Osteoarthritis (OA) is a chronic disease causing deterioration of the joint cartilage and the formation of bone spurs at the margins of the joints. Knee OA causes substantial pain, suffering, and disability, as well as enormous economic burden on the patient; unfortunately, treatment provides relief but not a cure. The majority of patients with symptomatic knee OA do not attain satisfactory long-term relief, even with recent advances in pain relievers. Analgesic treatment may relieve the pain but does not improve biomechanics and may even aggravate OA.