Renner Susan M, Natarajan Raghu N, Patwardhan Avinash G, Havey Robert M, Voronov Leonard I, Guo Bev Y, Andersson Gunnar B J, An Howard S
Bioengineering, University of Illinois at Chicago, Chicago, IL, USA.
J Biomech. 2007;40(6):1326-32. doi: 10.1016/j.jbiomech.2006.05.019. Epub 2006 Jul 14.
A 3-D finite element model (FEM) of the lumbar spine (L1-S1) was used to determine the effect of a large compressive follower pre-load on range of motions (ROM) in all three planes. The follower load modeled in the FEM produced minimal vertebral rotations in all the three planes. The model was validated by comparing the disc compression at all levels in the lumbar spine with the corresponding results obtained by compressing 10 cadevaric lumbar spines (L1-S1) using the follower load technique described by Patwardhan et al. [1999. A follower load increases the load-carrying capacity of the lumbar spine in compression. Spine 24(10), 1003-1009]. Further validation of the model was performed by comparing the lateral bending and torsion response without pre-load and the flexion-extension response without pre-load and with an 800 N follower pre-load with those obtained using cadaver lumbar spines. Following validation, the FEM was subjected to bending moments in all three planes with and without compressive follower pre-loads of up to 1200 N. Disc compression values and the flexion-extension range of motion under 800 N follower pre-load predicted by the FEM compared well with in vitro results. The current model showed that compressive follower pre-load decreased total as well as segmental ROM in flexion-extension by up to 18%, lateral bending by up to 42%, and torsion by up to 26%.
使用腰椎（L1-S1）的三维有限元模型（FEM）来确定大的压缩随动预载荷对所有三个平面内运动范围（ROM）的影响。有限元模型中模拟的随动载荷在所有三个平面内产生的椎体旋转极小。通过将腰椎各节段的椎间盘压缩情况与采用Patwardhan等人[1999年。随动载荷增加腰椎在压缩时的承载能力。《脊柱》24(10)，1003 - 1009]所描述的随动载荷技术对10个尸体腰椎（L1-S1）进行压缩所获得的相应结果进行比较，对该模型进行了验证。通过比较无预载荷时的侧弯和扭转响应以及无预载荷和有800 N随动预载荷时的屈伸响应与使用尸体腰椎所获得的结果，对模型进行了进一步验证。验证之后，对有限元模型在有和没有高达1200 N的压缩随动预载荷的情况下施加所有三个平面内的弯矩。有限元模型预测的800 N随动预载荷下的椎间盘压缩值和屈伸运动范围与体外结果吻合良好。当前模型表明，压缩随动预载荷使屈伸运动中的总ROM以及节段ROM最多降低18%，侧弯最多降低42%，扭转最多降低26%。
