Surgical Anatomy Flashcards
Common shoulder conditions
Dislocation/instability
Impingement - irritated inflamed rotator cuff muscle tendons as they pass through subacromial space beneath the acromion resulting in pain, weakness and loss of movement.
Torn rotator cuff
Osteoarthritis
Anatomy of the shoulder
Sternoclavicular joint Clavicle Acromioclavicular joint Acromion Subacromial bursa Supraspinatus tendon Glenohumoral joint Glenoid labrum - fibrocartilage around scapula cavity for head of humerus to sit Subscapularis tendon Subscapularis muscle
Anatomy of rotator cuff
Subscapularis Long head of bicep Supraspinatus Infraspinatus Teres minor
Age and diagnosis of shoulder
10-30yrs most likely instability (more common in athletes, or people with collagen diseases with unstable ligaments)
40-60 more likely impingement syndrome
60-80 likely full thickness cuff tears or osteoarthritis as collagen generation ability declines
Shoulder stability and the glenoid labrum
Fibrocartilage attached around margin of glenoid cavity in scapula for head of humerus to sit in
Increases surface area
Increases depth by up to 50%
Acts as an attachment for ligaments and reduced shock
Resection reduces resistance to translation by 20%
Dynamic factors for shoulder stability
More important than static factors - i.e. glenoid labrum
Joint compression
60% compressive load is needed to dislocate shoulder
Can allow voluntary instability
Pathology of dislocation
External rotation twist causes shoulder to spin out, posterior cuff muscles contract and humeral head rips ligaments in from and tears glenoid labrum making more likely to repeat injury as muscles are now slackened if not repaired
Bankart lesion - damage to glenoid labrum due to anterior shoulder dislocation
Define arthroscopy
Key hole surgery
Minimally invasive surgical technique used on joints
Several basic portals of entry:
Initial posterior
Secondary anterior
Subacromial space space via further posterolateral and lateral portals
Further portals for specific tasks in more complex procedures
Describe impingement syndrome
Rubbing of rotator cuff tendons on acromion process - with age surface becomes irregular instead of smooth
Stage 1 reversible oedema
Stage 2 fibrosis and tendinitis leading to further swelling and further fibrotic process
Stage 3 bone spurs and tendons ruptures and frays
Test for syndrome- Hawkins tests: patient adducts shoulder, internally rotates bringing greater tuberosity under the acromion process - if this is painful it’s likely impingement.
Treatment- injection technique into subacromial bursa in subacromial space or arthroscopic subacromial decompression (bone removal) to flatten and smooth the bone to reduce tendon fraying.
Labrum and tendons stitched together again
Rotator cuff tears
Can be asymptomatic in 15-23% cases as the whole shoulder isn’t needed to function, perhaps only limiting lifting arms above head which in elderly people not common anyway so it goes unnoticed. Deltoid compensates even in supraspinatus etc. Is torn. In ages younger than 59 is 4-13% but above 60 is 20-51%.
Only sudden or gradually larger tears are symptomatic.
25-50% asymptomatic tears become symptomatic in two years
Symptoms relate to tear progression.
Rotator cuff tear treatment
Non operative:
Analgesia - pain relief
Physiotherapy
Activity lifestyle changes
Injection of pain relief eg steroid (long term questionable), anaesthetic and cortisone etc.
Surgical:
Stitch torn cuff muscles together for healing onto greater tuberosity
Zig zag row of tendons, latch down.
No adducting for 2 weeks
If the whole shoulder needs to be opened rather than keyhole surgery patients don’t often recover well
Post op rehabilitation - 3-4 weeks in sling, active movements and physio from then on, resistive movements from 12 weeks ie build strength
Osteoarthritis
Degenerative disease of joints most commonly synovial leading to loss of cartilage and bone changes
Phase 1- Chondrocyte injury
Phase 2- early OA, chondrocyte proliferates and secretes inflammatory mediators, collagen, proteoglycans and proteases. All act together to remodel cartilaginous matrix and initiate secondary inflammatory changes
Phase 3- late OA, repetitive injury and chronic inflammation lead to chronic inflammation and chondrocyte drop out, marked loss of cartilage and extensive subchondral bone changes such as eburnation (very smooth), subchondral cysts from bone fractures or osteophytes.
Primary - occurs in elderly more common in women begins at the 4th decade of life and function declines
Begins usually as wear and tear with repeated minor trauma, hereditary Factors, obesity, ageing etc. Contribute to degeneration.
Secondary - may appear at any age is the result of previous wear and tear like a fracture, inflammation and dislocation beginning the degeneration.
Osteoarthritis and surgery
Can resurface head of joint or replace the entire joint removing pain stimulus
Osteotomy - removal of bone to allow realignment
Arthroplasty - replacement
Arthrodesis - surgical immobilisation by bone fusion
Surgical approaches to shoulder
Aims to access the shoulder joint capsule without damage to nerve of major vessels
3 principal routes:
Deltopectoral- for trauma eg broken humerus, arthroplasty (joint replacement in arthritis), long head of bicep rupture and sepsis
Anterolateral- cuff repair access to subacromial space for tendon attachments, long head of bicep ruptured, acromioclavicular joint decompression, subacromial joint decompression
Posterior - fractures, dislocations, glenoid injury, loose body, sepsis, scapular neck fracture.
