A Study of the Association Between Blunt Thoracic Aortic Injury and a Type of Collision in Fatal Motorcycle Accident

Abstract

Introduction/Objective: To determine the association between blunt thoracic aortic injury (BTAI) and the type of collision in fatal motorcycle riders in Thai postmortem cases.

Methods: Data from autopsy reports of motorcycle riders who were sent for medico-legal autopsies at the Department of Forensic Medicine, Siriraj Hospital, Mahidol University between 1^st January 2018 and 31^st December 2020 and presented with BTAI were retrospectively reviewed. Sex, age, height and weight, causes of death, types of collision, details of aortic injuries and associated injuries were recorded. Descriptive statistics, Mann-Whitney U test and contingency table Chi-square test were analyzed where it was suitable.

Results: There were 180 cases recruited in this study and 173 cases (96.11%) were male. The majority of the collision was frontal collision (152, 84.4%). The most common BTAI site was the aortic isthmus (48.3%) followed by ascending aorta (32.8%). The proportion of ascending aortic injury in the frontal collision was significantly higher than that of a non-frontal collision (P = .011). The average sites of ascending aortic injury and aortic isthmus injury were approximately 1 cm above the sino-tubular junction and 1 cm distal to the left
subclavian artery, respectively. Injuries to ascending aorta and isthmus were significantly associated with sternal fracture and cardiac laceration (P < .01). Aortic isthmus injury was also associated with pelvic fracture (P = .03). Descending aortic injury was associated with
thoracic spine fracture (P < .01).

Conclusions: Injuries to the isthmus were the most common BTAI in motorcycle riders followed by ascending aorta. Sternal fracture and cardiac laceration were associated with injuries to the isthmus and ascending aorta