painful, swollen ankle, and reluctance/inability to weight bear. The Ottawa rules can be applied to differentiate between an ankle fracture and sprain, but can be unreliable. In high energy injuries, management should follow ATLS principles to identify more significant injuries first. Neurovascular status of the foot should be documented, and open injuries should be excluded. If an open injury is identified, it should be managed in line with BOAST 4 principles1. If an obvious deformity exists, it should be reduced as soon as possible with appropriate analgesia or conscious sedation. Radiographs of clearly deformed or dislocated joints are not necessary, and removing the pressure on the surrounding soft tissues from the underlying bony deformity is the priority. If the fracture pattern is not clinically obvious then plain radiographs are appropriate and will guide the subsequent manipulation during plaster-of-paris below knee backslab application. Imaging AP, lateral and mortise views (20o internal rotation) are essential to evaluate fracture displacement and syndesmotic injury. Decreased tibiofibular overlap, medial joint clear space and lateral talar shift all indicate a syndesmotic injury. (In subtle cases of shift, imaging the uninjured ankle can be helpful as a proportion of the population have little or no tibiotalar overlap 2.) Where there is suspicion of syndesmosis involvement in the absence of radiographic evidence, stress radiographs can be diagnostic. Complex fracture patterns (and increasingly posterior malleolar fractures) are best defined using CT. Classification The most commonly used classifications are Lauge-Hansen and Danis-Weber. Lauge-Hansen Comprises two parts: first part is the foot position, and the second part is the force applied. Useful for understanding the forces involved and therefore predict the ligamentous or bony injury. Results in four injury patterns: Supination - Adduction (SA) - 10-20% Supination - External rotation (SER) - 40-75% Pronation - Abduction (PA) - 5-20% Pronation - External rotation (PER) - 5-20% Not often used in clinical practice but good for understanding the principles of ankle fracture. Danis-Weber Commonly used. Based on the level of the fibula fracture in relation to the syndesmosis. The more proximal, the greater the risk of syndesmotic injury and therefore fracture instability. A - fracture below the level of the syndesmosis B - fracture at the level of the syndesmosis / level of the tibial plafond C - fracture above the level of the syndesmosis. This includes Maisonneuve fractures (proximal fibula fracture), which can be associated with ankle instability. Beware the high fibula fracture - it may be an ankle fracture! The Weber classification is based purely on the the lateral side. All injuries can include a medial or posterior bony or ligamentous injury which also dictates fracture stability (bimalleolar and trimalleolar fractures are more unstable). Treatment When deciding upon treatment for an ankle fracture, one must consider both the fracture and the patient. Diabetic patients and smokers are at greater risk of post-operative complication, especially wound problems and infection. Likewise, the long term outcome of post-traumatic arthritis from a malunited ankle fracture is extremely important for a young patient, but not as relevant in the elderly. Therefore, normal surgical decision processes apply as with all fractures. Defining stability of an ankle fracture underpins the treatment decision. Weber A - Unimalleolar Weber A Weber fractures by definition are stable and therefore can be mobilised fully weight bearing in an ankle boot. Weber C - Fractures tend to include syndesmotic disruption and are usually bimalleolar (either bony or ligamentous). They are therefore unstable and usually require operative fixation. In addition to the fracture fixation, the syndesmosis usually requires reconstruction/augmentation with screws to restore the joint integrity and function. Weber B - B fractures vary greatly. They can be part of a trimalleolar injury and therefore extremely unstable, requiring fixation. Alternatively, a uni-malleolar Weber B fracture can be a stable injury, and therefore mobilised immediately in an ankle boot. Defining the stability can be challenging, and often involves stress radiographs, or a trial of mobilisation and repeat radiographs. Defining stability is the subject of much ongoing research. However, treating undisplaced ankle fractures in a below knee plaster, non-weight bearing for six weeks is still widely practised, and a safe approach. When operative fixation is appropriate, it is usually via open reduction and internal fixation using plates and screws. It must be carried out when soft tissue swelling has settled in order to minimise the risk of wound problems. This can often take a week to settle. The use of fibula nails is expanding, but is not yet mainstream. Ankle fractures can also be treated with external fixation, or with a hind foot nail in patients who need fixation but where soft tissue or bone quality is poor. Post operative management Ankle fractures generally take 6 weeks to unite enough to prevent secondary displacement. This is therefore an appropriate time period to keep a cast on in a conservatively managed patient. Weight bearing post-operatively depends on the quality of the fixation and bone quality, and preference varies between surgeons, ranging from aggressive early mobilisation to a period of non-weight bearing. Return to activities takes approximately three months, and often requires assistance of a physiotherapist to improve range-of-movement and muscle strengthening.

Answer 240

Boundaries of the deep inguinal ring: Superolaterally - transversalis fascia Inferomedially - inferior epigastric artery The deep inguinal ring is closely related to the inferior epigastric artery. The inferior epigastric artery forms part of the structure referred to as Hesselbach's triangle. Inguinal canal Location Above the inguinal ligament The inguinal canal is 4cm long The superficial ring is located anterior to the pubic tubercle The deep ring is located approximately 1.5-2cm above the half way point between the anterior superior iliac spine and the pubic tubercle ``` Boundaries of the inguinal canal Floor External oblique aponeurosis Inguinal ligament Lacunar ligament Roof Internal oblique Transversus abdominis Anterior wall External oblique aponeurosis Posterior wall Transversalis fascia Conjoint tendon Laterally Internal ring Transversalis fascia Fibres of internal oblique Medially External ring Conjoint tendon ``` Contents Males Spermatic cord and ilioinguinal nerve As it passes through the canal the spermatic cord has 3 coverings: External spermatic fascia from external oblique aponeurosis Cremasteric fascia Internal spermatic fascia Females Round ligament of uterus and ilioinguinal nerve

Answer 241

Submental nodes The lymphatic drainage of the anterior two thirds of the tongue shows only minimal communication of lymphatics across the midline, so metastasis to the ipsilateral nodes is usual. The lymphatic drainage of the posterior third of the tongue have communicating networks, as a result early bilateral nodal metastases are more common in this area. Lymphatics from the tip of the tongue usually pass to the sub mental nodes and from there to the deep cervical nodes. Lymphatics from the mid portion of the tongue usually drain to the submandibular nodes and then to the deep cervical nodes. Mid tongue tumours that are laterally located will usually drain to the ipsilateral deep cervical nodes, those from more central regions may have bilateral deep cervical nodal involvement.

