Hip dislocation


  • Orthopedic emergency; reduction of native hips should occur within 6hr due to high risk of avascular necrosis
  • High-energy trauma is primary mechanism


  • Posterior
    • 90% of hip dislocations
    • Acetabular fractures may result as well
  • Anterior
    • 10% of hip dislocations[1]
    • Can be superior (pelvic) or inferior (obturator)
    • Neurovascular compromise is unusual

Clinical Features

  • Posterior Dislocation
    • Extremity is shortened, internally rotated, adducted
    • Often Knee-to-Dashboard
    • Assess neurovascular exam
      • Sciatic nerve is most common compromised
  • Anterior Dislocation
    • Extremity is extended (superior) or flexed (inferior), externally rotated, abducted[2]
    • Similar to hip fracture

Differential Diagnosis

Hip pain


Post-surgical hip dislocation
  • Hip AP and lateral views
    • Posterior Dislocation: AP view femoral head posterior and superior to acetabulum
    • Anterior Dislocation: AP view shows femoral head in obturator foramen (inferior to acetabulum)
    • If associated femoral neck fracture, will likely need orthopedics
  • Consider Judet views
  • Consider knee xray
  • Consider CT to evaluate acetabulum for subtle fractures (esp for posterior dislocation)



  • Allis Maneuver: supine patient on table: deeper sedation (propofol helps with tissue relaxation); firm distal traction at flexed knee to pull head back into acetabulum; assistant stabilizes pelvis by pushing on ASISs

Hip Reduction.jpg


  • Reduction: traction, internal rotation, and then external rotation once the femoral hip clears the acetabular rim

Captain Morgan Hip Reduction[4]

  • See figure here
  • See video here
  • Provider's knee behind supine patients flexed knee with anterior force lifting (via provider plantar flexing foot) and rotation as needed
  • Successful in patients with prosthetic hips as well
  • Poses less risk of knee injury since most force is applied by lifting leg rather than applying leverage at knee
  • Less risk to provider who does not have to stand on top of gurney, and requires only one provider


  • If reduced, outpatient with ortho follow up

Post Reduction Care

  • Maintain dislocation precautions:
    • Do not bend the operated hip past 90 degrees (use knee immobilizer as needed)
    • Do not cross the midline of the body with operated leg (use hip abduction pillow)
    • Do not rotate the operated leg inward
    • In bed, toes and knee cap should point toward ceiling
  • Toe touch weight bearing


  • Post-traumatic arthritis
    • 20% in simple dislocations
    • high in complex dislocations
  • Femoral head osteonecrosis
    • 5-40% incidence
    • Delay in treatment >6 hours can lead to avascular necrosis of the femoral head => osteonecrosis
  • Sciatic nerve injury
    • 8-20% incidence
    • associated with longer time to reduction
  • Recurrent dislocations: <2%



  1. Holt GE and McCarty EC. Anterior hip dislocation with an associated vascular injury requiring amputation. J Trauma. 2003; 55(1):135-138.
  2. Alonso JE, et al. A review of the treatment of hip dislocations associated with acetabular fractures. Clin Orthop Relat Res. 2000; 377(8):32-43.
  3. Jaskulka RA, et al. Dislocation and fracture-dislocation of the hip. J Bone Joint Surg Br. 1991; 73(3):465-469.
  4. Hendey GW and Avila AA. The Captain Morgan Technique for the Reduction of the Dislocated Hip. Annals of Emergency Medicine, Volume 60, Issue 1, July 2012, Pages 135-136.