Radiological results of Charnley total hip
Between 1976 and 1993, 164 total hip arthroplasties (THA) were performed on 130 patients at Kawasaki Medical School Hospital. Among these, we investigated 44 cases of Charnley low-friction arthroplasty(35 patients) for which a minimum 15- year follow-up was possible, with a focus on radiographical evaluation. The average patient age at surgery was 59.8 years (42.0-72.0). Our study surveyed seven items: the 15-year cumulative survival rate of implants, preoperative assessment of bone bed quality at the implant site, the location of implant placement, the condition of cement filling immediately after surgery and its changes over time, stem settlement, the presence or absence of a pseudoarthrosis at the greater trochanter, and polyethylene socket wear. The 15-year cumulative survival rate was 70.8% for sockets and 76.4% for stems, with loosening regarded as the endpoint. No significant differences in the final results were observed as a result of bone bed quality at the implant site or the location of implant placement. The implant survival rate was significantly higher for patients with good cement filling immediately following surgery compared with those with poor cement filling, and tended to be lower when stem settlement was present, strongly suggesting that the cement filling technique is important in the long-term results of THA. When a pseudoarthrosis of the greater trochanter was present, the survival curve declined rapidly from the immediate postoperative period, implying a negative influence on the implant survival rate. When implant loosening or osteolysis around the implant was present, there was a tendency for socket wear to increase, with the amount of polyethylene debris regarded as having a notable effect on bone bed weakening. (Accepted on January 12, 2010)