Answer 242

At the lower border of the femoral triangle the femoral artery passes under the sartorius muscle. This can be retracted to improve access. Femoral triangle anatomy ``` Boundaries Superiorly Inguinal ligament Laterally Sartorius Medially Adductor longus Floor Iliopsoas, adductor longus and pectineus Roof Fascia lata and Superficial fascia Superficial inguinal lymph nodes (palpable below the inguinal ligament) Long saphenous vein ``` Contents Femoral vein (medial to lateral) Femoral artery-pulse palpated at the mid inguinal point Femoral nerve Deep and superficial inguinal lymph nodes Lateral cutaneous nerve Great saphenous vein Femoral branch of the genitofemoral nerve

Answer 243

The main purpose of this question is to differentiate the features of an UMN lesion and a LMN lesion. The features of a LMN lesion include: Flaccid paralysis of muscles supplied Atrophy of muscles supplied. Loss of reflexes of muscles supplied. Muscles fasciculation For lesions below L1 LMN signs will occur. Hence in an L3 lesion, there will be loss of the patella reflex but there will be no extensor plantar reflex. Spinal cord Located in a canal within the vertebral column that affords it structural support. Rostrally it continues to the medulla oblongata of the brain and caudally it tapers at a level corresponding to the L1-2 interspace (in the adult), a central structure, the filum terminale anchors the cord to the first coccygeal vertebra. The spinal cord is characterised by cervico-lumbar enlargements and these, broadly speaking, are the sites which correspond to the brachial and lumbar plexuses respectively. There are some key points to note when considering the surgical anatomy of the spinal cord: * During foetal growth the spinal cord becomes shorter than the spinal canal, hence the adult site of cord termination at the L1-2 level. * Due to growth of the vertebral column the spine segmental levels may not always correspond to bony landmarks as they do in the cervical spine. * The spinal cord is incompletely divided into two symmetrical halves by a dorsal median sulcus and ventral median fissure. Grey matter surrounds a central canal that is continuous rostrally with the ventricular system of the CNS. * The grey matter is sub divided cytoarchitecturally into Rexeds laminae. * Afferent fibres entering through the dorsal roots usually terminate near their point of entry but may travel for varying distances in Lissauers tract. In this way they may establish synaptic connections over several levels * At the tip of the dorsal horn are afferents associated with nociceptive stimuli. The ventral horn contains neurones that innervate skeletal muscle. The key point to remember when revising CNS anatomy is to keep a clinical perspective in mind. So it is worth classifying the ways in which the spinal cord may become injured. These include: Trauma either direct or as a result of disc protrusion Neoplasia either by direct invasion (rare) or as a result of pathological vertebral fracture Inflammatory diseases such as Rheumatoid disease, or OA (formation of osteophytes compressing nerve roots etc. Vascular either as a result of stroke (rare in cord) or as complication of aortic dissection Infection historically diseases such as TB, epidural abscesses. The anatomy of the cord will, to an extent dictate the clinical presentation. Some points/ conditions to remember: Brown- Sequard syndrome-Hemisection of the cord producing ipsilateral loss of proprioception and upper motor neurone signs, plus contralateral loss of pain and temperature sensation. The explanation of this is that the fibres decussate at different levels. Lesions below L1 will tend to present with lower motor neurone signs

Answer 244

The posterior cord gives rise to: Radial nerve ((innervates the triceps, brachioradialis, wrist extensors, and finger extensors) Axillary nerve (innervates deltoid and teres minor) Upper subscapular nerve (innervates subscapularis) Lower subscapular nerve (innervates teres major and subscapularis) Thoracodorsal nerve (innervates latissimus dorsi) This is a description of a posterior cord lesion. Remember that the posterior cord gives rise to the axillary and radial nerve. Cords of the brachial plexus The brachial plexus cords are described according to their relationship with the axillary artery. The cords pass over the 1st rib near to the dome of the lung and pass beneath the clavicle immediately posterior to the subclavian artery. Lateral cord Anterior divisions of the upper and middle trunks form the lateral cord Origin of the lateral pectoral nerve (C5, C6, C7) Medial cord Anterior division of the lower trunk forms the medial cord Origin of the medial pectoral nerve (C8, T1), the medial brachial cutaneous nerve (T1), and the medial antebrachial cutaneous nerve (C8, T1) Posterior cord Formed by the posterior divisions of the 3 trunks (C5-T1) Origin of the upper and lower subscapular nerves (C7, C8 and C5, C6, respectively) and the thoracodorsal nerve to the latissimus dorsi (also known as the middle subscapular nerve, C6, C7, C8), axillary and radial nerve

Answer 245

Lateral compartment The interosseous membrane separates the anterior and posterior compartments. The deep and superficial compartments are separated by the deep transverse fascia. The peroneus brevis is part of the lateral compartment. Compartments of the thigh ``` Formed by septae passing from the femur to the fascia lata: Anterior compartment Femoral Iliacus Tensor fasciae latae Sartorius Quadriceps femoris Femoral artery ``` ``` Medial compartment Obturator Adductor longus/magnus/brevis Gracilis Obturator externus Profunda femoris artery and obturator artery ``` ``` Posterior compartment (2 layers) Sciatic Semimembranosus Semitendinosus Biceps femoris Branches of Profunda femoris artery ``` Compartments of the lower leg Separated by the interosseous membrane (anterior and posterior compartments), anterior fascial septum (separate anterior and lateral compartments) and posterior fascial septum (separate lateral and posterior compartments): ``` Anterior compartment Deep peroneal nerve Tibialis anterior Extensor digitorum longus Extensor hallucis longus Peroneus tertius Anterior tibial artery ``` Posterior compartment Tibial Muscles: deep and superficial compartments (separated by deep transverse fascia) Deep: Flexor hallucis longus, Flexor digitalis longus, Tibialis posterior, Popliteus Superficial: Gastrocnemius, Soleus, Plantaris Posterior tibial Lateral compartment Superficial peroneal Peroneus longus/brevis Peroneal artery

Answer 246

Tibialis posterior As an artery of the anterior compartment, the anterior tibial artery is closely related to tibialis anterior. The tibialis posterior is related to it at its origin. Anterior tibial artery Begins opposite the distal border of popliteus Terminates in front of the ankle, continuing as the dorsalis pedis artery As it descends it lies on the interosseous membrane, distal part of the tibia and front of the ankle joint Passes between the tendons of extensor digitorum and extensor hallucis longus distally It is related to the deep peroneal nerve, it lies anterior to the middle third of the vessel and lateral to it in the lower third

