Purpose: Platelet-rich plasma (PRP) and hyaluronic acid (HA) have been increasingly used in recent years to treat knee osteoarthritis (OA). However, whether PRP is superior to HA is controversial.
Methods: We conducted an electronic search of PubMed, Embase, ScienceDirect, and Cochrane library. The pooled data were analyzed using RevMan 5.1.
Results: Three prospective and ten randomized trials were identified. PRP injections reduced pain more effectively than HA injections in OA of the knee at 6 months (mean difference [MD]=-14.18; 95% confidence interval [CI]: -26.12 to -2.23; P =0.02; I ²=95%) and 12 months (MD=-15.25; 95% CI: -22.17 to -8.32; P <0.01; I ²=81%) of follow-up evaluated by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score, while the VAS showed no significant difference at 3 months (MD=-0.98; 95% CI: -2.55 to 0.59; P =0.22; I ²=90%) and 6 months (MD=-0.82; 95% CI: -1.80 to 0.16; P =0.1; I ²=83%). Additionally, similar results were observed for the function recovery according to the WOMAC function score and EuroQol-visual analog scales.
Conclusion: The intra-articular injection of PRP was not obviously superior to HA in knee OA. Due to the limited quality and data of the evidence currently available, more high-quality randomized controlled trials are required.
Keywords: knee, osteoarthritis, hyaluronic acid, platelet-rich plasma