Deltopectoral approach in surgery
Access shoulder from the anterior
Cut through skin and fat into the deltopectoral groove all the way to the choroid process
Very constant anatomy here
Remain lateral to tendons as vessels lie medial to this
Into shoulder capsule through subscapularis tendon and expose surface of head of humerus
Branches of circumflex artery at risk here
Anterolateral approach to shoulder surgery
Follow intramuscular plane
Split deltoid muscle
Expose long head of biceps in bicipital groove
Risk of injury to the auxiliary nerve as this wraps around the head of the humerus however only the anterior deltoid would be affected so this poses less risk than posterior entry
Relatively easy approach but deltopectoral used more commonly due to risk of nerve damage in this technique
Posterior approach to shoulder surgery
Intervenous plane followed Not very common approach due to many nerves and vessels present at risk such as auxiliary which would paralyse entire deltoid and musculocutaneous nerve Detach deltoid Expose posterior joint capsule Reflect infraspinatus
Broken humerus case study
Bad break in upper shaft of humerus treated with rod and screws spanning whole bone
Recurrent falls and loss of proximal hold from the rod results in acromial impingement from compression onto shoulder joint
Remove metalwork and replace with bridging plate, more stable
If still fails then bone grafts and compression plate used to repair damage
Brachial plexus roots, trunks, divisions, cords and nerves
C5 and C6 roots join and branch dorsal scapula nerve and contribute to long thoracic - superior trunk branches subclavian and suprascapula nerves- anterior superior division branch posterior superior nerve to join posterior middle division - lateral cord branches lateral pectoral nerve - musculocutaneous nerve terminates branch contributes to median nerve with C8 and T1
C7 root contributes to long thoracic nerve - middle trunk no branches - posterior middle division sends anterior middle branch to join anterior superior division and joined by posterior superior and inferior from superior and inferior divisions respectively - posterior cord branches upper subscapular, thoracodorsal and lower subscapular nerves - radial nerve branches auxiliary
C8 and T1 join - inferior trunk - anterior inferior division branches posterior inferior branch to posterior middle division- medial cord branches medial brachial cutaneous, medial pectoral and medial anterior brachial cutaneous - branch contribute to median nerve with C5 and 6 and terminates in ulnar nerve
Musculocutaneous nerve
Roots c5-7 supplies three muscles; coracobrachialis, biceps brachii and brachialis
Terminates in lateral cutaneous nerve to forearm
Upper plexus lesion results in low of elbow flexion and lateral forearm numbness can be caused by shoulder dislocations or anterior shoulder surgery
Radial nerve
Roots c5-t1 is the posterior cord from posterior divisions of all three trunks
Lies posterior to auxiliary artery in Axilla
Passes posteriorly via triangular interval with profunda brachi artery
Supplies triceps brachi, anconeus and brachioradialis above elbow is a forearm extensor below elbow supplying extensor carpi radialis, and EXR brevis, extensor carpi ulnaris, extensor digiti minimus, extensor digitorum, extensor indicis, abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus
Sensory effects in wrist capsule through first webspace
Median nerve
Roots c6-t1 branches from medial and lateral cords
No branches in upper arm
Crosses brachial artery lateral to medial to medial boarder or biceps
Enters antecubital fossa medial to brachial artery and biceps tendon
Supplies palmaris longus, flexor carpi radialis, pronator teres, flexor digitorum superficialis and profundus I and II, flexor pollicis longus, pronator quadratus, abductor pollicis brevis, flexor pollicis brevis, opponens pollicis
Passes between two heads of pronator teres and travels through carpal tunnel giving recurrent motor branches to thenar eminence supplying LOAF muscles
Gives off palmar cutaneous branch 4 Cm before wrist
Ulnar nerve
Roots c8 and t1 from medial cord terminal branch
Stays medial in upper arm passes posterior to medial epicondyle within cubical tunnel
Enters medial forearm supplying flexor carpi ulnaris and ulnar half of flexor digitorum profundus
Pierces two heads of FCU travels deep to Flexor digitorum superficialis next to ulnar giving off palmar cutaneous branch
Enters hand via guyons canal and divides into deep motor and superficial sensory branches palmar cutaneous supplying medial palm.
Deep motor branch supplies intrinsic of hand except LOAF muscles (supplies by median)
Dorsal cutaneous branch 5cm proximal to wrist supplies dorsal hand provides digital sensation to the ulnar side for half the digits
LOAF muscles
Lateral two lumbricals
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
All supplied by median nerve branches
Brachial plexus lesions: erb-duchenne palsy
Inability to move forearm
Affects 1-2 in 1000 births
Caused by undue separation of head from shoulder (shoulder dystocia)
Risks - forceps delivery, vacuum extractor delivery, breach delivery, cephalic presentation with High birth weight above 4kg, prolonged labour and multiparity (twins etc)
Adult risks- fall onto shoulder or sudden axial load, dislocation, tumour (neuroma) and cervical rib arising from C7
Erbs palsy congenital
C5/6 or c7 born without (73-86% cases)
If c7 is involved causes loss of wrist and finger flexion as well as elbow causing true waiters tip
If c4 missing then diaphragm also involved
Just missing c5/6 can recover in three months if c7 involved there is 65% rate full recovery
C5-6 usually combination of musculocutaneous/axillary and median nerve involvement.
Musculocutaneous - loss of elbow flexion
Axillary and suprascapular - loss of shoulder abduction
Unopposed upper and lower subscapular nerve function causes internal shoulder rotation
Sensory loss of lateral upper arm
Waiters hand tip, abducted shoulder, internally rotated arm, extended elbow
Erbs palsy management
Initial support- limb immobilisation and splintage preventing further traction
Good prognosis mostly resolved in 9 months
Physio assisted
Stretch muscle groups preventing contracture
Positional splinting
Kinesiotaping - tape to treat pain by creating space between muscle and dermis layers
Electrical stimulation
Upper plexus lesions surgery - oberlin transfer
Fascicles of ulnar nerve sutured end to end to biceps branch of musculocutaneous nerve (non functional nerve)
Sacrifice FCU and FDS common more often FCU
to give function of elbow flexion from MC nerve
Usually motorcycle injury severing MC nerve
Successfully used in adults and infants obstetric palsy refractory to conservative treatment
Lower plexus lesion - klumpkes palsy
Less common- 1% of obstetric plexus lesions in total
More common in adult trauma eg motorcyclists
Caused by separation of arm from trunk
Roots c8-t1 with or without c7 are injured
Isolated lower root injury is least common
Loss of forearm supination, wrist and fingers are hyperextended
Good elbow and shoulder function
Claw hand - flexion of proximal interphalangeal and extension of metacarpalphalangeal joints
Horners syndrome - contracted pupil, dropping eyelid, local inability to sweat on one side of face due to sympathetic nerve damage in neck on that side.
Recovery is poor especially with horners syndrome below 50%
Peripheral nerve lesions of upper extremity - cubital tunnel syndrome
Ulnar nerve compression at elbow
Cubital tunnel bound by medial epicondyle and medial intermuscular septum anteriorly
Osborn’s fascia superficially
Compression from FDU distally and arcade of struthers (elbow ligament) proximally
Surgically releasing should correct
Carpal tunnel syndrome
Compression of median nerve without carpal tunnel
Occurs in pregnancy, hypothyroidism, rheumatoid arthritis, diabetes any condition with increased oedema
Causes tingling, pain, numb and weakness of wrist and hand
Treated by splinting, physio, injections and surgery to decompress nerve
Surgery- local anaesthetic incision in line with radial boarder of ring finger
Avoids motor recurrent branch of median nerve injury
Structures in the carpal tunnel
9 tendons and the median nerve surrounded by synovium - any condition involving synovial inflammation can cause carpal tunnel
Guyons canal and nerve compression
Ulnar nerve passes through bound by pisiform and hook of hamate
Nerve compressed in different zones gives different symptoms
Zone 1- just past the pisiform causes sensorimotor deficit symptoms
Zone 2- just before hook of hamate causes motor weakness, weak grip but still have sensation
Zone 3- sensory branch past hook of hamate causes sensory disturbance can be caused by H of hamate fracture, tumour, aneurism of ulnar nerve etc.
