Stem Cell Therapy for Knees and Knee Osteoarthritis: Results by KL Grade, Cost & Who Qualifies (2026)

When Conservative Care Stops Working — Beyond NSAIDs, HA, and Cortisone

You have probably worked through the conservative ladder already. NSAIDs help, but five years of daily use shows up in your kidneys and stomach. Hyaluronic acid felt useful for a year, then noticeably less. Steroid shots clear the flare but cannot be repeated frequently. Your orthopedist mentions a total knee replacement (TKA), but you are 60, you travel, you ski, and 6–12 weeks of recovery plus a 15-year implant lifespan are not the answer you wanted.

This is exactly the gap that stem cell therapy occupies — between symptom management that has plateaued and a major operation that may be overkill. The 2025 Cao meta-analysis confirmed not only short-term pain reduction (6-month WOMAC MD=7.44, P=0.01) but durable function improvement at 12 months (MD=10.31, P=0.03), with adipose-derived cells outperforming bone-marrow cells. That durability is what NSAIDs and HA cannot offer.

Stem cell therapy is not a guarantee, and it is not for everyone. But for the right patient — early to moderate disease, motivated, willing to travel for two visits about 7 weeks apart — it is the most evidence-supported non-surgical option available today. And while weight management and low-impact exercise help protect the cartilage you still have, there is no proven way to regenerate knee cartilage naturally once it is worn away — which is why, for cartilage repair without surgery in early-to-moderate disease, biologically active options such as autologous stem cell therapy matter.

Doctors classify knee OA severity using the Kellgren-Lawrence (KL) system based on X-ray findings:

Stem cell therapy achieves the best outcomes for patients with KL Grade II–III OA, where sufficient cartilage remains for the stem cells to support repair. Even some Grade IV patients experience meaningful pain relief.

If cortisone or gel injections have already stopped helping, our companion guide lists every remaining option — PRP, culture-expanded cells, GAE, bracing, osteotomy — with the trial evidence for each and the point at which surgery becomes the better choice:

What Is Stem Cell Therapy for Knees and Knee Osteoarthritis?

Knee osteoarthritis is the gradual breakdown of the protective cartilage covering the ends of the femur and tibia, with thickening of underlying bone, inflammation of the joint lining, and progressive pain, stiffness, and loss of motion. Approximately 240 million people worldwide live with this disease, and 33% of adults over the age of 75 have both symptomatic and radiographic knee osteoarthritis, as documented in the 2021 review published in JAMA (Katz, Arant, and Loeser 2021).

The goal of stem cell therapy is biological disease modification at the joint level, not only symptom suppression. Unlike hyaluronic acid (which lubricates) or PRP (which delivers growth factors for several days), stem cells continuously release a cocktail of anti-inflammatory cytokines and trophic growth factors for weeks — which is why they sit on a different shelf of the treatment ladder.

A 2025 meta-analysis of 502 patients across 8 randomized controlled trials, published in Stem Cell Research & Therapy (Cao, Ou, Sheng et al. 2025), confirmed that intra-articular MSC injection alone — without surgery — significantly improves WOMAC pain and function scores at both 6 and 12 months. The treatment is appropriate for Kellgren-Lawrence Grade I-III osteoarthritis, with strongest evidence in Grade II-III. For Grade IV bone-on-bone disease, stem cells can offer meaningful pain relief but cannot rebuild a structurally collapsed joint.

How Stem Cells Repair Knee Cartilage — The 4 Mechanisms

Understanding why stem cells do something a drug cannot helps you set realistic expectations. The four mechanisms below are documented in mechanistic reviews and clinical trials.

Anti-Inflammatory Action — Calming Joint Inflammation

The first mechanism is the rapid suppression of joint inflammation. Mesenchymal stem cells secrete anti-inflammatory cytokines including IL-10, TGF-β, and PGE2, which quiet the pro-inflammatory cascade driving osteoarthritis pain. This effect begins within days and is sustained for weeks, as detailed in the 2020 mechanistic review published in Trends in Pharmacological Sciences (Song, Scholtemeijer, and Shah 2020).

