Summary

Keloid and hypertrophic scars are forms of abnormal wound healing characterised by excessive collagen deposition. Hypertrophic scars are raised, red, and itchy but remain within the boundaries of the original wound and typically regress over time. Keloid scars extend beyond the original wound margins (like "claws"), do not regress spontaneously, and have a very high recurrence rate after excision. Keloids are more common in individuals of Afro-Caribbean descent and typically occur at high-tension sites (earlobes, sternum, shoulders). Treatment includes intralesional steroids (first-line for keloids), silicone sheets, and pressure therapy.

Key Facts

• Hypertrophic: Stays WITHIN wound boundaries; often regresses over 1-2 years
• Keloid: Extends BEYOND wound boundaries ("claws"); does NOT regress
• Risk Factors: Afro-Caribbean skin, high-tension sites (sternum, shoulder, earlobe)
• Treatment (Keloid): Intralesional steroids (Triamcinolone) is gold standard
• Treatment (Hypertrophic): Silicone gel sheets, pressure garments
• Recurrence: Keloid excision has 50-100% recurrence unless combined with adjuvant therapy

Clinical Pearls

"Within = Hypertrophic, Beyond = Keloid": The key distinction is whether the scar stays within the original wound (hypertrophic) or grows beyond it (keloid).

"Keloids Love Ear Lobes": Ear lobes are a classic site for keloids after piercing. Also sternum, shoulders, and upper back.

"Don't Just Excise Keloids": Excision alone has 50-100% recurrence. Always combine with intralesional steroids or radiotherapy.

"Steroids Are First-Line": Intralesional triamcinolone is the gold standard for keloids - flattens the scar by inhibiting collagen synthesis.

Inspection

• Raised, firm scar
• Check if extends beyond original wound edges (keloid)
• Colour (red/pink or hyperpigmented)

Palpation

• Firm, rubbery texture
• Non-tender to mildly tender

Distribution

• High-tension areas (chest, shoulder, ear)
• Check for multiple scars (recurrence, keloid tendency)

Hypertrophic Scars

• Usually regress over 12-24 months
• Good response to silicone and pressure

Keloids

• Do NOT regress spontaneously
• Recurrence rate 50-100% after excision alone
• Better outcomes with combined therapy (excision + steroids/radiotherapy)

Key Guidelines

1. British Association of Dermatologists: Keloid Guidelines
2. International Scar Guidelines

Key Evidence

Intralesional Steroids

• 50-100% response rate for keloids
• Best when combined with other modalities

Silicone

• Meta-analyses support efficacy for prevention and treatment

What Are Keloids and Hypertrophic Scars?

When wounds heal, a scar forms. Sometimes the scar grows more than normal:

• Hypertrophic scar: A raised, red scar that stays within the wound area and usually flattens over time.
• Keloid: A scar that grows beyond the original wound, like spreading fingers. It doesn't go away on its own.

Who Gets Them?

Keloids are much more common in people with darker skin, especially those of African, Asian, or Hispanic heritage. Ear lobes, chest, and shoulders are common sites.

How Are They Treated?

• Steroid injections into the scar are the main treatment for keloids
• Silicone sheets/gel worn over the scar can help
• Surgery may be needed but has high recurrence - usually combined with steroid injections or radiotherapy

Can They Be Prevented?

If you're prone to keloids, avoid unnecessary piercings or surgeries. After any wound or surgery, silicone gel and pressure therapy may help prevent abnormal scarring.