Healing & Recovery
What Is the Evidence for PRP in Tendon Injury?
The short answer
The largest sham-controlled trial ever run on PRP injections for tendon pain — 240 patients with chronic Achilles tendinopathy — found no meaningful difference from a fake injection at 6 months. A 2022 meta-analysis of 33 randomized trials across six tendon conditions found PRP injections outperformed comparators in only one of them, carpal tunnel syndrome. But PRP looks more useful in a different role: as a surgical adjunct. A meta-analysis of 17 randomized trials found PRP used during rotator cuff surgery lowered the structural retear rate from 25.4% to 19.3%. The evidence for PRP as a standalone injection and PRP as a surgical augmentation point in different directions, and that gap is unresolved.
Quick answers
- What is it?
- Platelet-rich plasma (PRP) is a treatment that concentrates a patient's own blood platelets and injects them into an injured tendon to try to speed healing.
- Why are people interested in it?
- PRP injections are widely marketed for tendon pain and sports injuries, so people want to know if the biggest trials actually back that up.
- What has actually been studied?
- The largest sham-controlled randomized trial (240 patients with chronic Achilles tendinopathy), a 2022 meta-analysis of 33 randomized trials across six tendon conditions, a meta-analysis comparing PRP to corticosteroids, and a meta-analysis of PRP used during rotator cuff surgery.
- How strong is the evidence?
- Mixed and site-dependent: the largest sham-controlled trial found no benefit over a fake injection, and most tendon conditions showed no clear benefit either, but PRP used as a surgical adjunct during rotator cuff repair measurably reduced retear rates.
- What don't we know yet?
- Why PRP looks weak as a standalone injection but stronger as a surgical adjunct, which PRP formulation matters, whether any benefit persists beyond 12 months, and which patients, if any, respond reliably.
- Where can I read the original research?
- Sources at the bottom of this page: Kearney RS, Ji C, Warwick J, et al., JAMA, 2021; and Masiello F, Pati I, Veropalumbo E, et al., Blood Transfusion, 2022.
The short answer: Platelet-rich plasma has one of the more extensively randomized-trial-tested track records of any regenerative treatment for tendon injury — and the results are genuinely mixed. The largest, best-designed sham-controlled trial, published in JAMA in 2021, found a single PRP injection performed no better than a placebo injection for chronic Achilles tendinopathy. A 2022 meta-analysis of 33 trials across six tendon conditions found a clear PRP benefit in only one of them. But when PRP is used differently — stitched into a surgical rotator cuff repair rather than injected alone — a separate meta-analysis found it measurably reduced the rate of the repair tearing again.
What the research shows
The largest sham-controlled trial found no benefit
The single strongest piece of evidence on PRP injections for tendon pain is a 2021 multicenter randomized trial published in JAMA. Researchers at 24 sites enrolled 240 adults with chronic midportion Achilles tendinopathy — tendon pain confirmed by imaging and present for more than 3 months — and randomized them to a single intratendinous PRP injection or a sham injection (a needle inserted under the skin but not into the tendon). At 6 months, the primary outcome — the VISA-A tendon function score, where higher is better and the minimal clinically important difference is 12 points — was 54.4 in the PRP group versus 53.4 in the sham group, an adjusted difference of -2.7 points (95% CI, -8.8 to 3.3). The trial's conclusion was direct: PRP "did not reduce Achilles tendon dysfunction" compared with a fake injection. Adverse events, mostly injection-site discomfort and swelling, were similar between groups. DOI
Across most tendon conditions, PRP injections don't clearly beat the alternatives
A 2022 systematic review and meta-analysis in the journal Blood Transfusion pooled 33 randomized trials covering 2,025 patients across six different tendinopathies: lateral epicondylitis (8 trials), plantar fasciitis (5), Achilles tendinopathy (5), rotator cuff tendinopathy (7), patellar tendinopathy (3), and carpal tunnel syndrome (5). PRP was compared against steroid injections, saline, whole blood, local anesthetic, dry needling, prolotherapy, bone-marrow stem cells, or non-injection care. Across lateral epicondylitis, plantar fasciitis, Achilles, rotator cuff, and patellar tendinopathy, the review found "no clear between-group differences" in pain or function at short-, medium-, or long-term follow-up. The one exception was carpal tunnel syndrome, where PRP recipients had significantly better pain and symptom-severity scores than controls at multiple time points. The authors rated the overall certainty of evidence as low or very low across comparisons, citing risk of bias, imprecision, and inconsistency between trials. DOI
A narrower 2021 meta-analysis of nonoperative treatments for lateral epicondylitis (tennis elbow) reached a similar conclusion for that specific condition: pooling 2 randomized trials comparing PRP against control, the researchers found no significant difference in either pain or function. DOI
PRP versus corticosteroids: a mid-term edge that fades
A different comparison — PRP against corticosteroid injections rather than placebo — produced a more favorable, if still qualified, picture. A 2025 meta-analysis in BMC Musculoskeletal Disorders pooled 27 randomized trials covering 1,779 patients across rotator cuff injury, lateral epicondylitis, plantar fasciitis, and tenosynovitis. At 1 month, there was generally no significant difference between PRP and corticosteroid. By 3 to 6 months, PRP showed statistically significant advantages in several conditions — better pain scores in rotator cuff injury at 3 months, better pain and function scores in plantar fasciitis at 6 months, and better pain and disability scores in lateral epicondylitis at 3 and 12 months. The authors concluded PRP's "mid-term efficacy is superior to that of corticosteroids" but that "long-term efficacy remains to be further clinically verified." DOI
A different story when PRP augments surgery instead of standing alone
The evidence looks more consistent when PRP is used not as a standalone injection but as an adjunct during surgical tendon repair. A 2021 meta-analysis in Arthroscopy pooled 17 randomized trials evaluating PRP products used during arthroscopic rotator cuff repair surgery. Pooling all trial types, the retear rate — assessed by follow-up imaging — was 19.3% in the PRP-augmented group versus 25.4% in controls (odds ratio 0.59, P=.0037). When broken down by PRP formulation, pure platelet-rich plasma (without added leukocytes) showed the strongest effect (odds ratio 0.26, P=.0005). PRP augmentation was also associated with significantly better Constant, visual analog pain, and Simple Shoulder Test scores compared to surgery without PRP. DOI This is a structurally different question than the JAMA Achilles trial — it asks whether PRP helps a surgically repaired tendon stay intact, not whether it heals a degenerated tendon on its own.
