What is the Difference Between Keloid and Hypertrophic Scar?

Keloid and hypertrophic scars are both types of scars that form due to excess collagen production during wound healing. They differ in several aspects, including size, growth, and treatment:

1. Size: Hypertrophic scars are contained within the area of the initial wound, while keloids extend beyond the initial wound borders.
2. Growth: Keloids continue to grow beyond the original wound margin, whereas hypertrophic scars reach a certain size and may stabilize or regress over time.
3. Collagen Pattern: On histological examination, hypertrophic scars have collagen in a wavy, regular pattern, while keloids have no distinct pattern of collagen.
4. Color: Hypertrophic scars may have a lighter pink or red color, while keloids can be darker, with a purple-red hue.
5. Etiology: Both keloids and hypertrophic scars result from excessive scar formation after skin injury. However, keloids can also occur spontaneously without any significant preceding skin injury.
6. Prevalence: Hypertrophic scarring is common and can occur in all races and ages, while keloids are less common and more likely to develop in individuals with darker skin tones.

Treatment for both types of scars may involve similar methods, but incomplete treatment can cause keloids to grow over time. It is essential to distinguish between keloids and hypertrophic scars when considering intensive treatment options.

Comparative Table: Keloid vs Hypertrophic Scar

Here is a table comparing the differences between keloid and hypertrophic scars:

Both hypertrophic scars and keloids form due to excess collagen during wound healing, but they have distinct differences. Hypertrophic scars stay within the confines of the wound, while keloids can grow beyond the wound site. Hypertrophic scars are more common and can occur in all races and ages, whereas keloid scars are less common and are more frequent in those with Fitzpatrick skin types.