RANDOMIZED STUDIES OF RECONSTRUCTIVE ARTHROPLASTY IN THE ANATOMICALLY DIFFICULT HIP

Abstract

Sixty primary hip arthroplasties were performed in Crowe grade 2 to 4 hip dysplasia since 1973 using a modified transtrochanteric osteotomy which is reliable short cut to reach down the lateral aspect of the greater trochanter. Our hypothesis consists of the adaptability of Thomas test to show the reducibility of the disloction in the coronal plane. In practice, if the dynamic potential while abduction and flexion exceeds from the 90° to coronal plane, the femoral head slips down to the acetabulum through poor sciatic notch. Thereby led to Protrusio acetabulii which implicative compromised capsular insufficiency but assessment of outcome study has been improved.

The results have been reasonably acceptable, with the longest follow-up greater than 35 years. We confirmed that the frog leg lateral radiography is effective for determining the operative indication of high riding dislocation of the DDH. However irreducible frog leg lateral position is absolutely contraindicated in these situation. We also aware of not only the complexity in abductor length but abundant amount of vastus lateralis when reattaching the trochanter, which may arises against stability of the abductors and vastus lateralis in continuity.