Why some skin injuries grow into permanent, raised scars that defy typical healing

Health · Published 3 October 2026 Swipe more like this →

In short: Keloids are not just stubborn scars; they are an overgrowth of collagen that expands beyond the original injury site. While they are benign and non-contagious, these raised, firm lesions can persist for years, often causing pain or itchiness. Understanding why they form is the first step toward managing them.

A keloid occurs when the body’s wound-healing process goes into overdrive. During typical recovery, collagen acts as a vital protein to mend damaged skin. However, in individuals prone to keloids, the body produces an excess of this protein, resulting in a raised, shiny, and often lumpy scar. Unlike hypertrophic scars, which remain confined to the borders of the initial wound, keloids aggressively grow outward, sometimes reaching sizes as large as a football.

The exact biological trigger remains a mystery, but experts have identified clear risk factors. Keloids are significantly more common in people with brown or Black skin, and they frequently run in families, suggesting a strong genetic component. Age is another critical factor; individuals between 10 and 30 years old are at the highest risk. These scars can emerge from almost any skin trauma—ranging from severe surgical incisions and burns to minor irritations like acne, insect bites, or ear piercings.

Treating keloids is notoriously difficult because they are prone to recurrence. Surgery alone is rarely recommended, as the trauma of the incision can cause the scar to return even larger than before. Instead, clinicians often use a multimodal approach. This may include corticosteroid injections to soften the tissue, cryotherapy to freeze the lesion, or laser therapy. In some cases, providers combine these with pressure garments—which must be worn for up to 20 hours daily—or low-dose radiation to inhibit the fibroblasts responsible for collagen overproduction.

Because keloids are so difficult to eliminate, prevention is paramount for those with a known predisposition. This includes avoiding elective procedures like tattoos or piercings and treating skin conditions like acne early to minimize inflammation. If a keloid does form, seeking professional care quickly is essential, as early intervention offers the best chance to limit the scar's growth and manage associated symptoms like discomfort or restricted joint mobility.

General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.

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