Hyaluronic acid therapy.

A significant amount of evidence exists suggesting beneficial effects of intra-articular hyaluronate preparations in treating the symptoms of OA. The beneficial effects of these compounds tend to persist for several months after cessation of therapy, unlike anti-inflammatory drug effects. In addition, several clinical trials comparing these agents to anti-inflammatory medications indicate efficacy of symptom improvement equivalent to that of the anti-inflammatories. A few clinical studies have failed to demonstrate an effect, and clearly much work remains to be done in this area to fully determine rational treatment strategies with these agents. The symptom improvement is generally moderate, and additive effects of these agents with anti-inflammatories have not been demonstrated. Adverse local reactions have been reported in some clinical series of hyaluronate injections. Although the invasive nature of the procedure is a drawback, overall it appears to be well tolerated and is probably not harmful to articular cartilage, a major advantage over the widely practiced introduction of intra-articular steroids. Documentation of true chondroprotective effects or alteration of the natural history of cartilage degeneration by these agents is lacking in the clinical literature and awaits further study. Cost effectiveness of this therapy versus other treatments, including the costs of treatment of side effects, also requires further rigorous evaluation, and may influence acceptability of this form of treatment to various health care providers and organizations.