Abdominal injury analysis of a 6-year-old pedestrian finite element model in lateral impact

Abstract

A previously developed finite element (FE) model of a 6-year-old pedestrian abdomen was used to analyse internal organs injuries in lateral impact tests in conjunction with scaling methods. The model was applied to reconstruct adult abdominal cadaver experiments in lateral impact to verify its biofidelity by comparing simulation results with scaled experimental response corridors. Simulation results showed that the abdominal force-deformation curves were well matched with the scaled experimental corridors in different impact speeds. The maximum values of abdominal impact force, deformation and viscous criterion (VC) were proportional to impact velocity. In terms of compression and viscous criterion, the paediatric abdomen had a 25% probability risk of AIS4+ (Abbreviated Injury Scale) abdominal injury in impact velocities of 6.7 m/s and 9.4 m/s. Judging by the first principal strain, contusion or rupture of the left kidney, stomach and spleen appeared in simulations of 6.7 m/s and 9.4 m/s, while liver rupture appeared only in simulations of 9.4 m/s. Predicted internal organ injuries were found to be consistent among the force, deformation, and VC basis injury criteria. The maximum abdominal impact force was inversely proportional to the impact angle, while the abdominal deformation was proportional to the impact angle. Therefore, the model can be further applied to analyse abdominal injuries for a 6-year-old human in pedestrian impact.