Does Regenerative Medicine Actually Work?

Sometimes, for some goals, and less reliably than its reputation suggests. For knee osteoarthritis, the most-studied use, pooled trials show platelet-rich plasma (PRP) easing pain more than placebo injections (Bensa et al., 2025), yet a large, carefully blinded trial found PRP no better than saline at 12 months (Bennell et al., 2021), and three kinds of cell injections did no better than a corticosteroid shot at one year (Mautner et al., 2023). In September 2026 the American College of Rheumatology strongly recommended against both PRP and stem cell injections for knee and hip osteoarthritis (American College of Rheumatology [ACR], 2026).

What This Means

“Regenerative medicine” is a label, not a single product. It covers PRP, made from your own blood; bone marrow aspirate concentrate and fat-derived cells, taken from your own body; and donor products such as umbilical cord tissue cells and exosomes. These differ in source, FDA status and research base. Evidence for one does not carry over to another.

“Working” also needs a definition. Most trials measure pain and function scores over 3 to 12 months. Few show a change in the joint itself. In the RESTORE trial, PRP did not change cartilage volume compared with saline (Bennell et al., 2021). In the MILES trial, none of the four injection groups changed their MRI scores from baseline at one year (Mautner et al., 2023). In this field, “it works” usually means pain improved more than in a comparison group, not that tissue grew back.

Placebo matters too. Knee injection trials show strong placebo responses; the MILES authors note that response rates in the published research may exceed 50% and last up to six months (Mautner et al., 2023). That is why uncontrolled before-and-after reports are weak evidence.

Candidacy

The best-studied group is adults with knee osteoarthritis (wear-related arthritis of the knee) of mild to moderate severity on X-ray. RESTORE enrolled people 50 and older with Kellgren–Lawrence grade 2 or 3 disease, a standard X-ray scale of arthritis severity (Bennell et al., 2021). MILES enrolled adults 40 to 70 with grade 2 to 4 disease (Mautner et al., 2023). Results from these groups do not automatically apply to the back, the shoulder or other tendons.

Someone is generally a reasonable candidate for a discussion when the pain source is clear, the foundational steps below have been tried, and they understand the product’s FDA status, the self-pay cost and the mixed evidence. Active infection, certain cancers, pregnancy, some blood or platelet disorders and uncontrolled medical conditions are common reasons to pause. So is an expectation of new cartilage. A licensed physician decides candidacy after an evaluation.

Clinical Evaluation

At PrimeCell Regenerative, the evaluation comes before any product decision. I take a history, examine the joint and the nerves around it, review prior imaging, and use ultrasound when it adds information. Knee pain can come from osteoarthritis, a meniscus tear, patellar tendinopathy (irritation of the tendon just below the kneecap) or the hip. I want to know which structure is generating the pain before recommending anything, and a regenerative option only comes up once mainstream care has been considered.

Available Options

For knee and hip osteoarthritis, the 2026 ACR update strongly recommends exercise, weight loss for people with overweight or obesity, topical or oral anti-inflammatory medicines (NSAIDs), and corticosteroid injections into the joint. It conditionally recommends options such as knee bracing, tai chi, acupuncture, duloxetine, radiofrequency ablation of knee nerves, and GLP-1 medications alongside diet and exercise for knee arthritis with obesity. It conditionally recommends against hyaluronic acid injections and dextrose prolotherapy (ACR, 2026). Joint replacement remains an option for advanced disease.

After those, PRP is prepared with FDA-cleared devices and used off-label. Cell-based products and exosomes are investigational. FDA has stated that no regenerative medicine product is approved for orthopedic conditions such as osteoarthritis, back pain or tendonitis (U.S. Food and Drug Administration [FDA], 2021). Florida law allows physicians to offer stem cell therapy that is not FDA-approved for orthopedics, wound care and pain management, with accredited sourcing, a published notice and signed consent (Fla. Stat. § 458.3245, 2025). PrimeCell offers PRP and, for selected patients with written consent, investigational cell-based and exosome options.

Benefits, Limitations and Risks

Possible benefits. Some patients report less pain and better function, and pooled PRP trials support a real average effect over placebo in knee osteoarthritis (Bensa et al., 2025). In MILES, there were no procedure-related serious adverse events among 440 patients who received injections (Mautner et al., 2023).

Limitations. PRP preparations vary widely, and higher platelet concentrations appear to perform better (Bensa et al., 2025). Many protocols need more than one session. These procedures are self-pay. At one year, the cell injections in MILES matched a corticosteroid injection rather than beating it (Mautner et al., 2023).

Risks. In MILES, joint swelling occurred in 24% of patients after umbilical cord tissue cells versus 7% after corticosteroid, bruising occurred in 39% after fat harvest, and roughly a third of patients in the harvest arms reported procedural pain (Mautner et al., 2023). FDA has received reports of blindness, tumor formation and serious infections after unapproved regenerative products (FDA, 2021).

What the Evidence Shows

What it does establish. A 2025 meta-analysis of 18 randomized trials with 1,995 patients found PRP beat placebo on pain and function in knee osteoarthritis, with pain gains large enough to be clinically meaningful at 3 and 6 months (Bensa et al., 2025). Autologous cell procedures showed a good short-term safety record in a large multicenter trial (Mautner et al., 2023). In April 2026 the American Academy of Physical Medicine and Rehabilitation published practice guidance on patient selection, dosing, technique and informed consent for PRP in knee osteoarthritis (American Academy of Physical Medicine and Rehabilitation [AAPM&R], 2026).

What it does not establish. In RESTORE, 288 patients received PRP or saline, and the groups did not differ in symptoms or cartilage at 12 months (Bennell et al., 2021). In MILES, no cell product outperformed corticosteroid, and none changed MRI scores (Mautner et al., 2023). The 2026 ACR update strongly recommends against PRP, rating the evidence low certainty, and against stem cell injections, rating it moderate certainty, for knee and hip osteoarthritis (ACR, 2026). No trial shows cartilage regrowth, and no regenerative product is FDA-approved for an orthopedic condition (FDA, 2021). Specialty groups read the same data differently, which is itself a sign the question is unsettled.

Recovery and Next Steps

After a joint injection, soreness and swelling for a few days are common, and harvest sites can bruise. In MILES, almost all procedure-related effects had settled by the one-week follow-up (Mautner et al., 2023). Results are judged over weeks to months, ideally with the same pain and function score recorded before and after.

Before any decision, bring prior imaging, a list of past injections and therapy, and your current medications. Ask what product would be used, its FDA status, and what result would count as success.

Orlando Considerations

PrimeCell is a self-pay practice. Regenerative procedures are generally not covered by insurance, and any plan is quoted in a written estimate after the evaluation; qualifying patients can use Cherry payment plans. For cell-based options, Florida requires the physician to provide the state notice and obtain a signed consent form covering FDA status, risks and alternatives (Fla. Stat. § 458.3245, 2025).