Evolution of surgical techniques for the treatment of angular and torsional deviation in DDH: 20 years experience.

The anatomical abnormalities associated with developmental dysplasia of the hip (DDH) increase the complexity of hip arthroplasty. In addition, previous femoral osteotomy can deform the proximal femur. Noncemented cups and stems are specifically designed for dysplasia to recover the true acetabular region in Crowe grade IV and sometimes Crowe grade III; additional surgical procedures are required. The purpose of the study was to analyse the surgical procedure and then the reconstructive options in DDH. From 1984 until now, total arthroplasty has been performed, on dysplastic hips, in 2,101 patients for 2,308 hips (207 patients bilateral 9% rate). All the procedures were performed by the senior authors (LS, GG) at the same hospital specialised in elective hip surgery. More than 80% of patients came from Northern Italy. The average age was 51 (range 32-83), 565 cases had involved a previous femoral osteotomy. Out of these 2,308 cases, 128 cases needed treatment for corrections of femoral side deformity; 64 cases were subjected to a greater trochanter osteotomy. In 12 cases, proximal femur shortening was involved. In 9 cases, rotational abnormality and shortening were controlled with a distal femur osteotomy. Fifty-five cases were treated by a shortening subtrochanteric osteotomy that allows corrections of any deformity. Only noncemented stems were used. Long-term results in these patients are consistently inferior (70% survival rate at 15 years) compared to those in the non-DDH population (97.7% survival at 15 years). On the femoral side, early failures are the reflection of a learning curve and are due to insufficient fixation of the osteotomy. The more promising outcomes are those involving a shortening subtrochanteric osteotomy.