What to know before choosing a knee shot

Ask what each choice can and can't do

A cortisone shot often works sooner than the other choices. Its effect can fade with time. It doesn't rebuild the worn parts of your knee. Ask your doctor about the risks of more shots.

Gel is meant to act like joint fluid. People don't all feel the same result from it. Ask how long you would wait before judging it. Also ask what you would do if it didn't help.

For PRP, staff draw blood much like a routine blood test. A machine spins it and gathers more platelets into less liquid. Clinics don't all prepare PRP alike. Ask how this clinic prepares yours.

Try the basics before deciding

A shot isn't the only way to ease a sore knee. Gentle exercise can help you keep strength and motion. Weight loss can reduce load when it applies to you. Bracing or a cane may help with daily walking.

Describe which of these you've tried. Say how long each helped, if it helped at all. Take along the medicine list plus surgery dates. Those details can change which choice makes sense.

Choose after an exam, not from a product name. You can't know whether joint trouble explains the soreness yet. Until then, keep activity easy and avoid anything that sharply worsens it.

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.. Cochrane Database Syst Rev, 2015. DOI: 10.1002/14651858.CD005328.pub3.

2. In a 2-year double-blind RCT of 140 patients with symptomatic knee OA and ultrasound synovitis, 40 mg intra-articular triamcinolone every 12 weeks produced significantly greater cartilage volume loss than saline (index compartment cartilage thickness change -0.21 mm vs -0.10 mm; between-group difference -0.11 mm, 95% CI -0.20 to -0.03) with no significant difference in knee pain.

   McAlindon TE, et al. — Effect of Intra-articular Triamcinolone vs Saline on Knee Cartilage Volume and Pain in Patients With Knee Osteoarthritis: A Randomized Clinical Trial.. JAMA, 2017. DOI: 10.1001/jama.2017.5283.

3. 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.. BMJ, 2022. DOI: 10.1136/bmj-2022-069722.

4. 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.. JAMA, 2021. DOI: 10.1001/jama.2021.19415.

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.. Cochrane Database Syst Rev, 2025. DOI: 10.1002/14651858.CD013342.pub2.

6. 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. U.S. Food and Drug Administration, 2020.

7. The 2019 ACR/Arthritis Foundation OA guideline makes a STRONG recommendation for intra-articular glucocorticoid injection in knee OA, alongside strong recommendations for exercise, weight loss, self-management, tai chi, cane use, bracing and NSAIDs; intra-articular steroid injection for HAND OA is only conditionally recommended.

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