A discoloured area under the skin caused by leakage of blood from damaged capillaries (tiny blood vessels). At first, the blood appears blue or black; then the breakdown of haemoglobin turns the bruise yellow. If a bruise does not fade after a week, or if bruises appear for no apparent reason or are severe after only minor injury, they may be indications of a bleeding disorder. (See also black eye; purpura.)
(contusion) n. an area of skin discoloration caused by the escape of blood from ruptured underlying vessels following injury. Initially red or pink, a bruise gradually becomes bluish, and then greenish yellow, as the haemoglobin in the tissues breaks down chemically and is absorbed. It may be necessary to draw off blood from very severe bruises through a needle, to aid healing. A bruise may be the sign of previous assault, detected on clinical examination or at *autopsy. In a child it may be the only (and vital) evidence of *child abuse. See also burn.
Bruises, or contusions, result from injuries to the deeper layers of the skin or underlying tissues, with variable bleeding but without open wounds. Bruises range from a slight bluish discoloration, due to minimal trauma and haemorrhage, to a large black swelling in more severe cases. Diseases such as HAEMOPHILIA and SCURVY, which reduce COAGULATION, should be suspected when extensive bruises are produced by minor injuries. Bruises change colour from blue-black to brown to yellow, gradually fading as the blood pigment is broken down and absorbed. Bruising in the abdomen or in the back in the area of the kidneys should prompt the examining doctor to assess whether there has been any damage to internal tissues or organs. Bruising in children, especially repeated bruising, may be caused by physical abuse (see CHILD ABUSE and NON-ACCIDENTAL INJURY (NAI)). Adults, too, may be subjected to regular physical abuse.... bruises
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