Retrieval Analysis of Femoral Zirconium Components in Total Knee Arthroplasty : Preliminary Results

Safety of oxidized zirconium (OxZr) in total knee arthroplasty (TKA) has been supported by biomechanical, clinical, and radiologic data. Retrieved OxZr femoral components and corresponding polyethylene (PE) inserts were examined to rule out patterns leading to early failure. Sixteen retrieved TKA with an OxZr femoral component were included. The PE inlays were analyzed applying an established scoring system for wear and surface damage. Femoral components were screened for scratching, pitting, delamination, and striations. The prostheses were in situ for 16.4 ± 11.9 months. The average wear and damage score for the tibial PE inserts was 36.0 ± 12.7. The average score in the visual analysis of the OxZr femoral components was 1.3 ± 1.3. The data presented in this study did not show major wear of the PE in TKA using OxZr components. In this cohort, there were no failures directly related to this implant.