Answer 247

Pectineus is not a lateral rotator. Pectineus adducts and medially rotates the femur. Mnemonic lateral hip rotators: P-GO-GO-Q (top to bottom) ``` Piriformis Gemellus superior Obturator internus Gemellus inferior Obturator externus Quadratus femoris ``` Hip joint Head of femur articulates with acetabulum of the pelvis Both covered by articular hyaline cartilage The acetabulum forms at the union of the ilium, pubis, and ischium The triradiate cartilage (Y-shaped growth plate) separates the pelvic bones The acetabulum holds the femoral head by the acetabular labrum Normal angle between femoral head and femoral shaft is 130o Ligaments Transverse ligament: joints anterior and posterior ends of the articular cartilage Head of femur ligament (ligamentum teres): acetabular notch to the fovea. Contains arterial supply to head of femur in children. Extracapsular ligaments Iliofemoral ligament: inverted Y shape. Anterior iliac spine to the trochanteric line Pubofemoral ligament: acetabulum to lesser trochanter Ischiofemoral ligament: posterior support. Ischium to greater trochanter. Blood supply Medial circumflex femoral and lateral circumflex femoral arteries (Branches of profunda femoris). Also from the inferior gluteal artery. These form an anastomosis and travel to up the femoral neck to supply the head.

Answer 248

The IJV does not lie in the posterior triangle. However, the terminal branches of the external jugular vein do. Posterior triangle of the neck Boundaries Apex Sternocleidomastoid and the Trapezius muscles at the Occipital bone Anterior Posterior border of the Sternocleidomastoid Posterior Anterior border of the Trapezius Base Middle third of the clavicle ``` Contents Nerves Accessory nerve Phrenic nerve Three trunks of the brachial plexus Branches of the cervical plexus: Supraclavicular nerve, transverse cervical nerve, great auricular nerve, lesser occipital nerve Vessels External jugular vein Subclavian artery Muscles Inferior belly of omohyoid Scalene Lymph nodes Supraclavicular Occipital ```

Answer 249

Hip x-ray The main differential diagnosis in a boy over 10 years old is of slipped upper femoral epiphysis. Knee pain is a common presenting feature. An anteroposterior pelvic x-ray may miss a minor slip, therefore request a hip film. Developmental dysplasia of the hip Usually diagnosed in infancy by screening tests. May be bilateral, when disease is unilateral there may be leg length inequality. As disease progresses child may limp and then early onset arthritis. More common in extended breech babies. Splints and harnesses or traction. In later years osteotomy and hip realignment procedures may be needed. In arthritis a joint replacement may be needed. However, this is best deferred if possible as it will almost certainly require revision Initially no obvious change on plain films and USS gives best resolution until 3 months of age. On plain films Shentons line should form a smooth arc Perthes Disease Hip pain (may be referred to the knee) usually occurring between 5 and 12 years of age. Bilateral disease in 20%. Remove pressure from joint to allow normal development. Physiotherapy. Usually self-limiting if diagnosed and treated promptly. X-rays will show flattened femoral head. Eventually in untreated cases the femoral head will fragment. Slipped upper femoral epiphysis Typically seen in obese male adolescents. Pain is often referred to the knee. Limitation to internal rotation is usually seen. Knee pain is usually present 2 months prior to hip slipping. Bilateral in 20%. Bed rest and non-weight bearing. Aim to avoid avascular necrosis. If severe slippage or risk of it occurring then percutaneous pinning of the hip may be required. X-rays will show the femoral head displaced and falling inferolaterally (like a melting ice cream cone) The Southwick angle gives indication of disease severity

Answer 250

USS hip This child is at risk of developmental dysplasia of the hip (up to 20% will have DDH), so should have the hip joints scanned to exclude this. Developmental dysplasia of the hip Usually diagnosed in infancy by screening tests. May be bilateral, when disease is unilateral there may be leg length inequality. As disease progresses child may limp and then early onset arthritis. More common in extended breech babies. Splints and harnesses or traction. In later years osteotomy and hip realignment procedures may be needed. In arthritis a joint replacement may be needed. However, this is best deferred if possible as it will almost certainly require revision Initially no obvious change on plain films and USS gives best resolution until 3 months of age. On plain films Shentons line should form a smooth arc Perthes Disease Hip pain (may be referred to the knee) usually occurring between 5 and 12 years of age. Bilateral disease in 20%. Remove pressure from joint to allow normal development. Physiotherapy. Usually self-limiting if diagnosed and treated promptly. X-rays will show flattened femoral head. Eventually in untreated cases the femoral head will fragment. Slipped upper femoral epiphysis Typically seen in obese male adolescents. Pain is often referred to the knee. Limitation to internal rotation is usually seen. Knee pain is usually present 2 months prior to hip slipping. Bilateral in 20%. Bed rest and non-weight bearing. Aim to avoid avascular necrosis. If severe slippage or risk of it occurring then percutaneous pinning of the hip may be required. X-rays will show the femoral head displaced and falling inferolaterally (like a melting ice cream cone) The Southwick angle gives indication of disease severity

Answer 251

MRI Perthes disease should be suspected in boys over 4 years old presenting with a limp. Early disease can be missed on x-ray. An MRI will often demonstrate areas of hypoperfusion and subtle changes that allow for earlier diagnosis. A bone scan is an alternative option. Developmental dysplasia of the hip Usually diagnosed in infancy by screening tests. May be bilateral, when disease is unilateral there may be leg length inequality. As disease progresses child may limp and then early onset arthritis. More common in extended breech babies. Splints and harnesses or traction. In later years osteotomy and hip realignment procedures may be needed. In arthritis a joint replacement may be needed. However, this is best deferred if possible as it will almost certainly require revision Initially no obvious change on plain films and USS gives best resolution until 3 months of age. On plain films Shentons line should form a smooth arc Perthes Disease Hip pain (may be referred to the knee) usually occurring between 5 and 12 years of age. Bilateral disease in 20%. Remove pressure from joint to allow normal development. Physiotherapy. Usually self-limiting if diagnosed and treated promptly. X-rays will show flattened femoral head. Eventually in untreated cases the femoral head will fragment. Slipped upper femoral epiphysis Typically seen in obese male adolescents. Pain is often referred to the knee. Limitation to internal rotation is usually seen. Knee pain is usually present 2 months prior to hip slipping. Bilateral in 20%. Bed rest and non-weight bearing. Aim to avoid avascular necrosis. If severe slippage or risk of it occurring then percutaneous pinning of the hip may be required. X-rays will show the femoral head displaced and falling inferolaterally (like a melting ice cream cone) The Southwick angle gives indication of disease severity

