Platelet-rich plasma in the conservative treatment of painful tendinopathy: a systematic review and meta-analysis of controlled studies

Platelet-rich plasma (PRP) seeks to meet the multifaceted demand of degenerated tendons providing several molecules capable of boosting healing. PRP is used for managing tendinopathy, but its efficacy is controversial. Electronic databases were searched for clinical studies assessing PRP efficacy. Methodological quality was evaluated using the methods described in the Cochrane Handbook for systematic reviews. Thirteen prospective controlled studies, comprising 886 patients and diverse tendons were included; 53.8% of studies used identical PRP protocol. Sources of heterogeneity included different comparators, outcome scores, follow-up periods and diverse injection protocols, but not PRP formulation per se. Pooling pain outcomes over time and across different tendons showed that L-PRP injections ameliorated pain in the intermediate-long term compared with control interventions, weighted mean difference (95% CI): 3 months, -0.61 (-0.97, -0.25); 1 year, -1.56 (-2.27, -0.83). However, these findings cannot be applied to the management of individual patients given low power and precision. Further studies circumventing heterogeneity are needed to reach firm conclusions. Available evidence can help to overcome hurdles to future clinical research and bring forward PRP therapies.