The objective of this study was to develop a computer model and to use it to predict modes of loading that are most likely to produce aortic ruptures. Previously, a three-dimensional (3D) finite element model (FEM) of the human thorax was developed and validated against data obtained from lateral pendulum tests. The model included a detailed description or the heart, lungs, rib cage, sternum, spine, diaphragm, major blood vessels and intercostal muscles. However, the aorta was modeled as a hollow tube using shell elements with no fluid within, and its material properties were assumed to be linear and isotropic. Fluid elements representing blood have been incorporated into the model in order to simulate pressure changes inside the aorta due to impact. The current model was globally validated against experimental data published in the literature for both frontal and lateral pendulum impact tests. Simulations of the validated model for thoracic impacts from a number of directions indicate that the ligamentum arteriosum, subclavian artery, parietal pleura and pressure changes within the aorta are factors that could influence aortic rupture. The model suggests that a right-sided impact to the chest is potentially more hazardous with respect to aortic rupture than any other impact direction simulated in the study. The aortic isthmus was the most likely site of aortic rupture regardless of impact direction. Validation of the kinematics and dynamics of the aorta at the local level could not be done due to a lack of experimental data. For the covering abstract of the conference see ITRD E206605.
Abstract