Scars are areas of fibrous tissue (fibrosis) that replace normal skin after injury. A scar results from the biological process of wound repair in the skin and other tissues of the body. Thus, scarring is a natural part of the healing process. With the exception of very minor lesions, every wound (e.g., after accident, disease, or surgery) results in some degree of scarring. An exception to this are animals with complete regeneration, which regrow tissue without scar formation.

Age The older a person is, the slower the skin heals, making scars more likely.
Skin Type In general, people with darker or very light skin are more susceptible to noticeable scarring.
Hormones Different hormonal levels may affect the way a person's skin scars.
Location In places on the body where the skin is subject to tension, such as at the joints or shoulders, more noticeable scars are likely to form.
Complications Infection/inflammation during the healing process means a higher risk of scarring.
Genetic Predisposition Hereditary factors also play a role in the healing of the wound and, therefore, could make the skin prone to scarring.

Some scars have too much collagen and other tissues, which causes raised skin. Some have too little collagen, which causes the scar to be lower than the skin around it. Repaired skin might have no hair follicles, be less elastic (or flexible), and form longer strands of tissue compared to the skin around it. These changes create different types of scars.


Scars can occur from any damage to the skin, but they can be worse if any scabs that form are removed too early. A number of other events or conditions can cause scars.