Guided growth of the trochanteric apophysis combined with soft tissue release for Legg–Calve–Perthes disease

During the initial fragmentation stage of Perthes disease, the principle focus is to achieve containment of the femoral head within the acetabulum. Whether by bracing, abduction casts, femoral and/or pelvic osteotomy, the goals are to maximize the range of hip motion and to avoid incongruity, hoping to avert subsequent femoro-acetabular impingement or hinge abduction. A more subtle and insidious manifestation of the disease relates to growth disturbance involving the femoral neck. We have chosen to tether the greater trochanteric physis, combined with a medial soft tissue release, as part of our non-osteotomy management strategy for select children with progressive symptomatology and related radiographic changes. In addition to providing containment, we feel that this strategy addresses potential long-range issues pertaining to limb length and abductor mechanics, while avoiding iatrogenic varus deformity caused by osteotomy. This is a retrospective review of 12 patients (nine boys, three girls), average age 7.3 years old (range 5.3-9.7), who underwent non-osteotomy surgery for Perthes disease. An eight-plate was applied to the greater trochanteric apophysis at the time of arthrogram, open adductor and iliopsoas tenotomy, and Petrie cast application. We compared clinical and radiographic findings at the outset to those at an average follow-up of 49 months (range 14-78 months). Six plates were subsequently removed; the others remain in situ. Eleven of twelve patients experienced improvement in pain, and alleviation of limp and Trendelenburg sign at latest follow-up. The majority had improved or maintained range of motion and prevention of trochanteric impingement demonstrated by near normalization of abduction. Neck-shaft angles, Shenton's line, extrusion index, center edge angles and trochanteric height did not change significantly. One patient underwent subsequent trochanteric distalization and no other patients have undergone subsequent femoral or periacetabular osteotomies. Leg length discrepancy worsened in four patients and was treated with contralateral eight-plate distal femoral epiphysiodesis. As a group the mean leg length discrepancy did not change significantly. There were no perioperative complications. six trochanteric plates were subsequently removed after an average of 43.7 months (range 28-69) due to irritation of hardware; the others remain in situ, pending further growth. We employed open adductor and iliopsoas tenotomy and Petrie cast application and guided growth of the greater trochanter as a means of redirecting the growth of the common proximal femoral chondroepiphysis. The accrued benefits of preventing relative trochanteric overgrowth with a flexible tether are the avoidance of iatrogenic varus and weakening of the hip abductors. The goals are to preserve abductor strength and avoid trochanteric transfer or intertrochanteric osteotomy.