Epiphysiodesis of the greater trochanter in Legg-Calvé-Perthes disease: The importance of timing.

Patients with Legg-Calvé-Perthes disease (LCP) often exhibit relative overgrowth of the greater trochanter and shortening of the femoral neck. Biomechanically, this corresponds to a shorter lever arm and a decreased muscle tension which may result in a Trendelenburg gait and pelvic instability. This is a retrospective study of 31 patients (32 hips) with LCP disease and relative overgrowth of the greater trochanter who were treated with an epiphyseodesis. The average age at operation was 10 years and 6 months. We evaluated the patients clinically with the Trendelenburg sign and analysed on radiographs the growth of the greater trochanter and the neck-shaft angle of the normal hip and the pre- and postoperative growth and angle of the involved hip. We did not find any significant differences between the pre- and postoperative values. After a mean follow-up of 4 years and 2 months, however, 27 patients presented with a negative Trendelenburg sign (versus 14 patients preoperatively).