A hypertrophic scar is a raised, firm, often red or itchy scar that stays within the edges of the original wound. It usually appears within a few weeks of an injury or operation and, unlike a keloid, tends to improve gradually over one to two years. Silicone, pressure, massage and steroid injections can speed up that improvement, and surgical revision may help once the scar has matured.
What makes a scar hypertrophic?
During normal healing, collagen production rises and then falls as the wound closes. In a hypertrophic scar, the skin keeps producing collagen for longer than it should, and the fibres are laid down in thick, disorganised bundles. The result is a ridge of firm tissue that sits above the surrounding skin. The scar is often red or purple because of the extra blood vessels involved in this overactive healing.
Common causes and risk factors
- Tension: wounds across joints, the shoulders, chest or anywhere the skin is stretched with movement.
- Delayed healing: infection, wound breakdown or healing that takes longer than about three weeks.
- Burns: especially deeper burns that heal slowly.
- Age and skin type: younger people and those with darker skin tones are more prone.
- Wound closure: wounds closed under tension or left to heal openly.
Hypertrophic scar or keloid?
The key difference is behaviour. A hypertrophic scar stays within the original wound boundaries and tends to settle; a keloid grows outwards onto normal skin, often long after the injury, and rarely regresses on its own. Hypertrophic scars also respond better to treatment and are less likely to return after revision. Sometimes only time will tell, which is why an experienced clinical assessment is useful. Read more in our guide to types of scars.
First-line treatments
Most hypertrophic scars are treated without surgery first:
- Silicone gel or sheets: applied daily for several months once the wound is closed; they hydrate the scar and help it flatten.
- Pressure: garments or dressings that apply steady pressure, used particularly after burns.
- Massage: firm massage with a plain moisturiser for a few minutes several times a day to soften the tissue.
- Sun protection: high-factor sunscreen or clothing to stop the scar darkening.
Consistency matters more than any particular product. Improvement is gradual, over months rather than weeks.
Steroid injections
Where a scar remains thick and itchy despite these measures, steroid injections into the scar can soften and flatten it. They are given every few weeks, and several sessions may be needed. Possible side effects include thinning of the skin, small visible blood vessels and lightening of the skin colour around the scar, so the dose is carefully judged.
When surgery is considered
Surgical scar revision is usually reserved for scars that have not improved after around a year, or where the scar is badly placed or pulling on nearby structures. The scar is removed and the wound re-closed with techniques that take tension off the skin, such as layered closure or a Z-plasty to change its direction. Silicone and, if needed, steroid injections are often continued afterwards to lower the chance of the scar thickening again. See the scar revision page for details.
Reducing the risk after future surgery
If you have had a hypertrophic scar before, tell any surgeon planning an operation, because it changes how the wound is managed. Incisions can often be placed along natural skin creases, closed in layers to reduce tension, and supported with tape for several weeks. Starting silicone as soon as the wound has closed, avoiding stretching the area during the early months, keeping the scar out of the sun and not smoking all help. Early review means that a scar starting to thicken can be treated promptly rather than after it has become established.
When to see a doctor
A raised scar is not dangerous, but see your GP if it is growing beyond the wound, is very painful, bleeds or ulcerates, or restricts movement. If a surgical wound becomes hot, red and swollen, or you develop a fever, contact your surgical team the same day, as infection increases the chance of a thick scar.
Frequently Asked Questions
Do hypertrophic scars go away?
They often flatten and fade over one to two years, although they may not disappear completely. Treatment can speed up improvement.
How long should silicone be used?
Usually for at least two to three months, and often longer, applied daily once the skin has fully healed.
Are hypertrophic scars itchy?
Yes, itching is common while the scar is active. It usually eases as the scar matures.
Can a hypertrophic scar come back after surgery?
It can, which is why surgery is timed carefully and combined with silicone or injections afterwards.
What does treatment cost?
Surgical scar revision is from £950 and other scar treatments are quoted at consultation. The consultation fee of £150 is separate.
