Effectiveness Of Modified Low-profile Plate Fixation For Dennis Type ? Sacral Fracture:A Finite Element Analysis

Objective:To compare the stability of sacroiliac screw,traditional locking plate and modified low-profile plate for the treatment of Dennis type ? sacral fracture by three-dimensional(3D)finite element analysis,in order to provide a mechanical basis for the effectiveness of modified low-profile plate fixation.Method:The pelvic images were obtained by CT scan,and the effective 3D finite element models of pelvis and its internal fixation models were established by software.The left Dennis type ? sacral fracture was simulated,followed by fixation with sacroiliac screw,traditional locking plate and modified low-profile plate,respectively.The displacement of the three internal fixation models under vertical load and vertical load+left torsion load was observed.Results:Under vertical load,the maximum displacement of the sacroiliac screw fixation,traditional locking plate fixation and modified low-profile plate fixation for sacral fracture was 0.117,0.187 and 0.137 mm,respectively.Meanwhile,under vertical load+left torsion load,the maximum displacement of the three fixation models was0.137,0.511 and 0.393 mm,respectively.Conclusion:Among the three internal fixation methods,the sacroiliac screw exhibits the best mechanical stability in the treatment of sacral fracture,and the modified low-profile plate fixation is superior to the traditional locking plate.