Combined acetabuloplasty and varus derotation osteotomy in congenital dislocation of the hip. Long-term results.

Twenty-two patients (33 hips) with congenital dislocation of the hip were examined at an average of 26 years after combined acetabuloplasty and intertrochanteric varus derotation osteotomy. Seventeen patients had no problems despite physically demanding jobs and sporting activities in some cases. The CE angle was improved to the lower end of the normal range. The shaft-neck angle was corrected by 31 degrees to 120 degrees. Restoration to the normal valgus subsequently occurred and we found no evidence of subcapital coxa valga. Although there was an increase in the neck epiphysis angle 5 years after operation indicating a horizontal shift in the epiphyseal plate, most cases had normal hip joints. The incidence of postoperative avascular necrosis of the femoral head was 6%, and we found no increase in femoral deformities. Our long-term results show that the combination of acetabuloplasty and femoral osteotomy has no disadvantages, and is the best way of achieving optimal centring of the femoral head and stabilisation of the hip.