UKR—time for caution?

Shortly before taking over as editor of The Knee in 2000, I wrote a review article on unicompartmental knee replacement. I make no apology for doing so again just before relinquishing the Editor’s position, because so much has changed in the last 5 years. The initial review was largely concerned with whether unicompartmental replacement was a reasonable procedure to undertake. In the USA, UK and Australia, there has been a major increase in the prevalence of this procedure, which had always been more popular in mainland Europe. Large numbers of UKRs are now being inserted by surgeons of varying experience, which inevitably means more failures are occurring. Debate now centres not on whether UKR should be performed but on the specific indications, which type, by whom and with what expectation; particularly in relation to rapidity of rehabilitation, function and long-term survivorship.