An abrasion is an injury in which the surface of the skin is rubbed by a rough object, most commonly skin abrasions on the palms, elbows, knees, and lower legs. The abrasion is visible as a break in the epidermis, a pale white color of the wound, and many small bleeding spots and oozing of tissue fluid. Because the dermis is rich in nerve endings, the injury is often very painful, but the regenerative capacity of the epidermal cells is very strong, such as wounds without infection will heal very quickly, and can not leave scars. Abrasions caused by external forces. Including gunshot, gold blade, bruises, bruises, holding weights, fall, or by external impact, weapon injury. Due to the role of blunt (slightly rough) mechanical friction, resulting in epidermal peeling, rolled as the main manifestation of the injury. Can be manifested as scratches, abrasions, impact marks, indentation, pressure and abrasion marks, etc., the damage is slight, but can reflect the point of action of violence, the direction of the role of violence, the intent of violence and the characteristics of the injury caused by the material, etc.. A fine and shallow plow-scar type damage is formed in the sliding direction of the friction surface. What are the common skin abrasions? Head trauma: scalp lacerations are mostly caused by sharp or blunt objects. The size of the fissure, the depth varies, the edge of the wound is neat or not neat, sometimes accompanied by skin contusion or defect, due to the rich blood vessels of the scalp, blood vessel rupture is not easy to close by itself, even if the wound is small bleeding is also serious, and even shock occurs as a result. Laryngeal trauma: the result of a direct blow of violence, such as traffic accidents, workplace accidents, self-strangulation or strangulation injuries, boxing or blunt force injuries. According to the direction of the external force can occur in different degrees of contusion, such as the external force from the side, because the larynx can be moved to the opposite side, the injury is relatively light, often no fracture, only laryngeal mucous membrane damage, cricoarytenoid joint dislocation, and so on. When hit by external force from the front, the injury is often more serious, resulting in longitudinal fracture of the middle of the thyroid cartilage, fracture of the back of the cricoid cartilage and damage to the mucous membrane of the larynx. Ocular trauma: In production, life and sports, masonry, earth, fists, balls, falls, traffic accidents and explosions (e.g., firecrackers) produce shock waves, which are a common cause of blunt contusion of the eye. When a blunt force strikes the eye, it can produce a direct injury at the site of the blow, and because the eye can be viewed as an incompressible sphere, the blunt force can be transmitted within the eye and to the wall of the eye, causing multiple indirect injuries. This is primarily the concept of blunt contusion. Sports Skin Abrasions: During sports, the skin is dry and dehydrated and is also prone to sweating. Skin abrasions occur due to friction when the protective layer of the skin surface comes into contact with clothing. The hot and humid weather and large body size are the causes of skin abrasions. After the abrasion, if the abrasion site is shallow, only need to apply red potion; if the abrasion wound is dirty or there is blood seepage, saline should be used to clear the wound and then apply red potion or purple potion.