Because of a highly complex three-dimensional geometry of the pelvis, a variety of load transmission inside the pelvis exists. Due to the variation in pelvis internal load transmission, some of the previous studies revealed a variety of pelvis fracture patterns to pedestrians.

In order to predict pelvis fractures accurately, human finite element (FE) models have been developed in past studies. However, the biofidelity of these pelvis models has not been evaluated sufficiently in terms of pelvis internal load transmission due to the lack of biomechanical data from the literature. In order to address different load paths within the pelvis when subjected to lateral impact load, a recent experimental study investigated the reaction forces at the anterior (i.e., pubic rami) and posterior (i.e., sacrum) sides separately in acetabulum and iliac impacts.

The aim of this study was to improve the biofidelity of a pelvis model by performing additional validations against the published experimental data. The pelvis model used in this study was based on the FE pelvis model developed in a previous study. The structure and geometry of the baseline pelvis model were further improved. The geometry of the pubic symphysis was newly created by using CT images, and the articular cartilage was added at the acetabulum and SI joint to better represent overall compliance of the pelvis. The overall width of the pelvis was scaled in order to accurately represent the anthropometry of a mid-sized male.

In addition to the response validations performed in the previous study, the pelvis model was subjected to further validations to confirm enhanced biofidelity. Four force-deflection response corridors from the combinations of the impact locations (acetabulum or iliac crest) and reaction forces (anterior or posterior) were developed in the current study from the published experimental data for dynamic lateral compression of isolated human pelves. Material parameters of the cortical and trabecular bones were modified to better match the response corridors. The results of the response comparisons showed that the modified pelvis model is capable of representing different load paths within a human pelvis in various loading configurations.