Answer 252

The marginal mandibular nerve lies deep to platysma. It supplies the depressor anguli oris and the depressor labii inferioris. If injured it may lead to facial asymmetry and dribbling. ``` Relations of the submandibular gland Superficial Platysma, deep fascia and mandible Submandibular lymph nodes Facial vein (facial artery near mandible) Marginal mandibular nerve Cervical branch of the facial nerve Deep Facial artery (inferior to the mandible) Mylohyoid muscle Sub mandibular duct Hyoglossus muscle Lingual nerve Submandibular ganglion Hypoglossal nerve ``` Submandibular duct (Wharton's duct) Opens lateral to the lingual frenulum on the anterior floor of mouth. 5 cm length Lingual nerve wraps around Wharton's duct. As the duct passes forwards it crosses medial to the nerve to lie above it and then crosses back, lateral to it, to reach a position below the nerve. Innervation Sympathetic innervation- Derived from superior cervical ganglion Parasympathetic innervation- Submandibular ganglion via lingual nerve Arterial supply Branch of the facial artery. The facial artery passes through the gland to groove its deep surface. It then emerges onto the face by passing between the gland and the mandible. Venous drainage Anterior facial vein (lies deep to the Marginal Mandibular nerve) Lymphatic drainage Deep cervical and jugular chains of nodes

Answer 253

IMA During a high anterior resection of such tumours, the inferior mesenteric artery is ligated. Note that the branches (mainly middle rectal branch) of the internal iliac artery are important in maintaining vascularity of the rectal stump and hence the integrity of the anastomoses. Rectum The rectum is approximately 12 cm long. It is a capacitance organ. It has both intra and extraperitoneal components. The transition between the sigmoid colon is marked by the disappearance of the tenia coli.The extra peritoneal rectum is surrounded by mesorectal fat that also contains lymph nodes. This mesorectal fatty layer is removed surgically during rectal cancer surgery (Total Mesorectal Excision). The fascial layers that surround the rectum are important clinical landmarks, anteriorly lies the fascia of Denonvilliers. Posteriorly lies Waldeyers fascia. Extra peritoneal rectum Posterior upper third Posterior and lateral middle third Whole lower third ``` Relations Anteriorly (Males) Rectovesical pouch Bladder Prostate Seminal vesicles Anteriorly (Females) Recto-uterine pouch (Douglas) Cervix Vaginal wall Posteriorly Sacrum Coccyx Middle sacral artery Laterally Levator ani Coccygeus ``` Arterial supply Superior rectal artery Venous drainage Superior rectal vein Lymphatic drainage Mesorectal lymph nodes (superior to dentate line) Inguinal nodes (inferior to dentate line)

Answer 254

It enters the temporal bone through the internal acoustic meatus and exits through the stylomastoid foramen. The facial nerve is the main nerve supplying the structures of the second embryonic branchial arch. It is predominantly an efferent nerve to the muscles of facial expression, digastric muscle and also to many glandular structures. It contains a few afferent fibres which originate in the cells of its genicular ganglion and are concerned with taste. Supply - 'face, ear, taste, tear' Face: muscles of facial expression Ear: nerve to stapedius Taste: supplies anterior two-thirds of tongue Tear: parasympathetic fibres to lacrimal glands, also salivary glands Path Subarachnoid path Origin: motor- pons, sensory- nervus intermedius Pass through the petrous temporal bone into the internal auditory meatus with the vestibulocochlear nerve. Here they combine to become the facial nerve. Facial canal path The canal passes superior to the vestibule of the inner ear At the medial aspect of the middle ear, it becomes wider and contains the geniculate ganglion. - 3 branches: 1. greater petrosal nerve 2. nerve to stapedius 3. chorda tympani Stylomastoid foramen Passes through the stylomastoid foramen (tympanic cavity anterior and mastoid antrum posteriorly) Posterior auricular nerve and branch to posterior belly of digastric and stylohyoid muscle ``` Face Enters parotid gland and divides into 5 branches: Temporal branch Zygomatic branch Buccal branch Marginal mandibular branch Cervical branch ```

Answer 255

Erbs Palsy C5, C6 lesion The features include: Waiter's tip position Loss of shoulder abduction (deltoid and supraspinatus paralysis) Loss of external rotation of the shoulder (paralysis of infraspinatus) Loss of elbow flexion (paralysis of biceps, brachialis and brachioradialis) Loss of forearm supination (paralysis of Biceps) The motorcyclist has had an Erb's palsy (C5, C6 root lesion). This is commonly known to be associated with birth injury when a baby has a shoulder dystocia. Brachial plexus Origin Anterior rami of C5 to T1 Sections of the plexus Roots, trunks, divisions, cords, branches Mnemonic:Real Teenagers Drink Cold Beer Roots Located in the posterior triangle Pass between scalenus anterior and medius Trunks Located posterior to middle third of clavicle Upper and middle trunks related superiorly to the subclavian artery Lower trunk passes over 1st rib posterior to the subclavian artery Divisions Apex of axilla Cords Related to axillary artery

Answer 256

The ileo - colic artery supplies the caecum and would require high ligation during a right hemicolectomy. The middle colic artery should generally be preserved when resecting a caecal lesion. This question is essentially asking you to name the vessel supplying the caecum. The SMA does not directly supply the caecum, it is the ileocolic artery which does this. Caecum ``` Location Proximal right colon below the ileocaecal valve Intraperitoneal Posterior relations Psoas Iliacus Femoral nerve Genitofemoral nerve Gonadal vessels Anterior relations Greater omentum Arterial supply Ileocolic artery Lymphatic drainage Mesenteric nodes accompany the venous drainage ``` The caecum is the most distensible part of the colon and in complete large bowel obstruction with a competent ileocaecal valve the most likely site of eventual perforation.

