# Common questions about a sore joint *Questions Answered | biologic therapy mesa* > Straight answers to biologic therapy Mesa questions about soreness, PRP, urgent signs, cost, and clinic visits. This page answers common joint-care questions in plain words. The answers cover relief, warning signs, time, and cost. I'd take the questions that apply to your joint to the next visit. You don't need to remember clinic terms. Ask the examiner to explain anything that isn't clear. ## Sources 1. The 2025 Cochrane review of stem cell injections for knee osteoarthritis pooled 25 randomised trials (1,341 participants) and found that, compared with placebo injection, stem cell injection MAY slightly improve pain (1.2 points better on a 0-10 scale, 7 studies, 445 participants) and function (14.2 points better on a 0-100 scale, 7 studies, 432 participants) up to six months - both rated LOW-certainty evidence, downgraded for indirectness (cell source, preparation and dose varied across studies) and suspected publication bias, since up to three larger RCTs were conducted and withdrawn before reporting results. Radiographic progression was not assessed in any included study. Whittle SL, et al. — [Stem cell injections for osteoarthritis of the knee.](https://pubmed.ncbi.nlm.nih.gov/40169165/). *Cochrane Database of Systematic Reviews*, 2025. DOI: 10.1002/14651858.CD013342.pub2. 2. RESTORE, the largest and most rigorously blinded placebo-controlled PRP trial in knee OA (n=288, participant-, injector- and assessor-blinded), gave three weekly injections of a commercial leukocyte-poor PRP or saline. At 12 months the change in knee pain was -2.1 vs -1.8 points (difference -0.4; 95% CI -0.9 to 0.2; P=.17) and the change in medial tibial cartilage volume was -1.4% vs -1.2% (difference -0.2%; P=.81). Twenty-nine of 31 prespecified secondary outcomes showed no between-group difference. The authors concluded the findings do not support the use of PRP for knee OA. Bennell KL, 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. 3. The largest head-to-head trial of cell-based orthobiologics to date randomised 480 patients with KL II-IV knee OA across four arms: autologous bone marrow aspirate concentrate, autologous adipose stromal vascular fraction, allogeneic umbilical cord tissue-derived MSCs, and a corticosteroid injection control. At 12 months NONE of the three orthobiologic injections was superior to another or to the corticosteroid control on either co-primary endpoint (VAS pain, KOOS pain), and none of the four groups showed a significant change in MRI osteoarthritis score from baseline. No procedure-related serious adverse events were reported. Mautner K, et al. — [Cell-based versus corticosteroid injections for knee pain in osteoarthritis: a randomized phase 3 trial.](https://pubmed.ncbi.nlm.nih.gov/37919438/). *Nature Medicine*, 2023. DOI: 10.1038/s41591-023-02632-w. 4. FDA states verbatim of stem cell products, stromal vascular fraction (adipose-derived cells), 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 (hematopoietic progenitor) cells derived from umbilical cord blood, approved only for disorders of blood production, and there are currently NO FDA-approved exosome products. U.S. Food and Drug Administration — [Consumer Alert on Regenerative Medicine Products Including Stem Cells and Exosomes](https://www.fda.gov/vaccines-blood-biologics/consumers-biologics/consumer-alert-regenerative-medicine-products-including-stem-cells-and-exosomes). *FDA (Center for Biologics Evaluation and Research)*, 2020. 5. In a within-patient placebo-controlled trial, 25 people with BILATERAL knee osteoarthritis received bone marrow aspirate concentrate in one knee and saline in the other, acting as their own controls. Pain scores fell significantly from baseline in BOTH knees at 1 week, 3 months and 6 months, and the relief - described by the authors as dramatic - did not differ significantly between the BMAC knee and the saline knee. Shapiro SA, et al. — [A Prospective, Single-Blind, Placebo-Controlled Trial of Bone Marrow Aspirate Concentrate for Knee Osteoarthritis.](https://pubmed.ncbi.nlm.nih.gov/27566242/). *American Journal of Sports Medicine*, 2017. DOI: 10.1177/0363546516662455. 6. A cross-sectional study contacted 273 of 317 US centres offering direct-to-consumer stem-cell therapy, posing as a 57-year-old man with knee osteoarthritis. The mean advertised price of a unilateral same-day stem-cell knee injection was $5,156 (SD $2,446; 95% CI $4,550-5,762, n=65) and the mean claimed clinical efficacy was 82% (SD 9.6%; n=36) - a figure the authors describe as a gap between marketing claims and the published literature. Piuzzi NS, et al. — [The Stem-Cell Market for the Treatment of Knee Osteoarthritis: A Patient Perspective.](https://pubmed.ncbi.nlm.nih.gov/28738432/). *Journal of Knee Surgery*, 2018. DOI: 10.1055/s-0037-1604443. 