Abstract: Custom-made pelvic prostheses are normally employed to reconstruct the biomechanics of the pelvis for improving patient’s life quality. However, due to the large demand of biomechanical performance around the pelvic system, the customized prosthesis needs to be studied for its strength and stability. A hemi-pelvic finite element model, including a custom-made prosthesis and the surrounded main ligaments, was created to study the strength and stability of the system. Based on the developed finite element model, the relationship between the pre-stress of the screws and the biomechanical performance of the reconstructed pelvis was investigated. Results indicate that the pre-stress should not exceed 1000 N during surgery in order to prevent fatigue fractures from happening to screws. Moreover, four screws were removed from the pelvic system without affecting the fixing stability of the system, which provide surgical guidance for surgeons in terms of safety and fixation.

Key words: customized hemi-pelvic prosthesis, finite element analysis, biomechanics, screws pre-stress