Abstract: Objective To develop a novel three dimensional finite element（FE） model of the human pelvis and investigate the biomechanics of the pelvic injury and explore the applications of FE approach in forensic medicine. Methods The FE model of pelvis including bilateral iliac bones, sacrum, bilateral femurs, joint cartilages and ligaments was developed with Mimics 13.1 based on the CT images. The CT value of material properties were assigned. A static pressure of 600 N was applied at the upper surface of the sacrum endplate downwards along the vertical axis of sacral bone to validate the model. To simulate the side impacts, the lateral forces of 1, 2, 3, 4 and 5 kN were applied to the trochanter surface of right femur, respectively. The von Mises stress contours, displacement contours and stress distribution curves were subsequently calculated. Results An integrated FE model of pelvis including the joint cartilages and ligaments was successfully established. The model geometry coincided well with the CT images. The stress distributions of pelvis in erect position mainly located near the sacroiliac joints and the greater sciatic notches. Stress concentration was found on the superior and inferior pubis ramus, hip and sacroiliac joints on both sides under side impacts. Conclusion The established FE model has accurate and reliable biomechanical features. The FE model can be used to simulate injury and provide intuitive and accurate evidence for medicolegal expertise.

Key words: forensic pathology, finite element analysis, pelvis, biomechanics