Development and Validation of an Age-Specific Lower Extremity Finite Element Model for Simulating Pedestrian Accidents.

Jing Huang,Yongcheng Long,Yu Yan,Lin Hu

doi:10.1155/2018/5906987

Abstract

The objective of the present study is to develop an age-specific lower extremity finite element model for pedestrian accident simulation. Finite element (FE) models have been used as a versatile tool to simulate and understand the pedestrian injury mechanisms and assess injury risk during crashes. However, current computational models only represent certain ages in the population, the age spectrum of the pedestrian victims is very large, and the geometry of anatomical structures and material property of the lower extremities changes with age for adults, which could affect the injury tolerance, especially in at-risk populations such as the elderly. The effects of age on the material mechanical property of bone and soft tissues of the lower extremities as well as the geometry of the long bone were studied. Then an existing 50th percentile male pedestrian lower extremity model was rebuilt to depict lower extremity morphology for 30- to 70-year-old (YO) individuals. A series of PMHS tests were simulated to validate the biofidelity and stability of the created age-specific models and evaluate the lower extremity response. The development of age-specific lower extremity models will lead to an improved understanding of the pedestrian lower extremity injury mechanisms and injury risk prediction for the whole population in vehicle-pedestrian collision accidents.

Highlights

Pedestrians are road users vulnerable to traffic accidents, who suffer high injury rate and mortality rate
In literature [10], the data in the American Pedestrian Injury Causation Study (PCDS) database was analyzed statistically; the results showed that the injury risk to the lower extremities of the elderly was 2.44 times higher than that of the young people, and the elderly would suffer more serious injuries and require longer treatment cycles
The geometry of the long bone cross-section naturally changed with aging, and the change is associated with marrow cavity area changes

Summary

Introduction

Pedestrians are road users vulnerable to traffic accidents, who suffer high injury rate and mortality rate. The lower extremities and head are the main injury body regions for pedestrians in a vehicle-pedestrian collision accident, accounting for 31.2% and 32.4%, respectively [2]. Many researchers established lower extremity models to study its injury mechanisms in pedestrian collision accidents. Zhang et al [3, 4] improved and verified the material model of the long bone and ligament of the lower extremity based on the THUMS model. Untaroiu et al [5], using a human body extremity model, combined with an accident reconstruction method, simulated pedestrian lower extremity fractures in collision. Wang et al [6] used the multibody system and finite element model to study the long bone fracture of the lower limb based on two cases of real pedestrian accidents. Meng et al [7] established a 6-YO child’s lower extremity long bone model and validated this model with a dynamic

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Conclusion