Orthopaedics Flashcards
How does compartment syndrome present? Which signs occur late?
Pain - out of proportion, on passive stretch
Parasthesia
Pallor
Swelling
Late - pulseless, perishingly cold, paralysis
Describe the pathophysiology of compartment syndrome
Pressure within a muscle compartment rises, due to fracture and swelling. Osseofascial pressure rises to more than venous pressure, forcing the veins to close and restricting venous drainage. This causes stasis of blood within the compartment and aviscious cycle of increased pressure.
Ischaemia occurs because the oxygen and metabolites are used up and the pressure is too high for arterial blood to perfuse the tissue.
Which 2 fractures most commonly cause compartment syndrome?
Tibial shaft
Supracondylar
What is the treatment for compartment syndrome?
Fasciotomy.
2 incisions either side of the tibia to reach all 4 compartments.
Which structures are at risk during a fasciotomy for tibial compartment syndrome?
Superficial peroneal nerve
Saphenous vein and nerve
What are the red flag symptoms of cauda equina?
Bilateral pain Saddle anaesthesia Bowel incontinence and bladder retention Reduced reflexes - anal wink, bulbocavernosus Reduced anal tone
What causes cauda equina?
Space occupying lesion eg tumour or disc prolapse compresses nerve root L1 or below. This affects all of the nerve roots below this point
What would you order if you suspected cauda equina?
Urgent MRI
Discectomy within 48 hours
What is the differential for a single acute painful joint?
Septic arthritis
Gout
Malignancy
Pseudogout Bursitis Transient synovitis (child)
What is the work up for a single acute painful joint?
FBC
CRP
Blood culture
Aspirate - culture, histology and crystal analysis
(For septic arthritis, malignancy and gout/pseudogout)
Which bacteria are associated with septic arthritis
Staph aureus
Neisseria gonorrhoea
Pseudomonas aeruginosa (immunocompromised)
Which bacteria are associated with an infected animal bite?
Pasturella multocida
What bacteria are associated with an infected human bite?
Staph aureus
Eikenella corrodens
What is the treatment for a bite wound?
Allow to heal by secondary intention.
7 days co amox or metro+doxy
Which nerve is at risk following a supracondylar fracture? How is it tested?
Anterior interosseous.
Can’t make ok sign because radial half of flexor digitorum profundus and flexor pollicis longus
What artery is at risk following a supracondylar fracture?What sign would you look for to check it?
Brachial artery
Check pulses
What is a major complication of a supracondylar fracture? What signs would you look for?
Volkmann’s ischaemic contracture.
Skin puckering - indicates puncture of brachialis
Signs of compartment syndrome: Pain out of proportion, passive stretch, swelling, parasthesia (pulse, cold, paralysis)
What is the difference between a buckle fracture and a greenstick fracture?
(Both are partial thickness breaks due to the pliability of paediatric bones)
Buckle - break is a crush on opposite side to the tension
Greenstick - break is a snap on the side of the tension
What is the difference between a Smith’s and Colle’s fracture?
Both - low energy (think elderly women) extra articular distal radius fracture
Colles - dorsally displaced
Smiths - volarly displaced
How would you manage a minimally displaced distal radial fracture?
Surgical fix because risk to pronation and supination even if slightly displaced.
How would you assess whether a distal radial fracture was displaced?
Volar tilt >11 degrees
Dorsal tilt >22 degrees
Which nerve is at risk in a distal radial fracture?
Median nerve - acute carpal tunnel syndrome
Which tendon is at risk in a distal radial fracture?
Extensor pollicis longus
How does a SUFE present?
11-14 years
Overweight
Hip pain (can present as knee pain)
FABER position - flexed, abducted and in external rotation
What complications are associated with a SUFE?
Avascular necrosis of the femoral head
Arthritis
How is a SUFE treated?
Single percutaneous screw
What is the blood supply to the femoral head?
Which is most likely to be occluded in avascular necrosis?
Medial and lateral circumflex arteries (from the deep femoral)
Obturator artery through the ligament to the head of the femur
MEDIAL circumflex
How would you investigate a possible SUFE?