Cartilage Protection and Repair — Can Knee Cartilage Grow Back?

The second mechanism is cartilage protection and regenerative signaling. MSCs release trophic factors that support chondrocyte (cartilage cell) survival and stimulate matrix production, while reducing the catabolic enzymes (MMPs, aggrecanases) that degrade cartilage. A 2023 review of 26 clinical studies (15 RCTs plus 11 non-RCTs, totaling 610 patients) published in Cellular & Molecular Immunology (Copp, Robb, and Viswanathan 2023) documented cartilage protection or repair in 18 of 21 clinical studies. Stem cells do not rebuild a fully collapsed joint, but they preserve and modestly regenerate cartilage thickness in early-to-moderate disease.

Immune System Regulation — Long-Term Joint Homeostasis

The third mechanism is immune modulation — MSCs reprogram the local joint immune environment from a pro-inflammatory state to a homeostatic one. This explains the durability of effect: even after the injected cells are cleared, the local immune landscape remains better regulated for months, per the same 2023 Copp et al. analysis.

Sustained Pain Relief — 12+ Months Documented

The fourth mechanism is the sustained downstream effect on pain. The 2025 Cao meta-analysis confirmed significant WOMAC pain score improvement at both 6 and 12 months. A separate 5-year follow-up study published in Stem Cells Translational Medicine (Kim, Lee, Kim et al. 2022) demonstrated that a single intra-articular high-dose (1×10⁸ cells) autologous ADMSC injection provided pain and functional improvement maintained for 5 years.

Does Stem Cell Therapy Work for Knees? What the 2025 Cochrane Review and RCTs Actually Show

Two things in that table deserve a plain-language translation. First, the direction of the evidence is positive: across placebo-controlled trials, patients who received stem cell injections reported less pain, better function and more often called the treatment a success. Second, the authors downgraded their confidence for a specific reason — indirectness. The trials pooled different products (bone marrow, adipose, umbilical cord), different preparation methods (same-day concentrates vs culture-expanded cells) and doses ranging from a few million to over 100 million cells. A meta-analysis that mixes those together can only tell you that “stem cell injections, on average, may help a little.” It cannot tell you what a high-dose, culture-expanded, autologous adipose-derived protocol does. For that, you need the trials that isolate those variables — which is what the next evidence layer provides.

Culture-Expanded MSCs at High Dose: The 2025 Cao Meta-Analysis

The Cao et al. 2025 meta-analysis is the strongest current evidence summary. It pooled 8 RCTs of 502 knee osteoarthritis patients who had not received any surgical treatment. The intervention was intra-articular injection of MSCs without any other adjuvant therapy. Across the full pooled cohort, MSC-treated patients showed statistically significant improvement over control at both 6 and 12 months in total WOMAC, WOMAC subscales (pain, stiffness, function), and 100-mm VAS pain score.

Equally important is what the meta-analysis found about safety: adverse events did not differ significantly between MSC and control groups (P=0.21), and serious adverse events also did not differ (P=0.69). For a regenerative therapy in 2025, this is a meaningful signal. Combined with a 5-year follow-up by Kim et al. 2022 showing no treatment-related adverse events across 5 years post-injection, the safety profile of autologous ADSC therapy is at least as favorable as conventional intra-articular treatments.

Read together, Cochrane and Cao point in the same direction. Cochrane says stem cell injections probably help but the trials are too heterogeneous to be confident; Cao, restricting the analysis to culture-expanded mesenchymal stem cells given without surgery, finds significant 6- and 12-month improvement, larger effects for adipose-derived than bone-marrow cells, and a clear dose–response with 100 million cells as the threshold. The practical conclusion for a patient is not “stem cells work” or “stem cells don’t work.” It is: the product, the dose and your KL grade decide the outcome — and those are the three things you should ask any clinic about before you pay.

