# What do people ask about a sore joint? *Questions About Your Joint | joint injections phoenix* > Straight answers for joint injections phoenix readers about relief, PRP, cost, surgery, blood sugar, and when to seek care. The joint can ache all day, catch during one motion, or stiffen after rest. Treatment names pile up quickly. Plain answers aren't always easy to find. I'll tell you where the facts stop. Studies can't promise your result. A fever together with a very warm, swollen joint needs in-person care, not another web answer. ## Sources 1. The 2015 Cochrane review of 27 trials (1,767 participants) found intra-articular corticosteroid better than sham for knee OA pain (SMD -0.40, 95% CI -0.58 to -0.22; NNTB 8), but the benefit decayed with time: moderate at 1-2 weeks, small at 13 weeks, and no evidence of any effect at 26 weeks. All outcomes were graded LOW quality. Jüni P, et al. — [Intra-articular corticosteroid for knee osteoarthritis.](https://pubmed.ncbi.nlm.nih.gov/26490760/). *Cochrane Database Syst Rev*, 2015. DOI: 10.1002/14651858.CD005328.pub3. 2. A 2022 BMJ systematic review and meta-analysis of 169 trials (21,163 participants) found viscosupplementation produced only a small pain reduction versus placebo (SMD -0.08, 95% CI -0.15 to -0.02; about -2.0 mm on a 100 mm VAS), below the minimal clinically important difference, and trial sequential analysis indicated conclusive evidence of clinical equivalence with placebo since 2009. Pereira TV, et al. — [Viscosupplementation for knee osteoarthritis: systematic review and meta-analysis.](https://pubmed.ncbi.nlm.nih.gov/36333100/). *BMJ*, 2022. DOI: 10.1136/bmj-2022-069722. 3. The RESTORE randomized trial (288 participants, leukocyte-poor PRP, 3 weekly injections) found no significant difference from saline placebo at 12 months in knee pain (-2.1 vs -1.8 points; difference -0.4, 95% CI -0.9 to 0.2) or in medial tibial cartilage volume (-1.4% vs -1.2%), with 29 of 31 secondary outcomes also showing no between-group difference. 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. 4. FDA's HCT/P guidance sets out the minimal-manipulation and homologous-use criteria that decide whether a human cell or tissue product is regulated solely under 21 CFR Part 1271 (section 361) or requires a biologics licence; cell-based orthopaedic injections that fall outside those criteria are unapproved drugs and biological products, and no cell-based product is FDA-approved to treat osteoarthritis. U.S. Food and Drug Administration — [Regulatory Considerations for Human Cells, Tissues, and Cellular and Tissue-Based Products: Minimal Manipulation and Homologous Use - Guidance for Industry and FDA Staff](https://www.fda.gov/regulatory-information/search-fda-guidance-documents/regulatory-considerations-human-cells-tissues-and-cellular-and-tissue-based-products-minimal). *U.S. Food and Drug Administration*, 2020. 5. The 2025 Cochrane living review of stem cell injections for knee OA (25 trials, 1,341 participants) found stem cell injection MAY slightly improve pain and function up to six months versus placebo (pain 1.2 points better on a 0-10 scale; function 14.2 points better on 0-100), but rated the evidence LOW certainty for both, downgraded for indirectness and suspected publication bias, with up to three larger RCTs withdrawn before reporting results. Whittle SL, et al. — [Stem cell injections for osteoarthritis of the knee.](https://pubmed.ncbi.nlm.nih.gov/40169165/). *Cochrane Database Syst Rev*, 2025. DOI: 10.1002/14651858.CD013342.pub2. ## Do cortisone shots work? They may ease a sore knee for a short time. Relief is often strongest during the first several weeks, then fades. That may help you sleep or walk more easily. It doesn't mean you'll get the same result. ## How long does a gel injection last in your knee? No one can give you a sure length. Some people report relief for months, but large reviews found little extra help on average. Get the expected number of appointments and their total cost. Also find out what you'll try if your knee doesn't improve. ## Is PRP nonsense? A flat yes or no isn't fair. PRP is the short name for platelet-rich plasma. The clinic spins a blood sample and saves liquid rich in tiny pieces called platelets. They normally help stop bleeding and start healing. Some studies reported more relief with PRP than with steroid or gel. One large study found no useful added relief over plain salt water used for comparison. Clinics don't always leave equal amounts of platelets and germ-fighting white cells in that liquid, so results are hard to compare. ## What is the new injection instead of knee replacement? No joint procedure replaces surgery for everyone. Steroid and gel are shots. For PRP, the clinic spins your blood and uses the saved liquid. Marrow concentrate comes from marrow taken from your pelvis and spun down. These choices may ease soreness, but they can't rebuild every worn joint. Replacement may make more sense when damage is severe and movement is poor. ## How much are joint injections in Phoenix? There isn't one honest price for everyone. Cost changes with the treatment, number of visits, x-rays or scans, and insurance. Insurance often pays for steroid, though gel coverage varies. You'll often pay cash for PRP or prepared marrow. Get the full price before you book. ## How soon after a cortisone shot can I have surgery? Tell your surgeon the date of each recent joint procedure. A steroid shot during the three months before replacement may raise the chance of infection around the new joint. Your surgeon needs to choose the timing because your health and planned operation both matter. ## What happens when someone checks the joint? At the visit, describe the first sore day and each motion that now sets it off. The clinician can examine your joint and review your medicine. They might also look at an x-ray, ultrasound, or another scan. Then you can discuss choices that don't involve surgery. Ask about cost, risk, likely relief, and what you'll do if the first choice doesn't help. Bring your questions. That's what the visit is for. Book a free consultation: --- Your joint hurts. Let's talk about what may help. Why your joint may ache, what can settle it at home, when an exam is worth it, and which office may be easiest to reach. Clear facts on soreness, common choices, safety, and Phoenix clinic routes. This site is operated by the owners of the QC Kinetix Phoenix-area clinics, including the locations it recommends, and the business may benefit when readers book a consultation. Copyright 2026 Phoenix Joint Evidence. General education only; not medical advice or a diagnosis for any individual joint.