What is the recommended management for an acute hip dislocation?

Management of Acute Hip Dislocation

Acute hip dislocation requires emergent closed reduction within 6 hours to minimize the risk of avascular necrosis, followed by immediate post-reduction imaging and early mobilization protocols unless contraindications exist. 1, 2

Immediate Reduction

• Perform closed reduction emergently in the emergency department using procedural sedation, as over 90% of dislocations can be successfully reduced without operative intervention 3, 4
• Time to reduction is the primary determinant of both short and long-term outcomes, with delayed reduction significantly increasing avascular necrosis risk 2
• For posterior dislocations (most common type), apply longitudinal traction with internal rotation while the patient is supine 4
• For anterior dislocations, use inline traction with external rotation, with an assistant pushing on the femoral head or pulling the femur laterally 4
• Consider the Captain Morgan technique as a primary method: place your knee behind the patient's flexed knee and lift with anterior force, with rotation as needed—this has a 92% success rate and avoids the need for multiple assistants 5

Post-Reduction Imaging Protocol

• Obtain pelvic radiographs immediately after reduction to confirm concentric reduction and detect associated fractures or intra-articular fragments 1
• Proceed to non-contrast CT scan of the hip if you identify posterior acetabular wall fractures on radiographs, if closed reduction failed, or if radiographs show joint incongruity 1
• CT has 87.3% sensitivity for detecting intra-articular fragments, though small fragments may still be missed in up to 43.3% of cases 1
• Do not routinely order bone scintigraphy, contrast-enhanced CT, or contrast-enhanced MRI for post-reduction follow-up 1
• Reserve non-contrast MRI only for suspected abductor tendon, muscle, or ligament injuries that may compromise stability 1

Critical Pitfall: Ipsilateral Knee Evaluation

• Systematically evaluate the ipsilateral knee in all hip dislocation cases, as hip dislocation increases the risk of knee injury 7-fold (OR 7.25) 6
• Posterior cruciate ligament (PCL) injury is most common (41.2% of knee injuries), followed by meniscal injury (17.6%) and tibial plateau fractures (23.5%) 6
• Obtain knee MRI when clinically indicated, as tibial plateau fractures may not be visible on plain radiographs and delayed recognition leads to secondary meniscal and chondral damage 6

Mobilization Protocol

Early mobilization is the standard approach unless specific contraindications exist:

• Begin relative rest for 3-9 days with multimodal analgesia, considering nerve blocks to facilitate early mobilization 1
• Progress to partial weight-bearing at an average of 9 days, advancing to full weight-bearing at 3 months 1
• Early mobilization reduces complications from prolonged immobility, allows faster return to work, and does not increase early complications compared to prolonged traction 1
• Avoid excessive hip flexion and internal rotation to prevent redislocation 1

Contraindications to Early Mobilization

Do not mobilize early if:

• Unstable acetabular fractures requiring surgical fixation are present 1
• Post-reduction imaging shows non-concentric reduction 1
• Large intra-articular fragments prevent stable reduction 1

Surgical Considerations

• If closed reduction fails or contraindications to early mobilization exist, proceed to arthroscopy or open reduction with potential fracture fixation and soft-tissue repair 2
• For chronic dislocations with ligamentous tears and cartilage destruction, total hip replacement becomes the definitive treatment, with 43-84% pain-free outcomes at 9.4-year follow-up 7