ハイドロキシアパタイト顆粒をステム周囲に充填したセメントレスTHA

―リウマチ症例と非リウマチ症例との比較―

抄録

We evaluated the radiological changes after total hip arthroplasty using hydroxyapatite (HA) granules around the femoral components in 10 hip joints with rheumatoid arthritis and in 51 hips with osteoarthritis or femoral head necrosis. The average postoperative observation periods were 6.5 years and 6.4 years, respectively. We used HA granules, aiming to prevent micro-motion of the femoral component. As a result, loosening of the femoral stem was found in 10% of both groups. Bone atrophy at the greater trochanter was found in 80% of both groups, and the atrophy was thought to be a sign of stress shielding. The wear-rate of HDP was 0.18 millimeters per year, and that rate rate was identical with previous reports. We thought the use of HA granule around the femoral stem might reduce the incidence of loosening of the femoral stem, and use of HA granules might not increase the wear-rate of HDP, but the incidence of stress shielding might be increased with the use of HA granules.