[Finite element analysis on stress change of lumbar spine].
OBJECTIVE
To build a 3D finite element model of whole lumbar spine and verify its efficiency and analyze the biomechanical change of L3-4 motion segment.


METHODS
L1-L5 segment data were obtained from computed tomography (CT) scans of the lumbar spine of a 40-year-old man with no abnormal findings. A three-dimensional finite element model of the human whole lumbar spine was built in the Mimics and the ABAQUS software. The model was composed of bony vertebrae, articulating facets, intervertebral disc and associated ligaments. The basic stress analysis of L3-4 motion segment was made under the considerations of different material properties of bone, ligaments and facet joints contacting frictional property. The stress on annulus fiber, nucleus pulposus, endplate and facet joints under axial pressure (0.3 MPa, 0.5 MPa, 1.0 MPa, 2.0 MPa & 4.0 MPa) were analyzed.


RESULTS
A three-dimensional finite element model of human L3-L4 motion segment has 272, 619 elements, the stresses were higher in the posterior of annulus fiber, the Max pressure stress (S33) distributed in nucleus pulposus and the center of endplate. The stresses increased as axial pressure rose.


CONCLUSIONS
3D finite element model of whole lumbar spine and L3-4 motion segment were established successfully and the stress analyses were feasible and reliable.
Yan
Jia-zhi
JZ
Department of Orthopeadics, Peking Union Medical College Hospital, Beijing 100730, China.
Wu
Zhi-hong
ZH
Wang
Xue-song
XS
Xing
Ze-jun
ZJ
Song
Hai-feng
HF
Zhao
Yu
Y
Zhang
Jian-guo
JG
Wang
Yi-peng
YP
Qiu
Gui-xing
GX
D000328:Adult; D001696:Biomechanical Phenomena; D020342:Finite Element Analysis; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology*; D008297:Male; D008953:Models, Anatomic; D011859:Radiography