抄録
Studies on implant fixation have shown that hydroxyapatite (HA) coatings provide early and strong fixation to bone. This is a report of 3 4 consecutive cases of total hip arthroplasties using implants in which titanium femoral components had a proximal HA coating, usually with an HA-coated hemispherical cup. The operations were mainly for osteoarthrosis, rheumatoid arthritis, or avascular necrosis.The average follow-up period was twenty-six months. The average JOA hip score was 8 5 points after one year and 8 5 points after two years. The incidence of pain had been low immediately after surgery and was 3 % after one year. Roentogenographic examination showed a rapid integration of implants with bone apposition on the coating surface within six months. No radiolucent line formation was detected around HA-coated implant parts, and there were no revisions for loose implants. Thus implant fixation using HA coatings is a reliable procedure for good bony fixation and clinical results.