knee was fine; perhaps the problem was his hip? In 2005, with the groin pain getting worse, Atkins, who has private insurance, went to see a consultant, Andrew Cobb. Cobb, a distinguished orthopaedic surgeon doing a mix of private and NHS work, recommended a hip replacement of a new design called ASR, produced by the American company DePuy, a subsidiary of Johnson & Johnson. Apart from being more expensive, the ASR hip differed from the total hip replacement pioneered by John Charnley in two ways. Both surfaces, ball and cup, are made of cobalt-chromium -- a so-called 'metal on metal' hip. And instead of cutting off the top of the thigh bone and pushing a spar deep inside the bone to hold the ball of the joint in place, the ball is a hollow hemisphere with a short stalk, like a mushroom, designed to cover the ball at the top of the femur rather than completely replace it. Hence the claim that the hip is not being replaced, merely 'resurfaced'. Resurfacing means less bone is lost than in a full replacement. Even the most successful conventional hip replacements seldom last much beyond ten years, and it's easier and safer to put in a total hip replacement after a resurfacing than to put in one replacement after another. In other words, hip resurfacing is seen as ideal for the young and the active, people who are generally healthy and are likely to wear out at least one hip device. The DePuy