In a prospective study of 100 consecutive Wagner resurfacing hip
arthroplasties in ninety-three patients, the outcomes for all hips were
determined for an eight to ten-year follow-up period. By survivorship
analysis, the rate of survival of the arthroplasty was calculated to be 70
per cent at five years, but only 40 per cent at eight years. The major
cause of failure was aseptic loosening of the acetabular or femoral
component, or both. Fracture of the neck of the femur occurred in three
hips. Although the medium-term results (at fifty-six to eighty-three
months) were better than those in most comparable studies of resurfacing
arthroplasty, the poor long-term results (at ninety-one to 118 months) show
that meaningful studies of new prosthetic designs must continue for at
least eight years, and, if at all possible, must include 100 per cent
follow-up. The survival curve for the resurfacing arthroplasties in this
study can serve as the basis for comparison of the early, medium, and
long-term results of future designs of resurfacing hip prostheses.