What is Viscosupplementation?
Joint pain of osteoarthritis is commonly treated with hyaluronic acid replacement therapy. Hyaluronate is a natural substance normally secreted by the lining of joints called synovium. This lubricates and cushions the joints. In a healthy joint, synovial fluid contains the body’s own hyaluronate. Osteoarthritis reduces the synovial fluid’s ability to lubricate and protect the joints, thus causing pain. By adding laboratory-produced hyaluronic acid, we restore the synovial fluid’s ability to relieve joint friction, rebuild cartilage cushioning, and reduce wear and tear. We thereby renew joint fluid viscosity or gooeyness, hence the term, viscosupplementation.
Hyaluronic acid is a naturally occurring substance produced by all of our synovial joints. We can also produce an exact replica in the laboratory. Initially we found this substance in the combs of roosters, but lab reproduction is much more efficient. Osteoarthritis affected joints have lower than normal levels of this fluid causing difficulty in movement, friction and grinding. Because osteoarthritis is progressive and has no cure, over time the pain and stiffness worsen. Viscosupplementation is most commonly used as a treatment for this pain and stiffness, and as alternative to surgery. It is currently FDA approved for the knee, but can be used off-label for the hip, shoulder and ankle.
Effects of Hyaluronic Acid
The major benefit of HA therapy is relief of pain and improvement of mobility. It can facilitate a return to exercise which improves cardiovascular health along with muscle tone and weight management
In clinical trials, there were no reported drug interactions with HA. The most common adverse events were injection-site tenderness, joint swelling and irritation.
Initially, after sterilizing the injection site, any excess joint fluid is removed. This is especially necessary in the knee. Then, premeasured amounts of commercially available hyaluronic acid are injected into the joint under image guidance. As the name suggests, viscosupplementation artificially supplements the amount of natural HA and improves joint fluid viscosity. This treatment is designed to lubricate and cushion the joint. Typically, three injections, spaced a week apart, are required for a full series. If the procedure proves to be effective, the injection series can be repeated at periodic intervals.
- The procedure facilitates better joint movement.
- The treatment reduces pain due to osteoarthritis.
- It helps in slowing osteoarthritis progression.
- It aids in restoring muscle strength and tone.
HA has been proven to provide long-lasting relief of osteoarthritis knee pain. In a published clinical trial, 3 injections of HA given once a week over 3 weeks reduced knee pain for an average of 9 months. Some patients have experienced pain relief after only one injection. Treatment with HA gave patients a 66% better reduction in pain with the first cycle of 3 injections compared against a placebo.