Multi- versus Single Injections of Platelet-Rich Plasma for Knee Osteoarthritis: Are the Benefits Worth the Risk ?

This systematic review and meta-analysis evaluated whether multiple intra-articular (IA) platelet-rich plasma (PRP) injections are more effective and/or safer than a single PRP injection in knee osteoarthritis (OA). Across 8 RCTs, multiple PRP injections provided significantly greater pain relief at 3, 6, and 12 months, though differences in functional outcomes (WOMAC, IKDC) were not statistically significant and supported by very low-quality evidence. Single injections were associated with fewer adverse events. Despite the heterogeneity in injection protocols and PRP formulations, the findings suggest that multiple PRP injections may offer enhanced pain reduction with minor added risks—though higher-quality trials are needed to confirm these results.