Osteoarthritis and Injections
Unfortunately, osteoarthritis is NOT able to be treated by arthroscopy. For example, many patients with knee arthritis will have had a MRI showing a meniscal tear – this is secondary to the inflammation caused by osteoarthritis. Multiple randomized controlled trials have proven that a knee arthroscopy and a meniscal trim will not improve a patient’s pain in the setting of osteoarthritis. Hip and shoulder arthroscopy also do not help in the setting of cartilage damage.
There are good options however to reduce pain and improve functions. Physiotherapy can help. Strengthening the leg muscles by riding an exercise / stationary bike three times a week for 30 minutes can help knee OA, as can working out in a gym.
Other options include injections such as cortisone, hyaluronic acid, and platelet-rich plasma (PRP).
Cortisone injections are very effective, but typically only work for 2 to 6 weeks. In the setting of the need for urgent relief, such as imminent sport event, holiday, or personal event, these can be useful.
Hyaluronic acid (HA) is an off the shelf injection has been shown to be superior to cortisone. Injections such as Durolane are covered by private health insurance, but typically last for 3 – 6 months. These can be repeated.
At this time, platelet-rich plasma or PRP is likely the gold standard treatment for osteoarthritis of the knee and hip. PRP is prepared by taking 15 mls of your own blood, and spinning it in a centrifuge, which separates the red and white blood cells (which can stimulate a pro-inflammatory reaction) from the platelets and plasma which can provide a potent ant-inflammatory reaction, reducing the pain of arthritis. Unfortunately, despite abundant evidence of its efficacy in reducing pain for for up to 12 months, PRP injections are not covered by either OHIP or private health funds.
Newer options are coming onto the market, such as N-Stride. This product, similar to PRP, is designed to have improved concentrations of Interleukin-1 Receptor Antagonist (IL1-Ra), by exposing blood products to acrylic beads. It is thought that this may further enhance the anti-inflammatory properties of PRP. At this time, while IL1-Ra products have been shown to be safe, their superiority to PRP is at this time unproven. For this reason, N-Stride should probably be reserved for those in whom PRP injections are ineffective, until further evidence is published.
Injections are very safe. There is a 1/1000 risk of deep infection. There is approximately a 20% chance that injections do not work. Patients will often feel pain and swelling in the joint (hip, knee or shoulder) for 1 – 2 days which then subsides. Patients should avoid physical activity until this subsides. There is some evidence that anti-inflammatory medications / NSAIDS (such as ibuprofen, voltaren, naprosen, celebrex) can interfere with the effect of PRP – it is best to avoid these for two weeks after an injection of PRP and use Tylenol for pain relief instead.
Ultimately patients who fail nonoperative treatment are candidates for joint replacement. However, joint replacement is a very large operation with significant risks, and we will do everything we can to avoid you having to undertake this option.
Link to evidence for injections for osteoarthritis: https://drtimdwyer.com/blog-2/
For a link to Dr Dwyer’s publications on PRP:
https://www.ncbi.nlm.nih.gov/pubmed/?term=dwyer+tim+prp
For a link to Dr Dwyer’s publications on IL1-Ra
Dr. Tim Dwyer 