Frog leg lateral hip xray
Easily missed on AP
Describe the Salter Harris classification.
I - Slip through the growth plate
II - Above. Through growth plate and up through metaphysis
III - Lower. Through the growth plate and down through the epiphysis
IV - Through both metaphysis, growth plate and epiphysis
V - Crush
What is the most common type of Salter Harris fracture?
II
What is the differential for a child with a limp?
Infection - osteomyelitis, septic arthritis, transient synovitis
Malignancy
Trauma/fracture
SUFE (11-14)
Perthes (3-11)
DDH (0-3)
How does most hip pathology present?
FABER position and shortened
Flexed, abducted, externally rotated
(Except dislocation which is internally rotated)
How does Perthes disease present?
Scrawny, chav child (3-11 years)
Decreased ROM, pain, Faber position
What is Perthes disease?
Idiopathic avn of femoral head in a child
How does AVN of femoral head look on an x ray?
Decreased epipyseal height
Increased density
How does developmental hip dysplasia occur?
Lax joint and shallow acetabulum causes the femoral head to develop outside the acetabulum in utero.
What is the treatment for DDH?
Developmental dysplasia of the hip.
Pavlik harness
Describe the tests performed on neonates to screen fro DDH
Ortolani - Out. Flex to 90 and abduct legs out. Push thigh up to reduce. Click is positive
Barlow - Back. Flex to 90 and legs together. Push back to dislocate. Click is positive.
What are the 4 defects involved with clubfoot?
C - midfoot cavus
A - forefoot adductus
V - hindfoot varus
E - hindfoot equinus
Not passively correctable
Where do the nerve roots emerge in relation to the vertebral disc in
a) The cervical spine
b) The rest of the spine
a) nerve root emerges above
b) nerve root emerges below
This is because there are 7 cervical vertebrae and 8 cervical nerve roots.
Which nerve root is being tested by the biceps reflex?
C5
Which nerve root is being tested by the supinator reflex?
C6
Which nerve root is being tested by the triceps reflex?
C7
How would you test the sensation and movement of C5?
Sensation - lateral shoulder
Movement - elbow flexion
How would you test the sensation and movement of C6?
Sensation - lateral forearm
Movement - wrist extension
How would you test the sensation and movement of C7?
Sensation - middle finger
Movement - elbow extension
How would you test the sensation and movement of C8?
Sensation - little finger
Movement - finger flexion
How would you test the sensation and movement of T1?
Sensation - medial forearm
Movement - finger abduction
How would you test the sensation and movement of L2?
Sensation - medial thigh/ groin
Movement - hip flexion
How would you test the sensation and movement of L3?
Sensation - medial and anterior thigh
Movement - knee extension
How would you test the sensation and movement of L4?
Sensation - medial calf
Movement - dorsiflexion (foot drop)
How would you test the sensation and movement of L5?
Sensation - Big toe round to lateral calf
Movement - toe extension
How would you test the sensation and movement of S1?
Sensation - Posterior calf
Movement - plantarflexion
Which nerve root is being tested by the knee reflex?
L3/4
Which nerve root is being tested by the ankle reflex?
S1
How would you test the sensation and movement of S4?
Sensation - Perineum
Movement - Anal tone, incontinence
What nerve might be damaged by axillary node clearance? What effect would it have?
Long thoracic
Serratus anterior
Winged scapula
Press hands on wall and it pokes out
What nerve might be damaged by fracture of the neck of the humerus or dislocation of the shoulder? What effect would it have?
Axillary
Deltoid
Arm abduction 15-90 degrees
Numbness in regimental badge area
What are the signs of damage to the long thoracic nerve?
Serratus anterior - winged scapula
What are the signs of damage to the axillary nerve?
Weakness in arm abduction 15-90 degrees
Numbness in regimental badge area
What are the signs of damage to the thoracodorsal nerve?
