Viscosupplementation may be a therapeutic option for individuals with osteoarthritis of the knee. Although there is no cure for osteoarthritis of the knee, there are many treatment options available. The primary goals of treatment are to relieve pain and restore function. In this procedure, a thick fluid called hyaluronic acid is injected into the knee joint. Hyaluronic acid is a naturally occurring substance found in the synovial (joint) fluid. It acts as a lubricant to enable bones to move smoothly over each other and as a shock absorber for joint loads.
People with osteoarthritis ("wear-and-tear" arthritis) have a lower-than-normal concentration of hyaluronic acid in their joints. Viscosupplements are gel-like substances, hyaluronates, that mimic the properties of naturally occurring joint fluid. Currently, there are five FDA approved hyaluronates which include: Hyalgan, Supartz, Synvisc, Euflexxa, and Orthovisc. These hyaluronates are injected into the joint. The number of injections performed varies with the type of viscosupplement used.