Treatment- surgery to decompress nerve or correct fracture etc. Causing compression
Dupuytrens disease
Nodular fibroproliferative disorder
Increases with age
Associated with trauma, certain drugs and liver disease
Not a flexor tendon disease but a sudden thickening of fascia and fibrosis causing a curled hand
Advanced stages can have growth of any fibres in the hand
Cords in the fingers can then displace nerves centrally creating disturbance in function further
Treatment- open fasciectomy, cut linearly directly over Palmer disease, expose neurovascular bundles and superficial and fascia attached disease. Excise cord and extend joints protecting nerve and artery. Stitch skin using zig zag incisions to lengthen skin present(Z-plasty).
Osteoarthritis of Carponetacarpal joint
Incidence increases with age associated with general OA
Higher incidence in manual workers
Pain at base of thumb, thenar weakness and wasting and z-deformity of thumb.
Ligaments stretched and allows joint to slide more and more causing hyper extension of MCP joint.
Treatment-
Non steroidal anti inflammatory drugs (NSAID)
Steroids/ hyaluronidase injections
Splintage to maintain muscle mass
Surgery- 70% cases avoid surgery for three years,
joint conserving,
replacement arthroplasty- reconstruction etc.
arthrodesis - fusion of bones
or excisional arthroplasty - trapiziectomy and reconstruction
Weilby technique
Describe the weilby technique
Used to correct osteoarthritis of the CMC joint with Z-deformity
Curved incision over CMC joint extending to wrist
Excise trapezium using osteotome pieces
Incise FCR tendon 50% of width and strip distally
Pass into trapezium cavity and wrap around abductor pollicis longus tendon
Wrap FCR and APL together and stitch remaining tendon into cavity
Free tendon holds tendons in place by trapezium and removes grinding and therefore pain, helps retain strength and corrects deformity
Z-deformity should be corrected and pain relieved
Colles fracture
Fracture 2-3cm proximal to the wrist joint in osteoporotic bone from falling on outstretched hands most commonly
Dinner fork deformity
Dorsal angulation and displacement, radial translation, supination, proximal impaction.
If severe can result in carpal tunnel syndrome due to deformity or haematoma
Needs emergency correction and decompression of tunnel
Treatment-
Manipulate under local anaesthetic and pull to correct level
Longitudinal traction to hold in place but is difficult in younger patients due to movement increasing deformity and reducing distal fragment causing flexion and ulnar deviation
Apply cast- from elbow to MCP joints leaving free fingers and thumb
Check positioning every 7-10 days radiologically
Remove plaster after 6 weeks and start mobilisation follow up physio.
If unsuccessful needs surgery- open reduction and internal fixation some cases may be suitable for wires
Longitudinal incision over PL tendon
Median nerve deep to this/adjacent radial artery is radial to tendon. Use retractors to hold all structures aside. Fracture of radius is beneath FPL and pronator quadratus 5cm distal of volar surface of radius. Plate follows natural curve of radius
Very successful function after
Complications- 3% people, complex regional pain syndrome caused by disturbance of sensory and autonomic supply and blood vessels. Median nerve damage. Rupture of EPL tendon(easy to hit as wraps around head of radius) stiffness, weakness and ulnar impaction.
Radio carpal joint normal indices
Ulnar naturally varies in length compared to the radius but usually equal give or take 2mm either side
Radial height is the distance from the tip of the radial styloid to the articular surface and is approx 11mm
Radial tilt is the angle of tangent across the articular surface compared to perpendicular
Loss of height of change in ulnar variance or loss of volar radial tilt is associated with poor grip strength and wrist function after a fracture - surgery aims to correct this
Smiths fracture
Reverse colles fracture
Falling on to flexed wrists
Distal radial fragment displaced volarly
Extremely unstable causing pain and flexion deformity of wrist
No cast possible as won’t correct properly
Barton’s fracture
An intra-articular fracture of distal radius with dislocation of Radiocarpal joint
Two types - dorsal and volar the latter being more common
Caused by fall on an extended and pronated wrist increasing carpal compression force on dorsal rim
Carpal displacement distinguishes fracture from a smiths or colles fracture
High risk patients have osteoarthritis and poor wrist function
Management of Barton’s and smiths fracture
Distinguish from colles
Spider-Man cast possible but very difficult - wrist supinated and fully extended
Usually needs open reduction - incision and correction of bone - and internal/external fixation
Open and closed reduction
Open - incision into fracture site and correction of bone position
Closed - correction of bone fracture without incision
Scaphoid fractures
Most commonly injured carpal bone
Typically from fall into outstretched hands
Diagnosed in x-ray but very hard to see so if suspicious use CT scan or MRI is most effective
Mostly heal with cast with thumb held but any displacement is best treated with screw fixation
Non union can be very serious causing persistent pain
Percutaneous fixation - cannulated screw to hold scaphoid in place
Vascularised bone graft - radial incision over scaphoid distal radius and scaphoid exposed. EPL, EPB and APL retracted
Window in distal radius made and cube of bone on soft tissue pedicle reflected forward
Gap made in scaphoid filled with bone graft and bone heals with blood supply from distal radius
Immobilise for 8-12 weeks
Salvage surgery for scapholunate advanced collapse SNAC
incision over Carpus Extensor tendons retracted Dorsal capsule incised Carpal bones identified Scaphoid excised and lunate/capitate/hamate/triquetral fused together with screws after bone prep/burring form rough edge
Subluxation of proximal interphalangeal joint
A partial dislocation
Once Dislocated becomes unusable and prone to further recurrent dislocations
Very difficult to operate as fingers favour fibrosis scarring and so stiffen when incised.
Operative technique hand supine with tourniquet
Transverse wire with centre of rotation in first phalange at PIPJ and parallel wire in second phalange
Bend wires 90degrees bear skin and attach longitudinal wires and slide spring mount over long wires and adjust accordingly
Left with H shape around finger
Steady improvement in range of post operative flexion in patients
Muscles important in hip surgery
Muscles attaching to the ASIS and the deep rotator muscles of the hip - obturator externus, internus, piriformis, gluteus minimus, superior gemellus, inferior gemellus, quadratus femoris.
Muscles attaching to the lesser trochanter aren’t as important more for pelvic surgery access than hip
Define extensile/non-extensile in terms of surgery
Extensile - very long continuation of an internervous plane (between the blood vessels and the nerves) so potentially could bring incision all way down limb etc.
Non-extensile - internervous plane is interrupted by nerve or vessel
Types of hip replacement
Hemi-arthroplasty - no replacement of acetabulum cup
Total arthroplasty includes cup replacing acetabulum
Approaches to hip replacement
Anterior - Smith Peterson
Anterolateral/lateral - Watson Jones, hardinge, charnley
Medial - ludloff
Posterior - Moore
Anterior approach to hip surgery
Used for DDH developmental dysplasia of hip
Synovial biopsies or washout of septic hip
Arthrodesis - surgical immobilisation of bone
Tumour excision
Trapdoor procedure for AVN avascular necrosis
Arthroplasty - hip replacement
Procedure - incision from anterior half iliac crest to the ASIS, curve incision down to run vertically for 8-10cm towards lateral 1/3 of patella. Lateral cutaneous nerve of thigh at risk - causes meralgia paresthetica loss of sensation in anterior thigh.
