Hypertrophic scars

A hypertrophic scar stays inside the original wound borders and often flattens on its own over 12 to 18 months. Silicone and pressure are the mainstays while it settles.

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What hypertrophic scars are

In brief

A hypertrophic scar is raised, red and firm, and it stays within the boundary of the original wound. That single feature is what separates it from a keloid, which grows out into skin that was never injured. Both come from excess collagen laid down during healing, but they behave differently and the difference decides the treatment plan. Hypertrophic scars appear at four to eight weeks and often flatten by 12 to 18 months without any treatment. Keloids appear between three and 12 months, about 20% of them after a year, and rarely regress on their own. Treatment for a hypertrophic scar is therefore aimed at speeding up and improving a process that is already going in the right direction.

Also called: Raised scars, thickened scars, immature scars
Tells it apart from a keloid: Stays within the original wound borders
Typical onset: Four to eight weeks after the wound closes
Natural course: Often flattens over 12 to 18 months

When to see a doctor

The scar crosses a joint and is starting to restrict movement. That is a contracture and needs assessment early.
The scar is growing beyond the edges of the original wound, which points to a keloid rather than a hypertrophic scar.
The scar is painful, intensely itchy, or breaking down.
It has been more than 18 months and the scar is still raised and red.

Treatments for hypertrophic scars

Treatment	Evidence	Best for	Cost
Silicone gel or sheets Occlusion and hydration are the proposed mechanism, not pressure. Worn consistently for months rather than weeks. This is the most accessible option and the one with the widest support for raised scars.	Strong	First line while the scar is active	$	Full page →
Steroid injection Triamcinolone flattens and softens raised tissue. Repeated sessions are usual. Skin thinning and pale patches at the injection site are the trade-off.	Strong	Thick, firm scars that are not settling	$$
Pressure therapy Standard care after major burns. Needs to be worn most of the day over months, which is the main reason it fails.	Moderate	Large scars and burn scars, often with silicone	$$
Pulsed dye laser Targets the vessels driving the color. It treats redness more than height, and carries a real risk of pigment change in darker skin.	Moderate	Redness in a scar that is otherwise settling	$$$	Full page →
Scar massage Cheap and low risk. The trial evidence is thinner than the confidence with which it is usually recommended, and is strongest after burns.	Limited	Pliability and comfort alongside other treatment	$	Full page →

What causes them

Tension across the healing wound is the strongest driver, which is why hypertrophic scars are common across the chest, shoulders, and over joints, and why a wound that was slow to close or became infected is more likely to raise. Deeper burns and wounds that took longer than three weeks to heal carry the highest risk. Unlike keloids, family history is not the dominant predictor.

How they change over time

Stage 1

Healing (weeks 0 to 6)

The wound closes and new collagen is laid down. Nothing here yet distinguishes a scar that will raise from one that will not. Protecting the wound and reducing tension is the only lever.

Stage 2

Raised and active (weeks 6 to 26)

The scar is red, firm and above the skin, and it may itch. This is the window where silicone and pressure are usually started, and where treatment has the most to work with.

Stage 3

Remodeling (months 6 to 18)

Redness fades and the scar softens and flattens. Many hypertrophic scars settle substantially in this period without further treatment. A scar still raised and red beyond 18 months is unlikely to resolve on its own.

How this differs across skin tones

Raised scars are more common and tend to be more pronounced in darker skin, and the treatment risks run the same way. Pulsed dye laser and other device work can leave lasting dark or pale patches in Fitzpatrick IV to VI, so conservative settings and a test patch are standard. Silicone and pressure carry no pigment risk, which is part of why they are first line.

What you can do yourself

Worth doing

Start silicone once the wound is fully closed, and keep it on for months rather than weeks. Consistency matters more than the brand.
Protect the scar from the sun. Ultraviolet exposure darkens a healing scar and that pigment can persist.
Reduce tension across the scar where you can, with tape or dressings, particularly over the chest, shoulders and joints.

Not worth doing

Judging the result too early. Many hypertrophic scars are still improving at 12 to 18 months.
Massaging or treating a wound that has not fully closed.
Assuming a raised scar is a keloid. If it stays inside the original wound borders, it is not, and the outlook is better.

Common questions

How do I tell a hypertrophic scar from a keloid?

Look at the borders. A hypertrophic scar stays within the outline of the original wound. A keloid grows past it into skin that was never injured. Timing helps too: hypertrophic scars appear within a couple of months and often flatten, keloids can appear up to a year later and rarely regress.

Will it go away on its own?

Often it will flatten and fade substantially over 12 to 18 months. That is the usual course. Treatment is aimed at improving and speeding up that process, not at rescuing something that would otherwise be permanent.

When should I start treatment?

Once the wound is fully closed. Silicone and pressure are usually started in the first weeks to months, while the scar is still active, because that is when there is most to influence.

Is it the same treatment as for a keloid?

Overlapping, but not the same. Silicone has stronger support for hypertrophic scars, while keloids lean more heavily on injection and carry a much higher recurrence risk after surgery.