A critical appraisal of the evidence regarding the choice of common bearing couples available for total hip arthroplasty

There are a variety of materials used in bearing components in total hip replacement (THR). Metal-on- polyethylene replacements, having undergone small technical refinements in design over the last 30-40 years, give, according to the Scandinavian hip register, very good 10-year outcomes. However, aseptic loosening, caused to a great extent by adverse biological local reactions, induced by wear products from the articular surfaces, remains a serious problem. Thus, the debate and challenge of finding the best bearing surfaces continues. Technical improvements have been advocated in recent times to improve the replacement bearing longevity. Other than discussing such improvement, the paper looks at the evidence surrounding materials that are commonly used in total hip arthroplasty. This has been done to empower surgeons to make more informed decisions when choosing the bearing surfaces for their patients.