PRP evidence by body area: might it ease my soreness?

What did knee studies find?

Movement and strength exercises can help the muscles carry more of the load. That may ease soreness during walking or standing. The amount and kind of exercise need to suit your knee. Pain that rises and stays higher means the exercise needs changing.

Studies of PRP for knee arthritis give mixed answers. Some found less soreness or easier movement than gel or steroid treatments. One large study reported no better soreness or joint result than salt water. PRP may help some knees, but the studies don't promise it.

Have the examiner explain the old images and knee findings. Then ask whether the hoped-for result is less soreness, better motion, or easier walking. Find out what PRP cannot repair in a worn joint. You need a result you can notice in daily life.

Did PRP help the heel, elbow, or bottom of the foot?

Tendons are sturdy cords that fasten muscles to bones. Repeated pulling can make one of these cords sore. Easing the painful load, then building strength slowly, often helps it recover. The place that hurts decides which study matters.

Achilles tendon studies found no less soreness or better use than salt-water treatment. Some elbow studies found better later relief than steroid treatment. The plantar fascia is the thick band under your foot. Some studies found PRP helped this band more than steroid treatment after the early weeks.

Have the person examining you point out the sore tendon or band. Then ask how exercise will be used during care. If PRP is offered for your heel, elbow, or foot, request a study about that named area. Research about another tendon won't answer your question.

What did shoulder, hip, ankle, and back studies find?

Shoulder studies give mixed answers. One found brief relief and better arm use compared with steroid treatment. A different study found PRP no better than salt water when both groups exercised. Ask whether your sore shoulder tendon matches the people who were studied.

For arthritis inside the hip, studies found PRP no better than gel or salt water. Sore tendons outside the hip are a different problem. One study found longer help from PRP than from steroid treatment for those tendons. Your exam needs to say whether the soreness starts inside or outside the joint.

An ankle study found PRP no better than salt water. Back studies are few and small, so their answer remains uncertain. Ask which part of your back seems sore and what exam or image supports that answer. Then request research about the same back problem.

Why does the prepared blood matter?

Platelets are small blood cells that gather at a cut and help start repair. Concentrated PRP has a greater share of platelets than your usual blood. The prepared blood may keep or remove many white blood cells. Clinics don't all prepare it alike.

These differences matter because past studies used many kinds of prepared blood. Ask how many platelets the clinic puts into the joint or tendon. Also ask whether many white blood cells remain. Then request research using similar blood for your body part.

A clinic may not have a firm answer for every detail. Research still hasn't settled which blood preparation works for each problem. Ask about remaining care if PRP doesn't ease enough soreness. You need both the hoped-for result and the next choice explained.

Evidence sources

1. A clinical-recommendations review graded PRP indication by indication: good evidence for leukocyte-poor PRP in knee osteoarthritis; moderate-to-high-quality evidence for leukocyte-rich PRP in patellar tendinopathy and for PRP in plantar fasciitis; INSUFFICIENT evidence to routinely recommend PRP for rotator cuff tendinopathy, hip osteoarthritis or high ankle sprains; and demonstrated LACK of efficacy for Achilles tendinopathy, muscle injuries, acute fracture or non-union, and as a surgical augment in rotator cuff repair, Achilles repair and ACL reconstruction.

   Le ADK, Enweze L, DeBaun MR, et al. — Current Clinical Recommendations for Use of Platelet-Rich Plasma. Current Reviews in Musculoskeletal Medicine, 2018.

2. In the RESTORE trial - the largest placebo-controlled PRP trial in knee osteoarthritis - 288 adults aged 50+ with symptomatic Kellgren-Lawrence grade 2-3 medial knee OA received three weekly intra-articular injections of leukocyte-poor PRP from a commercial system or saline placebo. At 12 months the mean change in knee pain was -2.1 points with PRP versus -1.8 with saline (difference -0.4; 95% CI -0.9 to 0.2; P=.17) against a minimum clinically important difference of 1.8, and the change in medial tibial cartilage volume was -1.4% versus -1.2% (difference -0.2%; 95% CI -1.9% to 1.5%; P=.81). Twenty-nine of 31 prespecified secondary outcomes showed no significant between-group difference. The authors concluded the findings do not support use of PRP for knee OA.

   Bennell KL, Paterson KL, Metcalf BR, et al. — Effect of Intra-articular Platelet-Rich Plasma vs Placebo Injection on Pain and Medial Tibial Cartilage Volume in Patients With Knee Osteoarthritis: The RESTORE Randomized Clinical Trial. JAMA, 2021.

3. In a double-blind, placebo-controlled trial of 54 patients with chronic midportion Achilles tendinopathy, all doing eccentric exercises, VISA-A scores improved 21.7 points with PRP and 20.5 points with saline over 24 weeks - an adjusted between-group difference of -0.9 (95% CI -12.4 to 10.6), excluding the predefined relevant difference of 12 points. PRP added nothing to eccentric loading.

   de Vos RJ, Weir A, van Schie HT, et al. — Platelet-rich plasma injection for chronic Achilles tendinopathy: a randomized controlled trial. JAMA, 2010.

4. A 24-site, 240-patient participant-blinded randomized trial of a single intratendinous PRP injection versus a sham (subcutaneous dry needle) for chronic midportion Achilles tendinopathy found VISA-A scores of 54.4 versus 53.4 at six months (adjusted mean difference -2.7; 95% CI -8.8 to 3.3) against a 12-point minimal clinically important difference. The authors stated the findings do not support the use of this treatment for chronic midportion Achilles tendinopathy.

   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.

