PRP, a blood-based shot, has different results by body part

Knee wear often brings stiffness after sitting

Knee arthritis can bring aching after a walk, swelling later, or stiffness when you rise after a meal or some reading. Stairs may trouble you more.

Guided strength work, a well-fitted brace, and smaller changes in activity may ease the strain on your knee. Medicine belongs in a talk with your doctor.

After twelve months, the largest careful trial found no extra relief from PRP over saline, though other reviews favored it over some shots at selected times. It isn't an automatic first choice.

Groin soreness and outer-hip soreness have different causes

A deep groin ache may come from the hip joint, while outer-hip soreness may begin in a tendon near it. That cord connects a muscle to a bone.

Hip-joint studies found that PRP didn't ease pain more than saline, but those studies don't answer every outer-hip problem. An exam can tell the two areas apart.

In Peoria, QC Kinetix offers biologic therapies, meaning the clinic separates your blood after a clinician examines the exact place that hurts. The clinician can then explain the blood-based option offered.

Shoulder soreness changes with the movement you make

Reaching overhead, fastening clothes, or lying on the sore side may bring shoulder pain. Sudden weakness after an injury needs quicker care.

A sore shoulder tendon may hurt when you lift your arm, reach for a shelf, or carry a bag. Rest alone may not rebuild strength.

A PRP study on one tendon can't answer questions about another tendon. Your advice should match the movement that hurts and the part found on exam.

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. 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.

6. 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.

7. 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.

8. The 2019 ACR/Arthritis Foundation osteoarthritis guideline makes STRONG recommendations for exercise, weight loss in people with overweight or obesity, self-management programmes, tai chi, cane use, tibiofemoral bracing, topical and oral NSAIDs and intra-articular glucocorticoid injections for knee OA. Its conditional recommendations cover balance exercises, yoga, CBT, acupuncture, thermal modalities, radiofrequency ablation, acetaminophen, duloxetine and tramadol. Anything offered before a course of the strongly recommended options is being offered out of order.

   Kolasinski SL, Neogi T, Hochberg MC, et al. — 2019 American College of Rheumatology/Arthritis Foundation Guideline for the Management of Osteoarthritis of the Hand, Hip, and Knee. Arthritis & Rheumatology, 2020. DOI: 10.1002/art.41142.

9. 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.