Scars fall into a few main types: fine flat scars, raised hypertrophic scars, keloid scars that grow beyond the wound, sunken (atrophic) scars such as acne or chickenpox marks, contracture scars that tighten the skin, and stretch marks. Identifying the type matters, because each behaves differently over time and responds to different treatments.
How scars form
Whenever the deeper layer of skin (the dermis) is damaged, the body repairs it with new collagen. The first weeks involve inflammation and the laying down of new tissue; then, over 12 to 18 months, the scar remodels, becoming paler, flatter and softer. The final appearance depends on your genes, age and skin type, where the wound is on the body, how much tension it is under, and whether healing was delayed by infection or wound breakdown.
The main types at a glance
- Fine line (normotrophic): a flat, pale scar that follows the original wound; the usual outcome of a well-healed surgical incision.
- Hypertrophic: raised, red and sometimes itchy, but confined to the boundary of the wound. Often improves with time.
- Keloid: a firm, rubbery overgrowth that spreads beyond the original wound and rarely regresses on its own.
- Atrophic: sunken scars caused by loss of tissue, such as acne ‘ice pick’ and ‘boxcar’ scars or chickenpox marks.
- Contracture: a scar that tightens and pulls on surrounding skin, most often after burns or across joints, and can restrict movement.
- Stretch marks (striae): linear marks from rapid stretching during growth, pregnancy or weight change; technically a form of scarring within the dermis.
Hypertrophic versus keloid
These two are often confused. A hypertrophic scar develops within weeks of injury, stays within the wound edges and usually flattens over one to two years. A keloid may appear months later, extends onto normal skin, and tends to persist or grow. Keloids are more common on the earlobes, chest, shoulders and upper back, in people with darker skin and in those with a family history. See our detailed guides to hypertrophic scars and keloid scars.
Why some scars look worse than others
Scars across areas of movement or tension, such as the shoulders, chest and joints, are more likely to stretch or thicken. Wounds that became infected, were closed under tension or took a long time to heal tend to leave wider scars. Smoking reduces blood flow to healing skin. Pigmentation also matters: some scars darken (hyperpigmentation), especially with sun exposure, while others become paler than the surrounding skin.
Treatments by scar type
- Raised scars: silicone gel or sheets, pressure, massage and steroid injections; surgical revision once mature.
- Keloids: a combination approach, often steroid injections with or without excision; surgery alone has a high chance of recurrence.
- Sunken scars: dermal filler or fat grafting for some depressed scars; resurfacing treatments offered by dermatology or laser clinics.
- Contractures: surgical release, sometimes with Z-plasty or skin grafts, to restore movement.
- Wide or badly placed scars: excision and careful layered closure, sometimes changing the direction of the scar.
An overview of these approaches is set out in our scar treatment comparison.
When to seek advice
See your GP if a scar is painful, bleeds, breaks down, becomes ulcerated or changes in colour or shape, as new growths within old scars occasionally need assessment. A scar that restricts movement, or a raised scar that is growing, should be reviewed sooner rather than later, because earlier treatment is often more effective.
Specialist assessment
Mr Nassab will examine the scar, ask about how it formed and whether you have had problem scars before, and explain which type it is and what realistic improvement looks like. Scar revision is from £950 with the final quote confirmed after assessment, and the consultation fee of £150 is separate. Cosmetic treatment is for adults aged 18 and over.
Frequently Asked Questions
What is the most common type of scar?
A flat, fine-line scar is the usual result of a cleanly healed wound. Raised and sunken scars are less common but very familiar in clinic.
How long does a scar take to mature?
Typically 12 to 18 months, during which it softens, flattens and fades in colour.
Can any scar be removed completely?
No. Treatment aims to make a scar less noticeable, flatter or more comfortable, but some mark will always remain.
Are stretch marks scars?
Yes, stretch marks are a form of scarring in the deeper skin. They usually fade to silvery lines over time.
Does skin colour affect how a scar heals?
It can. People with darker skin are more prone to keloids and to scars becoming darker, which influences how treatment is planned.
Which scars are hardest to treat?
Keloids are often the most challenging because they can recur after treatment and usually need a combined approach.
