Usually seen motor vehicle accident

Joint contact area:

40% femoral head is in contact with acetabular articular cartilage
10% femoral head is in contact with labrum

Emergent treatment: closed reduction

Dislocated hip = emergency
Goal: reduce risk of avascular necrosis and degenerative joint disease
Requires anaesthesia and muscle relaxation

Allis Manneuver
- Assistant stabilised pelvis
- Surgeon stand on stretcher and gently flexes hip to 90 degrees, applies progressively increasing
traction to the extremity with gentle adduction and internal rotation
- Reduction is seen and felt
Following closed reduction
- Check stability of hip at 90 degrees flexion
- No flexion >60 degrees
- Early mobilisation
- MRI at 3 months
- Repeat AP pelvis
- CT w thin cuts through acetabulum
- R/O bony fragments within hip joint  if present = emergent surgery

Posterior Hip Dislocation: Mechanism of Injury

Almost always due to high-energy trauma
Most commonly caused by impact of dashboard on knee

Anterior Hip Dislocation

7 – 10 % cases
Mechanism: forced abduction w external hip rotation, anterior capsule is torn or avulsed, femoral head
levered out anteriorly

Effect of Dislocation on Femoral Head Circulation

- Disrupts artery of ligamentum teres
- Kink or compress ascending cervical branches
- Early reduction = improves blood flow to femoral head
Sciatic Nerve Injury
- 10% adults and 5% in children
- Resolve with reduction and time
- Piercing or transection of nerve by bone can occur
- Peroneal nerve affected more
- Sciatic nerve palsy: if no improvement after 3 – 4 weeks

Physical Examination: classical appearance

Posterior dislocation:
- Hip flexed
- Internally rotated
- Adducted
Reduction Manneuvers
Allis
Stimson: patient prone, hip flexed and leg off stretcher, requires one person
Complications
- Avascular necrosis 1 – 20%
- Results are best if hip reduced within 6 hours
Post-traumatic osteoarthritis
- Can occur with or without avascular necrosis

Recurrent Dislocation
Rare, unless an underlying bony instability has not been surgically corrected
Mechanism of Injury Associated Injuries
High energy Nerve injuries
- Motor vehicle crash - Peroneal nerve injury – 25%
- Crush injury - Tibial nerve injury
- Fall from height Fractures: present in 60% dislocations
Low energy Soft tissue injuries
- Athletic injury - Patellar tendon rupture
- Routine walking - Periarticular avulsion
- Displaced menisci
Hyperextension injury leads to anterior dislocation Ligamentous injury
- ACL, PCL, posterolateral corner
Posteriorly directed force across the proximal tibia - LCL, MCL
(dashboard injuries) Vascular Injury
Leads to posterior dislocations - Intimal tear
- Obtain ABIs and arteriogram

Physical Exam Vascular Exam

- No obvious deformity If pulses are present and normal it does not mean
- 50% spontaneously reduce before arrival to there is absence of injury
ED
- Subtle signs of trauma Measure Ankle-Brachial Index (ABI) on all
- Rule out vascular injury: palpate the dorsalis patients
pedis and posterior tibial pulses on injured and If ABI >0.9
contralateral side - Monitor w serial examination
Reduce immediately IF absent pulses If ABI <0.9
- Perform arterial duplex US or CT
angiography

Treatment If arterial injury confirmed  consult vascular

Nonoperative surgery
- Emergent closed reduction followed by
vascular assessment If pulses are absent or diminished
- Immobilisation as definitive management Confirm that knee joint is reduced or perform
- Worse out comes seen with nonoperative immediate reduction and reassessment
management - Immediate surgical exploration if pulses
Operative are still absent after reduction
Open reduction, indications: - Ischemia time >8 hours amputation rates
- Irreducible knee are as high as 85%
- Posterolateral dislocation
- Open fracture If pulses present after reduction
- Obesity - Measure ABI then consider observation
- Vascular injury vs angiography
External fixation, indication
- Vascular repair
- Open fracture
- Compartment syndrome
- Obese
- polytrauma
Treatment cont. Complications
Delayed ligamentous reconstruction/repair, indications Vascular compromise
- Instability - 40 – 50% cases
- Emergent vascular repair

Stiffness (arthrofibrosis)
- Most common complication
- More common with delayed mobilisation
- Treatment: arthroscopic lysis of adhesion,
manipulation under anaesthesia

