PRP, the blood-based shot, does not help every joint

An X-ray cannot measure how much you hurt

An X-ray may show arthritis in a joint that causes little soreness, while a mild-looking joint can hurt greatly. Your daily limits matter too.

Less soreness isn't proof that the smooth cartilage over bone ends has returned. Be wary when an ad promises that change.

An exam, your X-ray, and the tasks you miss give the clinician more useful information than any one of them alone. No single result chooses the care.

Knee studies disagree, while hip studies show little help

Platelet-rich plasma is shortened to PRP; it is made by separating blood and saving plasma with many platelets, small blood cells involved in clotting. Results depend on the sore body part.

In the largest careful knee study, both groups improved, but PRP did no better than saline after twelve months; other reviews favored PRP at certain times. Hip studies found no clear pain relief over saline.

After your exam, QC Kinetix offers regenerative treatments, meaning the clinic may prepare a blood-based option once the clinician has checked the sore area and heard your concerns. You can ask whether PRP is reasonable.

Severe wear may still call for a surgery talk

PRP may be discussed before some operations, but it doesn't replace every operation. Severe wear, weakness, or lost movement can change the advice.

You can ask what delay might mean and what recovery from surgery would involve. The answer should cover each choice's limits.

There is time to take the first conversation home before you choose. You can weigh soreness, cost, recovery, family needs, and the activities you miss.

Sources

1. 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. DOI: 10.1001/jama.2021.19415.

2. A Bayesian network meta-analysis restricted to LARGE randomized trials (at least 100 patients per group; 57 trials, 22,795 participants, 18 intra-articular interventions) found treatment effects were larger in the 35 high-risk-of-bias trials than in the 22 low/unclear-risk trials. Excluding high-risk trials, the effects of 16 of the 18 intra-articular interventions in knee or hip OA were smaller than the minimal clinically important difference and most were consistent with placebo effects; triamcinolone had the highest probability of exceeding the MID at weeks 2-6.

   Pereira TV, Saadat P, Bobos P, et al. — Effectiveness and safety of intra-articular interventions for knee and hip osteoarthritis based on large randomized trials: A systematic review and network meta-analysis. Osteoarthritis and Cartilage, 2025. DOI: 10.1016/j.joca.2024.08.014.

3. 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. DOI: 10.1097/CORR.0000000000003349.

4. A network meta-analysis of 11 randomized trials (1353 patients) with HIP osteoarthritis found that for both pain and function, at 2-4 months and at 6 months, NO intervention - corticosteroid, hyaluronic acid or PRP - significantly outperformed an intra-articular saline placebo injection.

   Gazendam A, Ekhtiari S, Bozzo A, et al. — Intra-articular saline injection is as effective as corticosteroids, platelet-rich plasma and hyaluronic acid for hip osteoarthritis pain: a systematic review and network meta-analysis of randomised controlled trials. British Journal of Sports Medicine, 2021. DOI: 10.1136/bjsports-2020-102179.

5. The devices used to spin PRP at the point of care are cleared by FDA as clinical centrifuges, product code JQC, a Class I device under 21 CFR 862.2050 - for example the Biomet GPS Platelet Separation Kit (K030555, cleared 2003) and the Harvest SmartPrep2 / SmartPrep Platelet Concentration System (K103340, cleared 2010). That clearance covers the equipment that separates blood. It is not an FDA approval of platelet-rich plasma as a treatment for osteoarthritis, tendinopathy or any other orthopedic condition, and copy must never blur the two.

   U.S. Food and Drug Administration (Center for Devices and Radiological Health) — 510(k) Premarket Notification database and Product Classification: JQC, Centrifuges (Micro, Ultra, Refrigerated) For Clinical Use, 21 CFR 862.2050. FDA accessdata (CDRH device databases), 2003.

6. A systematic review of 105 clinical PRP studies in orthopaedics published 2006-2016 found that only 11 (10%) described the preparation protocol clearly enough for another investigator to repeat it, and only 17 (16%) reported any quantitative metric of the final PRP composition. The authors concluded that the current reporting of PRP preparation and composition does not allow the PRP products actually delivered to patients to be compared between studies.

   Chahla J, Cinque ME, Piuzzi NS, et al. — A Call for Standardization in Platelet-Rich Plasma Preparation Protocols and Composition Reporting: A Systematic Review of the Clinical Orthopaedic Literature. Journal of Bone and Joint Surgery (American), 2017. DOI: 10.2106/JBJS.16.01374.

7. 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. DOI: 10.1002/14651858.CD010071.pub3.

8. A systematic review and meta-analysis with best-worst case analysis found statistically NON-significant evidence that PRP with or without physical therapy reduced mean time to return to play or reinjury rates for hamstring injuries compared with no treatment or physical therapy alone, in short-term follow-up. Complication rates (postinjection discomfort, pain or sciatic nerve irritation) averaged 5.2% +/- 2.9%. The pooled picture does not support the single positive trial.

   Seow D, Shimozono Y, Tengku Yusof TNB, et al. — Platelet-Rich Plasma Injection for the Treatment of Hamstring Injuries: A Systematic Review and Meta-analysis With Best-Worst Case Analysis. American Journal of Sports Medicine, 2021. DOI: 10.1177/0363546520916729.

9. The ESSKA-ICRS consensus applied the RAND/UCLA appropriateness method to 216 clinical scenarios for intra-articular PRP in knee OA. Only 84 scenarios (38.9%) were rated appropriate, 9 (4.2%) inappropriate and 123 (56.9%) uncertain. PRP was judged appropriate in patients aged 80 or under with KL grade 0-III osteoarthritis AFTER failed conservative non-injective or injective treatment; it was NOT considered appropriate as a first treatment, nor in KL grade IV (bone-on-bone) osteoarthritis, where 91.7% and 87.5% of scenarios respectively were uncertain.

   Kon E, de Girolamo L, Laver L, et al. — Platelet-rich plasma injections for the management of knee osteoarthritis: The ESSKA-ICRS consensus. Recommendations using the RAND/UCLA appropriateness method for different clinical scenarios. Knee Surgery, Sports Traumatology, Arthroscopy, 2024. DOI: 10.1002/ksa.12320.

10. The Cochrane review of STEM CELL injections for knee osteoarthritis concluded that on low-certainty evidence they may slightly improve pain and function, with uncertainty about effects on quality of life, treatment success and structural progression, and uncertainty about safety. This matters on a PRP site because 'stem cell therapy' is routinely used as a marketing label for PRP; they are different products with different evidence and PRP must never be described as a stem cell treatment.

    Whittle SL, Johnston RV, McDonald S, et al. — Stem cell injections for osteoarthritis of the knee. Cochrane Database of Systematic Reviews, 2025. DOI: 10.1002/14651858.CD013342.pub2.

11. FDA states verbatim of stem cell, stromal vascular fraction, umbilical cord blood, Wharton's jelly, amniotic fluid and exosome products: 'None of these products have been approved for the treatment of any orthopedic condition, such as osteoarthritis, tendonitis, disc disease, tennis elbow, back pain, hip pain, knee pain, neck pain, or shoulder pain.' The only FDA-approved stem cell products in the United States are blood-forming cells from umbilical cord blood, approved only for disorders of blood production, and there are no FDA-approved exosome products. PRP is a different product from all of these and the categories must not be blurred in either direction.

    U.S. Food and Drug Administration — Consumer Alert on Regenerative Medicine Products Including Stem Cells and Exosomes. FDA (Center for Biologics Evaluation and Research), 2020.