This includes distinguishing between severe disease and common minor disability

The name “osteoarthritis” arose from observation of the striking overgrowth of marginal and subchondral bone by the pathologists and radiologists who classified the different forms of joint disease at the turn of the century.1 For many years it was regarded as a simple, age related, degenerative, “wear and tear” phenomenon, a view that led to negative approaches to both research and treatment. Over recent years this has changed: there is now plenty of interest in osteoarthritis, and the research effort has led to several new treatments, such as lubricating injections into joints2 and cartilage transplants.3 But this trend has inherent dangers. Not only do we not yet know whether these new treatments really help patients in the long term; the introduction of complex, expensive treatments for a disorder that may affect a quarter of the world's older people is unlikely to be of much use to most doctors or patients. We need to take stock and ask ourselves if current approaches are appropriate.

Osteoarthritis is obviously important: it is the main cause of joint replacement surgery and is so common that in the developed world it is set to become the fourth …