Follow internervous plane between sartorius (femoral nerve) and tensor fascia latae (superior gluteal nerve) superficially then deep follow between rectus femoris (femoral nerve) and gluteus medius (superior gluteal nerve)
Externally rotates leg to stretch sartorius and accentuate gap between this and tensor fascia lata
Divide fascia 2.5-7cm below ASIS avoiding lateral cutaneous nerve of thigh cut medial to tensor fascia lata and lateral to sartorius and retract muscles. Tie off lateral ascending branch of lateral cutaneous femoral nerve under tensor fascia lata.
Identify and detach two heads of rectus femoris
Strip gluteus medius and minimus from ilium surface and expose capsule of hip joint.
Shave off bone to expose little subchondral bone to fit implant In. Not cemented - biological implant
Smith Peterson anterior approach to hip surgery strengths and weaknesses
Good-
Good for paediatric surgery, protects blood supply
Minimally invasive
Can be extended for pelvic or acetabular repair
Good view of acetabulum
Bad-
Compromised view compared to other approaches
Not most commonly used
Can create bleeding
In field with key nerves eg femoral
Reputation for dislocation post operation
Difference between hemi arthroplasty and total arthroplasty of hip
Hemi - half, only head of femur replaced and fitted back into natural acetabulum, used in cases of neck of femur fracture, fragility fractures etc. (Fall From standing height or less - bones must be fragile to sustain this type of fracture)
Does eventually wear away acetabulum so use standard Exeter stem replacement so that they can fit an Exeter cup for acetabulum in when needed
Total arthroplasty - both acetabulum and head replaced at once
Anterolateral approach to hip surgery - Watson and sir John Charnley
Used for total joint replacement most common method
Open reduction and internal fixation of femoral neck fractures
Synovial biopsies of hip
Biopsies of femoral neck
Incision 2.5cm behind ASIS to tip of greater trochanter and along shaft of femur
No true internervous plane - glut med and tensor fascia lata have common supply - superior gluteal nerve
Incise fascia lata entering trochanteric bursa underneath it.
Watson Jones technique - anteriolateral, expose interval between gut med and TFL generally less destructive method of exposing capsule
Hardinge - direct lateral technique goes transgluteal
Charnley - trochanteric osteotomy removing trochanter - go underneath glut med and remove femur neck and head completely and reflect superiorly to expose capsule or go straight through gluteus medius.
Dangers of anterolateral approach to hip surgery
Ascending branch of left femoral cutaneous artery and veins pass deep to rectus femoris, TFL and gluteus medius all very close to muscles being incised but this isn’t often a problem
Inferior branch of superior gluteal nerve passes 4.5cm above trochanter in gluteus medius can cause excessive traction or injury leading to trendelenburg gait (weaker side of pelvis elevated causing better side to sag often a problem)
Sciatic nerve must be protected whilst dislocating head
Femoral nerve and vascular bundle are close by.
Strengths and weaknesses of anterolateral approach to hip
Charnley approach - easy to dislocate, excellent acetabular exposure, better alignment of hip components, extensile however lots of blood loss, long operative time, difficult to reattach trochanter and possibility of non union of bones, wire breakage and trochanteric bursitis (bursa inflammation causing pain) and cut muscle can scar causing adductor problems
Hardinge approach - usually compared to posterior approach has lower dislocation rate, sciatic nerve injury rate and preserves posterior tissue, extensile. However bad points are superior gluteal nerve injury, trendelenburg gait, limited acetabular exposure, abductor reattachment concern, can’t adjust trochanteric tension and not easy to lengthen and possibility of heterotopic ossification (bone growth in abnormal place)
Watson Jones - uncommon. Need heavy retraction to expose and can damage femoral artery, nerve and veins, very difficult exposure in musculature or obese patients and difficult to access femur. Extensile. Not so ideal for use in hip arthroplasty due to other techniques working better
Posterior approach to hip surgery
Most common for hip arthroplasty
Historically higher dislocation rate but now no longer should be the case if done well
Incision 10-15 Cm curved centred on posterior aspect of greater trochanter
Start 6cm above and posterior to the posterior aspect of greater trochanter
Curve across buttock and continue down shaft of femur
Incise fascia lata expose vastus lateralus
Split fibres of glut max in line with fibres
Retract glut med and min to reveal fat over short external rotators of hip
Identify muscles - piriformis most superficial and behind this is sciatic nerve in front of other rotators, retracting whole mass and sciatic nerve protects nerve
Box or t capsulotomy (flex hip 40 degrees to relax anterior capsule and iliofemoral ligament)
Dislocate hip
Cut 1cm back in tendons to protect ascending branch of medial circumflex artery - supply to femoral head!
Dangers of posterior approach to hip surgery
Sciatic nerve damage
Inferior gluteal artery and nerve damage - within 5 Cm to greater trochanter
Cruciate anastomoses at lower boarder of quad femoris is anastomoses of ascending branch of 1st perforator, descending branch of inferior Epigastric, medial and lateral femoral circumflex arteries
Strengths and weaknesses of posterior approach to hip
Good -
Avoid cutting abductors
Avoid complications of trochanteric osteotomy
Less heterotopic ossification (bone formation at abnormal anatomical site)
Easy exposure and faster rehabilitation
Extensile
Bad-
Increased risk of sciatic nerve injury causing foot drop
Increased risk of posterior dislocation
Increased infection risk
Medial approach ludloff to hip arthroplasty
Very uncommon aside from in paediatrics
Lower limb in frog position
Incision in skin, adductor longus for 6cm then incise aponeurosis
Internervous plane between all adductors and aponeurosis released by blunt dissection
Access lesser trochanter, psoas tendon and inferior femoral neck and head, anterior acetabulum
Minimally invasive
Anterior division of obturator nerve lies on obturator externus down medial thigh between adductor longus and brevis and gracilis
Posterior division of obturator nerve lies in obturator externus and down on adductor Magnus under brevis supplies obturator externus and adductor Magnus
Medial femoral circumflex artery passes round medial side of distal part of psoas - supplies entire femoral head
Good for DDH cases, good before walking age when no bony correction likely needed and some arthrogram advantages (imaging)
Weaknesses - all nerve and blood supply dangers
Risks associated with hip arthroplasty
Infection - 1% deep 2% superficial Bleeding Nerve injury deep vein thrombosis or pulmonary embolism from manipulation Dislocation Limb length discrepancy Fracture Loosening Revision or repeat surgery Persistent symptoms or pain stiffness Death Delayed/malunion or non-union of bone
Describe the knee joint
Largest joint in body
Modified hinge joint with flexion and extension and secondary rotational movements
Two types of joint - condylar (ovoid) from tibial femoral articulation and the saddle joint from the patella
Extension muscles - vastus lateralis, medialis, medialis and rectus femoris
Rotation muscles - sartorius, gracilis, semimembranosus
Flexion muscles - hamstrings; biceps femoris, semimembranosus, semitendinosus. Gastrocnemius, gracilis, sartorius and popliteus
Extensor mechanism injuries
Injury to the:
Quadriceps and tendon
Medial and lateral retinaculum
Patella and tendon/ligament
Tibial tubercle
Causes presentation patient can’t straighten leg or straight leg raise
Treatment: repair or reconstruct bones and or ligaments if possible, osteotomy, arthroplasty or arthrodesis
Patella- cannulated screw fix in place wires connecting screws to prevent compression splitting the bone
Ligament damage - very complex!
