Orthopaedics Flashcards
Paediatric Elbow Fracture
XRAY:
anterior and posterior fad pad signs indicates haemarthroses - suggesting associated fracture
Displacement of the anterior humeral line
- Anterior humeral line should bisect the middle third of the capitellum on the lateral film
Displacement of the radio-capitellar line
- should intersect the capitellum on all views
- indicates radial head dislocation
Reduction in Baumann’s angle
- normally 8-28degrees
b)
Incidence of nerve injuries associated with supracondylar fractures is 10-20%. The median nerve and the radial nerve are most often injured.
Anterior interosseous nerve - inability to make “OK” sign
(loss of strength of the thumb interphalangeal joint in flexion as well as the index DIP joint in flexion. This injury renders the patient unable to perform the “OK” sign)
Radial nerve - inability to extend at the wrist
Brachial artery injury can lead to Volkmann’s contracture - compartment syndrome of the forearm.
c)
Management is based on the Gartland classification.
Type 1:
Nondisplaced or minimally displaced and are managed with long arm posterior splint with the elbow at 90 degrees of flexion and the forearm in a neutral position and outpatient referral to orthopedics within 7 days. Casting should be avoided because it can lead to compartment syndrome.
Type 2 fractures:
- Displaced with posterior cortex attached
- Closed reduction and immobilisation in ED + orthopaedic consultation
Type 3 fractures:
- Complete displacement
- Operative management
Shoulder Dislocation
ANTERIOR SHOULDER DISLOCATIONS
3 types:
- subclavicular
- subcoracoid
- subglenoid
Mechanism - abduction and external rotation
Early Complications:
axillary nerve injury most common
- pin prick over deltoid and abduction (though impractical in dislocated arm)
Hill-sachs lesion - fractured posterior lateral portion of the humeral head.
Bankart lesion - fracture of the glenoid rim
Greater tuberosity fractures
Capsule and labrum tears
Later complications:
- recurrent shoulder dislocations
- may require surgical repair of capsular tears and labrum detachment
Xray:
- Y view can show anterior dislocation
- AP view location of humeral head - subglenoid, subcoracoid, subclavicular
Management:
Analgesia:
- Intra-articular lignocaine - shoulder reduction suggests similar success rates but fewer complications, lower cost, and shorter ED length of stays with lidocaine injection
Regional block- US-guided interscalene nerve or suprascapular nerve blocks
Reduction techniques
External rotation technique:
- One operator
- patient supine or seated
- Starting position: Arm fully adducted at side with elbow flexed.
- Perform slow passive external rotation of arm
Milch
- one operator
- patient in supine
- Starting position: Arm fully abducted above the head with extended elbow. Apply longitudinal traction and external rotation of arm.
Cunningham
- One operator
- patient seated
- Starting position: Patient’s arm adducted, elbow at 90 degrees
- Operator faces patient. Place one hand on patient’s forearm applying downward traction.
- Other hand massages the trapezius, deltoid, and biceps
Traction-counter traction with axillary pressure
- requires 2 operators
- patient in supine (a lot of force usually requires procedural sedation)
- One operator provides a longitudinal traction force with the arm slightly abducted. Second operator provides countertraction (typically with a bedsheet wrapped around the thorax in the axilla).
Stimson
- patient in prone position
- Arm hangs off stretcher in 90-degree forward flexion and 5kg weights attached to affected arm (can combine with scapular manipulation)
- scapula manipulation - second operator attempts to adduct and medially rotate inferior border of scapula.
POSTERIOR SHOULDER DISLOCATION
- often missed injury (less painful, subtle xray findings)
- suspect it if the patient can’t externally rotate arm
- mechanism - seizure or electric shock
Xray:
- Rim sign (overlap between the humeral head and glenoid rim)
- Lightbulb sign
- Troughline sign
- A scapular Y view or axillary lateral view is essential to exclude a posterior shoulder dislocation, which may be missed in 50% cases.
- If in doubt get a CT scan
Associated injuries:
- Fractures of the humerus and the glenoid rim
- An isolated fracture of the lesser tuberosity
- A reverse Hill–Sachs lesion is seen in up to 80%
- Rotator cuff tears are present in up to 20%
- Neurovascular complications are uncommon.
Management:
- Ortho consult
Closed reduction in ED:
Indications - acute dislocation < 3weeks, articular defect <25%
- axial traction of the flexed and adducted shoulder
- direct pressure on the posteriorly displaced humeral head may facilitate the reduction.
Indications for surgical intervention:
- significant displacement of the lesser tuberosity that is irreducible on reduction of the dislocation
- an articular defect greater than 25%
- or a chronic dislocation (>3 weeks).
