Minimum five-year follow-up wear measurement of longevity highly cross-linked polyethylene cup against cobalt-chromium or zirconia heads

102 patients with hip OA, scheduled to undergo cementless THA, were randomized to receive 26 mm zirconia head or 26 mm Cobalt-Chromium head coupled with a highly cross linked polyethylene liner. At the mean follow up of 6.7 years after total hip arthroplasty, zirconia head coupled with highly cross-linked polyethylene was not shown to be statistically different in total penetration rate and steady-state wear rate compared to a cobalt-chromium head coupled with highly cross-linked polyethylene. No incidence of osteolysis was found in either group.