7. In January 2025 federal district court orders resolving a joint FTC and Georgia Attorney General complaint permanently BANNED the co-founders of the Stem Cell Institute of America and several related companies from marketing stem cell therapy, and required payment of $5,155,146 in civil penalties and consumer refunds. In March 2024 the court had granted summary judgment on all counts, finding the defendants created and published false and misleading advertisements about the efficacy of stem cell injections. The affiliated clinic charged up to $5,000 per injection, almost exclusively to elderly and disabled consumers. Federal Trade Commission — [Stem Cell Institute Co-Founders and Companies Banned from Marketing Stem Cell Treatments and Ordered to Pay More Than $5.1 Million for Refunds and Civil Penalties](https://www.ftc.gov/news-events/news/press-releases/2025/01/stem-cell-institute-co-founders-companies-banned-marketing-stem-cell-treatments-ordered-pay-more-51). *FTC Press Release*, 2025. 8. FDA's patient and consumer notice on regenerative medicine states that it has received reports of BLINDNESS, TUMOUR FORMATION, neurological events, bacterial infections including life-threatening blood infections, unwanted immune reactions, and cells migrating and forming unintended tissue, following the use of unapproved regenerative medicine products - a list that explicitly includes stromal vascular fraction, amniotic fluid, Wharton's jelly, ortho-biologics and exosomes. It also warns that a product's presence on clinicaltrials.gov, or a firm's registration with FDA, does NOT mean the product is legally marketed. U.S. Food and Drug Administration — [Important Patient and Consumer Information About Regenerative Medicine Therapies](https://www.fda.gov/vaccines-blood-biologics/consumers-biologics/important-patient-and-consumer-information-about-regenerative-medicine-therapies). *FDA (Center for Biologics Evaluation and Research)*, 2021. ## Why does my knee still hurt after rest? Rest may settle soreness that has grown worse, but too much sitting adds stiffness. The knee can hurt again when you stand or put weight on it. Try easy movement that doesn't cause a sharp jab. If swelling or lost sleep continues, arrange an exam. ## Does PRP, made from my own blood, rebuild knee cartilage? Less soreness doesn't prove that new cartilage formed. PRP is the shortened form of platelet-rich plasma. Spinning your blood collects extra platelets in one part. Platelets are small pieces in blood that help a clot form. Ask whether the aim is relief or a change in the joint itself. ## How long can PRP relief last? Relief doesn't follow one set timetable for every person or joint. Ask what daily change the office expects and when someone will check it. Also ask about the choices if soreness returns sooner than you hoped. ## What does a PRP visit involve? The office draws a little blood from your arm. A machine spins the blood and gathers the part with more platelets for the shot. Ask about the appointment length, driving home, and which later soreness needs a call. ## When does joint soreness need urgent care? A fever with a hot, red, swollen joint calls for prompt help. Get quick care after an injury when the joint looks bent or won't bear weight. Sudden weakness matters too. These changes can't wait for a regular visit. ## Are biologic injections shots made from blood or body tissue? Yes, the term covers shots prepared using blood or tissue from a body. Ask exactly what will be used, its source, and who does the procedure. Have the total price and likely visit count put in writing. At QC Kinetix, you may discuss regenerative treatments after a medical provider checks the joint; the term means these office procedures, and you'll want to ask whether a doctor does yours. ## A first visit can sort out your next step Tell them when the ache first appeared, which motion starts it, and what it keeps you from doing. Ask about the exam, full price, recovery time, and who takes later calls. Mesa residents can use Dobson Road or Loop 202 toward Chandler. Call (602) 837-PAIN before leaving. A visit can help you weigh choices, but your outcome can't be promised. Book a free consultation: --- Clear help for a sore joint. Plain help with a sore joint, care at home, office visits, and choices besides surgery. Plain Mesa help for aching joints, care at home, and office visits. This site is operated by the owners of the QC Kinetix Phoenix-area clinics, including the Chandler and Scottsdale locations described in this guide, and those owners benefit when a reader books a consultation. © 2026 Mesa Biologic Field Guide. General health education only; a clinician who examines you should guide decisions about your own joint.