"Stem cell therapy" for OA is a broad marketing umbrella covering many different biological products — from bone marrow concentrate to adipose-derived cells to exosomes. They differ substantially in composition, mechanism, regulatory status, and evidence. This page presents the current state of evidence honestly.
ACR/AF 2019: Strongly recommended against stem cell and mesenchymal cell injection therapies for osteoarthritis. OARSI 2019: Level 5, strongly not recommended — highest uncertainty, lowest evidence category. AAOS: Not addressed in knee OA clinical practice guidelines. NICE NG226: Not addressed.
Major categories: Bone marrow aspirate concentrate (BMAC) — autologous, drawn from the patient's iliac crest; most studied. Adipose-derived stromal vascular fraction (SVF) — autologous cells from liposuction; more invasive. Allogenic mesenchymal stem cells — from donor sources (umbilical cord, bone marrow); many lack FDA approval for OA. Exosomes and secretome — very early-stage; often marketed without clinical data.
Approximately 28 trials have been published, of which only 8 are placebo-controlled, totaling approximately 467 patients across the controlled studies. For BMAC and SVF: some positive early-phase trials, generally with favorable safety profiles. However: small sample sizes, short follow-up, no standardized cell products, very limited sham-controlled data. Phase III trials are limited. Many commercial "stem cell" offerings go beyond what any published trial has studied.
LDRT includes multiple RCTs — including sham-controlled positive trials (Fazilat-Panah 2025, LoRD-KNeA 2025) — large single-center series (Koneru 2024, 2025; Ojo 2026), a 10-year randomized follow-up (Makarova 2025), and the 2026 ARS AUC multispecialty consensus. Response rate: 60–90%. LDRT's evidence base is substantially larger and more rigorous than what is available for most regenerative therapies for OA.
Regenerative therapies for OA are almost universally self-pay. Medicare and most commercial plans classify them as experimental. Out-of-pocket costs: $5,000–$50,000+. There is no correlation between price and evidence quality. LDRT is accessible through academic medical centers; multiple institutions report Medicare and commercial plan coverage at a fraction of the cost of most regenerative programs.
What exactly is being injected, and what is its source? What is the FDA regulatory status for this specific product and indication? What peer-reviewed clinical trial evidence exists for this specific product in osteoarthritis? What are the full out-of-pocket costs?
Related: All comparisons | LDRT vs. PRP | Am I a candidate?
Medically reviewed by: Robert Warren Floyd, M.D., Ph.D. — Resident Physician, Radiation Oncology, The University of Texas MD Anderson Cancer Center. Last reviewed: August 2, 2026. Independent personal project — not affiliated with or endorsed by MD Anderson Cancer Center. Funding & independence disclosure.