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How To Reduce a Posterior Hip Dislocation


Matthew J. Streitz

, MD, San Antonio Uniformed Services Health Education Consortium

Last full review/revision Dec 2019| Content last modified Dec 2019
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Most hip dislocations are posterior. A variety of closed reduction techniques all use traction-countertraction plus back-and-forth internal and external rotations of the femur. Procedural sedation and anesthesia (PSA) is required and may be insufficient.


  • Posterior dislocation of the hip

Reduction should be attempted as soon as possible after the diagnosis is made. A neurovascular deficit warrants immediate reduction.

Open dislocations require surgery, but closed reduction techniques should be used as interim treatment if an orthopedic surgeon is unavailable and a neurovascular deficit is present.

Posterior hip dislocations often occur as part of high-energy trauma events (eg, motor vehicle accidents) that can cause multiple injuries. Evaluation and treatment of cardiopulmonary status and diagnosis of life-threatening injuries are the first priorities.


Relative contraindications:

  • Associated fractures or other injuries to the hip

These require orthopedic consultation and possible open exploration and reduction by the orthopedic surgeon.


  • Sciatic nerve injury

  • Avascular necrosis of the femoral head. This can occur even with prompt reduction; however, the risk increases as time to reduction increases, particularly with times longer than 6 hours

Complications are usually the result of the dislocation itself.


  • Materials and personnel required for procedural sedation and analgesia (PSA)

  • Bedsheets

One to three assistants are needed.

Relevant Anatomy

  • The sciatic nerve lies posterior to the hip joint and may be injured during a posterior hip dislocation.


  • Position the patient supine on the stretcher.

  • Stand next to the affected hip.

  • Have an assistant stand at waist level on the unaffected side.

Step-by-Step Description of Procedure

  • Give procedural sedation and analgesia (PSA).

  • Flex both the hip and the knee 90° and maintain these flexions throughout the procedure.

Do one of the following techniques:

  • Allis technique:

    Place both of your hands about the affected proximal tibia.

    To apply axial traction, pull upward near the crux of the knee. Standing on the stretcher can help maximize leverage.

  • Captain Morgan technique:

    Flex your hip and knee, place your foot on the stretcher inferior to the affected buttocks (you may need to lower the stretcher), and place the affected knee over your knee (your knee will serve as a fulcrum). Avoid damaging the popliteal fossa tissues by positioning your knee just distal to the fossa, under the proximal calf.

    To apply axial traction, plantarflex your foot and pull the affected ankle downward.

  • Whistler technique:

    Place the patient supine with both knees flexed to 130°. Place one of your arms under the affected knee and grasp the unaffected knee. Your arm will serve as a lever. With your other hand, hold the affected ankle to anchor it to the bed.

    To apply axial traction, raise your shoulder to elevate the affected knee while keeping the affected ankle and foot firmly against the bed.

  • Rocket launcher technique:

    Face caudad and place the affected knee over your shoulder (your shoulder will serve as a fulcrum).

    To apply axial traction, press the affected knee inward and the foot outward. Then raise your shoulder and pull downward on the affected ankle.

With each technique:

  • Have the first assistant apply manual downward pressure on both iliac spines (countertraction to the hips), fasten the patient to the stretcher, or both.

  • Maintain and gradually increase the hip traction throughout the procedure.

  • Begin and maintain gentle rotation of the femur back-and-forth, internally and externally (ie, slowly wag the foot laterally and medially).

  • If reduction does not occur, have a second assistant, using arms or a sheet, apply lateral traction to the proximal thigh.

  • If reduction does not occur, gently adduct the femur maximally, and have a third assistant push down on the affected iliac spine with one hand while maneuvering the femoral head into the acetabulum with the other hand.

  • Successful reduction may be accompanied by a perceptible “clunk.”


  • Do a post-procedure neurovascular examination. A post-procedure neurovascular deficit warrants emergent orthopedic evaluation.

  • Do post-procedure x-rays to confirm proper reduction and identify any coexisting fractures.

  • Immobilize the legs in slight abduction by placing an abduction pillow between the knees.

  • Do a CT scan to identify acetabular or femoral head fractures and evaluate for intra-articular debris.

  • Refer the patient to the orthopedic surgeon; patients will usually be hospitalized.

Tips and Tricks


  • Hendey GW, Avila A: The Captain Morgan technique for the reduction of the dislocated hip. Ann Emerg Med 58 (6):536–540, 2011. doi: 10.1016/j.annemergmed.2011.07.010.

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