The hip joint consists of the acetabulum and the femoral head. The hip joint bony and the supporting ligaments provides stability. Injury and fractures of the hip joint implies breakage of these related structures. Hip dislocations, especially with associated fractures, are high energy fractures with significant soft tissue injury and require patient stabilization management according the the ATLS principles. Posterior hip dislocation is the commonest type.

Anatomic classification:

• Anterior
• Inferior (obturator)
• Superior (pubic)
• Posterior

Causes:

High impact axial loading to the hip joint ± intra-articular fracture:

• Falling on hip joint from elevated position
• Motor vehicle accidents

Presentation:

• Pain
• Swelling
• Deformity
• Inability to walk

Clinical Assessment:

• Bone tenderness
• Deformity
• Assess entire limb for ipsilateral limb injuries
• Exclude neurovascular limb injury and compartment syndrome
• Leg position with posterior dislocation: flexion, adduction and internal rotation
• Leg position with anterior dislocation: abduction and external rotation

Associated Injuries:

• Posterior acetabulum wall fractures
• Femoral head fractures
• Sciatic nerve injury
• Knee injuries

Posterior hip dislocation with associated femoral head fracture

Hip position with anterior and posterior dislocations

Type Ⅰ: dislocation with no or minor fracture

Type Ⅱ: dislocation with single large fragment of posterior wall

Type Ⅲ: dislocation with comminuted posterior wall

Type Ⅳ:  dislocation with fracture through acetabular floor

Type Ⅴ: dislocation with fracture through acetabular floor and femoral head

Type ⅠA: Superior dislocation, no associated fracture

Type ⅠB: Superior dislocation, associated fracture or impaction of femoral head

Type ⅠC: Superior dislocation, associated acetabulum fracture

Type ⅡA : Inferior dislocation, including obturator and perineal

Type ⅡB: Inferior dislocation, associated fracture or impaction of femoral head

Type ⅡC: Inferior dislocation, associated acetabulum fracture

X-rays:

• • AP pelvis
  • Hip X-rays
  • Additional: pelvis inlet/outlet and Judet views
  • X-ray additional anatomical areas where clinically indicated

CT: useful to assess hip position and associated hip fractures and for preoperative planning

Non-operative:

• Closed Hip reduction
• Post reduction X-rays and CT scan

Surgery:

Surgery indications:

• Irreducible hip dislocation
• Incongruent hip after closed reduction
• Associated femur/ acetabulum fractures

Surgery Approach for irreducible hip dislocation:

• Posterior: Kocher-Langenbeck
• Anterior: Smith-Petersen

Surgery Options:

• ORIF for acetabulum fracture: Plate & screw fixation
• Screw fixation for femoral head/neck fractures
• Arthroscopic hip surgery management in selected cases
• Post hip arthroplasty dislocation: manage abnormal implant position with revision hip arthroplasty surgery

Physiotherapy modality principles:

• Reduce pain and inflammation
• Regain ROM
• Gait re-education

Left hip dislocation reduction technique:

• Assistant stabilize hip at Anterior Superior Iliac Spine
• Gently flex hip to 90° and apply progressive increasing leg traction to leg with gentle adduction and hip internal rotation
• Reduction often felt
• Post reduction pelvic X-rays

• No hip flexion > 60°
• Early mobilization with partial weight bearing for 4-6 weeks
• Follow up after 3 months and assess for femoral head AVN

• Recurrent dislocation
• Sciatic nerve injury
• AVN of femur head
• Post traumatic arthritis

Kocher-Langenbeck approach

• Subcutaneous incision gluteus maximus and iliotibial band
• Deep dissection: expose short external rotators by removing overlying fat covering (Sciatic nerve lies posterior to the gemelli & internal obturator muscles)
• Detach gluteus maximus 1cm from the greater tuberosity insertion
• Detach the external rotators and apply a stay suture in the piriformis tendon 1cm lateral to its insertion attachment point

Kocher-Langenbeck approach

Reduce fracture

ORIF plate and screw fixation

Hip arthroscopy to manage associated hip dislocation injuries including labral tears