Knee osteoarthritis (OA) is a chronic, painful disease associated with considerable morbidity, costs and disability. It is estimated that over a third of people aged over 60 have radiographic knee OA2 and over 50% of these with knee OA will go on to have a total knee replacement in their lifetime. At present there are no licensed treatments that alter disease progress and management is primarily concerned with symptom control to retain or improve joint function, although a trial of strontium ranelate showed promising results.