Introduction

Ultra high-molecular weight polyethylene (UHMWPE) particle-induced osteolysis is one of the major causes of arthroplasty revisions. The lack of particle clearance from the joint inevitably leads to the upregulation of the inflammatory cascade, resulting in bone resorption and implant loosening. Recent in vitro findings (Bladed CL et al. ORS 2011 and J Biomed Mater Res B Appl Biomater, 2012) have suggested that UHMWPE wear particles containing vitamin-E (VE) may have reduced functional biologic activity and decreased potential to cause osteolysis. This is of significant importance since VE-stabilised cross-linked UHMWPEs were recently introduced for clinical use, and there is no in vivo data determining the effects of wear debris from this new generation of implants. In this study we hypothesised that particles from VE-stabilised, radiation cross-linked UHMWPE (VE-UHMWPE) would cause reduced levels of osteolysis in a murine calvarial bone model when compared to virgin gamma irradiated cross-linked UHMWPE.