Expert Q&A: Viscosupplements

Dr. Tim Bhattacharyya is the head of Clinical and Investigative Orthopedics at the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). NIAMS is a division of the National Institutes of Health.

What is viscosupplementation?

Viscosupplementation is a procedure for patients with osteoarthritis (OA) of the knee. A natural lubrication fluid called synovial fluid resides in each joint, including the knee. Hyaluronic acid, which functions to lubricate, or grease, your joints during movement, exists naturally in the synovial fluid. As you get older, the chemicals in hyaluronic acid begin breaking down, and your levels of hyaluronic acid decrease. Lower levels of the natural lubricant may limit joint motion and eventually cause pain and stiffness in the joint. A viscosupplement injection replaces the missing hyaluronic acid in your synovial fluid. This temporarily increases the knee’s ability to move without causing you pain or discomfort.

At what point in treatment would a person begin using viscosupplements?

Viscosupplements would be appropriate as a second- or third-line treatment plan for people with OA of the knee. If anti-inflammatory drugs are not working and other more conservative treatment plans have not relieved the pain and stiffness caused by OA of the knee, viscosupplements may be a useful treatment option.

Who is a good candidate for viscosupplement injections? Who is not?

It’s important to acknowledge that viscosupplements have a bit of controversy associated with them. Several analyses of multiple clinical trials have found that viscosupplements are not super effective at reducing the symptoms of OA of the knee. The research says that if viscosupplements are effective for a patient, the relief is typically very mild. While viscosupplements have their passionate believers, research suggests they aren’t very effective.

With that in mind, not everyone with OA of the knee should be considered as a candidate for viscosupplementation. In my opinion, viscosupplements are ideal for a patient who has moderate OA—their condition is not quite bone-on-bone contact. It is also ideal for people who have flare-ups or their knee begins bothering them as a result of a specific event, such as a fall or accident. These types of patients are the best candidates for viscosupplementation, not a patient who has suffered OA for years. 

Can viscosupplements be an alternative treatment for people looking to avoid surgery?

No, for people with severe OA, viscosupplements are not a substitute for total knee replacement. It’s important to not discard surgery as a treatment option for severe OA of the knee when other treatment options have not proven successful. A knee replacement operation is extremely effective if and when OA of the knee becomes that advanced. 

How do the different kinds of viscosupplements differ?

There are several brands of viscosupplements, but essentially, they are all very similar. Their differences are mainly in the number of injections and how long the effects last.

What are the risks of treating OA with viscosupplementation?

The risks are very minimal. Some patients will experience an inflammatory response or reaction at the point of injection. They may also experience pain and discomfort during the injection. Of course, there is always the risk of infection, but research demonstrates an infection occurs in less than one in 1,000 patients using viscosupplements.

How long do viscosupplementation injections last? How frequently do you need these injections?

Each type of viscosupplement has different protocols for how many injections you need and how long the results will last. Typically, a patient will need three injections over three weeks, one injection per week. The average treatment lasts around three months.

What medical professional should be performing these injections?

A rheumatologist or an orthopedic surgeon should be administering viscosupplement injections. I’ve seen cases of individuals receiving these injections at med spas, but a trained doctor is the only one who should be performing this procedure.