The Efficacy of Platelet-Rich Plasma on Tendon and Ligament Healing: A Systematic Review and Meta-analysis With Bias Assessment

Abstract

<div class="section"> <a class="named-anchor" id="S1"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e126">Background:</h5> <p id="P1">There has been a surge in high level studies investigating platelet rich plasma (PRP) for tendon and ligament injuries. A number of meta-analysis have been published, but few studies have focused exclusively on tendon and ligament pathology. </p> </div><div class="section"> <a class="named-anchor" id="S2"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e131">Purpose:</h5> <p id="P2">To perform a meta-analysis assessing the ability of PRP to reduce pain in patients with tendon and ligament injuries. </p> </div><div class="section"> <a class="named-anchor" id="S3"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e136">Study Design:</h5> <p id="P3">Systematic review and meta-analysis</p> </div><div class="section"> <a class="named-anchor" id="S4"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e141">Methods:</h5> <p id="P4">This study followed the PRISMA (Preferred Reporting Items and Systematic Reviews and Meta-Analyses) guidelines. A comprehensive search of the literature was carried out in April 2017 using electronic databases PubMed, MEDLINE, and the Cochrane Library. Only Level I studies were included. Platelet and leukocyte count, injection volume, kit used, participant age/gender, comparator, and activating agent used were recorded. The short-term and long-term efficacy of PRP was assessed using the visual analog scale (VAS), which measures pain intensity. Pathology subgroups (rotator cuff, tendinopathy, ACL, and lateral epicondylitis) were evaluated. Funnel plots and Egger’s test were used to screen for publication bias and sensitivity analysis was performed to evaluate the impact of potential outliers by removing studies one at a time. </p> </div><div class="section"> <a class="named-anchor" id="S5"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e146">Results:</h5> <p id="P5">Thirty-seven articles were included in this review, 21 (1031 participants) of which could be included in the quantitative analysis. The majority of studies published investigated rotator cuff (38.1%) or lateral epicondylitis (38.1%). 17 studies (844 participants) reported short-term VAS data and 14 studies (771 participants) reported long-term VAS data. Overall, long-term follow-up results showed significantly less pain in the PRP group compared to control (WMD: −0.84; 95% CI: −1.23, −0.44; p&lt;0.01). Patients treated for rotator cuff injury (WMD: −0.53; 95% CI: −0.98, −0.09; p=0.02) and lateral epicondylitis (WMD: −1.39; 95% CI: −2.49, −0.29; p=0.01) both reported significantly less pain in the long-term. Substantial heterogeneity was reported at baseline (I ²: 72.0%, p&lt;0.01), short term follow-up (I ²: 72.5%, p&lt;0.01), long term follow-up (I ²: 76.1%, p&lt;0.01), and overall (I ²: 75.8%, p&lt;0.01). The funnel plot appeared to be asymmetric, with some missingness at the lower right portion of the plot suggesting possible publication bias. </p> </div><div class="section"> <a class="named-anchor" id="S6"> <!-- named anchor --> </a> <h5 class="section-title" id="d9213234e163">Conclusion:</h5> <p id="P6">This review shows that PRP may reduce the pain associated with lateral epicondylitis and rotator cuff pathology. </p> </div>