On this page
Wound healing is one of the few areas in this field with randomised evidence, controlled trials and measurable endpoints — and almost all of it is about wounds that will not close, rather than about scars people dislike the look of. Stem cell therapy for scars and wound repair covers both, and the evidence sits almost entirely on one side.
The wound healing evidence
A systematic review has covered cells in wound healing — The Efficacy of Stem Cells in Wound Healing: A Systematic Review.
A double-blind randomised phase II trial tested a placental cell-embedded hydrogel for radiation-induced skin damage — Topical application of a placental mesenchymal stem cell-embedded biomaterial hydrogel accelerates the repair of radiation-induced skin damage: a double-blind randomized phase II clinical trial.
A randomised controlled trial compared cell-conditioned medium against a standard dressing in chronic plantar ulcers — The efficacy of topical adipose mesenchymal stem cell-conditioned medium versus framycetin gauze dressing in chronic plantar ulcer of leprosy: A randomized controlled trial.
Double-blind, randomised, against an active comparator, with wound closure as the endpoint. That is a proper design and it is why this page is not graded lower.
Why wounds are easy to study honestly
A wound is either closed or it is not, and the area can be measured from a photograph with a scale in it.
That removes almost every source of bias that plagues the rest of this field. There is no questionnaire, no pain score, no impression of improvement — just a measurement anyone can repeat.
It is also why the wound literature can be believed in a way that aesthetic claims cannot.
Diabetic foot ulcer covers the most-studied application, including a randomised controlled trial.
The diabetic foot work
Cord-derived cell injection has a randomised controlled study in diabetic foot ulcers — Prospective, Randomized, and Controlled Study of a Human Umbilical Cord Mesenchymal Stem Cell Injection for Treating Diabetic Foot Ulcers.
A dermal cell product has been developed specifically for non-healing ulcers — Translational development of ABCB5(+) dermal mesenchymal stem cells for therapeutic induction of angiogenesis in non-healing diabetic foot ulcers.
These target wounds that have failed to heal with standard care, which is the appropriate population for an experimental treatment.
That is a different proposition from treating a healthy person’s scar, which is where most commercial interest sits.
Cosmetic scar improvement is a different question
A scar that has healed is stable tissue. It is less elastic than normal skin, differently pigmented, and lacks hair follicles and sweat glands.
Established treatments — silicone, pressure, steroid injection for raised scars, fractional laser, surgical revision — have their own evidence and their own limits.
Cells added to those treatments are under study. Cells as a standalone treatment for an existing scar have very little behind them.
Nothing returns a scar to normal skin. Improvement in texture, colour and pliability is what is realistically on offer, from any treatment.
Keloid and hypertrophic scars
These are overgrown scars, and they are a specific problem rather than a cosmetic preference. Keloids extend beyond the original wound and recur readily after excision.
They are more common in darker skin, and treatment carries a real risk of making things worse — excision alone frequently produces a larger keloid than the original.
Established management combines steroid injection, pressure, silicone and sometimes radiotherapy after excision, and requires someone experienced in it.
Adding cells is not established here, and the recurrence risk means this is not a good place to experiment.
Why chronic wounds fail to heal
Almost always for an identifiable reason: poor arterial supply, venous congestion, pressure, infection, uncontrolled diabetes, poor nutrition, or continued smoking.
Fixing the reason is what heals the wound. Compression for venous ulcers and offloading for diabetic foot ulcers do more than any biological product.
A treatment applied without addressing the cause will fail, and any improvement will not last.
Peripheral vascular disease covers the arterial side, which must be assessed before anything is applied to a wound.
Nutrition deserves a mention of its own. Healing requires protein, and patients with chronic wounds are frequently depleted. Correcting that is cheap, unglamorous and more likely to help than anything applied topically.
Risks
Infection introduced into a wound, which in a compromised limb can be serious.
Harvest site problems where autologous tissue is used.
Worsened appearance in cosmetic treatment, including pigment change, which is more likely in darker skin types.
Documented adverse events covers what has been reported.
How scars mature
A new scar is red, raised and firm, and it changes for a long time. Most flatten and fade substantially over twelve to eighteen months without any treatment at all.
That timeline matters commercially. A scar treated at three months will look better at fifteen months, and it would have done so anyway.
It also matters clinically: intervening surgically on an immature scar produces worse results than waiting, which is why plastic surgeons generally decline to revise a scar in its first year.
Anyone offering treatment for a recent scar should be asked what the expected natural course is, and why intervening now is better than waiting.
Questions worth asking
- Is this a non-healing wound or a healed scar? The evidence differs enormously.
- Has the reason my wound is not healing been identified and addressed?
- Is this an addition to established scar treatment, or a replacement for it?
- Do I have a keloid tendency, and has that been considered?
Burn recovery covers burn scarring specifically.
Frequently asked questions
Is there good evidence here?
For non-healing wounds, yes — randomised controlled trials with wound closure as the endpoint, which is about as clean a measurement as this field offers.
Can a scar be removed?
No. Improvement in texture, colour and pliability is what any treatment realistically offers, and nothing returns a scar to normal skin.
Why is wound research more believable?
Because a wound is either closed or it is not, and the area can be measured from a photograph. That removes most sources of bias.
What about keloids?
They recur readily and excision alone often produces a larger one. Established management is specific and this is not a good place to experiment.
My ulcer will not heal. What matters most?
Finding out why. Arterial supply, venous congestion, pressure, infection, diabetes control and smoking are the usual reasons, and fixing them heals wounds.
Does this work on old scars?
Cells as a standalone treatment for an existing scar have very little evidence. The trials test them as additions to laser or surgical treatment.
Requesting a medical evaluation
Nothing on this page establishes whether any treatment is appropriate for you. That needs your history, your imaging and your current medications read by a clinician. If you would like that review, send your records and we will tell you honestly whether there is anything worth discussing — including when the answer is no.
This page is general information, not medical advice, and does not create a doctor–patient relationship. Regenerative treatments discussed here are in most cases investigational. Discuss any treatment with a clinician who knows your history.