A new study published in the American Journal of Sports Medicine looked at the use of Platelet Rich Plasma (PRP) injections for osteoarthritis of the knee both from a safety and efficacy standpoint.
This was a small study consisting of 30 patients who received an intra-articular PRP injection in the knee consecutively for 3 weeks. Specifically, 3 to 8 mL of PRP was injected. Patients in the control group received 3 intra-articular injections of saline. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score was used to assess outcome.
The results showed that those who received the PRP injections had a 78% improvement from baseline whereas the controls only had a 7% improvement at 12 months. WOMAC scores improved to a greater degree in the PRP group than controls starting at 2 weeks. This effect lasted throughout the duration of the study.
Overall there were no adverse events associated with the PRP injections. As this study was sanctioned by the Food and Drug Administration (FDA), the small study size was mandated to evaluate for safety. The results of this study support prior observations by Duymus et al (Knee Surgery Sports Traumatology Arthroscopy 2016) and Kavadar et al (Journal of Physical Therapy Science 2015). A recent systematic review by Meheux et al (Arthroscopy 2016) which included 6 published studies with a minimum of 6 months of follow-up also reported significant clinical efficacy for PRP injections in the treatment of knee osteoarthritis up to 12 months.
Smith P. Intra-articular autologous conditioned plasma injections provide safe and efficacious treatment for knee osteoarthritis: an FDA-sanctioned, randomized, double-blind, placebo-controlled trial. American Journal of Sports Medicine. 2016. Apr 44(4): 884-891.
Duymus TM et al. Choice of intra-articular injection in treatment of knee osteoarthritis: platelet-rich plasma, hyaluronic acid or ozone options. Knee Surgery, Sports Traumatology, Arthroscopy. 2016. Apr 7.
Kavadar G. et al. Effectieness of platelet-rich plasma in the treatment of moderate knee osteoarthritis: a randomized prospective study. Journal of Physical Therapy Science. 2015: Dec 27(12): 3863-3867.
Meheux CJ et al. Efficacy of Intra-articular Platelet-Rich Plasma Injections in Knee Osteoarthritis: A systematic review. Arthroscopy. 2016. Mar 32(3): 495-505.