Update on viscosupplementation in the treatment of osteoarthritis of the foot and ankle.

In the recent past, nonsurgical treatment of osteoarthritis was limited to rest, immobilization, physical therapy, activity modifications, nonsteroidal anti-inflammatory drugs, analgesics, weight loss, assistive devices for walking, and corticosteroid injections. Viscosupplementation is a welcome addition to the nonsurgical armamentarium available to physicians. It is used to introduce hyaluronic acid into the joint to provide initial lubrication and shock absorption, and to change the long-term disease process. This article discusses the pathology of osteoarthritis; the characteristics, physiology, and administration of commercial viscosupplements; and reviews the research on hyaluronic acid use in the foot and ankle. It concludes that additional studies are required to test the safety and efficacy of this treatment in other parts of the foot.