title: [Establishment and validation of normal human L1-L5 lumbar three-dimensional finite element model].
abstract: OBJECTIVE
  To create and validate a L1-L5 lumbar three-dimensional finite element model.
  
  
  METHODS
  The L1-L5 lumbar spines of a male healthy volunteer were scanned with computed tomography (CT). And a L1-L5 lumbar three-dimensional finite element model was created with the aid of software packages of Mimics, Geomagic and Ansys. Then border conditions were set, unit type was determined, finite element mesh was divided and a model was established for loading and calculating. Average model stiffness under the conditions of flexion, extension, lateral bending and axial rotation was calculated and compared with the outcomes of former articles for validation.
  
  
  RESULTS
  A normal human L1-L5 lumbar three-dimensional finite element model was established to include 459 340 elements and 661 938 nodes. After constraining the inferior endplate of L5 vertebral body, 500 kg × m × s⁻² compressive loading was imposed averagely on the superior endplate of L1 vertebral body. Then 10 kg × m² × s⁻² moment simulating flexion, extension, lateral bending and axial rotation were imposed on the superior endplate of L1 vertebral body. Eventually the average stiffness of all directions was calculated and it was similar to the outcomes of former articles.
  
  
  CONCLUSIONS
  The L1-L5 lumbar three-dimensional finite element model is validated so that it may used with biomechanical simulation and analysis of normal or surgical models.
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Zhenqi
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Chenjun
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Jiefu
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Kaifeng
authors.initials: K
authors.lastname: Wang
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Zhixin
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China.
authors.forename: Weida
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Spianl Surgery, Peking University People's Hospital, Beijing 100044, China. Email: Liu_haiying@263.net.
authors.forename: Haiying
authors.initials: H
authors.lastname: Liu
mesh_terms: D020342:Finite Element Analysis; D006801:Humans; D008159:Lumbar Vertebrae; D008297:Male; D008953:Models, Anatomic; D012399:Rotation