Identification and differential diagnosis of perimortem blunt force trauma in tubular long bones.

The identification of perimortem injuries from human remains is crucial in the forensic evaluation of skeletal trauma. The purpose of this article is to review the criteria currently used by forensic experts for the identification and differential diagnosis of perimortem blunt force trauma in long bones. The mechanism of injury and the associated fracture pattern in long bones is discussed because it is fundamental in the forensic interpretation. The distinction between postmortem and perimortem fractures is based on the evidence of an osteogenic reaction. The first signs of healing can be detected macroscopically, radiographically, or histologically. Perimortem injuries may be distinguished from postmortem damage by examining certain attributes such as fracture angle and fracture margins. Additionally, the most commonly encountered taphonomic factors leading to postmorterm damage are described in order to alert the workers of the existence of such pitfalls that may perplex the forensic interpretation of skeletal trauma. Although the distinction of bone damage that occurred long after death from perimortem trauma is relatively easy, the differentiation of fractures inflicted shortly before death or soon after death may be difficult or even impossible.