Extracapsular :
tendon quads tendon for patella
Lateral and medial collateral ligaments
Oblique popliteal ligament
Intracapsular :
Anterior and posterior collateral ligaments (ACL Has anterior medial and posterior lateral bundles, PCL has anterior lateral and posterior medial bundles)
Most surgeons only reconstruct either ACL or PCL due to difficulty of reconstruction
Anterior cruciate ligament injuries
Caused mostly by pivoting sports - skiing, basketball, rugby etc.
MRI used to determine, ligaments generally ruptured from femoral insertion
Choices of graft - hamstrings, patella BTB or allograft
Hamstrings have 10% weakness
Grafts taken from cadavers
Bone grafts can heal better than hamstring acts as fracture heal. Best method is debatable
Meniscus and injuries
Fibrocartilage
Load bearing function
Medial cup C shaped and smaller
Lateral is O shaped and larger
Medial is attached to the knee capsule and is more likely to tear
Lateral is more mobile not attached to capsule so less likely to tear
Very fragile blood supply making meniscal tears very difficult to heal - best healing is a tear within 3mm of the rim as this has the most supply of blood
Bucket handle tear- middle part sits in the middle due to tear on edge and Presents as cant extend knee past certain point - locking.
Can transplant in correct criteria of patient eg young, ACL in tact, good BMI etc.
Resection partially increased knee load by 65% or total increases peak load 235%
Osteotomy
Used for correction of varus (deformity involving displacement of part of limb toward midline)
Valgus (deformity away from midline)
In a stable joint with no inflammation and only pain in movement
In knees if patient ACL has been operated on or damaged then cannot have osteotomy due to dangers too great to perform operation
Arthroplasty for knees
Unicompartmental - only affected section replaced
Takes away less bone and soft tissue than total arthroplasty so should act more like native knee behaves more normally
Controversial
Total replacement leaves only collateral ligaments and epicondyles
If patient has torn ACL cannot have arthroplasty due to massive increase in surgery risk
Procedure -
Anterior approach - Midline incision into quad tendon on medial side of patella through retunaculum go round tendon to medial tuberosity
Lateral approach - Incision between tibia and gastrocnemius natural plane
Posterior - for fractures near the back, problematic as many vessels and nerves here. Once in the knee natural plane is present but many structures in the way.
Complications of knee surgery
Infection Bleeding Nerve injury Soft tissue injury DVT stiffness and swelling Fracture Dislocation Revision surgery needed
Movements of the foot
Supination - shift foot toward midline Pronation - away form midline Inversion Eversion (more ankle movement than pro and sup) Dorsiflexion Plantar flexion
Ankle anatomy
Fibula Tibia Talus Two joints Three main ligament groups - Syndesmosis Deltoid (medial) Lateral ligament complex Main movement is dorsi flexion around 20 degrees average and plantar flexion 45 degrees roughly in Sagittal plane
Talus shape and movement
Frustum shape (cone with pointy bit cut off) Moves roughly alone sagittal plane in hinge like movements very simple joint Very stable in dorsiflexion due to fitting against the tibia more but unstable in plantarflexion due to angle of joint therefore more likely to twist ankle in this position
Syndesmoses of ankle
Only fibrous joint in the limb on the ankle
Formed by interosseous membrane between fibula and tibia
Anterior inferior talofibular ligament from outer anterioinferior boarder of fibula to the neck of talus into distal articular cartilage function to restrain inversion in plantar flexion and resist anterolateral translation of talus in mortise
Posterior inferior talofibular ligament extends from posterior boarder of fibula to posteriolateral tubercle of talus function to help ankle stability (very strong) when lateral ligament complex is intact and is under greatest strain in ankle dorsiflexion and limits posterior talus displacement
Deltoid ligament of ankle
Very well vascularised heals very well and hardly ever needs surgery due to excellent blood supply
Formed of posterior tibiotalar part, Tibionavicular part And tibiocalcaneal part on the medial side of the ankle are very thick and well joined
Lateral ankle ligaments
Thinner and weaker than deltoid on medial side more likely to need surgery
ATFL most likely to rupture in ankle sprains - function to come forward off fibula and stop talus sliding so often gets overstretched and this increases arthritic risk from sliding and increased gap between bones
Achilles
PITFL
PTFL
calcaneofibular ligament
AITFL
ATFL
All much less vascularised than Deltoid do heal Less well
Why is the Ankle small surface area but transmits loads greater than hip or knee but is less likely to develop arthritis
Joint is very congruent fitting together well leaving little movement for bone to rub away cartilage etc.
Strong ligaments hold bones together very well preventing sliding
Very simple joint movements allowed compared to the knee or hip
Very unlikely to ever see primary arthritis only really every secondary arthritis following trauma to the ankle or ligaments etc.
Muscles of the ankle
Plantar flexors:
Gastrocnemius - crosses knee
Soleus
Plantaris - little contribution
Innervated by tibial branch of sciatic nerve mainly s1 and 2
Form common Achilles’ tendon for gastrocnemius and soleus
Dorsiflexors:
Tibialis anterior mainly
Peroneus tertius
Innervated by deep branch of perineal nerve mainly l4 and 5
Weber classification of ankle fracture
Weber A - fracture of fibula below line of syndesmosis - no injury to ligaments so long as bones heal ankle will become stable again, good prognosis
Weber B - fracture at line of syndesmoses most common type 70% of fractures from twisting ankle. Can be stable or unstable making management very difficult and therefore prognosis difficult unsure how best to treat
Weber C - higher fibula fracture above line of syndesmoses however to actually get this fracture force must have been great enough usually to also twist and tear syndesmoses ligaments so likely show complete ankle dislocation. Deltoid ligament also often torn very unstable break almost always needs surgery
Hind foot and triple joint
4 bones : talus, calcaneus, navicular and cuboid
3 joints that act as one (one can’t move without the other two also moving) : subtalar, talonavicular and calcaneocuboid joints
Responsive for inversion and eversion of heel (varus/valgus)
A valgus heel produces a flexible foot good for absorbing shock from impact like jumping etc.
A varus heel helps produce a stiff foot arch good for pushing off creating force for running etc.