Not All “Stem Cell” Knee Injections Are the Same: Cultured Autologous ADSC vs Same-Day BMAC/SVF vs Birth-Tissue Products

Tissue of origin. The 2025 Cao subgroup data favor adipose. Adipose-derived cells are easier to harvest (a brief outpatient procedure rather than a bone marrow aspirate), more abundant per gram of tissue, and produced the statistically significant 6-month WOMAC effect that bone-marrow MSCs did not in the pooled analysis. A 2024 randomized study published in Journal of Translational Medicine (Sun, Zhai, Han et al. 2024) added a biological explanation: outcomes of autologous AD-MSC therapy correlate with each patient’s own cell stemness and senescence markers — which is what passage-limited culture is designed to preserve.

Same-day vs cultured. A same-day concentrate is fast and inexpensive, but nobody counts the stem cells in it. Mesenchymal stem cells are a tiny fraction of the nucleated cells in bone marrow or fat, and a 2018 systematic review of 46 clinical BMAC studies published in The Journal of Bone and Joint Surgery (Piuzzi et al. 2018) found that no study described its preparation well enough to be reproduced and only 30% reported what was actually in the final product. Culture expansion exists to solve that problem: it turns an unknown number of cells into a counted, characterized dose.

Birth-tissue products. Amniotic fluid, amniotic membrane and umbilical cord products are widely marketed in the United States as “stem cell injections.” When independent laboratories cultured commercial amniotic fluid products under the same conditions that grow bone-marrow MSCs, they could not identify mesenchymal stem cells in any of them, and the few living cells present did not have MSC characteristics (Panero et al. 2019, American Journal of Sports Medicine). A Cornell University analysis of a cord blood product found the cells were primarily leukocytes and no stem cells were present (Fortier et al. 2021). These products may still carry growth factors, but they are not stem cell therapy. If a clinic offers a “stem cell” injection without a fat or marrow harvest from you, ask what is in the syringe.

Outcomes by Kellgren-Lawrence Grade — I, II, III, and IV

KL Grade I-II — Early Disease — Best Long-Term Outcomes

For early-stage KL I-II disease, stem cell therapy is ideally positioned. The cartilage is thinning but still functional, the joint structure is preserved, and the regenerative environment is most responsive. Patients in this range typically experience the largest long-term benefit. Combined with weight management and targeted exercise, KL I-II patients can often delay or entirely avoid surgical intervention.

KL Grade III — Moderate Disease — Strongest RCT Evidence

KL Grade III is the grade where stem cell therapy has the strongest Phase III randomized controlled trial evidence. A 2023 Phase III, multicenter, double-blind, placebo-controlled trial (NCT03990805) of 261 patients with KL Grade 3 symptomatic knee osteoarthritis, published in The American Journal of Sports Medicine (Kim, Lee, Lee et al. 2023), showed that a single intra-articular injection of autologous culture-expanded ADMSCs produced significantly greater 100-mm VAS pain reduction (25.2 vs 15.5, P=.004) and total WOMAC improvement (21.7 vs 14.3, P=.002) than placebo at the 6-month primary endpoint, with no serious treatment-related adverse events.

KL Grade IV (Bone-on-Bone) — When Stem Cells Help and When Surgery Is Better

At KL Grade IV, stem cells will not rebuild the joint. What they can offer is meaningful pain reduction and functional improvement — particularly valuable for patients who cannot undergo TKA because of age, comorbidities, anticoagulation requirements, or personal preference. For surgical candidates with severe deformity, surgical cartilage replacement or total knee replacement remains the better long-term choice. For non-surgical candidates, stem cell therapy is the most effective non-surgical pain-and-function intervention currently supported by 2025 meta-analytic data.

A Published Case: KL Grade III Knee, VAS 8→0 and JOA 55→95 at 13 Months (Cureus 2026)

Why one case matters — and what it cannot tell you. A single patient cannot prove a treatment works; that is what the randomized trials above are for. What a published case adds is transparency: the cell count, viability, plan number and follow-up were reported in a peer-reviewed, open-access journal that anyone can read. Few clinics that market stem cell injections publish their outcomes at all.

