Knee injections are not all the same. In this study my colleagues and I compared the efficacy of three different injections commonly administered into the knee joint.
Around the world steroids are the most commonly used of the two agents, and are given to relieve pain. If symptoms continue then the doctor may try hyaluronic acid or platelet-rich plasma (PRP), and their use is recently on the increasing.
What is triamcinolone?
Triamcinolone is one of many steroids that can be injected in the joint. Depomedrol is the second commonly used steroid.
What is hyaluronic acid?
Hyaluronic Acid (HA) is a very long chain of disaccharides (sugars) and these are present in all connective tissues. As we age, levels of hyaluronic acid fall - some say by as much as 50 percent. That is why supplementing with hyaluronic acid can help promote healthy joints. It is a major component of both cartilage and the synovial fluid that bathes these joints, binding to water to create a thick, gelatinous substance that lubricates and protects the cartilage.
What is platelet-rich plasma?
Platelet-rich plasma is a blood-derived product comprised of blood plasma enriched with platelets. PRP contains different growth products and chemicals called cytokines that facilitate cell growth and healing.
We undertook this study as part of a programme to test the efficacy of these three different commonly used injections, in terms of their ability to control pain and the sustainability of their effect.
We found all three of these injections to be effective in controlling knee pain, but the effect of steroids wanes earliest and that of PRP lasts longer, with HA in between.
The injections can be repeated after every few months. But repeated use of steroids is not advisable.
Intra-articular hyaluronic acid is superior to steroids in knee osteoarthritis: A comparative, randomized study. Vaishya R, Pandit R, Agarwal AK, Vijay V. Journal of Clinical Orthpaedics and Trauma. Available online 30 September 2016