Fifteen years' experience with Charnley low-friction arthroplasty.

In the years from 1973 to 1986, 359 low-friction hip arthroplasties were performed by the precise Charnley technique in 310 patients. Three hundred seventeen hips were reexamined both clinically and roentgenologically. Clinical evaluation was performed according to follow-up time, separating the total number of hips into three groups. In Group A, 78.49% of the reevaluated hips remained asymptomatic ten to 14 years postoperatively, a percentage that has risen to 92.02% in Group B (studied five to nine years postoperatively) and 98.38% in Group C (studied one to four years postoperatively). The infection rate was 9.6% in Group A hips, 4.7% in Group B hips, and inconsequential in Group C hips. The roentgenographic study included 96 asymptomatic hips with a follow-up period of six to 11 years (mean, 8.3%). A radiolucent line was present in the acetabulum in 40.6% of cases; cortical hypertrophy at the tip of the stem was present in 48.8% of cases. Cup wear of more than 1 mm was measured in 41.3% of hips and was correlated with longer follow-up times and younger patient age. The results are encouraging for the continuation of arthroplasty by this method.