How Many Stem Cells Do You Need? Why 100 Million Is the Threshold

Why dose matters biologically is straightforward: stem cells exert their effects through paracrine signaling — molecules released into the joint at concentrations proportional to cell number. Below a threshold dose, the signaling cascade is too weak to durably modulate the inflammatory and reparative environment. The Cao 2025 subgroup analysis quantified this for the first time in pooled data.

This is also why early Phase I dose-escalation work added important nuance. The 2016 Phase I trial published in Stem Cells Translational Medicine (Pers, Rackwitz, Ferreira et al. 2016) randomized 18 patients with severe knee osteoarthritis to three dose cohorts (2 million, 10 million, or 50 million autologous adipose-derived stem cells) and found that even low-dose patients experienced significant WOMAC improvement at 6 months, with no serious adverse events across all cohorts. The takeaway is not “more is always better at any dose” — it is “100 million is the threshold below which the 2025 meta-analytic data become marginal.” Cell Grand Clinic guarantees a minimum of 100 million quality-verified ADSCs per knee treatment.

Stem Cell Therapy vs Knee Replacement vs PRP vs Hyaluronic Acid: Which Fits Your Knee?

For a full comparison of every non-surgical option by KL grade, see our guide to alternatives to knee replacement when injections stop working. For meniscus tears specifically, see stem cell therapy for a torn meniscus.

What to Expect: Fat Harvest → 7-Week Culture → Injection → Follow-Up

Note: Repeat treatments may be recommended depending on disease severity.

How Much Does Stem Cell Therapy for Knees Cost? Japan vs USA vs Mexico vs Panama

What is not included: travel and accommodation for two visits to Osaka (about 3 days each), the online consultation (JPY 55,000 per person, credited toward treatment), and any optional bridge treatment (exosome or PRP) at Visit 1. Stem cell therapy for knee osteoarthritis is not covered by Japanese public insurance or by most overseas insurers.

Why a “cheap” injection can cost more: a USD 5,000 same-day injection that delivers an uncounted number of cells and needs to be repeated is not necessarily cheaper than one counted, high-dose treatment. When comparing quotes, ask for the cell type, the number of cells, the viability at injection and what happens if the first injection is insufficient. Cell Grand Clinic prices a repeat session from stored cells at the same rate as the first session, and cells can be stored for up to five years. Full details are on our pricing page.

Risks, Side Effects, and Who Should — and Should Not — Have Stem Cell Knee Injections

Known and possible risks. Common and temporary: pain, swelling or bruising at the fat harvest site and in the injected knee for a few days; a transient flare of knee pain after injection. Uncommon: infection at either site, including septic arthritis; allergic reaction to local anesthetic; bleeding in patients on anticoagulants. Theoretical: the Cochrane authors note that the long-term risks of injecting cells with the capacity to grow remain unknown at the population level; in autologous, passage-limited cultured cells, tumor formation has not been reported in the trials cited on this page, and no serious treatment-related adverse events were recorded in the Phase III RCT (Kim 2023) or the 5-year follow-up (Kim 2022).

Who should not be treated. Cell Grand Clinic does not treat patients who are HIV-positive; active infection, active cancer under treatment, and uncontrolled diabetes or anticoagulation are assessed individually and may postpone treatment. KL grade IV knees with significant deformity in a patient who is a surgical candidate are usually better served by knee replacement. There is no fixed upper age limit: patients in their 80s have been treated, and the 7-week culture allows older patients’ cells to reach the full dose within the passage-3 limit.

This therapy is particularly effective for:

• Kellgren-Lawrence Grade II-III OA: Patients with moderate degeneration typically see the best outcomes
• Hyaluronic acid, steroid injections, or PRP no longer provide lasting relief
• Active individuals: Those who want to continue sports (golf, tennis, hiking) that may become impossible after joint replacement
• Surgery-averse patients: Those who cannot or prefer not to undergo general anesthesia and prolonged rehabilitation
• Patients seeking to delay surgery: Even in advanced cases, stem cell therapy can reduce pain and potentially postpone surgical intervention

Why Patients Choose Cell Grand Clinic in Osaka, Japan

Grand Stem Cell — Four Quality Standards (Fresh / Pure / Young / Dose)

Cell Grand Clinic’s Grand Stem Cell protocol guarantees four specific standards on every knee treatment.

