Hypertrophic vs Keloid: What's the Difference?
Hypertrophic scars are raised, red and firm, but stay within the boundary of the original wound. They typically develop within weeks of injury or surgery and often improve gradually over 1–2 years, even without treatment.
Keloid scars extend beyond the original wound margin, growing into surrounding normal skin. They can continue enlarging for months or years, do not resolve spontaneously, and have a significantly higher rate of recurrence after treatment.
Who Is Affected & Why
Keloid scarring is more common in darker skin types, and there is a clear genetic and familial predisposition. Both keloid and hypertrophic scarring are more likely at sites of higher skin tension — the chest, shoulders, upper back and ear lobes are particularly prone — and after wounds that were infected, closed under tension, or slow to heal. Piercings, acne, chickenpox and minor trauma can all trigger keloid formation in a predisposed individual, sometimes from an injury that seems trivial.
Treatment Ladder
Because keloids in particular tend to recur, treatment is usually staged and combines several approaches rather than relying on any single one.
First-Line, Non-Surgical
- Silicone gel or sheeting — worn over the scar for several months; good evidence for flattening and softening hypertrophic scars
- Pressure therapy — particularly for ear lobe keloids following piercing, using pressure earrings or clips
- Intralesional steroid injections — the mainstay of treatment for both scar types; delivered at 4–6 weekly intervals, reduces bulk, redness and itch
- 5-Fluorouracil (5-FU) injections — often combined with steroid, particularly for keloids resistant to steroid alone
- Laser treatment — vascular laser for redness and itch; can be combined with steroid injection
Surgical Excision — With Adjuvant Treatment
Surgery alone for a keloid carries a high recurrence rate, sometimes higher than the risk of the original scar returning larger than before. For this reason, surgical excision of a keloid is essentially always combined with an adjuvant treatment to suppress recurrence — most commonly a course of steroid injections into the fresh scar, and in some cases adjuvant radiotherapy shortly after excision, which is reserved for keloids at high risk of recurrence or that have failed other treatment. Hypertrophic scars, in contrast, are less prone to recurrence and can often be excised and revised more like a standard problematic scar.
Even with combination treatment, keloids can recur, and no treatment guarantees a flat, imperceptible scar. The realistic goal is a smaller, flatter, less symptomatic scar with a materially reduced — not eliminated — chance of the keloid returning.
Risks & Complications
Recurrence
The principal risk, particularly for keloids excised without adjuvant treatment.
Pigmentation Change
Steroid injection can occasionally cause skin thinning or lightening around the injection site.
Altered Sensation
Temporary numbness or discomfort around the treated scar.
Infection
Uncommon; risk minimised with careful wound care.
Aftercare & Recovery
- Silicone sheeting or gel commenced once the wound has fully healed, continued for 3–6 months
- Steroid injection course typically continues at intervals for several months after surgery
- Sun protection is essential for any scar prone to pigmentation — SPF50+ for 6–12 months
- Regular follow-up to identify early recurrence, when it is easiest to treat