Total hip arthroplasty is one of the greatest success stories in modern medicine. Since its inception in the late 1960s, millions have benefited from its ability to relieve pain and improve function, and it is now so successful that it is being used to treat arthritis of the hip in younger patients. The two problems with arthroplasty have always been fixation and wear. In the 1980s, the problem of fixation of components to the skeleton was overcome with both cemented and uncemented component designs that were developed to give excellent and long lasting fixation. Modifications of bearing surfaces and implant design have been introduced in an attempt to improve function, wear resistance, and implant survival. The recently published systematic review by Sedrakyan and colleagues used data from clinical trials, observational studies, and arthroplasty registries to compare traditional metal on polyethylene bearings with newer ceramic on ceramic and metal on metal bearings.1 The last two “hard on hard” bearings were thought to be advances that would reduce wear and facilitate hip resurfacing and the use of larger diameter femoral head sizes, which confer increased stability in arthroplasty.2 3 The review shows that the perceived advantages are not being reflected in outcomes …