1000 Section - Comparative Efficacy of Ultrasound-guided intra-articular injection of Platelet-Rich Plasma (PRP), Hydrolyzed Type I Collagen, and Hyaluronic Acid in Knee Osteoarthritis: A Randomized Controlled Trial

To compare the effects of intra-articular PRP, hydrolyzed collagen, and HA on pain, stiffness, and functional outcomes in patients with symptomatic KOA.

Design:

In this randomized, double-blind clinical trial, 135 participants with Kellgren–Lawrence grade 2–3 KOA were allocated to three treatment groups, and 126 completed follow-ups and were included in final analysis. All patients received three ultrasound-guided intra-articular injections of PRP, hydrolyzed collagen, or HA  at two-week intervals. Outcomes were assessed at baseline, 1 month, and 6 months.

Results: All three treatments demonstrated significant improvements in pain and function at 1 and 6 months. At 1 month, HA showed numerically greater improvements but between-group differences were not statistically significant. At 6 months, PRP and collagen achieved significantly greater improvements than HA only in Lequesne pain, activities of daily living and total scores, while no significant differences were observed between PRP and collagen. Differences in WOMAC function and VAS pain were present but not statistically significant. No serious adverse events occurred, and all treatments were well tolerated. The absence of adverse events is consistent with the established safety profile of IA PRP and collagen formulations.

Conclusion:

Intra-articular PRP, hydrolyzed collagen, and HA all improved pain and function in KOA, but PRP and collagen produced slightly more durable benefits at 6 months. All agents appear safe and effective. This study strengthen the growing comparative evidence supporting short and mid-term effects of biological, viscosupplements and biomaterial IA therapies in mild to moderate KOA and highlights the need for longer-term and future rigorously designed comparative trials.