非持续载荷下椎间盘的多孔弹性特性

Poroelastic Characteristics of Intervertebral Disc Under Intermittent Load

建立了人体L4/L5段腰椎关节椎间盘多孔弹性有限元模型,并在持续压缩和间歇性压缩载荷作用情况下进行仿真分析,并且将其与相同工况下退化的椎间盘模型进行对比.结果表明,同样状态的椎间盘由于间歇时间的存在,盘的变形和有效应力都相对减小,而孔压值增大.退化的椎间盘由于盘的刚度增加,盘高度和初始孔隙率减小等原因,导致其孔压值和有效应力的变化速度都要比健康的椎间盘快.

A poroelastic finite element model was developed to analyze the biomechanical characteristics of the human spine L4/L5 segment under continuous/intermittent loads, and the results were compared with those of a degenerated model under the same working conditions. The results showed that with the existence of the resting time, the deformation and the effective stress of the intervertebral disc decreased, while the pore pressure increased. Moreover, due to the increased stiffness and the decreased height and initial pore ratio of the degenerated disc, the changing rate of the pore pressure and the effective stress are faster than those of the healthy disc.