Gluteus medius and minimus insertion advancement for correction of internal rotation gait in spastic cerebral palsy.

The gluteus medius and minimus muscles were transferred in twenty-six patients (forty-two hips) with spastic cerebral palsy. The transfer of the insertion of these muscles from the greater trochanter to the anterior part of the femur was done to change their function from that of inward rotators to that of outward rotators of the hip. In the follow-up period, ranging from three to eleven years, the transferred muscles functioned as outward rotators without sacrificing their abduction strength in 90 per cent of the patients. The failures were due primarily to lack of integrity of the transferred muscle insertion. No increase in valgus angulation of the femoral neck was recorded except when the integrity of the trochanteric apophysis had ben compromised. Additionally, in ten patients (thirteen hips) who were operated on when they were from five to eight years old and were followed to skeletal maturity, the angle of anteversion was reduced to at least 25 degrees (range, 18 to 36 degrees). This procedure is indicated in the patient with spastic cerebral palsy to correct an inward-rotation gait caused by hyperexcitable gluteus medius and minimus muscles. It has been useful in eliminating the problems of clumsiness on running and walking associated with tripping, falling, fatigability, and excessive shoe-wear without compromising the abduction power of the gluteus medius and minimus.