Comparison and appraisal of techniques for the determination of material loss from tapered orthopaedic surfaces

This review examines the challenges associated with quantifying material loss at modular junctions. Determination of material loss from retrieved orthopaedic surfaces is regarded as a prerequisite for the evaluation of long-term implant performance. Methods previously adopted to overcome the challenges associated with determining material loss from non-articular surfaces will be presented and discussed in this paper. Total Hip Replacement (THR) is regarded as one of the most successful and cost-effective surgical interventions for the treatment of advanced osteoarthritis. The use of modular components offers surgeons an array of possible implant combinations to intraoperatively optimise range of motion and soft tissue tension. However, the taper interface used to connect modular components has been suggested to contribute to premature implant failure through the release of metal debris and corrosion products. Geometrical and topographical measurement of explanted modular interfaces has been used to correlate multifarious variables with an absolute volumetric value for material loss. To improve modular implant performance, medical device manufacturers have adopted numerous design philosophies, each presenting a unique set of challenges for the measurement of material loss. This review summarises the approaches used in previous studies to overcome these challenges and identifies future work required in this area. This field of research is currently the subject of discussion within standards bodies to create recommended best practices for centres to follow.