Subtalar joint biomechanics
Subtalar joint of heel converts tibial rotation into forefoot supination and pronation and vice versa
This is due to axis of joint roughly 45 degrees to the foot therefore acts like a mitred hinge, twisting the forefoot or tibia causing the other to also rotate
This is useful for shock absorption as angle can help transfer impact to muscles rather than joints from rotation
Subtalar joint very important for shock absorption during gait or accommodating for uneven ground
Is important in energy conservation to make foot solid strut during toe off in gait cycle
Muscles of hind foot
Tibialis posterior most important hind foot inverter swinging heel into varus so that Achilles’ tendon pulls more in line and therefore is more efficient
Innervated by tibial nerve
Broad insertion into midfoot but mainly navicular and medial cuneiform
Passes behind medial malleolus
Peroneus brevis inserts into base of fifth metatarsal and is main Everter of foot
Peroneus longus inserts into base of first metatarsal and plantar flexes it
Both muscles innervated by superficial perineal nerve mainly l5
Hindfoot antagonistic muscle pairs
Tibialis posterior vs peroneus brevis
Tibialis anterior vs peroneus longus
A weak tib posterior leads to a flat valgus foot
Weak tibialis anterior and brevis leads to varus and cavus (very arched foot) eg caused by a demyelination disease etc. Other peripheral neuropathies
Talus injury’s
The talus is covered in cartilage not much soft tissue attachment meaning it’s prone to avascular necrosis due to lack of blood supply and hindfoot arthritis is more likely from dislocations etc:
Blood supply comes from perforating perineal arteries and anterior tibial artery and tarsal canal artery.
Tarsal canal and branch of anterior tibial anastomoses forming the sinus tarsi artery
Midfoot and lisfranc ligament
Navicular, cuboid, three cuneiforms and the tarsometatarsal joints
Key region for surgery - lisfranc ligament and second tarsometatarsal joint.
Lisfranc ligament very small from the medial cuneiform to the base of second TMT
The intermediate cuneiform next to medial recesses in where the base of second TMT sits tightly very strong and stable part of foot
Injury to this area would cause arch collapse and huge instability
Injury to ligament is very common in American football - 0.2% all fractures so not common elsewhere
Diagnosed with MRI
Poor prognosis very painful
Widening of TMTjoints and popping up of 1/2nd metatarsal
Surgery needed- longitudinal incisions on dorsal foot avoiding the dorsal pedal artery and deep fibula nerve
Other midfoot ligaments
Long and short plantar ligaments
Calcaneonavicular (spring) ligament
The head of talus rests on this ligament mesh and often tears this with talus damage
Forefoot anatomy
5 Metatarsalphalangeal joints, 1 interphalangeal joint, four proximal and four distal interphalangeal joints
Truss and windlass mechanism
Raising arch foot height increases foot stability
As arch rises toes are extended
As arch sinks toes are flexed touching floor giving more stability
Load spreading across foot using plantar fascia tightening and stretching from movement
Hallux valgus
Most common angular deformity of toes
Genetic predisposition from apes opposing toes or bad shoes
intermetatarsal angle widens and big toe (hallux) overlaps others
Doesn’t bend efficiently and likely prone to arthritis due to large gaps between bones
Rheumatoid arthritis rapidly advances this condition as it’s a disease that increases all joint instability
Treated with osteotomy - very straight forward to realign hallux appropriately
The earlier the better
Blood supply to the metatarsal head from the plantar artery can be detached accidentally causing avascular necrosis and arthritis which we don’t want
Forefoot blood and nerve supply
3 main arteries - posterior tibial, anterior tibial and peroneal artery formed at the trifurcation of the popliteal artery
Posterior tibial is main supply
Terminal branch of anterior tibial (dorsalis pedis) pierces through first intermetatarsal space to anastomoses with the plantar artery
Nerves -
Saphenous (terminal femoral branch) innervates medial ankle
Perineal, superficial and deep - deep innervates first webspace and superficial had largest area of dorsal foot and lateral ankle
Medial and lateral plantar and calcaneal nerves from tibial nerve - medial largest area of plantar medial foot and most toes, lateral the lateral, calcaneal the heel
Sural nerve - lateral plantar foot
Muscles of the foot
Instrinsic - lumbricals, interossei, short flexors, extensors and muscles of the hallux and fifth toe
Extrinsic - long flexors and extensors, dysfunction of these leads to claw toes etc.
Would rarely operate on plantar side of foot due to excess of muscle and neurovasculature present
Deepest layer- tibial posterior, peroneus longus and interossei
Next- two short flexors, one adductor
Next- two long flexors, lumbricals and quadratus plantae
Superficial layer- two abductors and flexor digitorum brevis
Baxter’s neuropathy
Nerve entrapment syndrome that results in compression of inferior calcaneal nerve
Toe deformities
Mallet toe - stubbing
Claw toe - muscle weakness
Hammer toe
Curly toe - common congenital problem from long flexors tightening
All descriptive of looks
The reconstructive ladder
Free tissue transfer Local tissue transfer Tissue expansion Skin grafts Delayed primary closure - If wound is infected then they clear the infection before closing the wound Primary intention Secondary intention
(Going up)
Wound healing overview
Haemostasis and coagulation
Inflammation
Proliferation and migration
Remodelling
Factors affecting wound healing : Infection Blood flow Steroids Malnutrition Diabetes Tension lines of skin Radio or chemotherapy
Main types of skin cancer
Squamous cell- can spread to lymph nodes and come back but if excised early small chance of return
Basal cell - doesn’t spread, least worrying. 4mm extra taken out around growth to ensure all is removed and won’t reoccur.
Melanoma - spreads and invades multiple skin levels. 2mm taken either side of tumour or often retake 2-3cm away
Managing skin cancer
Non surgical : Manage risk factors eg sun cream Topical treatments like cryo (freezing off) or chemotherapy Chemo or radiotherapy Surgical : Excision with or without reconstruction Management of regional lymph node basin
Types of burn
Superficial epidermal - epidermis damaged, skin reddens and swells but no blisters
Superficial dermal - epidermis and part of dermis burn, skin is pale pink and painful, small blisters
Deep dermal/partial thickness - epidermis and dermis damaged, skin red and blotchy, dry or moist and swollen and blistered. Painful or numb
Full thickness burn - all three layers of skin burnt and damaged tissue underneath may be blackened or pale while skin is dry and white/brown/black with no blisters skin may be leathery or waxy.