Answer 257

L3 Prolapsed disc A prolapsed lumbar disc usually produces clear dermatomal leg pain associated with neurological deficits. Features Leg pain usually worse than back Pain often worse when sitting The table below demonstrates the expected features according to the level of compression: L3 nerve root compression Sensory loss over anterior thigh/knee Weak quadriceps Reduced knee reflex Positive femoral stretch test L5 nerve root compression Sensory loss dorsum of foot Weakness in foot and big toe dorsiflexion Reflexes intact Positive sciatic nerve stretch test S1 nerve root compression Sensory loss posterolateral aspect of leg and lateral aspect of foot Weakness in plantar flexion of foot Reduced ankle reflex Positive sciatic nerve stretch test Management Similar to that of other musculoskeletal lower back pain: analgesia, physiotherapy, exercises Persistent symptoms, muscular weakness, bladder or bowel dysfunction are indications for urgent MRI scanning to delineate the disease extent to allow surgical planning Plain spinal x-rays have no useful role in establishing the extent of disk disease

Answer 258

The lumbar arteries are posteriorly sited and are a common cause of back bleeding during aortic surgery. The other vessels cited all exit the aorta in the regions that have been cross clamped.

Answer 259

It inserts into the medial aspect of the upper part of the tibia. Sartorius Longest strap muscle in the body Most superficial muscle in the anterior compartment of the thigh Origin Anterior superior iliac spine Insertion Medial surface of the of the body of the tibia (upper part). It inserts anterior to gracilis and semitendinosus Nerve Supply Femoral nerve (L2,3) Action Flexor of the hip and knee, slight abducts the thigh and rotates it laterally It assists with medial rotation of the tibia on the femur. For example it would play a pivotal role in placing the right heel onto the left knee ( and vice versa) Important relations The middle third of this muscle, and its strong underlying fascia forms the roof of the adductor canal , in which lie the femoral vessels, the saphenous nerve and the nerve to vastus medialis.

Answer 260

The urinary bladder has a rich venous plexus surrounding it, this drains subsequently into the internal iliac vein. The vesicoprostatic plexus may be a site of considerable venous bleeding during cystectomy. Bladder The empty bladder is contained within the pelvic cavity. It is usually a three sided pyramid. The apex of the bladder points forwards towards the symphysis pubis and the base lies immediately anterior to the rectum or vagina. Continuous with the apex is the median umbilical ligament, during development this was the site of the urachus. The inferior aspect of the bladder is retroperitoneal and the superior aspect covered by peritoneum. As the bladder distends it will tend to separate the peritoneum from the fascia of transversalis. For this reason a bladder that is distended due to acute urinary retention may be approached with a suprapubic catheter that avoids entry into the peritoneal cavity. The trigone is the least mobile part of the bladder and forms the site of the ureteric orifices and internal urethral orifice. In the empty bladder the ureteric orifices are approximately 2-3cm apart, this distance may increase to 5cm in the distended bladder. Arterial supply The superior and inferior vesical arteries provide the main blood supply to the bladder. These are branches of the internal iliac artery. Venous drainage In males the bladder is drained by the vesicoprostatic venous plexus. In females the bladder is drained by the vesicouterine venous plexus. In both sexes this venous plexus will ultimately drain to the internal iliac veins. Lymphatic drainage Lymphatic drainage is predominantly to the external iliac nodes, internal iliac and obturator nodes also form sites of bladder lymphatic drainage. Innervation Parasympathetic nerve fibres innervate the bladder from the pelvic splanchnic nerves. Sympathetic nerve fibres are derived from L1 and L2 via the hypogastric nerve plexuses. The parasympathetic nerve fibres will typically cause detrusor muscle contraction and result in voiding. The muscle of the trigone is innervated by the sympathetic nervous system. The external urethral sphincter is under conscious control. During bladder filling the rate of firing of nerve impulses to the detrusor muscle is low and receptive relaxation occurs. At higher volumes and increased intra vesical pressures the rate of neuronal firing will increase and eventually voiding will occur.

Answer 261

Deep ulnar nerve Branches of the ulnar nerve in the wrist and hand At the wrist the ulnar nerve divides into superficial and deep branches. The superficial branch lies deep to the palmaris brevis. It divides into two; to produce digital nerves, which innervate the skin of the medial third of the palm and the palmar surface of one and a half fingers. The deep branch arises from the nerve on the flexor retinaculum lateral to the pisiform bone. It passes posteriorly between the abductor and short flexor of the little finger supplying them, and supplying and piercing the opponens digiti minimi near its origin from the flexor retinaculum, turns laterally over the distal surface of the Hook of the Hamate bone. It eventually passes between the two heads of adductor pollicis with the deep palmar arch and ends in the first dorsal interosseous muscle. In the palm the deep branch also innervates the lumbricals and interosseous muscles.

Answer 262

The superior mesenteric artery arises from the aorta and passes anterior to the lower part of the pancreas. Invasion of this structure is a relative contra indication to resectional surgery. The pancreas is a retroperitoneal organ and lies posterior to the stomach. It may be accessed surgically by dividing the peritoneal reflection that connects the greater omentum to the transverse colon. The pancreatic head sits in the curvature of the duodenum. Its tail lies close to the hilum of the spleen, a site of potential injury during splenectomy. ``` Relations Posterior to the pancreas Pancreatic head Inferior vena cava Common bile duct Right and left renal veins Superior mesenteric vein and artery Pancreatic neck Superior mesenteric vein, portal vein Pancreatic body- Left renal vein Crus of diaphragm Psoas muscle Adrenal gland Kidney Aorta Pancreatic tail Left kidney ``` ``` Anterior to the pancreas Pancreatic head 1st part of the duodenum Pylorus Gastroduodenal artery SMA and SMV(uncinate process) Pancreatic body Stomach Duodenojejunal flexure Pancreatic tail Splenic hilum ``` Superior to the pancreas Coeliac trunk and its branches common hepatic artery and splenic artery Grooves of the head of the pancreas 2nd and 3rd part of the duodenum Arterial supply Head: pancreaticoduodenal artery Rest: splenic artery Venous drainage Head: superior mesenteric vein Body and tail: splenic vein Ampulla of Vater Merge of pancreatic duct and common bile duct Is an important landmark, halfway along the second part of the duodenum, that marks the anatomical transition from foregut to midgut (also the site of transition between regions supplied by coeliac trunk and SMA).

