Scarring hyperplasia, also known as scotoma, is caused by excessive proliferation of fibrous connective tissue. The scars bulge the skin surface in a verrucous proliferation with a smooth, red and shiny surface, often found with dilated capillaries. The skin lesions protrude outward from the edges and have a crab foot shape change. The skin lesions vary in size and shape and are hard and cartilage-like in texture. Due to the acute pain sensation, it may be due to sensitive nerve endings or the formation of microneuromas, and the pain can be felt even when lightly touched by clothes. Some scars have shiny, slightly white epidermis and surrounding tissues. Very rarely do they retract on their own, and occasionally they become malignant. Scars are more common on the chest, shoulders, neck, back and ears, and rarely on the eyelids, palms, feet and plantar areas, and external genitalia. In addition to intrinsic factors, they may be associated with weight pulling and respiratory movements of both breasts. Scar tissue can have varying degrees of self-conscious symptoms, which are most evident in hyperplastic scars. These symptoms include itching, tingling or burning pain, irritability or local hypersensitivity, and in some patients, even very pronounced tenderness. Scars near limb joints can interfere with limb movement and lead to joint motion disorders; large scars can cause loss of skin functions such as perspiration. Early localized scars swell and harden with blood, and most do not develop serious functional impairment.