Electronic Thesis and Dissertation Repository

Thesis Format

Integrated Article


Doctor of Philosophy


Pathology and Laboratory Medicine


Shkrum, Michael J.


Deaths from motor vehicle collisions (MVCs) are a major global health concern, with over 1.35 million fatalities reported annually by the United Nations. More than half involve pedestrians, cyclists, and motorcyclists. Post-mortem examinations by pathologists determine the cause of death and mechanisms of injury and play a significant role in the investigation of the deaths of vulnerable road users.

The purpose of this study was to understand the injury patterns sustained by pedestrians and cyclists fatally injured in motor vehicle impacts.

This study reviews the development of injury patterns described in the medical literature and identifies their limitations in the context of the current motor vehicle fleet, which includes various types of vehicles such as vans, sports utility, and pickup trucks.

The main objectives of this research were to determine injury patterns in pedestrians and cyclists killed in MVCs and compare them with the historical or “classical triads”. The study also aimed to investigate factors related to pedestrian and cyclist kinematics, MVC dynamics, and vehicle type, maneuver, and speed on injury patterns. Multivariate logistic regression models were developed to identify variables that were associated with specific serious to maximal injuries.

Data from 766 post-mortems done between 2013 and 2019 in Ontario were collected. There were 670 pedestrian fatalities and 96 cyclist fatalities. Distinct injury patterns emerged based on age groups, kinematics, vehicle type, vehicle maneuver, and speed. The findings highlighted variations in injury patterns between children, youth, adults, and the elderly, emphasizing the importance of considering age-specific factors when studying trauma.

Based on the multivariate logistic regression models, recommendations have been made to assist pathologists, coroners, and police collision reconstructionists in their analysis of fatal pedestrian and cyclist-MVCs.

Overall, this research contributes to a better understanding of the specific fatal injury patterns sustained by pedestrians and cyclists involved in MVCs. By considering collision dynamics, vehicle type, and other relevant factors, this study provides valuable insights for assisting MVC reconstruction and investigation, and postmortem assessment supporting future motor vehicle research and regulation in mitigating and preventing serious injuries.

Summary for Lay Audience

Motor vehicle collisions (MVCs) cause a staggering 1.35 million deaths annually worldwide. More than half involve pedestrians, cyclists, and motorcyclists.

Investigations into pedestrian and cyclist fatalities from MVCs include autopsies done by pathologists to document injuries and determine a cause of death.

This study aims to analyze the injuries seen in fatally injured pedestrians and cyclists and link them to the MVCs that caused them.

The research reviews and discusses the relevance of the medical literature on MVC pedestrian and cyclist injuries, particularly in relation to the current motor vehicle fleet, which includes various vehicle types like vans, sports utility, and pickup trucks.

The study collected data from 766 postmortem examinations (670 pedestrians; 96 cyclists) done in Ontario between 2013 and 2019. By determining distinct injury patterns that could cause death and their relation to the victim’s age, MV type, collision characteristics, and pedestrian post-collision trajectories, this study can assist in police MVC reconstruction, postmortem examination, and analysis, as well as coroners’ investigations. This knowledge is especially important for evaluating newer vehicles equipped with features promoted as protective of pedestrians and cyclists, such as automatic emergency braking systems.

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

Included in

Pathology Commons