Surgical Hip Dislocation for the Treatment of Femoroacetabular Impingement and Slipped Capital Femoral Epiphysis



Surgical Hip Dislocation for the Treatment of Femoroacetabular Impingement and Slipped Capital Femoral Epiphysis


Young-Jo Kim

Rachel Yvonne Goldstein



Surgical hip dislocation is an approach that can be utilized in the treatment of a wide variety of hip pathologies in order to improve or restore normal acetabular and/or femoral head-neck anatomy. Treatment of hip pathology through this approach seeks to preserve hip motion, prevent impingement, and delay or avoid early degenerative changes. This approach preserves the medial femoral circumflex artery (MFCA), the main blood supply to the femoral head, by maintaining intact external rotator muscles through the creation of a trochanteric flip osteotomy. Once performed, multiple procedures can safely be undertaken to address the specific pathology.




INDICATION/CONTRAINDICATIONS

Surgical dislocation is an approach to the hip that can safely be performed to treat a variety of intra- and extra-articular hip conditions.



  • Indications



    • Femoroacetabular impingement (FAI)


    • Extra-articular impingement


    • Labral tears


    • Chondral injuries


    • Femoral head-neck deformities



    • Fractures of the acetabulum, femoral head, or femoral neck


    • Tumors


    • Slipped capital femoral epiphysis (SCFE)


    • Post-Perthes deformities


  • Contraindications



    • Instability (may require a concomitant acetabular-sided procedure)


PREOPERATIVE PLANNING



  • Thorough history and physical examination is essential to identify the main source of symptoms.


  • Decreased femoral head-neck offset is best appreciated on:



    • The 45-degree Dunn lateral view of the hip


    • Radial reformats of CT or MR scans around the femoral neck axis


    • Three-dimensional reconstructions of a CT scan


  • Evaluation of a patient with SCFE requires AP and frog lateral views of the pelvis to evaluate slip severity.


  • After general anesthesia is administered, true hip flexion and hip rotation in both flexion and extension should be evaluated.




SURGICAL PROCEDURE



  • Patient positioning



    • The patient is placed in the full lateral position with the operative hip up (Fig. 20-1).


    • Secure the patient with a pegboard or lateral hip positioner. Care must be taken to ensure that positioners do not impede hip adduction, external rotation, or flexion.


    • A flat-top cushion with a half-moon-shaped cutout for the down leg is placed beneath the operative leg to stabilize the leg during the approach.


    • A hip drape with a sterile side bag is used to capture the leg during the dislocation maneuver. Alternatively, a sterile Mayo stand cover secured to the drapes may be utilized.


  • Approach



    • An anterior dislocation through a Kocher-Langenbeck or a Gibson approach with a trochanteric flip osteotomy



      • The Gibson approach



        • Proceeds between the gluteus medius and maximus muscles


        • Spares the abductors and gluteus maximus


        • Results in less hip extensor dysfunction


        • May make anterior exposure more difficult in patients who are obese or who have a very anterior border of the gluteus maximus


      • Kocher-Langenbeck approach



        • Splits the gluteus maximus muscle


        • Improves anterior exposure


  • Incision



    • A curved, longitudinal skin incision is made, centered over the junction between the anterior and middle thirds of the greater trochanter.






      FIGURE 20-1 The surgical dislocation approach for the hip is performed in a full lateral position. A radiolucent table is preferred so that a fluoroscopic unit can be brought underneath the table into a full lateral position for an AP view of the hip.







      FIGURE 20-2 After the fascia lata is opened, the trochanteric branch of the medial circumflex artery is easily identified. This marks the level of the obturator externus (OE) tendon and border of the quadratus femoris muscle. The trochanteric osteotomy is performed in the posterior edge of the gluteus medius and the vastus tubercle.


    • Subcutaneous tissue and fat are incised down to the iliotibial band and fascia overlying gluteus maximus.


    • Identify anterior border of gluteus maximus, which is marked by perforating branches of superior gluteal artery that run within the thin fascia between the gluteus medius and maximus muscles and perforate the fascia lata overlying the maximus and medius.


    • Because the vessels are accompanied by branches of the inferior gluteal nerve for the anterior portion of the gluteus maximus, the fascia is kept with the gluteus maximus.


    • The fascia lata is split distally in line with the incision.


    • The anterior border of the gluteus maximus is palpated, and the fascial incision is carried proximally along this line, taking care to bring gluteus maximus posterior off of fascia.


    • The space between the maximus and medius is opened, and the posterior border of the medius is identified.


    • The bursa at the posterior border of the greater trochanter is identified and reflected anteriorly.


    • The trochanteric branch of the MFCA is visualized and coagulated (Fig. 20-2).


    • The hip is internally rotated 20 to 30 degrees, and the posterior border of the medius is identified. The border between the medius and the piriformis tendon is identified.


    • The proximal 4 to 5 cm of fascia of the vastus lateralis is incised, and the vastus muscle fibers are reflected anteriorly. Care is taken to stay superficial to the periosteum of the femur as the periosteum is contiguous with the hip capsule.


  • Trochanteric flip osteotomy

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Jun 13, 2016 | Posted by in ORTHOPEDIC | Comments Off on Surgical Hip Dislocation for the Treatment of Femoroacetabular Impingement and Slipped Capital Femoral Epiphysis

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