Osteoarthritis (OA) of the knee is a common condition that can result in pain and decreased functional capacity. Among new treatments for OA are biologic treatments including platelet rich plasma (PRP). This study evaluated the benefit of PRP as compared to that of hyaluronic acid (HA) for the treatment of OA.

This randomized, double-blind trial included adult patients less than 80 years of age with unilateral, symptomatic OA of the knee, and with imaging findings of cartilage degeneration. The subjects were randomly divided into two treatment groups, receiving three weekly intra-articular injections of PRP or high molecular weight HA. The participants were evaluated at baseline and then at two, six and 12 months, using the International Knee Documentation Committee's (IKDC) subjective measures, Knee Injury and OA Outcome Scores (KOOS), the EuroQol visual analogue scale Tegner scores, range of motion and transpatellar circumference.

Significant improvements were noted on all scales, except range of motion, for both treatment groups, including improvements in pain and function. No significant difference in any outcome was noted for between groups. There were two episodes of transient pain and swelling in the PRP group, with no severe events in either group.

This study of patients with osteoarthritis of the knee found that platelet rich plasma provides similar improvement in function and symptom reduction to those of hyaluronic acid.