Establishment and validation of finite element model for pelvis artery injury under impacts / 医用生物力学

ABSTRACT

Objective To construct and validate a 3D finite element model of pelvis-femur-soft tissue complex including artery, and investigate the mechanical response of pelvis artery under side impact loads. Methods The 3D finite element model of the pelvis-femur-soft tissue complex was constructed from CT images of one female volunteer, including bone tissues, arteries, enveloping soft tissues, cartilage and ligaments of the pelvic joints (sacroiliac joint, hip joint and pubic symphysis). The whole model utilized linear elastic solid elements to simulate bone tissues. Nonlinear elastic connector elements were employed to represent ligaments. Soft tissues, including the cartilage, enveloping soft tissues and arteries, were modeled as solid elements with hyper-elastic material. Side impact was conducted on the complex with impact mass of 22.1 kg at the impact velocity of 3.13 and 5 m/s, respectively, and the output of the complex model was then recorded. Results Simulation results matched the results of pelvic side impact experiments reported in literature. When the complex model was impacted at the velocity of 3.31 and 5 m/s, respectively, the maximum equivalent stress of arteries was 98 and 216 kPa, and the maximum principle strain was 14.9% and 20%, respectively. The risk of artery injury was relatively low. Conclusions This established pelvis-femur-artery complex model was validated and thus reliable to be used for investigating the dynamical response and injury analysis on pelvis artery under impact loads, and provides some biomechanical foundation for predicting artery injuries.