1. Fresh — Cultured Exclusively for You, No Batch Pooling. Every batch of cells is expanded from your own fat tissue over a seven-week culture process, with every batch dedicated to one patient only. No pooling across patients. No frozen storage of finished product. The cells are delivered fresh, peaking in biological activity at the time of administration.

2. Pure — ISCT-Standard FACS Verification (CD73/CD90/CD105 near-100%). Surface-marker testing follows the global standard of the International Society for Cell & Gene Therapy. Cells must express CD73, CD90, and CD105 at near-100% positivity, and must be negative for hematopoietic markers (CD45, CD34). Cells that do not meet these defining mesenchymal stem cell criteria are discarded, not delivered.

3. Young — Passage 3 Strict Limit Preserves Regenerative Capacity. Stem cells age with each passage (laboratory division cycle). Grand Stem Cells are strictly limited to Passage 3 or below — a practice biologically validated by Sun et al. 2024, which showed that clinical outcomes correlate with cellular stemness and senescence markers.

4. Dose — Guaranteed 100 Million+ Cells, Approx. 98% Viability. Viability is verified (approximately 98%) immediately before administration, with the dose guaranteed at a minimum of 100 million cells per knee — the threshold confirmed by 2025 Cao meta-analytic dose-response data.

Every patient at Cell Grand Clinic receives a Certificate of Quality documenting that their Grand Stem Cells met all four standards before administration.

Dr. Yuichi Wakabayashi — ABRM, NIH-trained, 3,000+ Cases

Dr. Yuichi Wakabayashi, M.D., Ph.D., is American Board of Regenerative Medicine (ABRM) certified, NIH-trained, and has personally managed more than 3,000 stem cell cases across approximately 20 countries. He personally conducts every step of every patient’s treatment — consultation, fat harvest, supervision of cell culture, intra-articular injection, and 1/3/6-month follow-up. He has authored seven peer-reviewed English-language publications, including a 2026 case report on knee osteoarthritis in Cureus. Cell Grand Clinic is featured in The Wall Street Journal, is a Medical Excellence JAPAN member clinic, and is a 2026 Healthcare Business Review APAC Top Regenerative Medicine Solution in APAC awardee.

15 MHLW-Notified Treatment Plans

Cell Grand Clinic holds one of the broadest portfolios of any regenerative medicine clinic in Japan. Our knee OA treatment is not “experimental” or “off-label.” It is provided under a provision plan notified to Japan’s Ministry of Health, Labour and Welfare and reviewed by a certified special committee for regenerative medicine.

Compare this to the situation in many other countries, where stem cell clinics operate with little regulatory oversight, using uncharacterized cell preparations with no quality control requirements.

Japan’s regulatory framework. Japan regulates cell-based treatment directly under the Act on the Safety of Regenerative Medicine (2014). A clinic providing cultured autologous cell therapy must have its treatment plan reviewed by an MHLW-certified special committee for regenerative medicine, notify the plan to the Ministry of Health, Labour and Welfare, use a licensed cell processing facility subject to inspection, report adverse events, and keep consent and traceability records. Cultured autologous cells such as ADSC for joint disease fall under Type 2 of the Act’s three risk classes. Cell Grand Clinic has 15 MHLW-notified regenerative medicine provision plans; knee osteoarthritis treatment with cultured autologous ADSCs is one of them (plan PB5240089), with documented dose, indication and ongoing safety reporting. Mexico, Panama and the Cayman Islands do not have an equivalent national framework for autologous cell processing, and most overseas clinics there rely on donor stock cells produced for general use.

Practical points for international patients. Consultations are in English directly with the physician; Mandarin interpretation is available; each visit takes about 3 days; there is one in-house consultation fee (JPY 55,000, credited toward treatment). See our guide for American patients and guide for Singapore patients, or request a consultation.

Frequently Asked Questions

Q1: Does stem cell therapy work for knees?

