EFFECTIVENESS OF PLATELET-RICH PLASMA IN TREATMENT OF LATERAL EPICONDYLITIS – A SYSTEMATIC REVIEW AND META-ANALYSIS
Mikhail Saltychev PhD, MD 1, Katri Laimi, PhD, MD 1, Petri Virolainen, PhD, MD2, Michael Fredericson, MD3
1 Department of Physical and Rehabilitation Medicine, Turku University Hospital and University of Turku, Turku, Finland
2 Department of Orthopedics and Traumatology, Turku University Hospital and University of Turku, Turku, Finland
3 PM&R Sports Medicine Service, Department of Orthopaedic Surgery, Stanford University School of Medicine, CA, USA

Introduction
Regardless of extensive research, evidence on the effectiveness of platelet-rich plasma in lateral epicondylitis remains unclear.
Purpose
To investigate the evidence on effectiveness of PRP in lateral epicondylitis.
Method
Cochrane Controlled Trials Register (CENTRAL), Medline, Embase, Cinahl, Web of Science and Scopus databases. Random effects meta-analysis.
Results
Of the 1,154 records identified via database search, 18 were considered relevant for the qualitative analysis and 12 records for the quantitative analysis. Of the 18 studies, four were considered to have a high risk of systematic bias. PRP versus anesthetic or saline injection: when combining all the outcomes and all the time points, the pooled effect size of five samples was -0.6 (95% CI -1.1 to -0.2) with heterogeneity of 78% and NNT of 6.2 (95% CI 3.2 to 22.6). Respective figure for <3 months effect was -0.6 (95% -0.8 to -0.3) and the effect sizes for follow-ups over 3 months were insignificant. PRP versus cortisone injection: the pooled effect size of six samples was -1.1 (95% CI -1.4 to -0.7) with heterogeneity of 87% and moderate NNT of 3.2 (95% CI 2.2 to 5.4). PRP versus autologous whole blood: All the pooled effect sizes for all periods of follow-up were insignificant with heterogeneity 96%. PRP versus arthroscopy: when combining all the outcomes and all the time points, the pooled effect size of a single sample was -0.6 (95% CI -0.8 to -0.4) with high NNT of 6.4 (95% CI 4.6 to 10.0).
Conclusions
No strong evidence was found on the effectiveness of PRP in treatment of lateral epicondylitis when PRP was compared with local anesthetic or saline, corticosteroid injections, arthroscopic tendon release, or other treatment. Even though some effects of PRP were statistically significant, high NNT figures do not support the use of PRP over other treatments of lateral epicondylitis.