Who needs a knee replacement?
Osteoarthritis is the main reason for almost all knee replacements. As joint surface cartilage wears out, the bottom of the thigh bone starts rubbing on the top of the shin bone, causing pain and difficulty in walking. More women than men have knee replacements, and most are around retirement age. But the operation is increasingly being offered to younger people who want to carry on being active. Up to 95 per cent of knee replacements last ten years, and many will last more than 20 years, depending on what activities their owners do. Second or even third replacements are usually successful, but being overweight can make pain worse, and increase the risk of complications.