Hypertrophic and Keloid Scars
Hypertrophic and Keloid Scars — raised scars that form when the skin overproduces collagen during wound healing. Hypertrophic scars stay within the boundaries of the original injury, while keloids grow beyond them and can continue expanding over time.
Key points
- Both scar types result from an exaggerated collagen response after skin trauma such as acne, piercings, surgery, or burns.
- Hypertrophic scars often flatten and fade gradually on their own, whereas keloids rarely resolve without treatment.
- Keloids are more common in people with deeper skin tones and can have a genetic or familial tendency.
- Common professional interventions include silicone sheets or gels, corticosteroid injections, laser therapy, and pressure dressings.
Raised scarring, by pattern and by site
| Type | What it looks like | What it responds to |
|---|---|---|
| Hypertrophic scar | Raised and firm, inside the wound outline | Silicone and pressure, clinician-directed |
| Keloid | Spreads into skin the injury never touched | Specialist care; recurrence is common |
| Earlobe keloid | Rounded nodule at a piercing site | Clinic treatment, then a pressure device |
| Jawline and beard area | Firm bumps after shaving or deep lesions | Assessment; reviewing the hair-removal method |
| Chest, shoulder or upper back | Thick raised bands along tension lines | Conservative management; a poor elective site |
| Symptomatic raised scar | Itching, tenderness, tingling or burning | Prompt review; symptoms often precede growth |
Why the collagen response overshoots
As the umbrella entry sets out, scarring begins with dermal inflammation; here fibroblasts keep depositing collagen long after remodelling should have stopped, in thick disorganised bundles. In a hypertrophic scar the excess stays inside the original wound margin, appears within weeks and often softens over one to two years. A keloid invades skin the injury never reached, can begin months later, may enlarge for years, and does not regress.
Sites of predilection are consistent — jawline, chest, shoulders, upper back and earlobes, areas of high skin tension or dense pilosebaceous units. Incidence is higher in richly pigmented skin and clusters in families — constitutional susceptibility, not anything done wrong. Keloids are not caused by unclean wounds.
How clinicians manage this, and why recurrence matters
First-line measures are silicone gel or sheeting worn for many hours daily and, on the earlobe, pressure devices; both need three to six months of consistent use before judging the effect. Beyond that, management is clinic-based: intralesional injections every few weeks, cryotherapy, and vascular or fractional lasers to reduce redness and improve pliability.
Excision alone carries a high rate of recurrence, and a recurrent keloid is often larger than the original, so surgery is normally combined with adjuvant treatment. These scars are managed rather than removed: flatter, softer and less itchy is the realistic aim. For anyone with a known tendency, avoiding elective piercings, tattoos or cosmetic procedures at susceptible sites matters more than anything done afterwards.
Why raised scarring is never a self-treatment
A raised scar should be assessed and managed by a clinician rather than treated at home. Picking, home needling, strong acids, and any attempt to cut, burn or tie off a lesion can provoke further growth and infection: renewed injury is the trigger this tissue responds to. Acne that is leaving raised scars deserves early review: the window in which permanent scarring can still be prevented is finite.
Ask for assessment promptly if a raised lesion enlarges, ulcerates, bleeds, discharges, becomes painful or changes colour — not everything raised is a scar. The same applies to a scar restricting movement across a joint, or interfering with shaving or clothing. A child’s skin belongs with a clinician, and prescription decisions sit with the prescriber.
Frequently asked
What is the difference between a hypertrophic scar and a keloid?
A hypertrophic scar stays confined to the area of the original wound, while a keloid spreads beyond the injury site and often keeps growing.
Can silicone products help flatten raised scars?
Silicone sheets and gels are widely studied and can help soften, flatten, and reduce the redness of raised scars when used consistently over several weeks to months.
Will a raised scar flatten on its own?
Hypertrophic scars frequently settle over one to two years, becoming paler and softer without disappearing. Keloids rarely do, which is why the distinction is best made by someone who can examine the scar.
Do keloids come back after they are removed?
Recurrence after excision alone is common, and the returning scar can be larger than the one removed. Surgery is therefore usually paired with other measures and monitored afterwards.
Should I avoid piercings or tattoos if I have had a keloid?
Anyone who has formed one keloid is more likely to form another after deliberate skin injury, especially at susceptible sites. Discuss planned piercings, tattoos or cosmetic procedures with a clinician beforehand.
Why does a raised scar itch?
Nerve fibres and inflammatory signalling within the scar produce itch, tingling or tenderness, often while it is still active. Scratching feeds the cycle of injury that keeps it growing.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
