Studies Suggest Knee Osteoarthritis Responds to Glucosamine, Chondroitin
By R. Scott Oliver, MD

For the aging athlete, arthritis is a tough problem. Arthritis remains second only to heart disease as the cause of disability in our population in the United States. As the Baby Boomers are becoming older, more attention is being paid to conservative treatment of arthritis.

New on the horizon are trials of supplements that appear promising in the treatment of knee osteoarthritis. These over-the-counter supplements have been helpful in decreasing inflammation of arthritis in the knee; more importantly, they have no apparent side effects. Osteoarthritis occurs when there is significant wearing of the articular cartilage of the joint.

Articular cartilage in the cushioning substance on the ends of bones, and it acts as a "tire tread" for the joint. As the articular cartilage is worn down, swelling and pain occur because of the accompanying inflammation. Articular cartilage consists of glycosaminoglycans. This substance is very viscoelastic and works well as a cushion. It is an excellent molecule for weight bearing. The most common glycosaminoglycan is chondroitin sulfate. It is presently available to us derived from cow trachea. Another component is an amino sugar, glucosamine. Glucosamine is available to us from chitin, found in the shells of crabs. The use of these supplements provides a mild anti-inflammatory effect of knee osteoarthritis and it has been suggested that they may help the growth of articular cartilage.

Orthopedic surgeons are just beginning to become aware of the potential benefits of these supplements. Currently, the recommended dose is Glucosamine 500 mgs, three times a day. Chondroitin sulfate can be added, and could be of further benefit as well in a combination. Glucosamine should be taken for a four to six-week period. The patient should re-evaluate symptoms at that time to assess whether or not benefit has been achieved. If so, glucosamine can be continued.

It is important to note that glucosamine and chondroitin sulfate provide symptomatic relief in 50 percent of patients who have mild to moderate osteoarthritis within the knee joint. It has not been shown to increase articular cartilage: there has been no change noted on x-rays. More medical studies will be required before conclusive recommendations will be provided to patients with knee osteoarthritis.