INFERIOR SHOULDER DISLOCATION (LUXATIO ERECTA)
- uncommon <0.5%
- mechanism = forceful hyperabduction
Complications:
- rotator cuff tear
- tear through the inferior capsule
- axillary artery and brachial plexus injury
- greater tuberosity fractures
Reduction:
- traction in the longitudinal axis of the humerus while an assistant applies countertraction with a folded sheet wrapped around the supraclavicular region
Joint Swelling
Differential diagnoses:
Septic arthritis (gonococcal vs. non-gonococcal)
- N. gonorrhoea
- S. aureus
- Strep. pneumoniae
Crystal induced arthritis (gout, pseudogout)
Reactive arthritis - post infectious with HLA-B27 susceptibility - associated with chlamydia urethritis
Seronegative spondyloarthropathies - ankylosing spondylitis
Autoimmune - rheumatoid arthritis, SLE
Rheumatic fever
Acute on chronic osteoarthritis
Lyme disease arthritis
Viral arthritis (parvovirus B19, Hep C, Hep B, HIV, EBV, rubella)
SEPTIC ARTHRITIS
WCC >50,000 with neutrophilia
gram stain positive for bacteria
flucloxacillin 2g QID (50mg/kg QID)
Vancomycin 25mg/kg loading if high risk for MRSA
cefazolin 2g TDS (50mg/kg TDS) is allergic to penicillin
clindamycin 600mg TDS (15mg/kg TDS) if allergic to penicillin and cephalosporins
GONOCOCCAL SEPTIC ARTHRITIS
- suspect in sexually active
- prodrome of migratory arthritis, tenosynovitis and vesiculopapular lesions to fingers
- synovial fluid is often negative for gonorrhoea
- need to take swabs of the posterior pharynx, urethra, cervix, rectum (as directed by sexual contact)
skin symptoms:
- keratoderma blenorrhagica
- stomatitis
- conjunctivitis
- treat gonorrhoea with ceftriaxone 500mg IM
CRYSTAL INDUCED SYNOVITIS (GOUT & PSEUDOGOUT)
- most common cause of monoarthritis affecting great toe and knee in men >40
uric acid (monosodium urate monohydrate crystals) = gout
calcium pyrophosphate = pseudogout
microscopic appearance:
Uric acid (gout):
- needle shaped and blue (negative birefringence)
Calcium pyrophosphate (pseudogout):
- rhomboid shape and yellow (positive birefringence)
30% of those with acute gout will have normal serum uric acid levels
pseudogout will have normal serum urate, calcium and phosphate levels
Treatment of gout
- prednisone 30mg daily - 5 days OR
- colchicine 1mg po, 500mcg 1hr later (once off)
HAEMARTHROSIS
traumatic - associated with ligamentous injury or intra-articular fracture
spontaneous in haemophiliacs/von willebrands - joint aspirations should be performed after factor replacement
Aspirate for comfort
Compression
Non-weight bearing
Reverse coagulopathy if present
REACTIVE ARTHRITIS
- is a seronegative spondyloarthropathy
- “the classic triad of Reiter’s syndrome is arthritis, urethritis and conjunctivitis”
- chlamydia is a common trigger
- enteric infections - post diarrhoea reactive arthritis (shigellar, yersinia, campylobacter, clostridium difficile, E. coli)
Bier’s Block
Prilocaine 0.5% 2-3mg/kg
duration of action 30-60min
Contraindications to biers block
- confused unco-operative patient
- uncontrolled hypertension SBP >180mmHg
- allergy to local anaesthetics
- bilateral upper limb humerus fractures
- compartment syndrome
- patient does not consent
- raynaud’s disease
- sickle cell disease
Stop procedure
Call for help
Ensure tourniquet/cuff inflated (inflate cuff to 100mm Hg above systolic BP)
- Support airway - jaw thrust / chin lift - Supplemental oxygen 100% high flow 15L NRBM
- Terminate prolonged seizure with IV Midazolam 2.5-5mg
- Seek and treat ventricular dysrhythmias with sodium bicarbonate 2mmol/kg IV, repeat every min
- Seek and treat cardiovascular collapse with intralipid 20% 1ml/kg IV bolus
(Intralipid contraindicated in soy, egg, penut allergic patients)
Lunate/Perilunate Dislocations
Reference Tintinalli’s
SCAPHOLUNATE LIGAMENT INJURY:
” The scapholunate ligament is the most commonly injured ligament in the wrist”
“Scapholunate dissociation is a widening of the scapholunate joint space of >3 mm on the PA view” - Terry Thomas or Madonna sign
Management with radial gutter slab
Referral to orthopaedic/hand surgeon
Often requires closed reduction with percutaneous pinning or open reduction and ligamentous repair
PERILUNATE AND LUNATE DISLOCATIONS:
- great force required i.e. MVA
- associated with scaphoid fractures in 65%
- median nerve injury and avascular necrosis
- Lunate dislocation (lunate no longer has contact with the radius)
- Perilunate dislocation (lunate still has contact with the radius)
- gross deformity is NOT usually present
- “piece of pie sign” or “spilled tea cup sign”
- requires emergency orthopaedic review
- closed reduction is often unsuccessful
COMPLICATIONS:
short term
- compression necrosis
- compartment syndrome
- median nerve injury
- avascular necrosis
long term
- early degenerative arthritis,
- delayed union,
- malunion,
- nonunion,
- carpal tunnel instability
- chronic pain or complex regional pain syndrome
- disability loss of work
- depression
Compartment Syndrome
Reference: Tintinalli’s
Irreversible muscle and nerve injury >8hrs
- atraumatic compartment syndrome - haemophilia and rhabdomyolysis
- crush injuries
- tibia fractures
CLINICAL FEATURES:
- severe pain out of proportion, refractory to opioids
- pain exacerbated by passive stretching of muscles in affected compartment
- parasthesia and paralysis
- perishing cold
- pulseless
- affected compartment feels tight and tender
DIAGNOSIS:
- compartment pressure measurement with a Stryker kit
- 2 measurements 5cm from fracture site
- measure pressure in unaffected compartment
- >35mmHg = compartment syndrome
features of rhabdomyolysis - urine for myoglobinuria
Posterior Hip Dislocation
Reference: Tintinalli’s
Posterior Hip Dislocation (80-90%)
- high force needed for native hips
- low force needed for prosthetic hips
- hip is adducted, shortened, internally rotated
- posterior dislocations in native hips is an orthopaedic emergency - needs to be reduced within 6hrs to prevent avascular necrosis
- sciatic nerve injury in 10%
Reduction Techniques:
- Allis manouvre
- Bigelow manouvre
- Captain morgans