Latissimus dorsi weakness
Can’t use a crutch
What are the signs of damage to the median nerve?
movement and sensation
Thenar wasting Weakness in thumb adduction - palm on table and raise up Ok sign (anterior interosseous branch)
Carpal tunnel
What are the signs of damage to the ulnar nerve?
movement and sensation
1st webspace wasting
Weakness in abduction of fingers together
Ulnar claw - from damaged lumbricals
Pain/numbness in medial hand
What are the signs of damage to the radial nerve?
movement and sensation
Wrist drop
Pain/numbness on back of hand
What are the signs of damage to the anterior interosseous nerve?
Weakness in ok sign
What are the signs of damage to the superior gluteal nerve? (movement and sensation)
Trendelenberg gait
Pain over buttock
What are the signs of damage to the ilioinguinal nerve?
Pain from abdomen to groin
Illicited by pressing inguinal ligament
What are the signs of damage to the obturator nerve?
movement and sensation
Weakness in leg adduction
Pain in groin
What are the signs of damage to the common peroneal nerve?
movement and sensation
Foot drop
Pain around knee (common)
Circle between big and second toe (deep)
What are the signs of damage to the tibial nerve?
Weakness in plantarflexion
What are the signs of damage to the saphenous nerve?
Pain on medial/posterior calf
What are the signs of damage to the long cutaneous nerve of the thigh?
Pain on lateral and anterior thigh
What are the signs of damage to the superficial peroneal nerve?
Pain on anterior calf
What are the signs of damage to the sural nerve?
Pain on lateral/posterior calf
What are the signs of damage to the musculocutaneous nerve? (movement and sensation)
Pain/numbness on lateral forearm
Weakness in BBC muscles (brachialis, bicep brachii and coracobrachialis)
What nerve might be damaged by fracture of the shaft of the humerus? What effect would it have?
Radian nerve in the spiral groove
Wrist drop
Weakness in finger extension
What are the nerve roots of the long thoracic nerve?
C5 C6 and C7 (raise your hands up to heaven)
What are the nerve roots of the pudendal nerve
S2 S3 and S4 (poo and wee off the floor)
What are the nerve roots of the musculocutaneous, axillary, median, radial and ulnar nerves?
Musculocutaneous - C5, 6, 7 Axillary - C5, C6 Radial - C5, C6, C7, C8, T1 Median - C5, C6, C7, C8, T1 Ulnar - C8, T1
What are the signs of damage to the femoral nerve?
Weakness in knee extension, hip flexion
Pain/ numbness in anterior and medial aspect of the thigh and lower leg
What are the nerve roots of the femoral nerve?
L2-4
What are the nerve roots of the sciatic nerve?
L4 to S3
Which drug is useful in back pain, to reduce muscle spasm?
Baclofen
What are the causes of pathological fractures?
Osteoporosis Malignancy - primary or mets Paget's disease of the bone Metabolic bone disease Hyperparathyroid Osteogenesis imperfecta Infection - osteomyelitis
Name and describe some fracture patterns.
Transverse - straight across Oblique - diagonal Spiral Intra articular Segmental - 2 breaks leave a flail segment Comminuted - crushed into lots of pieces
How would you work up a suspected fracture?
2 planes x ray - AP and lateral usually
CT if comminuted
If repeated fractures/elderly Calcium Vitamin D PTH ?Biopsy MRI for nerve compromise
What are the contraindications for reducing a fracture
Undisplaced
Vertebral
Give some immediate fracture complications.
Nerve palsy
Ischaemia
Haemorrhage
Give some early (but not immediate) fracture complications.
Compartment syndrome
Infection
DVT
Fat embolus
Give some late fracture complications.
Non union Malunion Stiffness AVN CRPS - complex regional pain syndrome
How do you describe an x ray of a fracture?
Name age and date of x ray
This is a (lateral, AP, PA ..) of the …
The most obvious abnormality is..
Which bone
Where (epiphysis, metaphysis, diaphysis)
Pattern (transverse, oblique, spiral, segment, comminuted)
Displacement?
Angulated?
Shortened?
Rotated?
