# Does PRP work for a sore joint? *Does PRP Work? | PRP Injections Phoenix* > Does PRP work? Read clear findings for knee, hip, and tendon soreness from this PRP injections Phoenix guide. Does PRP work? It may ease some soreness, but results vary by joint. You can’t count on a result. A machine divides your blood for platelet-rich plasma, or PRP. Staff retain a portion with extra platelets. These blood cells help a cut clot and begin repair. ## What to know about knee results Knee arthritis has the most PRP research. Some reviews found better results than hyaluronic acid, a gel used for knees. People reported less soreness and easier movement. A careful knee study used harmless salt water for comparison. It didn’t find PRP better for soreness. It didn’t find less cartilage loss either. Cartilage is the smooth covering on bone ends. Studies haven’t shown that PRP rebuilds this covering. Ask about easier walking or less soreness instead. ## What to ask during a visit QC Kinetix uses trained health professionals, called medical providers, for exams and clinic care. They discuss regenerative care, meaning non-surgical options made from your blood. PRP is one option. Tell the provider which motion starts your soreness. Ask why research on your knee, hip, or tendon—the tissue joining muscle and bone—applies. You’ll also want to hear what else you can try. Don’t accept a result borrowed from another body part. A knee isn’t an elbow. Your exam and earlier care still matter. ## How to judge a clear answer For tennis elbow, some reviews found steroid helped sooner while PRP helped later. Achilles tendon studies found no clear gain over salt water. Hip studies aren’t as common as knee studies. PRP can contain more or fewer white blood cells. Machines don’t leave the same platelet amount. Research hasn’t proved one mixture fits everyone. Ask how your blood will be prepared. Ask when you may notice a change. They’ll need to admit PRP might not help. ## 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](https://pubmed.ncbi.nlm.nih.gov/34812863/). *JAMA*, 2021. DOI: 10.1001/jama.2021.19415. 2. A meta-analysis of 18 Level I randomized trials (811 patients receiving PRP, 797 receiving hyaluronic acid, mean follow-up 11.1 months) found mean improvement in total WOMAC scores was significantly higher with PRP (44.7%) than with hyaluronic acid (12.6%) (P<.01), and 6 of 11 VAS-reporting studies found significantly less pain with PRP at latest follow-up. Belk JW, Kraeutler MJ, Houck DA, et al. — [Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials](https://pubmed.ncbi.nlm.nih.gov/32302218/). *American Journal of Sports Medicine*, 2021. DOI: 10.1177/0363546520909397. 3. 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](https://pubmed.ncbi.nlm.nih.gov/39265924/). *Osteoarthritis and Cartilage*, 2025. DOI: 10.1016/j.joca.2024.08.014. 4. A meta-analysis of 73 articles covering 5,895 patients quantified the PLACEBO response to intra-articular injection in knee osteoarthritis: statistically and clinically significant improvements in pain, function and quality of life at 1, 3 and 6 months, with responder rates above 50% at each of those points, declining by 12 months. The placebo response was stronger in trials with more female participants and in more recently published trials. This is why an uncontrolled 'our patients improved' figure carries almost no information. Previtali D, Boffa A, Di Laura Frattura G, et al. — [Placebo response to intra-articular injections in knee osteoarthritis: magnitude, evolution over time, and influencing factors. A systematic review and meta-analysis with meta-regression](https://pubmed.ncbi.nlm.nih.gov/41031623/). *EFORT Open Reviews*, 2025. DOI: 10.1530/EOR-2025-0022. 5. The AAOS third-edition clinical practice guideline for non-arthroplasty management of knee osteoarthritis contains 29 recommendations, and the work group explicitly identified intra-articular corticosteroid, hyaluronic acid AND platelet-rich plasma as areas needing better research - including osteoarthritis characterisation, severity stratification, clinically relevant outcomes with controls for bias, and cost-effectiveness analysis. PRP is presented as an open research question in this guideline, not as a settled treatment. Brophy RH, Fillingham YA — [AAOS Clinical Practice Guideline Summary: Management of Osteoarthritis of the Knee (Nonarthroplasty), Third Edition](https://pubmed.ncbi.nlm.nih.gov/35383651/). *Journal of the American Academy of Orthopaedic Surgeons*, 2022. DOI: 10.5435/JAAOS-D-21-01233. 6. 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](https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPCD/classification.cfm?ID=JQC). *FDA accessdata (CDRH device databases)*, 2003. 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](https://pubmed.ncbi.nlm.nih.gov/29040132/). *Journal of Bone and Joint Surgery (American)*, 2017. DOI: 10.2106/JBJS.16.01374. 8. The American Academy of Physical Medicine and Rehabilitation convened a technical expert panel that ran a structured literature review (2023, updated through June 2025) and a modified Delphi process, and issued five evidence-based clinical recommendations plus 11 consensus-based best practices for PRP in knee osteoarthritis. The statement is explicit that orthobiologic therapies 'remain an evolving area of practice' and that robust, dose-dependent randomized controlled trials are still needed to establish PRP's clinical effects. Borg-Stein J, Jayaram P, Colorado BS, et al. — [AAPM&R guidance statement on platelet rich plasma for knee osteoarthritis](https://pubmed.ncbi.nlm.nih.gov/41989317/). *PM&R*, 2026. DOI: 10.1002/pmrj.70144. 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](https://pubmed.ncbi.nlm.nih.gov/38961773/). *Knee Surgery, Sports Traumatology, Arthroscopy*, 2024. DOI: 10.1002/ksa.12320. ## Bring notes about your sore joint QC Kinetix offers PRP and other non-surgical choices through its Phoenix-area clinics. Write down your medicines, earlier care, and the motions that hurt. Banner Estrella may suit west Phoenix. Scottsdale may be closer from the east. Call (602) 837-PAIN to confirm the clinic and current schedule. Book a free consultation: --- Find the cause. Choose your next step. Plain answers about aching joints, PRP, prices, safety and care nearby. Help with Phoenix joint soreness, PRP questions, and nearby care. This site is operated by the owners of the QC Kinetix Phoenix-area clinics, including the locations serving Banner Estrella, Scottsdale, Peoria and Chandler. © 2026 Phoenix PRP Field Notes. General education only; a medical provider should assess your individual situation.