Abstract：
OBJECTIVE: To campare biomechanical effects of different postural compression techniques on three-dimensional model of lumbar disc herniation (LDH) by finite element analysis.
METHODS: Lumbar CT image of a 48-year-old female patient with LDH (heighted 163 cm, weighted 53 kg) was collected. Mimics 20.0, Geomagic Studio, Solidwords and other software were used to establish three-dimensional finite element model of LDH on L4,5 segments. Compression techniques under horizontal position, 30° forward bending and 10° backward extension were simulated respectively. After applying the pressure, the effects of compression techniques under different positions on stress, strain and displacement of various tissues of intervertebral disc and nerve root were observed.
RESULTS: L4, 5 segment finite element model was successfully established, and the model was validated. When compression manipulation was performed on the horizontal position, 30° flexion and 10° extension, the annular stress were 0.732, 5.929, 1.286 MPa, the nucleus pulposus stress were 0.190, 1.527, 0.295 MPa, and the annular strain were 0.097, 0.922 and 0.424, the strain sizes of nucleus pulposus were 0.153, 1.222 and 0.282, respectively. The overall displacement distance of intervertebral disc on Y direction were -3.707, -18.990, -4.171 mm, and displacement distance of nerve root on Y direction were +7.836, +5.341, +3.859 mm, respectively. The relative displacement distances of nerve root and intervertebral disc on Y direction were 11.543, 24.331 and 8.030 mm, respectively.
CONCLUSIONS: Compression manipulation could make herniated intervertebral disc produce contraction and retraction trend, by increasing the distance between herniated intervertebral disc and nerve root, to reduce symptoms of nerve compression, to achieve purpose of treatment for patients with LDH, in which the compression manipulation is more effective when the forward flexion is 30°.
METHODS: Lumbar CT image of a 48-year-old female patient with LDH (heighted 163 cm, weighted 53 kg) was collected. Mimics 20.0, Geomagic Studio, Solidwords and other software were used to establish three-dimensional finite element model of LDH on L4,5 segments. Compression techniques under horizontal position, 30° forward bending and 10° backward extension were simulated respectively. After applying the pressure, the effects of compression techniques under different positions on stress, strain and displacement of various tissues of intervertebral disc and nerve root were observed.
RESULTS: L4, 5 segment finite element model was successfully established, and the model was validated. When compression manipulation was performed on the horizontal position, 30° flexion and 10° extension, the annular stress were 0.732, 5.929, 1.286 MPa, the nucleus pulposus stress were 0.190, 1.527, 0.295 MPa, and the annular strain were 0.097, 0.922 and 0.424, the strain sizes of nucleus pulposus were 0.153, 1.222 and 0.282, respectively. The overall displacement distance of intervertebral disc on Y direction were -3.707, -18.990, -4.171 mm, and displacement distance of nerve root on Y direction were +7.836, +5.341, +3.859 mm, respectively. The relative displacement distances of nerve root and intervertebral disc on Y direction were 11.543, 24.331 and 8.030 mm, respectively.
CONCLUSIONS: Compression manipulation could make herniated intervertebral disc produce contraction and retraction trend, by increasing the distance between herniated intervertebral disc and nerve root, to reduce symptoms of nerve compression, to achieve purpose of treatment for patients with LDH, in which the compression manipulation is more effective when the forward flexion is 30°.
摘要：
目的：通过有限元分析研究不同体位压迫技术对腰椎间盘突出症（LDH）三维模型的生物力学影响。
方法：一名48岁女性LDH患者的腰椎CT图像（身高163厘米，称重53公斤)。模仿20.0，Geomagic工作室，利用Solidwords等软件建立LDH在L4,5段上的三维有限元模型。水平位置下的压缩技术，分别模拟了30°向前弯曲和10°向后延伸。施加压力后，不同位置下的压缩技术对应力的影响，观察椎间盘和神经根各种组织的应变和位移。
结果：L4，5段有限元模型成功建立，并对模型进行了验证。当在水平位置上执行压缩操作时，30°屈曲和10°伸展，环面应力分别为0.732,5.929,1.286MPa,髓核应力分别为0.190,1.527,0.295MPa,环应变分别为0.097、0.922和0.424，髓核应变大小分别为0.153、1.222和0.282。椎间盘在Y方向上的整体位移距离分别为-3.707、-18.990、-4.171mm,Y向神经根位移距离分别为+7.836,+5.341,+3.859mm,分别。Y向神经根与椎间盘的相对位移距离分别为11.543、24.331和8.030mm,分别。
结论：压迫手法可使突出的椎间盘产生收缩和回缩趋势，通过增加椎间盘突出和神经根之间的距离，为了减轻神经压迫的症状，达到LDH患者治疗的目的,其中当前屈为30°时，压缩操作更有效。
方法：一名48岁女性LDH患者的腰椎CT图像（身高163厘米，称重53公斤)。模仿20.0，Geomagic工作室，利用Solidwords等软件建立LDH在L4,5段上的三维有限元模型。水平位置下的压缩技术，分别模拟了30°向前弯曲和10°向后延伸。施加压力后，不同位置下的压缩技术对应力的影响，观察椎间盘和神经根各种组织的应变和位移。
结果：L4，5段有限元模型成功建立，并对模型进行了验证。当在水平位置上执行压缩操作时，30°屈曲和10°伸展，环面应力分别为0.732,5.929,1.286MPa,髓核应力分别为0.190,1.527,0.295MPa,环应变分别为0.097、0.922和0.424，髓核应变大小分别为0.153、1.222和0.282。椎间盘在Y方向上的整体位移距离分别为-3.707、-18.990、-4.171mm,Y向神经根位移距离分别为+7.836,+5.341,+3.859mm,分别。Y向神经根与椎间盘的相对位移距离分别为11.543、24.331和8.030mm,分别。
结论：压迫手法可使突出的椎间盘产生收缩和回缩趋势，通过增加椎间盘突出和神经根之间的距离，为了减轻神经压迫的症状，达到LDH患者治疗的目的,其中当前屈为30°时，压缩操作更有效。
