Knee osteoarthritis (KOA), Platelet-rich plasma (PRP), Hyaluronic acid (HA), Western ontario and McMaster universities arthritis index (WOMAC) total scores, Visual analogue scale (VAS)scores, International knee documentation committee (IKDC) scores, Orthopedic surgery, RD701-811, Diseases of the musculoskeletal system, RC925-935

Abstract Introduction KOA, a chronic degenerative joint disease, is commonly treated with intra-articular HA and PRP, used alone or in combination. However, the efficacy and safety of combination therapy (PRP + HA) remain unclear. Aim The aim of this systematic review and meta-analysis is to assess the clinical effectiveness and safety profile of PRP + HA versus PRP monotherapy for KOA. Material and methods A systematic search was conducted using four electronic databases (PubMed, EMBASE, Scopus, and Cochrane Library) to select publications published in peer-reviewed journals. The mean difference (MD) and risk ratio (RR) was calculated, along with their 95% confidence intervals. We assessed heterogeneity using Cochrane Q and I2statistics and the appropriate p-value. The analysis used RevMan 5.4. GRADE system was used for evidence assessment for each outcome parameter. Results This meta-analysis of 11 RCTs (n = 1023 KOA patients) revealed that PRP + HA has substantial effectiveness than PRP alone in reducing OMAC total scores [MD -1.77 (95% CI -2.20 to − 1.34); I2 = 10%, and p