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

The aim of our study was evaluation of the Oxinium Femoral Heads in Hip Endoprosthesis: Clinical Outcomes, Wear Characteristics, and Long-Term Performance. Orthopaedic patients suffering from joint pain due to arthritis or injury and total hip arthroplasty (THA) is a common and very successful surgical option. THA involves replacing the damaged femoral head and acetabulum with prosthetic components, typically composed of metal alloys, ceramics and polymers. As the procedure becomes more common in younger, active individuals, there is growing demand for durable, low-wear implant materials. Oxidized zirconium Zr2.5Nb alloy (Oxinium, Ox Zr) was introduced as a promising alternative, designed to combine the strength of metal with the low-friction properties of ceramic. Oxinium is created by thermal heat treatment of zirconium-niobium alloy, resulting in a 4–5 µm thick ceramic-like surface diffusion layer. Oxinium femoral heads were expected to reduce wear and extend implant longevity. However, clinical reports have revealed complications. Findings include wear deformation of the Oxinium head, polyethylene liner dislocation, and metallosis in surrounding tissue. These failures are frequently associated with dislocation or impingement between the metal acetabular cup and the femoral head. We report on the case of 64 years old male his primary THA was in 2009 and revision surgery in 2021 after severe metallosis. The surface and subsurface of Oxinium head was examined by surface analytical method XPS and micro-indentation hardness measurements. These observations challenge the initial claims regarding Oxinium’s durability and wear resistance. In certain patients, particularly those at risk of joint instability or dislocation, Oxinium components may lead to accelerated wear, severe metallosis, and reduced implant longevity. The interface between an Oxinium femoral head and a highly cross-linked polyethylene (HXLPE) liner is critical to the long-term success of total hip arthroplasty (THA), particularly in preventing dislocation and wear-related complications. The Oxinium–HXLPE interface shows promise, but more biomechanical and clinical data are needed to refine implant design and surgical protocols.