Yes, with limits. The 2025 Cochrane review of 25 randomized trials found that stem cell injections may improve knee osteoarthritis pain (about 1.2 points on a 0–10 scale) and function compared with placebo at up to 6 months, with low-certainty evidence because products and doses varied. Trials restricted to culture-expanded MSCs (Cao 2025, 8 RCTs, 502 patients) show significant 6- and 12-month WOMAC improvement, strongest for high-dose adipose-derived cells.

Q2: How much does stem cell therapy for knees cost?

At Cell Grand Clinic in Osaka, culture-expanded autologous ADSC therapy for knees starts from JPY 2,970,000 (approx. USD 19,800) per session, tax included, for 100 million cells — including blood tests, fat harvest, quality testing (approx. 98% viability) and 1/3/6-month remote follow-up. Same-day injections in the United States are typically USD 5,000–12,000 per knee; culture-expanded protocols USD 15,000–30,000. Travel and the JPY 55,000 online consultation (credited toward treatment) are additional.

Q3: How long do stem cell knee injections last?

Clinical evidence demonstrates sustained improvement at 12 months in the 2025 Cao meta-analysis, with 5-year durability documented for a single high-dose (1×10⁸ cells) autologous ADMSC injection in Kim et al. 2022 (Stem Cells Translational Medicine). Individual results vary based on KL grade, activity level, and overall health. An additional injection is considered at about 12 months if the first is insufficient.

Q4: Is stem cell therapy for knees safe? What are the side effects?

Randomized trials show no significant difference in adverse events versus control (Cao 2025) and no treatment-related adverse events over 5 years after a single high-dose injection (Kim 2022). Common side effects are temporary pain, swelling or bruising at the fat harvest site and in the injected knee. Any joint injection carries a small risk of infection, including septic arthritis. Long-term, population-level safety evidence is still rated very low certainty by the 2025 Cochrane review.

Q5: Stem cell therapy or knee replacement — which is better?

They answer different problems. Total knee replacement is definitive for bone-on-bone (KL grade IV) knees with deformity. Culture-expanded stem cell therapy is for KL grade I–III knees that still have cartilage to protect and where conservative care has failed; it aims to postpone or avoid surgery. Many patients use it to keep working or playing sport while deferring a replacement.

Q6: Is stem cell therapy effective for bone-on-bone (KL Grade IV) knees?

Stem cells cannot rebuild a fully collapsed joint surface. For KL Grade IV patients who cannot undergo TKA or who choose not to, stem cell therapy is the most effective non-surgical pain-and-function intervention available — based on Cao 2025 meta-analytic data — and can provide meaningful pain reduction and improved daily function for 1–2 years. For surgical candidates with severe deformity, TKA is the better long-term choice.

Q7: What is the success rate of stem cell therapy for knees?

There is no single success rate. The 2025 Cao meta-analysis demonstrated statistically significant WOMAC improvement in the pooled MSC group at both 6 and 12 months, with high-dose adipose-derived protocols showing the largest effect sizes. A 2023 Phase III RCT in KL Grade 3 patients (Kim, Lee, Lee et al. 2023) showed VAS reduction of 25.2 versus 15.5 for placebo (P=.004) at 6 months. “Success” rates depend on KL grade, dose, and individual response — but the evidence base for symptomatic improvement at 6 and 12 months is strong. In the 2025 Cochrane pooled analysis, 68% of stem-cell-treated patients reported treatment success versus 53% with placebo (very low-certainty evidence).

Q8: Are amniotic or umbilical cord “stem cell” injections the same thing?

No. Independent laboratory studies found no viable mesenchymal stem cells in commercial amniotic fluid products (Panero et al. 2019) or in a cord blood product (Fortier et al. 2021); the cells present were mostly dead or were leukocytes. These products may contain growth factors, but they are not stem cell therapy. Culture-expanded autologous cells are counted and characterized (ISCT markers, viability) before injection.

Q9: Can knee cartilage grow back?

Knee cartilage has very limited natural ability to regrow because it has no direct blood supply, and no treatment fully regrows a structurally collapsed joint. In early-to-moderate (KL I–III) osteoarthritis, however, mesenchymal stem cell therapy can protect existing cartilage and support limited repair — documented in 18 of 21 clinical studies (Copp et al. 2023). The goal is to preserve and modestly regenerate cartilage thickness, not to grow a new joint surface.