How do you describe an x ray of a bone lesion?
Name age and date of x ray
This is a (lateral, AP, PA ..) of the …
The most obvious abnormality is..
Which bone Where (epiphysis, metaphysis, diaphysis) Lytic or sclerotic Cortex or medulla Through the periosteum? Well defined border? Periosteal thickening?
What is the name for a radiculopathy of the lateral cutaneous nerve of the thigh?
Meralgia paraesthetica
What are the risk factors for dupuytrens contracture?
Manual labour Phenytoin Alcoholic liver disease Trauma FHx
What is the treatment for an intracapsular NOF?
Mobile - total hip replacement
Not mobile - hemiarthroplasty (cement)
What is the treatment for an intertrochanteric NOF?
Dynamic hip screw
What is the treatment for a subtrochanteric NOF?
Intramedullary nail
How does De Quervains tenosynovitis present?
Swollen side of wrist
Pain over ther radial styloid on forced abduction/flexion of the thumb.
Describe the parts of an intervertebral disc. What type of collagen makes up each part?
Annulus fibrosus (outside) - type 1 collagen Nucleus pulposus (inside) - type 2 collagen
Which direction does an intervertebral disc normally herniate? Why?
Posterolaterally
Because the posterior longitudinal ligament is the weakest
Describe the layers of the back that the needle of a spinal anaesthetic must pass through.
Supraspinous ligament Interspinous ligament Ligamentum flavum (Epidural here) Dura mater Arachnoid mater (Spinal here)
(Then Pia mater The cord Other sides of the meninges Posterior longitudinal ligament Vertebral body/disc Anterior longitudinal ligament)
At what spinal level do most episodes of cauda equina occur?
L4/5
Pressing on L5 nerve root (toe extension)
L5/S1
Pressing on S1 nerve root (plantarflexion)
What are the main causes of radiculopathy?
Disc herniation
Degenerative - spondylosis
Arthritic osteophytes
Diabetes (microvascular damage to nerves)
Describe the first 2 vertebrae
Atlas - C1. A ring shape
Axis - C2 Has the dens which slots into C1 to allow rotation of the head
Describe the femoral and sciatic stretch tests. What do they identify?
Sciatic - passive straight leg raise in dorsiflexion
Femoral - passive hip extension with knee in flexion
Stretch the nerves to illicit radiculopathy pain
Describe some special x ray views
Frog leg lateral - for SUFE
Scaphoid view - scaphoid fracture
Give a differential for back pain
Mechanical - muscular, disc herniation, arthritic changes (spondylosis), inflammatory (spondylitis), compression fracture
Systemic - discitis, malignancy, connective tissue disease
Referred - renal colic, AAA, pancreatitis
What are the borders of the anatomical snuff box?
Extensor pollicis longus
Extensor pollicis brevis
Abductor pollicis longus (b for thumB)
What complications are associated with a scaphoid fracture? Why?
Non union
AVN
Blood supply travels distal to proximal
What are the risk factors for a NOF?
Female
Age
Osteopenia/osteoporosis
Why do we measure lactate in trauma/sepsis?
Marker of uncompensated hypoperfusion.
Therefore marker of morbidity/AVN in fractures/ischaemia risk
Associated with poor outcomes
The consultant asks you to prep a patient for theatre for a total hip replacement. What do you do?
Fbc, u and e, group and save 2 units, lactate
Fluid
Nil by mouth
Reverse Warfarin and place on Rivaroxaban (for knee and hip surgery, all others use LMWH)
Place on sliding scale if insulin dependent
Bactoban and hibiscrub for MRSA prophylaxis
Describe Gardner’s classification for NOFs.
I - Incomplete
II - Complete, undisplaced
III - Complete, partially displaced
IV - Complete fully displaced
Describe the Nottingham Hip fracture score.
Risk of 30 day mortality high if 7/10
Age - 66-85 3 points, over 85 4 points Sex M more likely to die even though F more likely to fracture Mental state Hb In a home Comorbidities Cancer
What is the 1 year mortality following a NOF?
