Treatment of Coxa Profunda With Open Surgical Hip Dislocation, Rim Resection, Cam Resection, and Labral Reconstruction

Abstract

Coxa profunda presents a unique challenge in surgical treatment approach given global acetabular overcoverage. Arthroscopic treatment can be fraught with difficulty obtaining hip distraction for safe arthroscopic instrumentation, and limited arthroscopic access may prevent sufficient osseous resection of the excess acetabular rim. Although hip arthroscopy use has increased markedly over the past decades for all types of hip pathology, coxa profunda may represent one unique indication for surgical hip dislocation. This technique describes open surgical hip dislocation, rim resection, femoral osteoplasty, and labral reconstruction using anterior tibialis allograft for coxa profunda with combined-type femoroacetabular impingement syndrome and labral ossification.

Fig 1

Preoperative (A) standing AP pelvis, (B) modified 45° Dunn lateral, and (C) standing false profile radiographs show coxa profunda, defined as the acetabular fossa (asterisk) medial to the ilioischial line (dotted) with labral ossification (arrow). (A) Lateral center-edge angle (LCEA) measures 56° (dysplasia <20°, normal 20°-40°, overcoverage >40°). (B) Modified 45° Dunn lateral view shows alpha angle of 59° (normal <42°, cam deformity >50°-55°). (C) False profile radiograph shows anterior center edge (ACE) angle of 45° (normal >25°).

Fig 2

Patient is positioned lateral decubitus on a Jackson table with a bean bag. Peroneal nerve is padded on the down leg, and a blanket bridge is used between the legs to appropriately abduct.

Fig 3

With the patient in the lateral decubitus position, a modified Gibson approach to the hip is made. (A) The gMax is retracted posteriorly and the tensor fascia latae anteriorly with a Charnley retractor. This gives visualization of the vastus ridge and gMed. (B) The interval between the gMed and gMin is developed. (C) The gMin is sharply released to reveal the hip capsule with retraction of the piriformis. VR, vastus ridge; gMed gluteus medius; gMin, gluteus minimus; P, piriformis; Ca, capsule.

Fig 4

A trochanteric step-cut osteotomy is performed with the gMed tendon, long tendon of the gMin tendon, and vastus lateralis tendon attached to the mobile trochanter by making a cut along the posterior aspect of the greater trochanter starting just anterior to the most posterior fibers of the gMed. TO, trochanteric osteotomy; ST, stable trochanter; gMed, gluteus medius; VR, vastus ridge.

Fig 5

(A) The trochanteric osteotomy is retracted to put the remaining fibers of the gMed on tension and then allowing their sharp release. (B) The remaining gMed fibers are sharply elevated off the stable trochanter. (C) The gMin is sharply elevated from the hip capsule. TO, trochanteric osteotomy; ST, stable trochanter; gMed, gluteus medius; gMin, gluteus minimus; P, piriformis; Ca, Capsule.

Fig 6

The Z-capsulotomy performed in coxa profunda patients differs from a standard Z-capsulotomy in that it is raised subperiosteally off of the acetabular rim versus distal to the labrum in a standard Z-capsulotomy.

Fig 7

(A) The modified Z-capsulotomy is used to access the hip joint. (B) The piriformis is transected and tagged to complete the capsulotomy and allow greater access to the posterior wall. GT, greater trochanter.

Fig 8

(A) The native labrum is elevated sharply in a bucket-handle fashion. In this case, a majority of the labrum was ossified, so the native labrum was diminutive. (B) The amount of resection required is determined by using the osteotome under fluoroscopy to establish a normal center edge angle. (C) The acetabular rim is resected carefully using osteotome. Here is shown halfway through completion. If it is done with the hip reduced, a freer is used to protect the cartilage. It can also be done with the hip dislocated. (D) The rim resection is complete. The native labrum is left intact at the far anterior and posterior aspect. Ac, acetabulum; FH, femoral head; La, labrum.

Fig 9

(A) The femoral head can be gently dislocated with hip flexion and external rotation to visualize the cam lesion. (B) A 5 mm round burr is used to perform femoral osteoplasty until sphericity is achieved as confirmed by a femoral head sizer. FH, femoral head.

Fig 10

(A) The hip is reduced after anchors are placed along the rim of the acetabulum. The tabularized anterior tibialis allograft is secured in place with mattress stitches at the far anterior and posterior aspect with the hip reduced while incorporating the native labrum if present. (B) The allograft is secured with simple stitches including the native labrum if present through the midportion. The labral reconstruction should restore the suction seal of the hip. AT, anterior tibialis; FH, femoral head; Ac, acetabulum; La Recon, labral reconstruction.

Fig 11

A capsular closure of the modified Z-capsulotomy is complete with 0 PDS. The flaps of the capsule should lay onto the new acetabular rim where they will eventually heal to the exposed bone. Ca, capsule.

Fig 12

(A) The greater trochanteric osteotomy is reduced and held with k-wires. (B) Definitive fixation of the osteotomy with three 3.5 mm lag screws is confirmed with fluoroscopy.

Fig 13

Final intraoperative AP pelvis radiograph shows normal center edge angle, removal of ossified labrum, and trochanteric osteotomy fixation.