gms | German Medical Science

Objectives: Evaluation of total hip arthroplasty results clinically and radiologically in cases with developmental hip dysplasia.

Methods: Between March 2007 and June 2011, total hip arthroplasties (THA) were performed in 113 hips of 94 patients with a mean age of 42 years diagnosed with Crowe Type II, III or IV developmental hip dysplasia (DHD) retrospectively evaluated. Mean postoperative follow-up was 55 months (range, 48-90 months). Pre and postoperative functional evaluations were made utilizing the Harris Hip Score (HHS). For radiological evaluation, pre and postoperative A-P pelvis and full-length radiographs were taken and limb length discrepancy, hip dysplasia by the Crowe classification, center of hip rotation by the Ranawat Method were identified. In cases where femoral shortening was required, a subtrochanteric oblique osteotomy was performed. In all hips, care was taken to achieve soft tissue balance. For evaluation of acetabular and femoral osteolysis, the Charnley and De-Lee, Gruen techniques were used respectively.

Results and Conclusion: Pre and postoperative mean HHS were 40 (30-54) and 90 (75-100) respectively. Mean limb length discrepancy was 30 mm (2-65) preoperatively and <10 mm postoperatively. Subtrochanteric oblique shortening osteotomy was performed on 48 (51%) of the hips. In all hips the acetabular component was placed in the true acetabulum. Graft was not required for component coverage in any hip. Ceramic-ceramic surfaces were used as the joint surface. Cotiloplasty was applied to 79 (84%) hips. None of the cases developed infection or dislocation. At the final follow-up osteolysis was not determined in any of the cases. In one case, a revision surgery was carried out for acetabular fracture resulting from a fall in the early period.

For anatomic placement of the acetabulum and sufficient coverage of acetabular component, rather smaller components were chosen, moreover the femoral heads were used for grafting and a controlled fracture in the medial wall of the acetabulum was performed. Femoral shortening osteotomy was the most used technique for rotational stability, lowering of the hip to anatomic location and prevention of the complications associated with vessel and nerve tension. Although there are studies in literature reporting good results with the application of a moderately high hip center in the treatment of these cases; the anatomic placement of the acetabular component in the THA, the eradication of limb length discrepancy and the assurance of soft tissue balance are extremely important to obtain successful results.