Why have heaters in burns units
Burns loose the protective barrier of skin so water loss and heat loss is significantly increased so need heaters and hydration constantly to maintain normal homeostasis
Types of skin graft
Full thickness - whole dermis generally used for smaller wounds on highly visible parts of body like the face as unlike split thickness grafts they blend in better with the skin around them and tend to have better cosmetics
Split thickness - removing epidermis and part of dermis moved and placed on recipient site
Graphs can have fenestrations in large graft areas to encourage the skin to stretch and so needing less skin to cover more area
Autograft - using patients own skin
Allograft - donor skin
Xenografts - donors skin from animals usually pigs
Geometric shapes and reconstruction
Geometric shapes especially in facial surgery can give better cosmetics and mean that skin graft isn’t needed from other body parts just use natural laxity of skin to move and stretch to cover exposed area
This can also allow following natural lines on skin eg wrinkles better hiding the scar
Faces have a lot of natural laxity so good to use this technique
Breast reconstruction tissue sources
Breast implant synthetic (not for chemo or radiotherapy patients as implant will shrink and become very painful)
Natural tissue sources-
Latissimus dorsi can be rotated round still attached to blood supply becoming breast tissue. regional flap as original blood supply isn’t removed. Is a sensational flap will have sensation
Insensate flaps- LSGAP from upper buttock or lower buttock
TUG flaps from medial thigh
DIEP, SIEA or free/pedicled TRAM flaps from stomach adipose tissue
Plugging arteries from donor tissue into internal thoracic arteries in Breast allows health tissue to remain.
Skull anatomy
Neurocranium derived from neural crest- protects the brain split into the calvarium (roof) and cranial base (floor).
Sections anterior to posterior: frontal bone with ethmoid bone in middle, sphenoid, temporal, occipital with parietal lateral to last three.
Viscerocranium compromises of (superior to inferior) - nasal bone medial, lacrimal, maxilla, zygomatic most lateral. Inferiorly is the mandible. Inside nose bits superior is palatine, medial the vomer and inferiorly the inferior nasal concha.
Laryngeal cancers
Mostly squamous cell
Can affect supraglottis, glottis or subglottis
Rate of cancer rose in men until early 1990s have fallen steadily since then
Hoarse voice common presentation
Supraglottic laryngeal carcinoma
Approximately 40% of laryngeal cancers
Usually present with dysphasia or metastatic neck node
Late presentation is common
Management - supraglottic laryngectomy and radiotherapy
Total laryngectomy reserved for residual or recurrent disease
Glottic laryngeal carcinoma
60% all laryngeal cancers
Usually presents early with dysphonia
Management - radiotherapy for early rumours 95% cure rate for T1 lesions
Total laryngectomy and neck dissection for residual or recurrent disease
Orbital rim fractures
Fracture of any bones forming the outer rim of bony orbit on face
Usually at suture line as this is weakest point
Seven bones forming: frontal, zygomatic, maxillary, lacrimal, ethmoid, palatine, sphenoid.
Orbital blowout fractures
Partial herniation of orbital contents through one of its walls
Usually caused by blunt trauma
Medial and inferior (floor) walls weakest most commonly floor
Entrapment of inferior rectus causes paralysis of upward gaze must check vision and eye movements rigorously
Won’t be able to look upward in damaged eye
Le fort classification
Floating palate fracture - below the nasal zone is fractured and separated
Floating maxilla- fracture from maxilla to eye sockets
Floating face/craniofacial fracture most severe fracture through maxilofrontal suture line slicing face in half
Mandibular fractures
Mostly left sided fractures as most people are right handed and punch people
Relatively common especially in men
Approximately 60% are bifocal
Present with trismus(jaw spasm), malocclusion(can close mouth properly), chin paraesthesia (disruption to mental branch of inferior alveolar nerve)
Frontal bone fractures
Needs significant force 100-200x greater than gravity
Present with forehead paraesthesia from damaged supraorbital nerve and rhinorrhea (nasal cavity filled with significant amounts of mucus fluid)
Embryology of Face
Development occurs mainly between 4-8 weeks gestation
Lower jaw (mandible) is the first to form at 4 weeks.
4th week- maxillary prominences and mandibular prominences form laterally. End of 4th week nasal placode develops (embryological nose)
Week 5- mesenchymal cells proliferate in lateral sides of nasal placodes to form medial and lateral prominences
Medial will form bridge and septum or nose lateral will form nostrils
Week 6- medial nasal prominences fuse
Week 7- maxillary prominences fuse with nasal prominences to form the palette
Cleft lip
During week 6-7 of gestation maxillary prominence fails to fuse with nasal prominences on both or either side during facial development creating cleft lip.
Unilateral incomplete cleft lip - one side of lip is partially non fused/formed
Unilateral complete - one side of lip is entirely not fused up to nostril
Bilateral complete - both sides of lip not fused up to nostrils
Causes feeding problems and speech problems later on in life so needs to be surgically corrected very early around 10 weeks old. If bilateral may do one side then the other separately.
Cleft palate
During week 6-7 of gestation maxillary prominence fails to fuse with nasal prominences on both or either side during facial development creating cleft palate. Often seen alongside cleft lip
Maxillary processes fail to fuse posteriorly.
Causes feeding and speech problems so needs surgery at around 6-10 months using a temporary palate fitted until surgery to allow feeding.
Unilateral incomplete - only posterior palate involved
Unilateral complete cleft palate and lip - whole palate and one side of lip involved
Bilateral complete cleft lip and palate - whole palate and both sides of lip non-fused and undeveloped
Sutures of skull
Fibrous joints unique to the skull
In adults the main sutures are : coronal (transverse across frontal), Sagittal (from occipital fontanelle to frontal) and lambdoid (transverse posteriorly through occipital fontanelle)
Join at frontal and occipital fontanelles
In children also have the Metopic suture from frontal fontanelle to anterior of frontal bone.
Metopic fuses before one years
Sagittal around 30 years
Coronal and lamboid around 25 years.
Craniosynostosis
Defined as premature fusion of one or more cranial sutures
Incidence between 1 in 2000 and 1 in 5000
Restricts growth perpendicularly to the fused suture
Compensatory growth at other cranial sutures
Trigonocephaly - only in children under 1 as Metopic suture normally fused by then. Frontal bone grows anteriorly but not transversely. Pointy head.
Scaphocephaly - fused Sagittal suture causes boat shaped head. Only anterior-posterior growth occurs no transverse. Try to surgically re-open Sagittal suture.
Plagiocephaly - fused coronal suture. Only one side fused early no growth transversely that side compensated growth on other side. Can be mistaken in children that lie on one side for long time deforms skull similar to this just due to infant skull pliability.
Brachycephaly - both coronal sutures fused shortened anterior-post growth excess transverse growth. Needs early management can be life threatening from airway obstruction/increased ICP needs frontal orbital advancement.
Embryology and anatomy of the pinna
Starts at 6 weeks gestation
First and second Branchial arches
Mesoderm condensed to form 6 hillocks of His
Hillocks fuse at week 12 to form auricle
Fully formed at 20 weeks
Reaches adult size at age 9
Each hillocks forms an anatomical location of the auricle : tragus, helical crus, helix, anti helix, antitragus, lobule.
Concha formed by first branchial grove ectoderm: concha cavum (middle), concha cymba (upper), intertragus incisor(lower)
Nerve supply from auriculotemporal (V3), lesser occipital (C2) and great auricular (C2+3).
