Injections for knee osteoarthritis: how long are they effective?
Knee osteoarthritis (OA) is a degenerative condition where the cartilage that provides cushioning to the joint starts to wear.
Read more about the basics of knee OA here!
A common way to treat symptoms of knee OA is by direct injection of supplements into the joint.
The most common supplements used are:
- Corticosteroids (CS) – steroids used to reduce inflammation
- Hyaluronic Acid (HA) – a sugar molecule found naturally in cartilage used to lubricate the joint
- Platelet Rich Plasma (PRP) – platelets taking from your own blood to accelerate healing
Platelets are small fragments present in our blood that form clots to stop/prevent bleeding. They promote healing by recruiting growth factors to the area that stimulate the natural healing process in the body
The authors of a recent research study wanted to know how long the effects of these three common injections lasted.
To do this, the authors conducted a comprehensive review of all the relevant research studies in this area – called a “systematic review”.
They found 79 research studies that included 8,761 patients that fit their criteria.
What did they learn?
- All three types of injections were effective at reducing symptoms of pain and improving function
- CS and HA injections offered the best results at 4 – 6 weeks after treatment
- PRP injections offered the best long-term results, with patients reporting reduced pain and improved function even after 1 year
Read more about these types of injections for knee OA here
Edward S. Mojica, Danielle H. Markus, Anna M. Blaeser, Eoghan T. Hurley, Laith M. Jazrawi, Kirk A. Campbell, Eric J. Strauss. Estimated Time to Maximum Medical Improvement of Intra-articular Injections in the Treatment of Knee Osteoarthritis – A Systematic Review, Arthroscopy: The Journal of Arthroscopic & Related Surgery, 2021, ISSN 0749-8063, https://doi.org/10.1016/j.arthro.2021.08.026.