OXIDIZED ZIRCONIUM-NIOBIUM (OXINIUM) BALL HEAD: SYSTEMATIC REVIEW AND CASE REPORT OF LOCAL AND SYSTEMIC REACTIONS TO CATASTROPHIC FAILURE

Total hip arthroplasty is a very common procedure. The research for low wear bearings is still on. Surface-Oxidized Zirconium-Niobium Alloy (OxZr) is one of the materials born with this goal. We report the case of an OxZr femoral head undergoing rapid in situ wear following the dislocation of the polyethylene liner and direct contact with the metal back. Slow progressive pain, pseudotumor and limping were progressively observed. Histologically, only a fibrous reaction containing metal debris without relevant features of inflammation was observed. Nevertheless, OxZr debris evocated a slow scarce cellular inflammatory reaction and no systemic toxicity, as also reported in the literature. In case of repeated dislocations or suspected breakage of the liner, we recommend close follow-up and prompt revision.