ABSTRACT
Objective To study the mechanics of moderate and severe brain injury of pedestrians in road traffic accident by establishing the virtual model of impact occipital bone injury.Methods The clinical data were used to analyze comlnon mode and characteristics of moderate and severe brain injury of pedestrians.Then,the corresponding finite element model built by using Hypermesh software was used to to analyze the changes of intracranial pressures and compare with injury characteristics by using Ls-Dyna soft-ware. Results The conlmon injury mode of moderate and severe brain injury of pedestrians wag the con-tact impact of occiputal part,characterized by"eontrecoup injury",mainly including subdural hemorrhage,extradural hemorrhage and contusion in the opposite parts to the impact point.The simtdation resuhs showed that when the impact was at right occiputal bone.the peak value of condensing force decreased from the right occipital lobe.to the left frontal lobe,while the peak value of tension increased gradually and reached maximum at the surface of left frontal lobe. Conclusions Moderate and severe brain injury of pedestrian is commonly caused by impacting the occiputal bone in road traffic accident.The tension deformation in frontal or temporal lobes and the distribution of vessels in grey matter may be main biomeehanies leading to "contrecoup injury".
