Osteoarthritis Clinic · Injection guide
Viscosupplementation is a gel-like hyaluronic-acid injection meant to lubricate and cushion an osteoarthritic joint, most often the knee. Patients often call these gel injections. Our rheumatologist-led clinic in downtown Toronto uses Durolane, a single-injection product. The evidence is genuinely mixed and there is a fee, so it is worth understanding the benefits, the risks with numbers, the cost, and the aftercare before you decide.
Hyaluronic acid is a substance your joints make naturally. It helps the joint glide and absorb load. In osteoarthritis, this fluid thins out. Viscosupplementation adds hyaluronic acid back into the joint. We use Durolane, a single 3 mL injection containing 60 mg of purified sodium hyaluronate made by fermentation (non-animal stabilized hyaluronic acid, or NASHA). It is designed to stay in the joint for around a month while the effect builds over the following weeks.
Durolane is not covered by OHIP, so there is an out-of-pocket cost. The clinic will confirm the current fee with you before you book. The cost and coverage guide explains OHIP, extended health plans, and how to check yours.
Studies disagree. Some people get useful relief that can last up to about six months from a single injection, and it may work as well as a course of several older hyaluronic-acid injections. Across high-quality reviews, though, the average benefit over a placebo injection is small and not always meaningful. It tends to help more in mild-to-moderate arthritis and less in advanced, bone-on-bone joints. Expert groups differ: some, such as OARSI, suggest it for selected people who are not ready for surgery, while others, such as the American Academy of Orthopaedic Surgeons, do not recommend it. We will talk through whether it is reasonable for your joint and goals.
Durolane is generally well tolerated, and being non-animal it carries a low risk of allergy. The main issues are local. Based on the product information and published literature:
| Risk | How often, and what it means |
|---|---|
| Local reaction or flare | The most common effect. Temporary pain, swelling, or warmth at the joint, usually settling within a few days. Injection-site reactions are reported in about 2 to 3 in 100, and a temporary increase in joint pain in up to about 9 in 100. |
| Joint swelling | Mild to moderate swelling in roughly 1 to 2 in 100. |
| Pseudoseptic reaction | Very rare. A sudden, painful, swollen joint within a day or two that can look like an infection but is not. It still needs urgent assessment to rule out true infection. |
| Infection (septic arthritis) | Rare, in the same low range as any joint injection. |
| Allergic reaction | Rare. Signs would include hives, swelling of the face or throat, or trouble breathing, which need emergency care. |
The injection aftercare guide has the full version of this advice. For gentle exercises to do at home as the joint settles, see the knee home exercise programme.
No. The Durolane product is not covered by OHIP, so there is an out-of-pocket cost. Many extended health plans cover viscosupplementation in part or in full. The cost and coverage guide explains how to check your plan.
Some people get useful relief that can last up to about six months from a single injection. Across high-quality reviews, though, the average benefit over a placebo injection is small and not always meaningful.
Relief builds over the following weeks rather than straight away, so give it time.
No. A corticosteroid injection is meant to settle inflammation and often starts to help within a few days, for a shorter time. Durolane works more slowly and is meant to lubricate and cushion the joint.
The knee is the most common joint treated. Whether an injection suits your joint, and which one, is decided at your assessment.