Blunt force trauma to skull with various instruments.

Deaths due to blunt force trauma to the head as a result of assault are some of the most common cases encountered by the practicing forensic pathologist. Previous studies have shown inflicting injury to the head region is one of the most effective methods of murder. The important factors that determine severity of trauma include the type of weapon used, type and site of skull fracture, intracranial haemorrhage and severity of brain injury. The aim of this study was to determine the characteristics of blunt force trauma to the skull produced by different instruments. Nine adult monkeys (Macaca fascicularis) skulls were used as models. Commonly found blunt objects comprising of Warrington hammer, hockey stick and open face helmet were used in this study. A machine calibrated force generator was used to hold the blunt object in place and to hit the skulls at forces of 12.5N and 25N. Resultant traumatic effects and fractures (linear, depressed, basilar, comminuted, and distastic) were analyzed according to type of blunt object used; surface area of contact and absolute force (N/cm(2)) delivered. Results showed that all investigated instruments were capable of producing similar injuries. The severity of trauma was not related to the surface area of contact with the blunt objects. However, only high absolute forces produced comminuted fractures. These findings were observational, as the samples were too small for statistical conclusions.