Injury patterns in motor vehicle collision-pediatric pedestrian deaths

Injury patterns in motor vehicle collision-youth pedestrian deaths

OBJECTIVE

The objective of this study was to describe fatal pedestrian injury patterns in youth aged 15 to 24 years old and correlate them with motor vehicle collision (MVC) dynamics and pedestrian kinematics using data from medicolegal death investigations of MVCs occurring in the current Canadian motor vehicle (MV) fleet.

METHODS

Based on a systematic literature review, MVC-pedestrian injuries were collated in an injury data collection form (IDCF). The IDCF was coded using the Abbreviated Injury Scale (AIS) 2015 revision. The AIS of the most frequent severe injury was noted for individual body regions. The Maximum AIS (MAIS) was used to define the most severe injury to the body overall and by body regions (MAISBR). This study focused on serious to maximal injuries (AIS 3-6) that had an increasing likelihood of causing death. The IDCF was used to extract collision and injury data from the Office of the Chief Coroner for Ontario (OCCO) database of postmortem examinations done at the Provincial Forensic Pathology Unit (PFPU) in Toronto, Canada, and other provincial facilities between 2013 and 2019. Injury data were correlated with data about the MVs and MV dynamics and pedestrian kinematics.The study was approved by the Western University Health Science Research Ethics Board (Project ID: 113440; Lawson Health Research Institute Approval No. R-19-066).

RESULTS

There were 88 youth, including 54 (61.4%) males and 34 (38.6%) females. Youth pedestrians comprised 13.1% (88/670) of all autopsied pedestrians. Cars (n = 25/88, 28.4%) were the most frequent type of vehicle in single-vehicle impacts, but collectively vehicles with high hood edges (i.e., greater distance between the ground and hood edge) were in the majority. Forward projection (n = 34/88, 38.6%) was the most frequent type of pedestrian kinematics. Regardless of the type of vehicle, there was a tendency in most cases for the median MAISBR ≥ 3 to involve the head and thorax. A similar trend was seen in most of the pedestrian kinematics involving the various frontal impacts. Of the 88 cases, at least 63 (71.6%) were known to be engaged in risk-taking behaviors (e.g., activity on roadway). At least 12 deaths were nonaccidental (8 suicides and 4 homicides). Some activities may have been impairment related, because 26/63 (41.3%) pedestrians undertaking risk-taking behavior on the roadway were impaired. Toxicological analyses revealed that over half of the cases (47/88, 53.4%) tested positive for a drug that could have affected behavior. Ethanol was the most common. Thirty-one had positive blood results.

CONCLUSION

A fatal dyad of head and thorax trauma was observed for pedestrians struck by cars. For those pedestrians hit by vehicles with high hood edges, which were involved in the majority of cases, a fatal triad of injuries to the head, thorax, and abdomen/retroperitoneum was observed. Most deaths occurred from frontal collisions and at speeds more than 35 km/h.

Comparison of pediatric pelvic fractures and associated injuries caused by different types of road traffic accidents

PURPOSE

To explore the clinical characteristics of pediatric pelvic fracturs caused by traffic accidents and to analyze the accompanying injuries and complications.

METHODS

A total of 222 cases involved traffic accidents was enrolled in this case-control study. The data of children with pelvic fractures caused by traffic accidents who were admitted to our hospital from January 2006 to December 2021 were analyzed retrospectively. Sex, age, Tile classification, abbreviated injury scale score, injury severity score, mortality, and accompanying injuries were studied. The ANOVA was used for measurement data, and the non-parametric rank sum test was used for non-normally distributed data. The Fisher's exact probability method was used for the count data.