30%
What are the complications associated with an untreated intracapsular NOF?
AVN
Non union because no periosteum in femoral neck therefore no callus
Pain
Disability
Mortality 30%
What are the complications associated with a hip arthroplasty?
Any op - Infection Bleeding NV damage Chronic pain Anaesthetic reaction
Specific-
Leg length discrepancy
Stiffness
Dislocation
What are the complications associated with an untreated extracapsular NOF?
Pain
Disability
Mortality 30%
How does ankylosing spondylitis present?
Lower back pain and stiffness of insidious onset
Stiffness worse in the morning and improves with exercise
Night pain
Reduced lateral flexion Reduced forward flexion - Schober's test - a line is drawn 10 cm above and 5 cm below the back dimples. The distance between the two lines should increase by more than 5 cm when the patient bends as far forward as possible Reduced chest expansion Bamboo spine Sacroilitis
What are the risk factors for an spond?
Male
HLA-B27
How is ank spond treated?
Regular exercise such as swimming
Physiotherapy
NSAIDs are the first-line treatment
‘Anti-TNF therapy should be given to patients with persistently high disease activity despite conventional treatments’ (etanercept and adalimumab)
How does osteoarthritis present?
Gradual onset Assymetric joint pain Knee, hip, pip and dip Less than 1 hour morning stiffness Relieved by rest
What are the radiological features of osteoarthritis?
L - loss of joint space
O - osteophytes
S - subchondral cysts
S - sclerosis
What is the treatment of osteoarthritis?
Weight loss Physio Paracetamol NSAIDs Steroid injections Joint replacement
What complications of osteoarthritis?
Gout Pseudogout Chondrolysis and loose bodies Stress fractures Radiculopathy
What are the risk factors for osteoarthritis?
Obesity Varus/valgus deformities Repetitive microtrauma (pneumatic drill) Gout Pseudogout Menopause
What are the indications for a joint replacement for osteoarthritis?
Pain - Steroid injections no longer effective Night pain Pain when resting Startup pain
Affecting activities of daily living
What are Heberdens and Bouchards nodes?
Heberden - at the end - DIP joint
Bouchard - PIP joint
Both associated with osteoarthritis
Hard bony outgrowths caused by osteophytes
Which type of bone is most affected by osteoporosis?
Cancellous spongy bone
What is the difference between normal and osteoporotic bone?
Decreased density, especially in the cancellous bone. Thin trabeculae and increased numbers of Haversian canals (parallel to the length of the bone)
What are the main risk factors for osteoporosis?
FRAX factors:
Female Fractured hip Rheumatoid arthritis Alcohol Age Smoking Steroids Low BMI
Endocrine - hyperthyroid, parathyroid, premature menopause, acromegaly
Early menopause
CKD
What is the FRAX score?
FFRAASSL
Female Fractured hip Rheumatoid arthritis Alcohol Age Smoking Steroids Low BMI
Risk of fracture in osteporosis
When is a DEXA scan indicated?
Fracture plus
Minor trauma Steroids Rheumatoid arthritis Early menopause Post menopause and low BMI
What is the treatment for osteoporosis?
Bisphosphonates (alendronic acid)
Adcal
What is the mechanism of action of bisphosphonates?
Cause apoptosis of osteoclasts
What are the side effects of bisphosphonates?
GORD (acidic)
Hypocalcaemia
Osteonecrosis of the jaw
What is the bone profile blood result likely to show in osteoporosis?
Normal
What is the difference between the pain presentation of osteoporosis and osteomalacia?
OsteoPorosis hurts part of the time, osteoMalacia hurts most of the time.
Which types of bone are at most at risk of fracture in osteomalacia?
Flat bones - pubic rami, scapula, ribs
What is the bone profile blood result likely to show in osteomalacia?
Low vit D
Thererfore Low Ca
Therefore High PTH and High Alk phos
What is the pathophysiology of Paget’s disease of the bone?
Large multi nucleated osteoclasts
Increased breakdown of bone, stimulates increased osteoblastic activity.
