Ballistic long bone fracture pattern: an experimental study.

When dealing with badly preserved cadavers or skeletal human remains, the assessment of death circumstances remains challenging. When forensic evidence cannot be taken from the skin and soft tissue, the information may only be deduced from more resistant elements such as bone. Compared to cranial gunshot injuries, reliable data on ballistic long bone trauma remains scarce. This study aims to define ballistic fracture characteristics in human long bones. The shaft of 16 femurs and 13 humeri from body donors was perpendicularly shot with a 9-mm Luger full metal jacket bullet at an impact velocity of 360 m/s from a distance of 2 m. Some bones were embedded in Clear Ballistics Gel®, and some were shot without soft tissue simulant in order to better visualise the fracture propagation on the high-speed camera. The fractures were examined macroscopically and compared between the sample groups. We consistently found comminuted fractures with a stellate pattern. Fracture details were classified into entrance, exit and general characteristics. For some traits, we detected different occurrence values in the group comparison. The results indicate that some of the traits depend on bone properties such as shaft diameter, bone length and cortical thickness. The presence of ballistic gel also influenced some fracture traits, emphasising the relevance of soft tissue simulant in osseous gunshot experiments. This study revealed new insights in the detailed fracture pattern of human long bones. These may serve as guidelines for the identification and reconstruction of gunshot trauma in human long bones.

Osteonal Damage Patterns from Ballistic and Blunt Force Trauma in Human Long Bones.

Forensic anthropologists play a key role in skeletal trauma analysis and commonly use macroscopic features to distinguish between trauma types. However, this approach can be challenging, particularly in cases of highly comminuted or incompletely recovered fractures. Histological analysis of microscopic fracture characteristics in fractured bones may thus help provide additional information on trauma type and bone fracture biomechanics in general. This study analysed the extent of microcrack damage to osteons in long bones with blunt force trauma (BFT) and gunshot trauma (GST), from both traumatic death cases and post-mortem experimental fractures. We identified four types of osteonal damage (OD). In traumatic death cases, OD affecting the inside of the osteon and compromising the Haversian canal (type 1) was found to be indicative of BFT. Moreover, OD affecting the cement line (type 3) and interstitial lamellae (type 4) was more common in the GST samples. OD affecting the inside of the osteon without compromising the Haversian canal (type 2) was not found to be indicative of either trauma type. In cases of experimental fractures, our study revealed that post-mortem fractures in dry bone samples featured the highest amount of OD, particularly of type 4. This study also found that the experimentally produced GST featured similar OD patterns to GST death cases. These findings support our hypothesis that there are distinct osteonal damage patterns in human long bones with BFT and GST, which are of relevant value for trauma analysis in forensic anthropology.

Out-of-Hospital Tissue Donation: Multidisciplinary Donor Circuit in a Forensic Institute.

OBJECTIVE: We aimed to implement an out-of-hospital system of generating donors that increases donation and answers the growing demand for tissue for therapeutic purposes. MATERIAL: The Catalan Health Service issued the 4/2015 instruction promoting the integration of the donation network through collaboration with the Donor Center of Catalonia (DCC). The creation of DCC facilitated the signing of an agreement between The Blood and Tissue Bank, the Department of Justice of the Generalitat de Catalunya, the Emergency Medical System, and the Hospital Clínic Barcelona for the procurement of tissues in the Institute of Legal Medicine and Forensic Sciences of Catalonia (IMLCFC), where the autopsies of all judicial deaths in the province of Barcelona are performed. METHODS: The Emergency Medical System informed the DCC of those instances that ended with the code "deceased." DCC assessed the possible donor on arrival at the IMLCFC, checked the medical history through the shared clinical record, and obtained family consent by telephone interview. If consent was obtained, then judicial authorization was sought. RESULTS: In 2016, 152 donors of corneas were obtained (9.7% of the annual amount in Catalonia), 149 in 2017 (9.4% of the annual amount), and 133 donations in 2018. At the end of 2017, we started multitissue retrieval and obtained in 2018 a total of 76 donors. CONCLUSIONS: Out-of-hospital tissue donation in a forensic institute is possible. In less than 3 years, IMLCFC has become the third largest eye tissue contributor among the Catalan tissue donation network and the first contributor in musculoskeletal tissues in 2018.