RESULTS

Of all enrolled cases, 140 are boys and 82 are girls, including 144 aged < 6 years, 65 aged between 6 and 12 years, and 13 aged > 12 years. Depending on the injury mechanism, there are 15 cases involving pedestrians vs. motorcycles (PVM), 91 cases involving pedestrians vs. passenger cars (PVC), 78 cases involving pedestrians vs. commercial vehicles (PVV), and 38 cases involving motor vehicles vs. motor vehicles (MVM). Associated injuries are reported in 198 cases (89.2%), primarily involving the abdomen injury in 144 cases (64.9%), and lower limb injury in 99 cases (44.6%). PVV injury involves longer hospital stay (p = 0.004). Intensive care unit admission rate is significantly higher in the MVM group than in other groups (p = 0.004). Head injury (p = 0.001) and face injury (p = 0.037) are more common in the MVM group, whereas abdominal injury (p = 0.048) and lower limb injury (p = 0.037) are more common in the PVV group. In the MVM group, the brain injury (p = 0.004) and femoral neck injury (p = 0.044) are more common. In the PVM group, the mediastinum (p = 0.004), ear (p = 0.009), lumbar vertebrae (p = 0.008), and spinal cord (p = 0.011) are the most vulnerable regions, while in the PVV group, the perineum (p < 0.001), urethra (p = 0.001), rectum (p = 0.006), anus (p = 0.004), and lower limb soft tissues (p = 0.024) are the most vulnerable regions. Children aged > 12 years have higher pelvic abbreviated injury scale scores (p = 0.019). There are significant differences in the classification of pelvic fractures among children < 6, 6 - 12, and > 12 years of age, with Tile C being more likely to occur in children > 12 years of age (p = 0.033). Children aged > 12 years are more likely to sustain injuries to the spleen (p = 0.022), kidneys (p = 0.019), pancreas (p < 0.001), lumbar vertebrae (p = 0.013), and sacrum (p = 0.024). The MVM group has the highest complication rate (p = 0.003).

CONCLUSION

PVC is the leading cause of the abdomen and lower extremities injury and has the most concomitant injuries. Different traffic injuries often lead to different associated injuries. Older children are more likely to sustain more severe pelvic fractures and peripelvic organs injuries. The MVM group has the highest extent of injury and complication rates.

Pedestrian injuries in the United States: Shifting injury patterns with the introduction of pedestrian protection into the passenger vehicle fleet

OBJECTIVE

Between 2010 and 2020, an annual average of more than 70,000 pedestrians were injured in U.S. motor vehicle crashes. Pedestrian fatalities increased steadily over that period, outpacing increases in vehicle occupant fatalities. Strategies for reducing pedestrian injuries include pedestrian crash prevention and improved vehicle design for protection of pedestrians in the crashes that cannot be prevented. This study focuses on understanding trends in injuries sustained in U.S. pedestrian crashes to inform continuing efforts to improve pedestrian crash protection in passenger vehicles.

METHODS

More than 160,000 adult pedestrians injured in motor vehicle crashes who were admitted to U.S. trauma centers between 2007 and 2016 were drawn from the National Trauma Data Bank (NTDB) Research Data Sets. The injuries in those cases were used to explore the shifting patterns of pedestrian injuries.

RESULTS

The proportion of pedestrians with thorax injuries increased 3.0 percentage points to 30.7% of trauma center-admitted NTDB pedestrian cases over the 10 years studied, and the proportion with pelvis/hip injuries increased to 21.2%. The proportion of cases with head injuries fell to 48.6%, and the percentage of pedestrians with lower extremity injury (44%) did not change significantly over the 10 year period. Assessment of possible reasons for the shifts suggested that increasing numbers of sport utility vehicles, population increases among the oldest age groups, and improvements in pedestrian protection in U.S. passenger vehicles likely contributed to, but did not completely account for, the relative changes in injury frequency in each body region.

CONCLUSIONS

More important than the reasons for the shifts in the relative frequency of injury to each body region are the conclusions that can be drawn regarding priorities for pedestrian protection research. Though head/face and lower extremity injuries remained the most frequently injured body regions in adult pedestrians admitted to NTDB trauma centers, the relative frequency of thorax and pelvis/hip injuries increased steadily, underlining the increasing importance of pedestrian protection research on these body regions.