Q10: Where can I get stem cell therapy for knees, and can international patients be treated in Japan?

Stem cell therapy for knees is offered worldwide, but cell type, dose and regulatory oversight vary widely. Cell Grand Clinic in Osaka, Japan treats international patients from about 20 countries under an MHLW-notified provision plan, with consultations in English directly with the physician, two visits of about 3 days each, and remote 1/3/6-month follow-up.

Conclusion: Postpone the Knee Replacement — Repair the Cartilage First

For KL grade I–III knee osteoarthritis that no longer responds to conservative care, culture-expanded autologous adipose-derived stem cell therapy is the non-surgical option with the strongest randomized evidence: significant pain and function improvement at 6 and 12 months in the 2025 Cao meta-analysis, a positive Phase III RCT in KL grade 3 knees, and a safety profile comparable to control injections — with the honest caveat from the 2025 Cochrane review that cartilage regeneration remains unproven at the population level.

Cell Grand Clinic provides this treatment in Osaka, Japan under an MHLW-notified provision plan, with 100 million counted, characterized autologous cells per knee and a published, peer-reviewed case report of its own outcomes.

References

All citations are linked inline in the body of the article. Vancouver-style reference list:

1. Cao M, Ou Z, Sheng R, 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;16(1):122. doi:10.1186/s13287-025-04252-2 (PMID 40055739)
2. Kim KI, Lee MC, Lee JH, et al. Clinical Efficacy and Safety of the Intra-articular Injection of Autologous Adipose-Derived Mesenchymal Stem Cells for Knee Osteoarthritis: A Phase III, Randomized, Double-Blind, Placebo-Controlled Trial. Am J Sports Med. 2023;51(9):2243-2253. doi:10.1177/03635465231179223 (PMID 37345256)
3. Kim KI, Lee WS, Kim JH, et al. Safety and Efficacy of the Intra-articular Injection of Mesenchymal Stem Cells for the Treatment of Osteoarthritic Knee: A 5-Year Follow-up Study. Stem Cells Transl Med. 2022;11(6):586-596. doi:10.1093/stcltm/szac024 (PMID 35567774)
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7. Pers YM, Rackwitz L, Ferreira R, et al. Adipose Mesenchymal Stromal Cell-Based Therapy for Severe Osteoarthritis of the Knee: A Phase I Dose-Escalation Trial. Stem Cells Transl Med. 2016;5(7):847-856. doi:10.5966/sctm.2015-0245 (PMID 27217345)
8. Sun H, Zhai H, Han K, et al. Clinical outcomes of autologous adipose-derived mesenchymal stem cell combined with high tibial osteotomy for knee osteoarthritis are correlated with stem cell stemness and senescence. J Transl Med. 2024;22(1):1039. doi:10.1186/s12967-024-05814-3 (PMID 39558365)
9. Whittle SL, Johnston RV, McDonald S, et al. Stem cell injections for osteoarthritis of the knee. Cochrane Database Syst Rev. 2025;4(4):CD013342. doi:10.1002/14651858.CD013342.pub2 (PMID 40169165)
10. Wakabayashi Y. Symptomatic Improvement Following Intra-articular Injection of Cultured Autologous Adipose-Derived Mesenchymal Stem Cells in Kellgren-Lawrence Grade 3 Knee Osteoarthritis: A Case Report With One-Year Follow-Up. Cureus. 2026;18(8):e113830. doi:10.7759/cureus.113830 (PMID 42688850)
11. Panero AJ, Hirahara AM, Andersen WJ, Rothenberg J, Fierro F. Are Amniotic Fluid Products Stem Cell Therapies? A Study of Amniotic Fluid Preparations for Mesenchymal Stem Cells With Bone Marrow Comparison. Am J Sports Med. 2019;47(5):1230-1235. doi:10.1177/0363546519829034 (PMID 30844295)
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Updated: 2026.09.22