Table 1. Summary of the study characteristics and findings.
VAS: Visual Analog Score, HHS: Harris Hip Score, WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index
| Author | Year | Sample Size | Intervention | Control | Follow-up duration | Main outcomes | Safety findings | Quality assessment | |
| Pain (VAS) | Function | ||||||||
| Villanova-López et al. [11] | 2020 | 74 | PRP injections | Hyaluronic Acid (HA) | 12 months | Significant pain reduction in the both groups. P-value < 0.01 at 12-month follow-up. | Significant improved function (HHS and WOMAC]. P-value < 0.01 at 12 months | No adverse effects were recorded (0 patients) | Low risk of bias |
| Di Sante et al. [12] | 2016 | 43 | PRP injections | Hyaluronic Acid | 16 weeks | Significant pain reduction (VAS) at 4 weeks (p-value <0.01) but not at 16 weeks for PRP group (p-value > 0.05) | No significant improvement in function (WOMAC) at 4 or 16 weeks for PRP group (p-value > 0.05) | No complications (0 patients) | Some concerns |
| Dallari et al. [13] | 2016 | 111 | PRP injections | HA and combination therapy | 12 months | Significant pain reduction (VAS) at all follow-up visits. PRP group had lowest VAS, especially at six months (p-value <0.0005 (PRP vs, HA) and p-value .007 (PRP vs. PRP-HA). | Significantly improved function (WOMAC), especially at 2 months (mean 73; 95% CI, 68-68) and 6 months (mean 72; 95% CI, 67-76) but not at 12 months (p-value > 0.05). | No serious adverse events | Low risk of bias |
| Nouri et al. [14] | 2022 | 105 | PRP injections | HA and combination therapy | 6 months | Significant pain reduction (VAS) at all follow-up visits. p-value <01 all groups compared to the baseline. | Significantly improved function (WOMAC and Lequesne) at all follow-up visits. p-value <01 all groups compared to baseline. More significant functional improvement in PRP and PRP-HA groups compared to the HA group. P-value 0.041, 0.002, respectively) | Low rates of minor side effects (pain, warmth, stiffness) in 17 patients. PRP and PRP-HA groups had more pain compared to the HA group. P-value 0.001 | Some concerns |
| Doria et al. [15] | 2017 | 80 | PRP injections | HA | 12 months | Significant pain reduction in the both groups. P-value < 0.01 at six-month and 12-month follow-up. | Significant improved function (HHS and WOMAC). P-value < 0.01 at six months and 12 months | No major adverse events reported but significantly higher post-injection pain reaction in PRP group. P-value 0.043 | Some concerns |