Early failure of a roughened surface, precoated femoral component in totalhip arthroplasty

A retrospective study was performed of a consecutive series examining 98 pr imary hip arthroplasties between March 1992 and December 1995. A second-gen eration roughened surface (grit-blasted), polymethyl methacrylare-precoated femoral component (Centralign prosthesis, Zimmer. Inc, Warsaw, IN) was use d for all cases. Clinical and radiographic data were available for 84 hips (76 patients). The average duration of follow-up was 35.8 months. There wer e 10 failures by aseptic mechanical loosening of the femoral component (12% ) at an average 30.6 months postoperatively, 9 having been revised (11%). R evision was pending in the remaining patient. The average age of patients a t primary arthroplasty for the failed group was 48.2 years compared with 63 .4 years for the asymptomatic patients (P = .0008. In all cases, failures o ccurred by debonding of the femoral prosthesis from the cement mantle. We a re not aware of any series using modern implant components and cementing te chniques with an early mechanical failure rate of this magnitude.