Medicolegal limitations, complications and circumstances of bruising
THE CONTEXT
Bruises have limitations in reconstructing injury mechanisms and may cause serious complications. Irritant-induced skin injuries can also simulate bruising.
Limitations in interpreting bruises
•
Bruise size may not match weapon size, and bruises may appear away from the actual injury site.
•
Bruises may become visible only after several hours or even 1–2 days.
•
Bruises do not indicate the direction of applied force; these limitations make them less valuable than abrasions.
Complications
•
A contusion may contain 20–30 ml of blood or more. Multiple contusions can cause death through shock and internal haemorrhage.
•
Gangrene and tissue death may occur.
•
Pooled blood can support bacterial growth, especially by the clostridial group.
•
Severe sudden compression of subcutaneous tissue may rarely cause pulmonary fat embolism.
Artificial bruises and injury circumstances
•
Applying irritant substances to skin can produce injuries simulating bruises and may be used to make a false charge of assault.
•
Accidental bruises commonly occur over prominences such as the forehead, nose, elbows and knees.
•
Mud, sand, grease or oil may suggest how an injury occurred. Material in open wounds may connect injuries to the crime scene.
•
Alcoholics may develop multiple contusions from minor trauma that can be mistaken for injuries caused by physical violence.
•
Self-inflicted bruises are rare because they are painful.
•
The source associates bruising of the inner thighs and genitalia with rape.