A hypertrophic scar is a scar that is thicker than usual. During the normal healing process of a wound scar tissue forms and typically over months the scar becomes flat and white. Hypertrophic scars have excessive amounts of collagen which causes their raised appearance. Hypertrophic scars tend to occur in areas where there is tension on the wound.
A keloid appears as a smooth, firm, rubbery growth in an area of injury. Keloids tend to be much larger than the original wound and can be uncomfortable or itchy. Why certain individuals are prone to making keloids is unclear, however keloids are see fifteen times more frequently in African Americans.
The main difference between a hypertrophic scar and a keloid is that a keloid extends beyond the borders of the original wound while a hypertrophic scar does not.
There are multiple treatment options to improve hypertrophic scars and keloids, however keloids are more challenging to treat. These options include creams, silicone gel or patches, surgical excision, intralesional corticosteroid injections, pulsed dye laser, skin needling and subcision. With any type of scarring the most important measure to help wound healing is to avoid the sun.