5. PATH-2 randomised 230 adults with acute Achilles tendon rupture managed non-surgically to PRP or a placebo dry-needle injection across 19 UK hospitals, with a central laboratory confirming the PRP was of good quality with the expected growth-factor content. At 24 weeks there was no detectable difference in muscle-tendon function (limb symmetry index 34.7% versus 38.5%; adjusted mean difference -3.9%; 95% CI -10.5% to 2.7%) or in any secondary outcome or adverse-event rate.

   Keene DJ, Alsousou J, Harrison P, et al. — Platelet rich plasma injection for acute Achilles tendon rupture: PATH-2 randomised, placebo controlled, superiority trial. BMJ, 2019.

6. A 12-centre randomized controlled trial of 230 patients with chronic lateral epicondylar tendinopathy compared tendon needling with leukocyte-enriched PRP against tendon needling alone. At 12 weeks there was no significant difference (55.1% versus 47.4% pain improvement; P=.163). At 24 weeks the PRP group reported 71.5% versus 56.1% pain improvement (P=.019), a 83.9% versus 68.3% success rate (P=.037), and significantly less residual elbow tenderness (29.1% versus 54.0%; P=.009). No significant complications occurred in either group.

   Mishra AK, Skrepnik NV, Edwards SG, et al. — Efficacy of platelet-rich plasma for chronic tennis elbow: a double-blind, prospective, multicenter, randomized controlled trial of 230 patients. American Journal of Sports Medicine, 2014.

7. A systematic review and meta-analysis of nine randomized trials (239 PRP patients, 240 corticosteroid patients) in chronic plantar fasciitis found statistically significant differences in VAS pain favouring PRP at 1-1.5, 3, 6 and 12 months, and in AOFAS function favouring PRP at 6 and 12 months (no difference at 1 and 3 months).

   Hurley ET, Shimozono Y, Hannon CP, et al. — Platelet-Rich Plasma Versus Corticosteroids for Plantar Fasciitis: A Systematic Review of Randomized Controlled Trials. Orthopaedic Journal of Sports Medicine, 2020.

8. A multicentre, double-blinded, placebo-controlled trial randomised 100 patients with ankle (tibiotalar) osteoarthritis to two ultrasound-guided intra-articular injections of PRP or placebo. Symptom scores improved by 10 points with PRP and 11 points with placebo, an adjusted between-group difference over 26 weeks of -1 (95% CI -6 to 3; P=.56). The authors concluded the results do not support the use of PRP injections for ankle osteoarthritis.

   Paget LDA, Reurink G, de Vos RJ, et al. — Effect of Platelet-Rich Plasma Injections vs Placebo on Ankle Symptoms and Function in Patients With Ankle Osteoarthritis: A Randomized Clinical Trial. JAMA, 2021.

9. A meta-analysis of six randomized trials (211 PRP patients, 197 hyaluronic acid patients, mean follow-up about 12 months) in hip osteoarthritis found NO significant difference between PRP and hyaluronic acid in weighted improvement on WOMAC, VAS or Harris Hip Score - including in a subanalysis isolating leukocyte-poor PRP.

   Belk JW, Houck DA, Littlefield CP, et al. — Platelet-Rich Plasma Versus Hyaluronic Acid for Hip Osteoarthritis Yields Similarly Beneficial Short-Term Clinical Outcomes: A Systematic Review and Meta-analysis of Level I and II Randomized Controlled Trials. Arthroscopy, 2022.

10. A prospective, double-blind randomized controlled study of intradiscal PRP for chronic (6 months or more) lumbar discogenic pain unresponsive to conservative treatment found participants receiving PRP had significant improvements in Functional Rating Index, NRS best pain and NASS satisfaction at 8 weeks compared with controls, with FRI improvement maintained through at least one year. No disc-space infection, neurologic injury or progressive herniation was reported. The authors called for further work to define which patients respond and what the ideal injectate is.

    Tuakli-Wosornu YA, Terry A, Boachie-Adjei K, et al. — Lumbar Intradiskal Platelet-Rich Plasma (PRP) Injections: A Prospective, Double-Blind, Randomized Controlled Study. PM&R, 2016.

11. The Cochrane review of platelet-rich therapies for musculoskeletal soft-tissue injuries concluded there is currently insufficient evidence to support the use of platelet-rich therapy for treating musculoskeletal soft tissue injuries, overall and for individual conditions - including pooled data from six trials of PRP applied during rotator cuff repair surgery, which showed no statistically or clinically significant long-term functional difference. The review ended with an explicit call for standardisation of PRP preparation methods.

    Moraes VY, Lenza M, Tamaoki MJ, et al. — Platelet-rich therapies for musculoskeletal soft tissue injuries. Cochrane Database of Systematic Reviews, 2014.

12. An updated meta-analysis of six randomized trials (422 patients) found no benefit of PRP over placebo for Achilles tendinopathy on VISA-A at 3 months (mean difference 1.7; 95% CI -1.8 to 5.2), 6 months (0.5; 95% CI -8.5 to 9.3) or 1 year (-7.9; 95% CI -27.3 to 11.6), nor on VAS pain at 3 months. Funnel-plot asymmetry suggested publication bias inflating apparent benefits. The authors wrote that PRP should not be used to treat Achilles tendinopathy until high-quality trials show a clear clinical benefit.

    Barreto ESR, Antunes Junior CR, Silva IC, et al. — Is Platelet-rich Plasma Effective in Treating Achilles Tendinopathy? A Meta-analysis of Randomized Clinical Trials. Clinical Orthopaedics and Related Research, 2025.