Liner dissociation leading to catastrophic failure of an Oxinium femoral head

Abstract

Oxinium is an alternative bearing surface designed to emulate the superior wear and scratch properties of ceramic femoral heads in total hip arthroplasty while minimizing the risk for brittle fracturing. However, recent studies have indicated that hip dislocation following total hip arthroplasty may be a risk factor for catastrophic failure of the femoral head. Here, we report on a novel case of a catastrophic Oxinium head and polyethylene liner failure in the absence of previous hip dislocation or trauma and review the probable failure mechanism. This report underscores the need to be vigilant about proper acetabular cup and liner seating, particularly in the setting of Oxinium femoral head use. In the event of Oxinium head failure, metallosis may compromise stabilizing soft tissues including the abductors. Dual-mobility articulation, which was successful in this case, is one option to consider when the risk for chronic redislocation is elevated. Keywords: Liner dissociation, Dual-mobility system, Oxinium, Oxidized zirconium, Total hip arthroplasty, Total hip replacement