Abstract:
This dissertation presents the development, validation, and application of a finite element (FE) model of the knee-thigh-hip (KTH) complex of a 50th percentile adult male, incorporating detailed bone, ligament, and muscle geometries and material behaviors. Designed for use in LS-DYNA, the model integrates both passive and active biomechanical elements to simulate realistic human response in frontal automotive crashes. Bone structures were modeled with anisotropic material properties and validated against National Highway Traffic Safety Administration (NHTSA) cadaveric tests for pelvis, femoral head, and femoral condyles. Ligaments were represented with dynamic failure properties, and muscles were modeled as discrete active elements capable of generating movement forces.
The validated KTH model was used to simulate a wide range of frontal impact scenarios, varying thigh flexion, adduction, and abduction angles to examine their influence on lower limb injury mechanisms. Simulations revealed strong dependencies between occupant position and injury patterns, highlighting differences in fracture initiation forces and dislocation risks. The study also evaluated injury thresholds, suggesting adjustments to axial femur force limits for predicting ligament and bone failures. The combination of detailed anatomical accuracy, validated material properties, and parametric positioning makes this model a powerful tool for advancing the understanding of injury biomechanics, improving crash safety standards, and informing the design of protective systems in vehicles.
