Glucosamine, with or without chondroitin, is a popular and high selling neutraceutical with claims to improve symptoms associated with painful osteoarthritis (OA). Clinical trials testing purported benefits have yielded mixed results, with manufacturer sponsored trials showing benefits while most unbiased studies have generally not shown benefit over placebo. Previously, in a large clinical trial of glucosamine hydrocholoride with or without chondroitin sulfate, neither agent demonstrated efficacy over placebo in treating pain in individuals with knee OA.
Large scale, independent studies of glucosamine and/or chondroitin have not shown a definitive benefit for the treatment of painful knee osteoarthritis (OA) and the effect of retarding knee OA progression remains controversial. Despite this, the use of glucosamine as a complementary/alternative medicine is widespread, amounting to a multi-million dollar industry. Many users take glucosamine for OA at sites other than the knee, sites which have received little to no study of efficacy.
Knee pain from osteoarthritis (OA) tends to be poorly correlated to degree of cartilage loss. Other factors related to knee OA, including bone marrow edema and synovitis, may be more proximal determinants of pain in knee OA. Synovitis is usually quite limited in knee OA and difficult to quantify on physical exam. Magnetic resonance (MR) imaging is a more sensitive technique for assessing synovitis in knee OA.
Pain perception in osteoarthritis (OA) is complex, with the intensity of pain reported in affected individuals often with little correlation to structural damage. Few studies have explored the neural networks responsible for processing pain in OA.
Exercise may decrease the risk of developing knee osteoarthritis (OA) via trophic effects on cartilage and muscle strengthening. However, exercise may also predispose to knee OA via joint loading and the potential for traumatic injury. These predisposing factors may be more important in individuals who are overweight or obese.