A modified periacetabular osteotomy with use of the transtrochanteric exposure

Background: Periacetabular osteotomies are technically demanding surgical procedures. We developed a modified technique that uses a transtrochanteric approach. Our goal was to facilitate surgical exposure without compromising the results of surgery. The purpose of the present study was to review the early results in our initial group of patients who had this procedure. Methods: We retrospectively reviewed the results of a modified periacetabular osteotomy in thirty-eight consecutive patients (forty-six hips) at an average duration of follow-up of 4.2 years. The average age of the patients was thirty-one years (range, eighteen to fifty-eight years) at the time of surgery. We evaluated the results with use of serial radiographs and the Merle d'Aubigne and Postel hip-scoring system. Results: All osteotomies healed. Preoperatively, the average lateral center-edge angle was 3degrees (range, -15degrees to 12degrees), the anterior center-edge angle was 0degrees (range, -20degrees to 5degrees), the acetabular angle of Sharp was 57degrees (range, 50degrees to 68degrees), and the femoral head coverage was 53% (range, 40% to 66%). Postoperatively, the average lateral center-edge angle was 35degrees (range, 23degrees to 45degrees), the anterior center-edge angle was 32degrees (range, 20degrees to 55degrees), the acetabular angle of Sharp was 40degrees (range, 37degrees to 45degrees), and the femoral head coverage was 92% (range, 85% to 100%). The average amount of medialization of the femoral head was 6 mm. At the latest follow-up examination, improvement in the grade of osteoarthritis was noted in eight hips, while progression of osteoarthritis was seen in five hips. Functionally, the average Merle d'Aubigne and Postel hip score improved from 13.2 points preoperatively to 17.0 points postoperatively. No patient had a neurovascular complication. Conclusion: Our early experience with a modified periacetabular osteotomy showed encouraging results in terms of the technical ease of the technique and the outcome in our patients. Level of Evidence: Therapeutic study, Level IV (case series [no, or historical, control group]). See Instructions to Authors for a complete description of levels of evidence.