When a wound damages the skin, the type of scarring depends on the extent of the injury. Superficial injury only affects the outermost layer of skin, called the epidermis, and such injury results in minimal scarring. If the injury penetrates deeper than the epidermis, to the underlying dermis, the damage is more severe, and the scarring is more pervasive.
Tissue beneath the epidermis heals by forming collagen fibers. Collagen is a protein produced in the body. Collagen formation is what causes a noticeable scar.
Hypertrophic scars are thick and dark in color. They encompass only the site of the original wound, but can continue to develop and thicken for up to six months. Some people tend to develop hypertrophic scars more readily than others. Hypertrophic scars appear more frequently in young people and people with dark skin, although that does not diminish their appearance in older people, and people of all skin types.
Hypertrophic scars may be difficult for patients not only because of their appearance, but because they feel itchy and uncomfortable. Hypertrophic scars can become thick enough to impinge movement, particularly if they are near a joint.
Reviewed by: Michael Fuller, MD