Effects of Platelet Rich Plasma in Rotator Cuff Tendinopathies and Partial Tears - A Systematic Review

Abstract

Background: Shoulder pain and dysfunction are frequently caused by rotator cuff tendinopathy, and platelet-rich plasma (PRP) injections have become a viable regenerative therapeutic approach.  Regarding PRP's effectiveness in treating rotator cuff tendinopathies, previous research has shown contradictory findings. In comparison to alternative therapies like collagen or corticosteroid injections, the purpose of this systematic review was to assess the impact of PRP injections on pain and functional results in rotator cuff tendinopathy and partial rotator cuff tears. Methods: We searched the PubMed, EMBASE, Cochrane Library, and Scopus databases for randomised controlled trials (RCTs) including PRP injections in rotator cuff tendinopathy. The search (from January 2020 to March 2025) followed PRISMA guidelines. Inclusion criteria were RCTs involving adults with rotator cuff tendinosis or partial tears, comparing PRP to any control (corticosteroids , collagen). Three reviewers independently screened studies and extracted data on patient characteristics, intervention details, follow-up duration, pain and shoulder function outcomes, and adverse events. The risk of bias was assessed using Cochrane criteria. Outcomes were synthesized qualitatively due to heterogeneity in comparators and outcome measures across studies. A PRISMA flow diagram (Figure 1) summarizes study selection. Results: Four RCTs (total≈300 shoulders) met inclusion criteria after screening 100 full-text articles (Figure 1). Three trials compared PRP to corticosteroid injections, and one trial compared PRP (alone or with collagen) to collagen injections. Follow-up ranged from 3 months to 12 months. In short-term follow-up (6 weeks to 3 months), patients who received PRP showed greater pain relief and functional improvement than those who received corticosteroid injections in two RCTs. For example, one trial reported significantly better improvement in pain visual analog scale (VAS) and shoulder scores at 3 months with PRP vs. steroid (VAS improvement: –13.6 vs +0.4 points), and another noted superior short-term pain and range-of-motion gains with PRP. In mid- to long-term follow-up, findings were mixed. At 12 months, one high-quality RCT showed that a single subacromial PRP injection led to significantly greater improvements in pain (final VAS 1.68 vs 2.3) and shoulder function (ASES score 89.8 vs 78.0; SANE 89.2 vs 80.5) compared to a corticosteroid injection. However, another RCT found no significant differences between PRP and steroid by 1 year despite early benefits. The trial comparing PRP to collagen found no significant differences in pain or disability scores between the groups through 6 months. Safety: No serious adverse events were reported with PRP. PRP recipients commonly experienced transient localized pain or soreness after injection, whereas steroid injections were associated with 2–3 cases of mild allergic reactions in one study. Conclusions: PRP injection is a safe treatment option for rotator cuff tendinopathy that yields comparable or better short-term outcomes than corticosteroid injections, with some evidence of sustained benefit at one-year follow-up. PRP did not demonstrate clear superiority over collagen injections in partial rotator cuff tears. Given the risk profile of corticosteroids (e.g. potential tendon degeneration), PRP may be preferable in patients for whom steroids are contraindicated or ineffective. Nevertheless, heterogeneity among studies and mixed long-term results indicate that the overall efficacy of PRP remains inconclusive. Further large-scale RCTs with standardized PRP preparations and inclusion of appropriate control groups (e.g. placebo or exercise therapy) are warranted to clarify the long-term clinical role of PRP in rotator cuff tendinopathy.