腰椎斜扳手法时椎间盘的有限元分析

Finite element analysis of the intervertebral disc during lumbar obligue-pulling manipulation

背景:利用计算机技术和有限元法分析法研究中医传统的脊柱推拿手法,来解释手法的作用机制、适应证和禁忌证,可为临床上常用的腰椎斜扳手法提供了客观的、科学的理论依据。目的:应用有限元法了解进行斜扳手法时腰椎间盘的内在应力及位移分布的特点。方法:使用正常腰椎CT片,以Mimics软件系统逐层重建,建立L4～5三维有限元模型。根据手法原理,将腰椎斜扳手法进行分解,把各项力学参数代入三维有限元模型进行计算分析。即时显示手法作用时腰椎间盘的位移和内在应力的变化。结果与结论:椎间盘的应力远小于后部结构;从椎间盘中心到右侧有一个向后的扭转矢量,使椎间盘产生变形。结果证明腰椎斜扳手法对椎间盘是安全的,并且在椎间盘突出的对侧进行手法操作更为合理;腰椎椎管狭窄的患者不宜使用腰椎斜扳手法。

BACKGROUND： Traditional Chinese manipulation maneuver is researched using computer technology and finite element method, which can explain the action mechanism, indication and contraindication of manipulation and provide objective, scientific theoretical basis for clinical lumbar obligue-pulling manipulation. OBJECTIVE： To study the trait of displacement and intra-stress distribution of intervertebral disc during lumbar obligue-puiling manipulation. METHODS： 3D finite element model of L4-5 segments were constructed based on normal lumbar CT images with Mimics software system. The lumbar obligue-pulling manipulation was decomposed by principium of manipulation. The parameter of mechanics was analyzed with the finite element system. The change of intra-stress distribution and displacement in lumbar intervertebral disc were displayed simultaneous during simulating manipulation. RESULTS AND CONCLUSION： The intra-stress of posterior area was smaller than that of intervertebral disc during the lumbar obligue-pulling manipulation. There was a palinal vector from center of the intervertebral disc to the right, which distorted the intervertebral disc. The lumbar obligue-pulling manipulation is safe to the intervertebral disc, and it is more rational for manipulation in the healthy side. The manipulation is not applicable to lumbar spinal stenosis.