Lots of thick bone - sabre tibia and skull
Due to high demand, the bone produced is low quality, weak, vascular.
What complications are associated with Paget’s disease of the bone?
Fractures
Arthritis
Osteosarcoma (high bone turnover)
Deformity
What is the bone profile blood result likely to show in Paget’s disease of the bone?
High Alk Phos (high bone turnover)
What is the bone profile blood result likely to show in bone mets?
High alk phos (high turnover)
Enough to increase Ca
What is the bone profile blood result likely to show in primary hyper PTH?
High PTH
Therefore high Ca
What is the bone profile blood result likely to show in secondary hyper PTH?
Low Ca
Therefore high PTH
What are the most common cancers to metastasise to the bone?
Prostate
Breast
Lung/bronchial
(and the rest of the hexagon)
Thyroid
Kidney
Which bone mets are more likely to be lytic and which are more likely to be sclerotic?
Lytic - thyroid, bronchial, renal
Sclerotic - Prostate, breast
How do bone mets develop?
- Cancerous cells have less e-cadherin on the membrane. This leads to reduced adhesion between cells.
- Cancer cells recruit niche cells to release lots of protease to lyse the surrounding stroma.
- Cancer cells enter the blood/lymph/coelom
- Cancer cells release integrins to aid adhesion to the endothelium in the bone.
- Cancer cells release VEG-F to increase angiogenesis at the bone.
- Lytic cancer releases GF to stimulate blasts to stimulate clasts.
- Sclerotic cancer releases ET-1 to increase blasts.
Which bones do malignant lesions commonly develop in?
Thoracic spine
Proximal femur
What are the red flag signs and symptoms for a bone met?
Night pain Progressive pain Pathological fracture Neurological deficit - spinal cord compression Hypercalcaemia
Weight loss
Appetite loss
Smoker
What are the early symptoms of hypercalcaemia?
Stones…
Polyuria
Renal stones
Moans…
Pancreatitis
Constipation
Vomiting
Groans….
Depression
Fatigue
What are the late symptoms of hypercalcaemia?
Cardiovascular
Short QT -> arrhythmia
Renal tubular damage - electrolyte disturbance, AKI
What is the differential for causes of hypercalcaemia?
Malignancy
Paget’s disease of the bone
HyperPTH
Sarcoid
TB
CKD
Lithium
How is hypercalcaemia treated?
Loop diuresis + fluid
Bisphosphonates
What tests would you order if you suspected a bone met?
Fbc - anaemia of chronic disease, polycythaemia from EPO secreting renal cell cancer, neutrophilia
LFT - Alk phos
Bone profile - PTH, serum calcium
PSA, U&E, serum thyroxine - to hunt the primary
CXR
X ray limb in 2 planes
CT chest abdo pelvis
Technitium bone scan
MRI if neuro compromise
Biopsy - carried out by resecting surgeon
What test can most sensitively identify bone mets?
Technitium bone scan
Identifies hotspots
What is the most common primary bone tumour?
Osteoid osteosarcoma
How does osteoid osteosarcoma present?
Young adult
Distal femur
On xray
Sclerotic
Elevation of periosteum
Sunray spicules
How does Ewings’ sarcoma present?
Child
Flat or long bones
On x ray
Lytic
What are the causes of duypeytren’s contracture?
Thickening of the palmar fascia
Idiopathic (FHx) Cirrhosis Phenytoin Trauma Manual labour
How does tenosynovitis present?
Pain over radial styloid on forced flexion of the thumb
Finkelstein test
How does tennis elbow present?
Lateral epicondylitis
Pain on wrist extension when elbow flexed
How does golfer’s elbow present?
Medial epicondylitis
Pain on wrist flexion when elbow flexed
Which bursa is affected by Housemaid’s knee?
Prepatellar
Which bursa is affected by Clergyman’s knee?
Infrapatellar
Why does damage to the radial nerve in the spiral groove only cause mild weakness of elbow extension?
The branches to the long and medial heads arise proximal to the radial groove