ＲＡの臼底突出に対するＡｃｅｔａｂｕｌａｒ ｒｅｉｎｆｏｒｃｅｍｅｎｔ ｒｉｎｇ ｗｉｔｈ ｈｏｏｋ使用例の成績

Abstract

Between 1998 and 2001, we performed five primary total hip replacements in four rheumatoid arthritis patients (RA) using a Ganz acetabular reinforcement ring with hook and acetabular impaction grafting. The mean age of the four females and one male was 47.2 years (range : 28 to 62 years). The mean follow-up period was 3 years 8 months (range : 2 to 5 years). Partial weight-bearing was started one week after surgery. In spite of early weight-bearing, all grafts appeared to have united radiologically with no radiolucent lines between graft and acetabulum and no signs of collapse. None of these 5 rings showed any signs of material loosening radiologically. Clinical evaluation was performed according to the Japanese Orthopaedic Association (JOA) hip score system (JOA hip score, except ADL score). The mean JOA hip score improved, from 19.0 before the operation to 62.4 at the latest follow-up. The acetabular reinforcement ring may prevent graft resorption and cup migration, which are major causes of socket failure in protrusion acetabuli for RA.