Webinar Series

Correlation of Injury Patterns in Pedestrian Fatalities with Motor Vehicle Collision Dynamics and Pedestrian Kinematics

July 7, 2020   |   Categories: Webinar Series

Last Updated on July 7, 2020

Presenter

Dr. Moheem Halari, Department of Pathology and Laboratory Medicine, University of Western Ontario.  I am a medical graduate with a passion for research in forensic medicine. This led me to a master’s degree in Forensic Medical Sciences at Queen Mary University of London. I then pursued a Diploma in Forensic Human Identification offered by the Faculty of Forensic and Legal Medicine at the Royal College of Physicians of London. I was invited by the International Committee of the Red Cross in Geneva to attend the Management of the Dead in Armed Conflicts and Catastrophes course. My teaching experience in Pathology and Neuroscience to medical students, made me aware of the contributions to motor vehicle collision (MVC)–related injury research by Dr. Michael Shkrum, a forensic pathologist, at Western University in London, Ontario and the Director of the Motor Vehicle Safety (MOVES) Research Team funded by Transport Canada. I now conduct PhD research under his supervision.

Title of Abstract

Correlation of Injury Patterns in Pedestrian Fatalities with Motor Vehicle Collision Dynamics and Pedestrian Kinematics

Background

The United Nations reports that annually 1.25 million fatalities due to motor vehicle collisions (MVCs) occur worldwide. Half of these deaths involve vulnerable road users. In 2018, the International Road Traffic Data and Analysis Group reported that in Canada, there was an increase of 21.1% and 7.3% in pedestrian and cyclist fatalities, respectively from 2015 to 2016.

This study’s main objective will be to correlate MVC scene and vehicle findings with injury patterns in pedestrian fatalities investigated by the Office of the Chief Coroner for Ontario (OCCO) and use this analysis to predict MVC dynamics and pedestrian kinematics.

Aims

Aim 1: Determine injury patterns in pedestrian fatalities using the OCCO database.
Aim 2: Determine whether these adult and pediatric pedestrian injury patterns are similar to “classical triads” described in the medical literature.
Aim 3: Determine whether fatal pedestrian injuries caused by vehicles with advanced/anti-lock braking systems (ABS) are different from vehicles without ABS.

Methods

The initial focus was a systematic medical literature review to determine the evidence-base for MVC-pedestrian “triads” (aim 2). This was used to create an Injury Data Collection Form (IDCF). OCCO data was extracted from cases examined at the Provincial Forensic Pathology Unit (PFPU) from 2013 to 2018. During this 6-year period, there was a yearly average of 40 to 50 pedestrian/cyclist deaths. The CT and MRI in the Unit provide more detailed injury information supplementing the pathologists’ observations.

Results

Of 1540 publications, 216 articles met the inclusion criteria and were reviewed. The IDCF was used to collect data from 331 cases. Data collection was done concurrently with a researcher who obtained MVC information for Transport Canada.

Discussion

In 1965, Farley described “The Fatal Triad” of skull-pelvic-extremity fractures. In 1971, a “predictable” pattern comprising knee (distal femur-knee joint-proximal tibia), hip/pelvis and craniocerebral injuries was identified by Waddell and Drucker (“Waddell’s triad”). Although they described this triad in ten adults, publications that followed applied this eponym to injured pediatric pedestrians. Other studies have identified other injury patterns. Our initial data suggests that in at least one-third of the articles for each age group, the following injury patterns emerged:
Children (0 – 14 yr.) – Head/Face/Neck, Thorax, Abdomen/Retroperitoneum, Lower Extremity
Youth (15 – 24 yr.) – Head/Face/Neck, Thorax, Lower Extremity
Adults (25 – 64 yr.) – Head/Face/Neck, Thorax, Abdomen/Retroperitoneum, Lower Extremity, Spine
Elderly (≥ 65 yr.) – Head/Face/Neck, Thorax, Pelvis, Lower Extremity
Despite the frequency of non-fatal and fatal cases in the settings of clinical trauma management and medicolegal death investigation, there is little medical literature on the specific injury patterns for pedestrians that can be used to predict the types of vehicles and collisions involved. Future directions of our study involve a literature review and description of injury patterns involving cyclists.

Conclusions

Various patterns of injury have emerged in literature, but their correlation to the type and speed of vehicle, pedestrian kinematics and collision dynamics is lacking particularly related to the modern vehicle fleet including vans and sports utility vehicles (SUVs). The literature review suggests that injury patterns among the pediatric age group appear to be variations of adult patterns.