Application of subtrochanteric shortening osteotomy in total hip arthroplasty for Crowe type IV developmental dysplasia of the hip

Abstract

Objective To observe the effect of transveme subtrochanteric femoral shortening osteoto-my in total hip arthroplasty (THA) for Crowe type Ⅳ developmental dysplasia of the hip (DDH). Methods From February 2001 to February 2007, 12 patients with Crowe type Ⅳ DDH were performed primary THA combined with transverse subtrochanteric femoral shortening osteotomy. There were 3 males and 9 females,with the average age of 54 years(ranged, 45-65 years). Five hips were left, 7 hips were right and both sides for 1 patient. The average leg length discrepancy were 3.5 cm (ranged, 1.8-5.0 cm). There were 4 patients with moderate limp and 8 patients with servere limp. Clinical and radiographic data were retrospectively re-viewed at the 3rd, 6th, 12th month after operation, and then it was done every year. The bone union, pros-thesis subsidence, leg limp and the hip Harris score were evaluated. Results The average follow-up was 3.0 years (2-7 years), and the average length of shortening osteotomy was 2.2 cm (1.5-4.2 cm). No nerve injury and nonunion occurred. At ther final follow-up, there were 3 cases of mild limp, 4 cases of moderate limp and no severe ones. The mean Harris score improved from 36 (30-60) before operation to 83 (75-95). The mean union time was 5.3 months after operation (3-24 months after operation). The prosthesis subsidences were found in 1 case at the 5th year after operation and 1 case at the 7th year after operation, and with the subsiding height of 3 mm and 6 mm respectively. No loosening and infection were found in all patients.Conclusion Transverse subtrochanteric shortening osteotomy for Crowe type Ⅳ DDH is easy to performe. It can help to expose the true actabulum and fix the socket precisely, and also facilitate to improve the diame-ter of the prosthesis, correct the anterversion, and prevent nerve injury. Key words: Hip dislocation; congenital; Arthroplasty; replacement; hip; Osteotomy