What we don't know yet
Why PRP looks weak as a standalone injection but stronger as a surgical adjunct. No published study directly explains this discrepancy; it may reflect differences in the underlying tissue biology (a surgically repaired tendon versus a chronically degenerated one) or simply reflect which comparisons happen to be well-powered.
Which PRP formulation matters. The rotator cuff surgery meta-analysis found pure PRP outperformed leukocyte-rich formulations, but few trials directly compare formulations head-to-head across other tendon conditions.
Whether any benefit persists beyond 12 months. Most trials, including the corticosteroid comparison, stop follow-up well before the one-year mark; long-term durability is explicitly flagged as unresolved in the review literature itself.
Which patients, if any, respond reliably. No trial identified in this search pre-specified or validated patient characteristics that predict PRP response.
Whether injection technique or timing changes outcomes. The JAMA trial used a single injection; other trials in the broader literature use multiple injections on varying schedules, and head-to-head comparisons of protocol are limited.
Sources
- Kearney RS, Ji C, Warwick J, et al. Effect of Platelet-Rich Plasma Injection vs Sham Injection on Tendon Dysfunction in Patients With Chronic Midportion Achilles Tendinopathy: A Randomized Clinical Trial. JAMA, 2021;326(2):137-144. DOI
- Masiello F, Pati I, Veropalumbo E, Pupella S, Cruciani M, De Angelis V. Ultrasound-guided injection of platelet-rich plasma for tendinopathies: a systematic review and meta-analysis. Blood Transfusion, 2022;21(2):119-136. DOI
- Lapner P, Alfonso A, Hebert-Davies J, Pollock JW, Marsh J, King GJW. Nonoperative treatment of lateral epicondylitis: a systematic review and meta-analysis. JSES International, 2021;6(2):321-330. DOI
- Ye Z, Yuan Y, Kuang G, Qiu L, Tan X, Wen Z, Lu M. Platelet-rich plasma and corticosteroid injection for tendinopathy: a systematic review and meta-analysis. BMC Musculoskeletal Disorders, 2025;26(1):339. DOI
- Ryan J, Imbergamo C, Sudah S, Kirchner G, Greenberg P, Monica J, Gatt C. Platelet-Rich Product Supplementation in Rotator Cuff Repair Reduces Retear Rates and Improves Clinical Outcomes: A Meta-analysis of Randomized Controlled Trials. Arthroscopy, 2021;37(8):2608-2624. DOI
Article records maintained via PubMed. Peptide Proof reports what studies found. It does not provide medical advice, dosing guidance, or treatment recommendations.
Topic: Recovery & Tissue Research
Sources
- Effect of Platelet-Rich Plasma Injection vs Sham Injection on Tendon Dysfunction in Patients With Chronic Midportion Achilles Tendinopathy: A Randomized Clinical Trial
- JAMA, 2021 · n=240 · DOI
- Ultrasound-guided injection of platelet-rich plasma for tendinopathies: a systematic review and meta-analysis
- Blood Transfusion, 2022 · n=2025 · DOI
- Nonoperative treatment of lateral epicondylitis: a systematic review and meta-analysis
- JSES International, 2021 · DOI
- Platelet-rich plasma and corticosteroid injection for tendinopathy: a systematic review and meta-analysis
- BMC Musculoskeletal Disorders, 2025 · n=1779 · DOI
- Platelet-Rich Product Supplementation in Rotator Cuff Repair Reduces Retear Rates and Improves Clinical Outcomes: A Meta-analysis of Randomized Controlled Trials
- Arthroscopy, 2021 · DOI
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