The brassiere 'sign' - a distinctive marker in crush asphyxia.

The diagnosis of crush asphyxia typically relies on a history of chest or abdominal compression with the finding of skin petechiae and congestion. The following three cases of crush asphyxia demonstrate a distinctive pattern of petechiae and congestion associated with close-fitting clothing: Case 1, a 49-year-old woman who was crushed under a large hay bale; Case 2, a 35-year-old woman who was crushed between a wall and a car; Case 3, a 49-year-old woman who was crushed between a crane and the side of a truck. At autopsy in all three cases there were facial, conjunctival, neck and upper anterior chest petechiae. However, few or no petechiae, and reduced congestion, were observed in areas beneath the victims' brassieres. Deaths in these cases were all due to crush asphyxia, with the pattern of petechiae on the chests of the victims influenced by close-fitting clothing that had compressed cutaneous vasculature. This brassiere 'sign' provided a readily observable and easily recordable sign of crush asphyxia due to chest compression, and illustrated that vascular engorgement is necessary for the development of petechiae in these circumstances.