What is Viscosupplementation?
Inside a healthy joint, there is a small amount of lubricating fluid, called synovial fluid. The primary composition of synovial fluid is hyaluronic acid. Hyaluronic acid provides lubrication in the joint movements. It also absorbs shock which goes through the joint, e.g. when the person hops or jumps.
In osteoarthritis, the cartilage in the joint wears out and the synovial fluid also becomes diseased and lose its lubricating and shock-absorbing abilities. The joint loses the protective mechanism and pain, stiffness and loss of function occur in the joint.
Hyaluronans are substances similar to hyaluronic acid in synovial fluid, in terms of lubricating and shock-absorbing abilities. Hyaluronans are injected into the joint affected by osteoarthritis, and they replace the diseased synovial fluid, protecting the already damaged cartilage lining from further damage caused by friction.
When is Viscosupplementation considered for treatment?
Viscosupplementation is not regarded as a first line treatment for joint osteoarthritis. Therefore, it is usually considered when conventional and evidence-based treatments, such as exercise, weight loss, physical therapy have been tried and have not resulted in the desired outcomes. There is no guarantee that viscosupplementation will improve your symptoms.
How is it done?
The doctor will clean the joint with anti-septic solutions. He or she may inject a local anaesthetic to the joint, and withdraw some of the diseased synovial fluid from the joint before injecting the hyaluronan preparation into the joint.
What should I do after viscosupplemention?
1) Rest the affected joint for the first 24-48 hours from moderate to vigorous exercise. Daily activities are ok. Ideally, you should avoid intensive activities, e.g. running, for the first 2 weeks to prevent joint fluid build-up.
2) If there is pain during this period, ice the area and/or take pain medications.
3) Any bandage placed over the injected site can be removed after 1-2 hours, if there is no bleeding.
How long does the pain relief last?
The onset of pain relief varies between individuals. Most patients experienced full pain relief 6 weeks post-injection, but there are patients who experienced pain relief as soon as 1 week post-injection.
Viscosupplementation is not a cure for osteoarthritis, and hence there may not be permanent symptom relief. Although a single viscosupplementation can provide up to 6 months of pain relief. Hence there might be a need for a repeat injection
Possible Risks or Side Effects
Viscosupplementation is a safe procedure. There may be pain, or bleeding to the injection site. Some patients might also develop a rash. These are usually mild and do not last more than 3 – 5 days.
There is also a small risk of joint fluid build-up, infection, or acute swelling (flare reaction). If you have symptoms such as a fever, find that movement is painful, or the joint feels warm, see your family doctor immediately, or go to our Accident and Emergency Department, if you suspect that you have developed a joint infection or flare reaction.