Laxity and Instability

- Treatment: bracing, revision
reconstruction

Peroneal Nerve Injury

- RF: anterior dislocation
- Treatment: neurolysis, nerve repair or
reconstruction
Epidemiology Clinical Examination
Anterior: most common - Examine axillary nerve: deltoid function
Posterior: uncommon, electrocutions, seizures - Examine M/C nerve: biceps function
Inferior (Luxatio Erecta): rare, hyperabduction Radiographic Evaluation
injury - True AP shoulder
- Axillary lateral
- Scapular Y
- Stryker Notch view (Bony Bankart)
Anterior Dislocation Recurrence Rate
Age 20: 80 – 92%
Age 30: 60%
Age >40: 10 – 15% Posterior Dislocation
Electrocution and seizures cause overpull of
Look for concomitant injuries: subscapularis and latissimus dorsi
- Bony: bankart, Hill-Sachs, glenoid - Light bulb sign
fracture, greater tuberosity fracture - Vacant glenoid sign
- Soft tissue: subscapularis tear, RCT
- Vascular: axillary artery injury (older pt) Reduce with traction and gentle anterior translation
- Nerve: axillary nerve neuropraxia

1. Traumatic
2. Atraumatic (congenital laxity) Inferior Dislocations
3. Acquired (repeated microtrauma) Luxatio Erecta
- Hyperabduction injury
- Arm presents in a flexed posture
- High rate or nerve and vascular injury
- Reduce with in-line traction and gentle
adduction

Treatment
Nonoperative
Closed reduction performed, techniques:
- Traction/countertraction: sheet wrapped around the patient and one around reducer
- Hippocratic technique: one foot placed across axillary folds and onto the chest wall
- Stimson technique: patient placed prone with affected extremity allowed to hang free
- Milch technique: arm abducted and externally rotated with thumb pressure applied to humeral head
- Scapular manipulation
Post reduction
- X-ray to confirm position of humeral head
- Pain control, immobilisation for 7 – 10 days then begin progressive ROM
Operative indications
- Irreducible shoulder
- Displaced greater tuberosity
- Glenoid rim fractures >5mm
- Elective repair for younger patients
Epidemiology Mechanism of Injury
11 – 28% injuries to the elbow Most commonly due to fall on outstretched hand or elbow
Posterior dislocation most common resulting in force to unlock olecranon from the trochlea
Highest incidence: 10 – 20y and sports Posterior dislocation following hypextension, valgus
injuries stress, arm abduction and forearm supination
Anterior dislocation results from direct force to the
posterior forearm with elbow flexed

Clinical Evaluation
Patients present guarding the injured
extremity
- Gross deformation Treatment
- Swelling Posterior dislocation
- Careful NV exam and repeat after - Closed reduction under sedation
reduction - Reduction performed with the elbow flexed while
- Associated injuries: coronoid providing distal traction
process fractures and - Post reduction management: posterior splint with
medial/lateral epicondylar elbow at 90 degrees
fractures Anterior dislocation
- Closed reduction under sedation
Radiographic Evaluation - Distal traction to the flexed forearm followed by
- AP and lateral elbow films should dorsally direct pressure on the volar forearm w
be obtained both pre and post anterior pressure on the humerus
reduction
- Careful examination for
associated fractures
Treatment
Nonoperative
Simple vs Complex - Closed reduction and splinting at least 90 degrees
for 5 – 10 days
Simple - Indicated in: acute simple stable dislocations
- Elbow dislocation w no
associated fracture Operative
- 50 – 60% cases - ORIF (coronoid, radial head, olecranon), LCL
Complex repair +/- MCL repair
- Elbow dislocation w associated - Indicated in: acute complex elbow dislocations,
fracture persistent instability after reduction, closed
Terrible triad reduction can’t be performed, entrapped soft tissue
1. LUCL tear or osteochondral fragments
2. Radial head fracture
3. Coronoid tip fracture

Radial head fractures in 10% of elbow

dislocations
Complications

Early stiffness
- Loss of terminal extension most common complication
- Early, active ROM helps prevent this

Varus posteromedial instability

- Injury to LCL and fracture of the anteromedial facet of the coronoid
- Solid fixation of the anteromedial facet is critical to prevent arthrosis

Neurovascular Injuries
- Brachial artery injuries (rare): associated w open dislocations
- Ulnar nerve injury: results from stretch
- Median nerve injury (rare): associated w brachial artery injuries

Recurrent instability
Heterotopic Ossification
- May require excision to improve elbow ROM

Dislocations in children are unusual but are generally related to: major trauma and associated with
fractures
- Ligaments in children are more elastic and stronger than bony structures

Subluxation of the Radial Head

- Occurs in toddlers due to a sudden pull on outstretched arm
- Traction causes radius to tear and partially slip through annular ligament and become trapped
below capitellum
Treatment
- Forced supination with elbow flexed, applying both traction and pressure to the elbow
- Successful reduction is accompanied by a “click” and mobility is restored
- Once elbow back in place = child uses it within minutes