Answer 263

The cephalic vein is a favored vessel for arteriovenous fistula formation and should be preserved in patients with end stage renal failure The cephalic vein penetrates the calvipectoral fascia (but not the pectoralis major) prior to terminating in the axillary vein. Cephalic vein Path Dorsal venous arch drains laterally into the cephalic vein Crosses the anatomical snuffbox and travels laterally up the arm At the antecubital fossa connected to the basilic vein by the median cubital vein Pierces deep fascia of deltopectoral groove to join axillary vein

Answer 264

The outermost covering of the spermatic cord is derived from the external oblique aponeurosis.This layer is added as the cord passes through the superficial inguinal ring. Spermatic cord Formed by the vas deferens and is covered by the following structures: Layer Origin Internal spermatic fascia Transversalis fascia Cremasteric fascia From the fascial coverings of internal oblique External spermatic fascia External oblique aponeurosis Contents of the cord Vas deferens Transmits sperm and accessory gland secretions Testicular artery Branch of abdominal aorta supplies testis and epididymis Artery of vas deferens Arises from inferior vesical artery Cremasteric artery Arises from inferior epigastric artery Pampiniform plexus Venous plexus, drains into right or left testicular vein Sympathetic nerve fibres Lie on arteries, the parasympathetic fibres lie on the vas Genital branch of the genitofemoral nerve Supplies cremaster Lymphatic vessels Drain to lumbar and para-aortic nodes Scrotum Composed of skin and closely attached dartos fascia. Arterial supply from the anterior and posterior scrotal arteries Lymphatic drainage to the inguinal lymph nodes Parietal layer of the tunica vaginalis is the innermost layer Testes The testes are surrounded by the tunica vaginalis (closed peritoneal sac). The parietal layer of the tunica vaginalis adjacent to the internal spermatic fascia. The testicular arteries arise from the aorta immediately inferiorly to the renal arteries. The pampiniform plexus drains into the testicular veins, the left drains into the left renal vein and the right into the inferior vena cava. Lymphatic drainage is to the para-aortic nodes.

Answer 265

Mnemonic for the Carpal Bones Sally Likes To Play The Tiny Chrome Harmonica She Looks Too Pretty Try To Catch Her Scared Lovers Try Positions That They Can't Handle Trapezius is a muscle of the back. No tendons attach to: Scaphoid, lunate, triquetrum (stabilised by ligaments) The wrist is comprised of 8 carpal bones, these are arranged in two rows of 4. It is convex from side to side posteriorly and concave anteriorly.

Answer 266

The middle colic artery supplies the transverse colon and requires high ligation during cancer resections. It is a branch of the superior mesenteric artery. Transverse colon The right colon undergoes a sharp turn at the level of the hepatic flexure to become the transverse colon. At this point it also becomes intraperitoneal. It is connected to the inferior border of the pancreas by the transverse mesocolon. The greater omentum is attached to the superior aspect of the transverse colon from which it can easily be separated. The mesentery contains the middle colic artery and vein. The greater omentum remains attached to the transverse colon up to the splenic flexure. At this point the colon undergoes another sharp turn. Relations Superior Liver and gall-bladder, the greater curvature of the stomach, and the lower end of the spleen Inferior Small intestine Anterior Greater omentum Posterior From right to left with the descending portion of the duodenum, the head of the pancreas, convolutions of the jejunum and ileum, spleen

Answer 267

Femoral triangle: Adductor longus medially Inguinal ligament superiorly Sartorius muscle laterally Adductor longus forms the medial border of the femoral triangle. It is closely related to the long saphenous vein which overlies it and the profunda branch of the femoral artery. The femoral nerve is related to it inferiorly. However, the tendon of iliacus inserts proximally and is not in contact with adductor longs. Adductor longus Origin Anterior body of pubis Insertion Middle third of linea aspera Action Adducts and flexes the thigh, medially rotate the hip Innervation Anterior division of obturator nerve (L2, L3, L4)

Answer 268

The 8th and10th ribs lie more superiorly. The 12th rib is a closer relation posteriorly. Quadratus lumborum runs between the posterior part of the iliac crest, iliolumbar ligament and the transverse processes of the lower lumbar vertebrae to the medial part of the lower border of the last rib and transverse process of the upper lumbar vertebrae. In these last two locations it is posterior to the kidney. Renal anatomy Each kidney is about 11cm long, 5cm wide and 3cm thick. They are located in a deep gutter alongside the projecting vertebral bodies, on the anterior surface of psoas major. In most cases the left kidney lies approximately 1.5cm higher than the right. The upper pole of both kidneys approximates with the 11th rib (beware pneumothorax during nephrectomy). On the left hand side the hilum is located at the L1 vertebral level and the right kidney at level L1-2. The lower border of the kidneys is usually alongside L3. Fascial covering Each kidney and suprarenal gland is enclosed within a common layer of investing fascia, derived from the transversalis fascia. It is divided into anterior and posterior layers (Gerotas fascia). Renal structure Kidneys are surrounded by an outer cortex and an inner medulla which usually contains between 6 and 10 pyramidal structures. The papilla marks the innermost apex of these. They terminate at the renal pelvis, into the ureter. Lying in a hollow within the kidney is the renal sinus. This contains: 1. Branches of the renal artery 2. Tributaries of the renal vein 3. Major and minor calyces's 4. Fat Structures at the renal hilum The renal vein lies most anteriorly, then renal artery (it is an end artery) and the ureter lies most posterior.

Answer 269

The 11th and 12th ribs lie posterior to the kidneys and may be encountered during a posterior approach. A pneumothorax is a recognised complication of this type of surgery. Each kidney is about 11cm long, 5cm wide and 3cm thick. They are located in a deep gutter alongside the projecting vertebral bodies, on the anterior surface of psoas major. In most cases the left kidney lies approximately 1.5cm higher than the right. The upper pole of both kidneys approximates with the 11th rib (beware pneumothorax during nephrectomy). On the left hand side the hilum is located at the L1 vertebral level and the right kidney at level L1-2. The lower border of the kidneys is usually alongside L3. Fascial covering Each kidney and suprarenal gland is enclosed within a common layer of investing fascia, derived from the transversalis fascia. It is divided into anterior and posterior layers (Gerotas fascia). Renal structure Kidneys are surrounded by an outer cortex and an inner medulla which usually contains between 6 and 10 pyramidal structures. The papilla marks the innermost apex of these. They terminate at the renal pelvis, into the ureter. Lying in a hollow within the kidney is the renal sinus. This contains: 1. Branches of the renal artery 2. Tributaries of the renal vein 3. Major and minor calyces's 4. Fat Structures at the renal hilum The renal vein lies most anteriorly, then renal artery (it is an end artery) and the ureter lies most posterior.