Development of external auditory canal
8th week gestation
Thickening of ectoderm in first pharyngeal grove with grows towards middle ear
Concha cavum deepens
At 21 weeks ectodermal core reabsorbs
Competed by 28 weeks
Ossification occurs around age 3 and fully grown by 9
Embryology of Eustachian tube and middle ear
Starts at 3 weeks
Third pharyngeal arch enlarges and compresses the space between second pharyngeal arch and first pouch
Develops into the Eustachian tube and lateral out pouch becomes middle ear space
Pneumastidation of middle ear begins at ten weeks
Tympanic membrane appears at 28 weeks
Formed of three layers : ectoderm squamous layer, mesoderm fibrous layer, endoderm mucosal layer.
Middle ear is well formed at birth
Muscles of facial expression
All share common embryonic origin from second pharyngeal arch all innervated by cranial nerve 7(VII)
Groups of muscles: orbital, nasal and oral
Orbital group - orbicularis oculi muscle is split into outer part of orbit and inner palpebral part. Closes eyelid. Corrugator supercilii muscle is posterior to OO and draws eyebrows together to frown.
Nasal group - nasalis muscle has two parts; transverse and alar. Transverse compresses nares,alar opens them(flares nostrils). Procerus muscle pulls eyebrows downward. Depressor septi nasi muscle pulls nose inferiorly opening up the nares (flare nostrils).
Oral group - orbicularis oris muscle encloses the opening of oral cavity, closes and purses mouth. Buccinator muscle located deep to other facial muscles pulls cheek inward preventing build up of food in oral cavity.
Facial nerve paralysis upper and lower MN lesions
If an upper motor neurone lesion then forehead sparing is seen - wrinkles on forehead remain present and forehead has sensation
If lower MN lesion then entire face will have paralysis on side of lesion.
Head and neck cancer
Complex cancer and anatomy.
Disruption to speech, swallowing and cosmetics.
Types : oral, pharyngeal (oropharyngeal and naopharyngeal), laryngeal cancers
Managed with chemo or radiotherapy, surgery or palliative care depending on type and spread of cancer.
Oral cancers
90% oral cancers are squamous cell carcinomas
50% involved the tongue, tonsils next common
Associated with smoking, HPV and alcohol.
High prevalence in Indian subcontinent due to beetlenut chewing
Treated by surgery and radio/chemotherapy combo. Occurs commonly in glossopharyngeal arch, pharyngopalatine arch, palatine tonsil and tongue most frequently.
If surgery needed can use free flap from fibula along with peroneal artery and vein for blood supply to reconstruct cheek if has spread to mandible.
Pharyngeal cancers
Oropharyngeal - 75% squamous cell carcinoma, tonsils and faucial pillars most common sites, associated with smoking and HPV, usually present with throat pain or globus sensation. Usually treated with radio/chemotherapy. Surgery only in cases of neck node metastasis.
Nasopharyngeal - mostly squamous cell carcinoma associated with EBV/Chinese descent. Highest incidence in Southeast Asia and can invade through foramen ovale causing facial pain by cranial nerve 5. Some have protracted course with overall 5 year survival rate 60-80%
Maxillary fractures
Relatively straight forward unless fracture over infraorbital foramen where nerve facial travels through
Microtia
One in 7000
Failure of hillocks of his to develop and fuse
Can be uni or bilateral (3:1 unilateral) and more common in males in right ear.
Associated with multiple other pathologies. Graded 1-4 4 being nothing formed.
Patients usually wear clip on prosthetics or reconstructed using grafts at 5 years
Pre auricular sinus
Failure of the first and second hillocks to fuse or remnant of first brachial cleft
May become infected and excision needed
Sinus may extend long into ear canal or mandible where damage to facial nerve is possible
Generally large chunk of tissue removed to ensure all is gone
Bat ears
Missing anti helical fold of ear treated with pinnaplasty where ears are pulled back and helix is reformed
Furnas and mustarde sutures used on posterior of ear where skin has most loose adherence and can hide scar
If caught young enough can just use headband to pull ears back naturally.
External auditory canal
Redirects and redistributes sound
Lateral third has thick skin tightly adhered to underlying cartilage, hair and ceruminous glands
Inner two thirds has thin skin, no hair, very bony and very sensitive.
Nerve supply from the auriculotemporal nerve, lesser occipital, facial and vague nerves.
Eustachian tube anatomy
Runs anteromedially from middle ear to nasopharynx grows from 17-35mm in adults to produce an incline of 45 degrees
Medial 2/3 is cartilaginous lined by pseudostratified columnar ciliated epithelium while lateral third is bony and covered with cuboidal epithelium
Opened by tensor veli palatini (V3) and levator veli palatini (X)
Normal middle ear pressure kept at 200-300mmH2. Children often experience negative pressures muffling hearing
Tympanic membrane
Three layers - squamous outer layer continuous with external auditory canal, fibrous layer circular and radiating fibres and mucosal layer respiratory epithelium continuous with middle ear mucosa
Divided into pars tensa and pars flacida
Pars tensa - 80 and 55mmH2 area buckled on sound presentation converting sound to motion energy
The malleus is embedded in the tympanic membrane and energy transmitted to ossicular chain.
When viewing tympanic membrane can see lateral process of malleus, good for orienting as will always point anteriorly
Glue ear and otitis media
Infections of ear can lead to one another
Glue ear is fluid accumulation otitis media is pus and infection
Those with glue ear more commonly get otitis media problems
Otitis media is chronic while glue ear is acute
Surgical management- NICE guidelines for 12years or older, no Down’s syndrome or cleft palate patients qualify due to having different ear anatomy
Patients can have hearing difficulty, speech and language delay, ear infections or otalgia, nasal obstruction, behavioural problems, balance difficulties, tinitus and hyperacusis(very sensitive to sound)
Performed if better ear has hearing of 25-30dBHL or worse at 0.5,1,2 and 4 kHz or earlier if impact on social, educational status deemed significant.
Ventilation tubes inserted. Adenoidectomy maybe but not recommended in presence of frequent URT symptoms. Hearing them reassessed. Otovent balloon auto inflation may be considered during active observation.
Down’s syndrome and cleft palate have narrow ear canals and multiple pathologies so need MDT and hearing aids
Perforations and grommets
Perforations mostly heal on their own in the ear however if there is infection or complications then surgically need to close them.
Inserting a grommet to ventilate the ear drains the fluid and prevents reaccumulation
Internal acoustic meatus
1 Cm long
Runs in Petrous temporal bone
Perforated end plate at lateral end separating IAC from inner ear
Cranial nerves VII and VIII and labyrinthine artery and vein pass through end place to middle ear
Cranial nerve VIII divides into superior and inferior divisions
Middle ear
Located in petrous part of temporal bone
Includes tympanic cavity and and epitymapnic recess
Posterosuperiorly connects with mastoid air cells through the additus
Mucous membrane is continuous with Eustachian tube and mastoid
Contains - ossicles, tendons stapedius and tensor tympani, chorda tympani (CN VII) and tympanic plexus (CN IX)
