Patterned Abusive Bruises of the Buttocks and the Pinnae

Patterned bruises often result from abusive injuries. The bruise pattern commonly mimics the injuring object.1 With high-velocity injuries, like whippings or slaps, an unbruised negative image of the cord or hand may be outlined by a fine rim of petechae. At the margin of an injuring object, high-velocity impact stretches capillaries sufficiently to tear them. This may occur even when the force does not crush directly impacted vessels. Greater forces rupture directly impacted vessels creating in addition a positive image bruise of the object. If severe forces are applied more slowly, the elastic limit of the capillaries at the margins will not be exceeded.