Abstract:Objective To establish a finite element model of the T2-L5 thoracolumbar spine and verify its validity to provide numerical model support for exploring the dynamic response characteristics and injury mechanism under spinal impact loads. Methods A three-dimensional (3D) finite element model of T2-L5 thoracolumbar spine was established based on CT scanning data. The load-rotation angle curve of the T12-L1 segment under different moments (flexion, extension, rotation, and lateral bending conditions) was calculated and compared with the data reported in the literature. Free-fall loads at different heights were applied to the finite element models of the T2-6, T7-11, and T12-L5 spine. The peak axial force and bending moment were obtained by finite element simulation analysis and compared with data reported in the literature. Results The maximum rotation angle of the T12-L1 finite element model was -2.24°-1.55° under moments in different directions, which was in good agreement with the literature data. The peak axial force of T2-6, T7-11, and T12-L5 spine finite element models subjected to different free-fall loads was 1.7-5.3 kN, 1.3-5.5 kN, and 1.3-7.5 kN respectively, which were within the error range reported in the literature. Stress nephograms of the spine and intervertebral discs showed that the vertebral body was first stressed from the outer edge. The intervertebral disc was subjected to the main load by the nucleus pulposus, consistent with the actual spinal injury mechanism. Conclusions The T2-L5 spine model established in this study can correctly simulate the biomechanical behavioral characteristics of the spine under different working conditions, and the analysis results are effective.