Hyaluronic acid injection procedures are also known by the term viscosupplementation.

Osteoarthritis is a joint disease that mostly affects the cartilage. Cartilage is the tissue that covers the ends of bones of a joint. When healthy, cartilage allows bones to glide over one another and provides a shock absorber function. The normal knee joint also contains a small amount of fluid called synovial fluid which is a thick gel-like substance that basically cushions the joint, and provides lubrication to reduce friction.

Hyaluronic acid injections are similar to substances that occur normally in your joint. They help joints to work properly by acting like lubricants or shock absorbers. The medication is injected into the knee by your doctor to relieve pain caused by osteoarthritis. Pharmaceutical companies in the United States have three hyaluronic acid-based products available. These are known by the brand names Hyalgan, Synvisc, and Supartz.