Evaluation of Oxinium (Oxidized Zr2.5Nb) Femoral Heads in Hip Endoprostheses—Case Report

Total hip arthroplasty (THA) is a widely performed and successful surgical treatment for degenerative joint disease. With increasing use in younger and more active patients, the demand for durable, biocompatible, and low-wear implant materials has grown. Oxidized zirconium (Oxinium, Zr2.5Nb) was introduced as a promising femoral head material, combining the strength of metal with the low-friction properties of ceramic. Despite encouraging early results, clinical reports have documented complications including head wear, especially after dislocation, and metallosis. We present the case of a 64-year-old male who underwent primary THA in 2009 and required revision in 2021 due to severe metallosis. Notably, no dislocation was observed that could explain the damage to the Oxinium head. Surface and subsurface analyses using X-ray photoelectron spectroscopy (XPS) and micro-indentation hardness testing revealed wear and deformation inconsistent with Oxinium’s anticipated durability. These findings highlight the importance of the femoral head–polyethylene liner interface in implant longevity. Although Oxinium–XLPE articulations remain promising, risks such as damage to the femoral head, liner dislocation, impingement, and metallosis must be carefully considered. Surgical technique, liner placement, and locking mechanisms play critical roles in preventing failure. Further biomechanical and clinical studies are needed to optimize implant design and improve long-term outcomes.