Rotational acetabular osteotomy for secondary osteoarthritis after surgery for developmental dysplasia of the hip

The treatment of residual deformity following surgery for developmental dysplasia of the hip remains controversial. The rationale for the use of the rotational acetabular osteotomy (RAO) is that it increases the weight-bearing area by shifting the osteotomized acetabulum to cover the femoral head. This can improve joint function as well as achieve relief of pain. However, it is unclear if this osteotomy can improve a compromised hip when performed for the treatment of residual deformity and acetabular dysplasia after surgery for developmental dysplasia of the hip. We aimed to report the clinical outcome as assessed by need for total hip arthroplasty (THA) and by the Merle d'Aubigné and Postel scores. In addition, we tried to assess the radiographic outcomes as assessed by Tönnis's classification. Only two hips required THA, which was performed in two patients at 11 and 12 years after RAO, respectively. The mean Merle d'Aubigné clinical score improved from 14.1 +/- 2.3 points (range, 10 to 17) preoperatively to 15.8 +/- 2.9 points (8 to 18) at final follow-up (p < 0.02). Radiological assessment at final follow-up showed the obvious progression of osteoarthritis in five hips. One patient in grade 1 preoperatively progressed into grade 3 at final follow-up; four patients in grade 2 preoperatively progressed into grade 3. In our study, this osteotomy prolonged the functional life of the hip, and only two hips needed THA after a mean follow-up of 11 years. We found that advanced arthritis pre-osteotomy is associated with progression of radiologic changes.