Abstract: ［Abstract］ Objective〖HTSS〗To establish a three-dimensional finite element model of normal lumbar spine, and provide a reliable model for biomechanical research and lumbar spine injury research.
  〖WTHZ〗Methods〖HTSS〗CT and MRI data of lumbar spine of a healthy adult male were collected. The three-dimensional model of lumbar vertebrae and upper sacrum was reconstructed by Mimics software based on CT data. The three-dimensional model of L1-L5 disc nucleus pulposus was reconstructed by MRI data. The biomechanical characteristics of the lumbar spine under flexion, extension, lateral bending and torsion were simulated by applying exercise muscle loads to the model,and verify the validity of the model.
  〖WTHZ〗Results〖HTSS〗A complete three-dimensional finite element model of lumbar spine was established, including the important structures of vertebra, intervertebral disc, upper sacrum, ligament and articular capsule. The total number of nodes was 104 190, and the total number of elements was 339 165. The angular displacement range and the stress distribution characteristics of the intervertebral disc under the condition of exercise were consistent with the biomechanical characteristics of the lumbar spine, which verifies the validity of the model.
  〖WTHZ〗Conclusion〖HTSS〗The three-dimensional finite element model established in this study has a high degree of simulation, and can be used to study the biomechanics of the lumbar spine, to simulate effects of disease and surgery on biomechanics of lumbar spine.

Key words: three-dimensional finite element model, lumbar spine, intervertebral disc