Answer 270

The canal exists to allow for the physiological expansion of the femoral vein, which lies lateral to it. The femoral canal lies at the medial aspect of the femoral sheath. The femoral sheath is a fascial tunnel containing both the femoral artery laterally and femoral vein medially. The canal lies medial to the vein. ``` Borders of the femoral canal Laterally Femoral vein Medially Lacunar ligament Anteriorly Inguinal ligament Posteriorly Pectineal ligament ``` Contents Lymphatic vessels Cloquet's lymph node Physiological significance Allows the femoral vein to expand to allow for increased venous return to the lower limbs. Pathological significance As a potential space, it is the site of femoral hernias. The relatively tight neck places these at high risk of strangulation.

Answer 271

Deltoid may abduct the shoulder and is not a rotator cuff muscle. Supraspinatus muscle Suprascapular nerve Infraspinatus muscle Suprascapular nerve Teres minor muscle Axillary nerve Subscapularis muscle Superior and inferior subscapular nerves

Answer 272

Peroneus brevis lies in the lateral compartment. Compartments of the thigh ``` Formed by septae passing from the femur to the fascia lata. Anterior compartment Femoral Iliacus Tensor fasciae latae Sartorius Quadriceps femoris Femoral artery Medial compartment Obturator Adductor longus/magnus/brevis Gracilis Obturator externus Profunda femoris artery and obturator artery Posterior compartment (2 layers) Sciatic Semimembranosus Semitendinosus Biceps femoris Branches of Profunda femoris artery ``` Compartments of the lower leg Separated by the interosseous membrane (anterior and posterior compartments), anterior fascial septum (separate anterior and lateral compartments) and posterior fascial septum (separate lateral and posterior compartments) Anterior compartment Deep peroneal nerve Tibialis anterior Extensor digitorum longus Extensor hallucis longus Peroneus tertius Anterior tibial artery Posterior compartment Tibial Muscles: deep and superficial compartments (separated by deep transverse fascia) Deep: Flexor hallucis longus, Flexor digitalis longus, Tibialis posterior, Popliteus Superficial: Gastrocnemius, Soleus, Plantaris Posterior tibial Lateral compartment Superficial peroneal Peroneus longus/brevis Peroneal artery

Answer 273

There are three unpaired branches to the abdominal viscera. These include the coeliac axis, the SMA and IMA. Branches to the adrenals, renal arteries and gonadal vessels are paired. The fourth unpaired branch of the abdominal aorta, the median sacral artery, does not directly supply the abdominal viscera.

Answer 274

When approaching the submandibular gland the facial vein and submandibular lymph nodes are the most superficially encountered structures. Each sub mandibular gland has a superficial and deep part, separated by the mylohyoid muscle. The facial artery passes in a groove on the superficial aspect of the gland. It then emerges onto the surface of the face by passing between the gland and the mandible. The facial vein is encountered first in this surgical approach because the incision is made 4cm below the mandible (to avoid injury to the marginal mandibular nerve). ``` Relations of the submandibular gland Superficial Platysma, deep fascia and mandible Submandibular lymph nodes Facial vein (facial artery near mandible) Marginal mandibular nerve Cervical branch of the facial nerve Deep Facial artery (inferior to the mandible) Mylohyoid muscle Sub mandibular duct Hyoglossus muscle Lingual nerve Submandibular ganglion Hypoglossal nerve ``` Submandibular duct (Wharton's duct) Opens lateral to the lingual frenulum on the anterior floor of mouth. 5 cm length Lingual nerve wraps around Wharton's duct. As the duct passes forwards it crosses medial to the nerve to lie above it and then crosses back, lateral to it, to reach a position below the nerve. Innervation Sympathetic innervation- Derived from superior cervical ganglion Parasympathetic innervation- Submandibular ganglion via lingual nerve Arterial supply Branch of the facial artery. The facial artery passes through the gland to groove its deep surface. It then emerges onto the face by passing between the gland and the mandible. Venous drainage Anterior facial vein (lies deep to the Marginal Mandibular nerve) Lymphatic drainage Deep cervical and jugular chains of nodes

Answer 275

There is minimum mixing of blood passing through the vessels. Circle of Willis The two internal carotid arteries and two vertebral arteries form an anastomosis known as the Circle of Willis on the inferior surface of the brain. Each half of the circle is formed by: 1. Anterior communicating artery 2. Anterior cerebral artery 3. Internal carotid artery 4. Posterior communicating artery 5. Posterior cerebral arteries and the termination of the basilar artery The circle and its branches supply; the corpus striatum, internal capsule, diencephalon and midbrain. Vertebral arteries Enter the cranial cavity via foramen magnum Lie in the subarachnoid space Ascend on anterior surface of medulla oblongata Unite to form the basilar artery at the base of the pons Branches: Posterior spinal artery Anterior spinal artery Posterior inferior cerebellar artery ``` Basilar artery Branches: Anterior inferior cerebellar artery Labyrinthine artery Pontine arteries Superior cerebellar artery Posterior cerebral artery ``` ``` Internal carotid arteries Branches: Posterior communicating artery Anterior cerebral artery Middle cerebral artery Anterior choroid artery ```

Answer 276

Accessory nerve The accessory nerve has a superficial course and is easily injured. It lies under platysma and may be divided during the early part of the procedure. A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 277

Thoracodorsal nerve The long thoracic nerve is also at risk. The thoracodorsal nerve traverses the level 2 axillary nodes to supply latissimus dorsi and may be divided or damaged with diathermy. A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 278

Recurrent laryngeal nerve injury may complicate thyroid surgery in up to 2% of cases. A variety of different procedures carry the risk of iatrogenic nerve injury. These are important not only from the patients perspective but also from a medicolegal standpoint. The following operations and their associated nerve lesions are listed here: Posterior triangle lymph node biopsy and accessory nerve lesion. Lloyd Davies stirrups and common peroneal nerve. Thyroidectomy and laryngeal nerve. Anterior resection of rectum and hypogastric autonomic nerves. Axillary node clearance; long thoracic nerve, thoracodorsal nerve and intercostobrachial nerve. Inguinal hernia surgery and ilioinguinal nerve. Varicose vein surgery- sural and saphenous nerves. Posterior approach to the hip and sciatic nerve. Carotid endarterectomy and hypoglossal nerve. There are many more, with sound anatomical understanding of the commonly performed procedures the incidence of nerve lesions can be minimised. They commonly occur when surgeons operate in an unfamiliar tissue plane or by blind placement of haemostats (not recommended).

