A comparative study between McKee-Farrar and Charnley arthroplasty with long-term follow-up periods.

One hundred seventy-seven consecutive total hip arthroplasties on 169 patients, 107 with a McKee-Farrar prosthesis and 70 with a Charnley low-friction arthroplasty, were followed in a prospective study. Fifty-five patients (31%) representing 55 hips died during the study period. Four (2%), two McKee-Farrar and two Charnley, were lost to follow-up study. The remaining 55 McKee-Farrar and 41 Charnley hips were evaluated after a mean follow-up period of 11.5 years (range, 10.1-13.5 years). Twenty-two (12%) of the hips had been revised. A survival study was performed and the two techniques were compared with regard to walking ability, Harris hip score, and radiologic assessment. No major differences were observed. The mean annual revision rate in this series was 1.3%. Walking distance increased from 200 m before operation to 2,000 m 1 year after operation and then remained constant during the observation time. The results, using the Harris hip score, were good or excellent (greater than 80 points) in 47%. Thirty hips (32%) showed signs of prosthetic loosening; 17 of these caused pain on weightbearing occasionally or regularly and 13 caused no pain at all.