20-YEAR RESULTS OF MCKEE-FARRAR VERSUS CHARNLEY PROSTHESIS

The results of 107 consecutive McKee-Farrar and 70 Charnley total hip arthroplasties performed in 169 patients between 1975 and 1976 are rev iewed. At an average followup of 20 years (range, 19-21 years), 29 pat ients with 20 McKee-Farrar and 11 Charnley prostheses were available f or clinical and radiologic evaluation; 102 patients (107 hips) had die d, 3 patients were lost to followup, and 5 patients (6 hips) were unav ailable for review because of medical problems. There were 5 revisions for sepsis and 1 Girdlestone procedure for recurrent dislocation. Six teen McKee-Farrar and 8 Charnley prostheses were revised for aseptic l oosening, giving a 20-year aseptic probability of survival of 77% and 73%, respectively. Radiographic signs of loosening were present in 52% of the surviving prostheses. Clinical scores showed weak correlation with the radiographic loosening in both groups, and 18 McKee-Farrar an d 8 Charnley prostheses were still considered satisfactory by the pati ents. The mean annual linear polyethylene wear was 0.12 mm. Osteolytic lesions were observed in association with 2 McKee-Farrar and 5 Charnl ey prostheses in surviving hips. The long term results of the McKee-Fa rrar prosthesis are comparable with those of the low friction arthropl asty in this series. Wear of the polyethylene bearing and accumulation of polyethylene particles in the periprosthetic tissue may become an increasing problem. Second generation all metal implants seem to be wo rth considering in patients with long life expectancy.