Trochanteric advancement for premature arrest of the femoral-head growth plate. 6-year review of 30 hips

Does trochanteric transfer eliminate the Trendelenburg sign in adults?

BACKGROUND

Premature closure of the proximal femoral growth plate results in coxa brevis, which usually is associated with insufficiency of the hip abductors. Distal and lateral transfer of the greater trochanter sometimes is recommended to correct this problem. Most of what is known arises from studies of children and adolescents.

QUESTIONS/PURPOSES

We asked whether this procedure in adults with coxa brevis would eliminate hip abductor insufficiency and would improve their hip function based on the Harris hip score (HHS).

PATIENTS AND METHODS

We prospectively followed 11 patients, aged 19 to 55 years (mean, 40 years) who had distal and lateral trochanteric transfer. All patients had pain and a positive Trendelenburg test before surgery. This test was performed at the latest followup by three observers and the interobserver reliability was determined by the kappa coefficient. The HHS was obtained before surgery and at the latest followup. The minimum followup was 25 months (mean, 52 months; range, 25-77 months).

RESULTS

Insufficiency of the hip abductors was eliminated in seven (according to two observers) and eight (according to one observer) of the 11 patients after surgery; the kappa coefficient ranged from 0.79 to 1.0. The mean HHS improved from 64 points preoperatively to 76 points at the final followup. The two patients with preexisting severe osteoarthritis of the hip had the worst final scores and persisted with a positive Trendelenburg test at the final followup.

CONCLUSIONS

Distal and lateral transfer of the greater trochanter can eliminate insufficiency of the hip abductors and improve joint function in adult patients with coxa brevis and we believe should be considered for patients without severe osteoarthritis of the hip.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Trochanteric advancement in patients with Legg-Calvé-Perthes disease does not improve pain or limp

Premature closure of the proximal epiphysis in patients with Legg-Calvé-Perthes disease can cause overgrowth of the greater trochanter. We asked whether distal transfer of the greater trochanter relieved pain and improved limp and whether the operation changed frontal plane kinematic and kinetic parameters of the hip and pelvis in the gait analysis. We reviewed 15 patients (15 hips) with an average age of 16.9 years (range, 13-26 years) who had the operation and were followed for a minimum of 28 months (average, 42 months; range, 28-54 months). The Iowa hip score increased from 85.0 (range, 75.5-87.0) before surgery to 89.1 (range, 83.0-97.0) at the final followup. Only three patients had no pain and Trendelenburg sign postoperatively. Pelvic obliquity angle of affected and contralateral normal hips in ipsilateral stance and contralateral swing phases remained unchanged after surgery. Hip adduction angle and abductor moment during single stance phase of affected and contralateral normal hips were not changed. We concluded trochanteric advancement does little to relieve pain and improve limp in patients with relative overgrowth of the greater trochanter and Legg-Calvé-Perthes disease.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Greater trochanteric transfer for the treatment of coxa brevis

We reviewed the outcomes of 28 patients for whom we did greater trochanteric transfer. Twenty-two (79%) patients treated for coxa brevis by greater trochanteric transfer had good relief of pain and limp. Four (1%) outcomes were fair and two (0.7%) were poor. Our outcomes compared favorably with those already reported in the literature. Patients who had avascular necrosis caused by Perthes disease tended to have a better outcome than those caused as a complication of treatment for hip dysplasia. A computer model based on radiographic measurements was useful in planning the placement of the transfer for biomechanical efficiency. The surgical technique and osteotomy planning is described. Our goal is to review (1) the effectiveness of our surgical procedure, (2) whether deformity etiology influences outcome, (3) the best way to achieve optimal biomechanical efficiency, and (4) how software assisted planning can assist in surgical planning.

Biomechanical study of various greater trochanter positions

A mathematical model was used in order to evaluate the mechanical situation after lateral, medial, distal and proximal displacements of the greater trochanter. It was calculated that lateral displacement may considerably reduce the hip joint contact force, while medial displacement greatly increases it. The influence of proximalization and distalization is much less pronounced. It was further shown that, regarding the postoperative relative hip abductor muscle strength, lateral and distal displacements of the greater trochanter are favourable, while proximal and medial displacements are not.