Viscosupplementation is a procedure whereby a gel-like fluid called hyaluronan (also known as hyaluronic acid) is injected into the joint. Hyaluronan is a natural occurring substance found in the synovial (joint) fluid. It acts as a lubricant to enable the cartilage covered articulating surfaces of the joint to move smoothly over each other, and also aids as a shock absorber for joint loads.
Patients with osteoarthritis have a lower-than-normal concentration of hyaluronic acid in their joints. The theory is that adding hyaluronic acid to the arthritic joint will facilitate movement and reduce pain.
Viscosupplementation is usually only indicated or offered in the early stages of osteoarthritis (knee) that has failed to respond to other non-surgical treatment options such as simple analgesia, anti-inflammatory medication, physical therapy, weight reduction, and perhaps a corticosteroid injection into the joint.
Procedure
During the procedure, if there is any swelling in your knee, A/Prof Woodgate will remove (aspirate) the excess fluids before injecting the hyaluronic acid. Usually, the aspiration and the injection are done using only one needle inserted into the joint. A single dose or a total of three separate doses, over several weeks, may be required for optimum benefit. For the first 48 hours after the injection, you should avoid excessive weight bearing on the leg, such as standing for long periods, jogging or heavy lifting.
Side Effects
You may notice a local reaction, such as pain, warmth, and slight swelling immediately after the injection. These symptoms generally do not last long than 48 hours. Headache and joint stiffness have also been reported in some cases. Use of an ice pack or simple analgesics settles most injection related symptoms.
Complications
Rarely, patients may develop a local allergy-like reaction in the knee. In these cases, the knee may become full of fluid, red, warm, and painful. If this occurs, contact A/Prof Woodgate immediately. Infection and bleeding are also very rare complications of this procedure.
Outcomes
Some patients will not be helped by viscosupplementation. For those who report pain relief with the procedure, it may take several weeks to notice an improvement. How long the effects last varies from patient to patient. Some patients report pain-relieving effects for several months following the injections. If the injections are effective they may be repeated after a period of time, usually 6 months.
Although some patients report relief of arthritis symptoms with viscosupplementation, the procedure has never been shown to reverse the arthritic process or re-grow cartilage.
If fever develops or the pain and swelling fail to settle after 48 hours post injection, it is imperative that you contact A/Prof Woodgate.