Keloids are scars that result from excess collagen in your skin that are present when healing after an injury and are lumpy or ridged in appearance. Hypertrophic scars are similar, but while keloids can spread beyond the borders of the injury, hypertrophic scars stay contained to the site of the trauma. Atrophic scars are scars that are characterized by their sunken or pitted appearance, resulting in a loss of tissue.
Causes
Keloids and hypertrophic scars result from excessive collagen production due to abnormal wound healing. Key causes include genetic predisposition, skin tension at the injury site, and complications like wound infection or inflammation. They often occur after surgery, trauma, burns, or piercings. Atrophic acne scars result from tissue loss that generally occurs after severe acne lesions heal, leaving defined scar tissue and indentations on the skin.