Answer 279

Pott's Eponymous fractures Colles' fracture (dinner fork deformity) •Fall onto extended outstretched hand •Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) •Volar angulation of distal radius fragment (Garden spade deformity) •Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture •Intra-articular fracture of the first carpometacarpal joint •Impact on flexed metacarpal, caused by fist fights •X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture •Dislocation of the proximal radioulnar joint in association with an ulna fracture •Fall on outstretched hand with forced pronation •Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture •Radial shaft fracture with associated dislocation of the distal radioulnar joint •Direct blow Pott's fracture •Bimalleolar ankle fracture •Forced foot eversion Barton's fracture •Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation •Fall onto extended and pronated wrist •Involvement of the joint is a defining feature

Answer 280

Bennett's Eponymous fractures Colles' fracture (dinner fork deformity) •Fall onto extended outstretched hand •Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) •Volar angulation of distal radius fragment (Garden spade deformity) •Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture •Intra-articular fracture of the first carpometacarpal joint •Impact on flexed metacarpal, caused by fist fights •X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture •Dislocation of the proximal radioulnar joint in association with an ulna fracture •Fall on outstretched hand with forced pronation •Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture •Radial shaft fracture with associated dislocation of the distal radioulnar joint •Direct blow Pott's fracture •Bimalleolar ankle fracture •Forced foot eversion Barton's fracture •Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation •Fall onto extended and pronated wrist •Involvement of the joint is a defining feature

Answer 281

Barton's Eponymous fractures Colles' fracture (dinner fork deformity) •Fall onto extended outstretched hand •Classical Colles' fractures have the following 3 features: 1. Transverse fracture of the radius 2. 1 inch proximal to the radio-carpal joint 3. Dorsal displacement and angulation Smith's fracture (reverse Colles' fracture) •Volar angulation of distal radius fragment (Garden spade deformity) •Caused by falling backwards onto the palm of an outstretched hand or falling with wrists flexed Bennett's fracture •Intra-articular fracture of the first carpometacarpal joint •Impact on flexed metacarpal, caused by fist fights •X-ray: triangular fragment at ulnar base of metacarpal Image sourced from Wikipedia Monteggia's fracture •Dislocation of the proximal radioulnar joint in association with an ulna fracture •Fall on outstretched hand with forced pronation •Needs prompt diagnosis to avoid disability Image sourced from Wikipedia Galeazzi fracture •Radial shaft fracture with associated dislocation of the distal radioulnar joint •Direct blow Pott's fracture •Bimalleolar ankle fracture •Forced foot eversion Barton's fracture •Distal radius fracture (Colles'/Smith's) with associated radiocarpal dislocation •Fall onto extended and pronated wrist •Involvement of the joint is a defining feature

Answer 282

Thyroidea Ima The brachiocephalic artery is the largest branch of the aortic arch. From its aortic origin it ascends superiorly, it initially lies anterior to the trachea and then on its right hand side. It branches into the common carotid and right subclavian arteries at the level of the sternoclavicular joint. Path Origin- apex of the midline of the aortic arch Passes superiorly and posteriorly to the right Divides into the right subclavian and right common carotid artery Relations ``` Anterior •Sternohyoid •Sternothyroid •Thymic remnants •Left brachiocephalic vein •Right inferior thyroid veins ``` Posterior •Trachea •Right pleura Right lateral •Right brachiocephalic vein •Superior part of SVC Left lateral •Thymic remnants •Origin of left common carotid •Inferior thyroid veins •Trachea (higher level) Branches Normally none but may have the thyroidea ima artery

Answer 283

This structure will be the rectus sheath and when entered the rectus abdominis muscle will be encountered. Abdominal incisions Midline incision •Commonest approach to the abdomen •Structures divided: linea alba, transversalis fascia, extraperitoneal fat, peritoneum (avoid falciform ligament above the umbilicus) •Bladder can be accessed via an extraperitoneal approach through the space of Retzius Paramedian incision •Parallel to the midline (about 3-4cm) •Structures divided/retracted: anterior rectus sheath, rectus (retracted), posterior rectus sheath, transversalis fascia, extraperitoneal fat, peritoneum •Incision is closed in layers Battle •Similar location to paramedian but rectus displaced medially (and thus denervated) •Now seldom used Kocher's Incision under right subcostal margin e.g. Cholecystectomy (open) Lanz Incision in right iliac fossa e.g. Appendicectomy Gridiron Oblique incision centered over McBurneys point- usually appendicectomy (less cosmetically acceptable than Lanz Gable Rooftop incision Pfannenstiel's Transverse supra pubic, primarily used to access pelvic organs McEvedy's Groin incision e.g. Emergency repair strangulated femoral hernia Rutherford Morrison Extraperitoneal approach to left or right lower quadrants. Gives excellent access to iliac vessels and is the approach of choice for first time renal transplantation.

Answer 284

Direct inguinal hernias pass through Hesselbachs triangle (although this is of minimal clinical significance!). Its medial boundary is the rectus muscle. Hesselbach's triangle Direct hernias pass through Hesselbachs triangle. Superolaterally Epigastric vessels Medially Lateral edge of rectus muscle Inferiorly Inguinal ligament

Answer 285

Mylohyoid is innervated by the mylohyoid branch of the inferior alveolar nerve. (trigeminal) Ansa cervicalis Superior root Branch of C1 anterolateral to carotid sheath Inferior root Derived from C2 and C3 roots, passes posterolateral to the internal jugular vein (may lie either deep or superficial to it) Innervation Sternohyoid Sternothyroid Omohyoid The ansa cervicalis lies anterior to the carotid sheath. The nerve supply to the inferior strap muscles enters at their inferior aspect. Therefore when dividing these muscles to expose a large goitre, the muscles should be divided in their upper half.

Answer 286

Both skin dimpling and nipple retraction are features of breast malignancy. However, they usually occur as a result of tumour infiltration of the breast ligaments and ducts respectively. The clavipectoral fascia encases the axillary contents. The lymphatic drainage of the breast is to the axilla and also to the internal mammary chain. The breast is well vascularised and the internal mammary artery is a branch of the subclavian artery. Breast The breast itself lies on a layer of pectoral fascia and the following muscles: 1. Pectoralis major 2. Serratus anterior 3. External oblique Breast anatomy Nerve supply Branches of intercostal nerves from T4-T6. Arterial supply •Internal mammary (thoracic) artery •External mammary artery (laterally) •Anterior intercostal arteries •Thoraco-acromial artery Venous drainage Superficial venous plexus to subclavian, axillary and intercostal veins. Lymphatic drainage •70% Axillary nodes •Internal mammary chain •Other lymphatic sites such as deep cervical and supraclavicular fossa (later in disease)