Recent studies give mixed answers about joint procedures

A large knee study found no clear winner among the tested procedures

A large 2023 knee study compared three cell products with a familiar steroid shot. After twelve months, none was better on the main soreness scores.

The study result doesn't mean nobody improved, because people in all four groups reported change. The costly products did not beat the comparison treatment.

Another review found that people often improve after a joint procedure even without the active product. Natural ups and downs and care around the visit can affect reports.

What does the study mean for you? Improvement after a procedure doesn't prove the product caused the improvement.

The 2023 finding came from knees, so it cannot answer a shoulder or hip question. Results shown for one product also don't settle the results for another.

Gentle movement still helps on an ordinary sore day

Gentle movement can ease stiffness and keep the muscles around your joint working. A short walk or familiar exercise may be enough on a sore day.

More work isn't better when the joint is already irritated. Ease back for a short time without stopping all movement.

Warmth before activity may loosen a stiff area, while cold afterward may ease swelling. Either choice needs to feel soothing and leave your skin unharmed.

Stop an exercise that causes sharp pain or leaves you worse the next day. A physical therapist can adjust movement for your strength and balance.

Severe swelling or sudden weakness needs prompt medical care

Fever with a hot, badly swollen joint can mean infection. Seek urgent medical care instead of waiting for a regular office visit.

New loss of bladder control matters when it comes with back pain, leg weakness, or numbness. Bladder loss with back or leg symptoms may point to pressure on nearby nerves.

Soreness after extra activity is usually less urgent. Arrange an exam when the ache keeps returning or starts disturbing sleep and walking.

The doctor may check the sore joint, muscle strength, and feeling in nearby areas. The joint and nerve exam separates a common flare from a warning sign.

Sources

1. In a 480-patient, four-arm, multicenter randomized phase 2/3 trial, none of three orthobiologic cell injections - autologous bone marrow aspirate concentrate, autologous adipose stromal vascular fraction, or allogeneic umbilical cord tissue-derived mesenchymal stromal cells - was superior to any other, or to a corticosteroid injection control, on pain at 12 months.

   Mautner K, et al. — Cell-based versus corticosteroid injections for knee pain in osteoarthritis: a randomized phase 3 trial. Nat Med, 2023. DOI: 10.1038/s41591-023-02632-w.

2. On 27 September 2024 the Ninth Circuit held in United States v. California Stem Cell Treatment Center that stromal vascular fraction produced by enzymatically digesting a patient's own fat IS a drug under the Federal Food, Drug, and Cosmetic Act, and that the same surgical procedure exception does not apply because the removed fat and the implanted SVF are not the same thing. The district court's ruling for the clinics was reversed.

   United States Court of Appeals for the Ninth Circuit — United States v. California Stem Cell Treatment Center, Inc., No. 22-56014 (9th Cir. Sept. 27, 2024). , 2024.

3. On 18 December 2024 FDA approved RYONCIL (remestemcel-L-rknd), the first mesenchymal stromal cell therapy ever approved in the United States - for steroid-refractory acute graft-versus-host disease in pediatric patients 2 months and older, given as eight intravenous infusions. It is not an orthopedic product and does not make any joint injection approved.

   US Food and Drug Administration — FDA Approves First Mesenchymal Stromal Cell Therapy to Treat Steroid-refractory Acute Graft-versus-host Disease. , 2024.

4. A 2025 systematic review and meta-analysis of 8 randomized trials in 502 patients found intra-articular mesenchymal stem cells improved WOMAC scores versus control at 6 months (MD 7.44, 95% CI 1.45-13.42) and 12 months (MD 10.31, 95% CI 0.96-19.67), with wide confidence intervals and a small pooled sample.

   Cao M, et al. — Efficacy and safety of mesenchymal stem cells in knee osteoarthritis: a systematic review and meta-analysis of randomized controlled trials. Stem Cell Res Ther, 2025. DOI: 10.1186/s13287-025-04252-2.

5. A 2025 systematic review and meta-analysis of 6 randomized trials found microfragmented adipose tissue and PRP both reached the minimal clinically important difference on most outcomes to 12 months, with no clear superiority of the fat-derived preparation despite its higher price.

   Park YB, et al. — Microfragmented Adipose Tissue as an Alternative to Platelet-Rich Plasma for Intra-articular Injection in Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Am J Sports Med, 2025. DOI: 10.1177/03635465251337759.

6. A 2025 meta-analysis of 73 double-blind placebo-controlled injection trials in 5,895 knee osteoarthritis patients found placebo responder rates above 50 percent at 1, 3 and 6 months, declining by 12 months - which is why any uncontrolled 'our patients improved' claim from a clinic is uninterpretable.

   Previtali D, 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. EFORT Open Rev, 2025. DOI: 10.1530/EOR-2025-0022.

7. A double-blind placebo-controlled trial of allogeneic culture-expanded adipose MSCs in stage III knee osteoarthritis kept blinding for 12 months and followed the treatment arm to 60 months, reporting only mild transient adverse events - but only 29 subjects completed, 8 of them in the placebo arm.

   Jafar H, et al. — Intra-articular allogeneic adipose-derived mesenchymal stromal cell injections for stage III knee osteoarthritis: a double-blind placebo-controlled trial with 60-month follow-up. Stem Cells Transl Med, 2026. DOI: 10.1093/stcltm/szag018.

8. A 2025 randomized trial of 66 knee osteoarthritis patients compared a single adipose stromal vascular fraction injection, conventional rehabilitation alone, and the two combined over 12 months - a design that treats exercise-based rehabilitation as a genuine comparator rather than an afterthought.

   Lu J, et al. — Intraarticular injection of the stromal vascular fraction for the treatment of knee osteoarthritis a prospective randomized controlled clinical trial. Sci Rep, 2025. DOI: 10.1038/s41598-025-09398-w.