A static analysis of a three-dimensional finite element model of the Lumbar-Pelvic is conducted to verify the model\'s effectiveness. Adjusting the sacroiliac ligament\'s elasticity modulus under a 10Nm lumbar flexion/extension moment, it simulates ligament tension/laxity to calculate vertebrae displacements, intervertebral disc stress and deformation, nucleus pulposus pressure, facet joint force, and ligament stress.
With the elastic modulus of the sacroiliac ligament changing by +50%, -50%, and -90%, the angular displacement of vertebra 3 in forward flexion changes by +1.64%, -4.84%, and -42.3%, and the line displacements change by +5.7%, -16.4%, and -144.9%, respectively; and the angular displacements in backward extension change by +0.2%, -0.6%, -5.9% and the line displacements change by +5.5%, -14.3%, and -125.8%. However, the angular displacement and center distance between adjacent vertebrae do not change, leading to no change in the maximum stress of the intervertebral disc and the maximum pressure in the nucleus pulposus. Flexion and extension directly affect the deformation and stress magnitude and distribution in the lumbar spine.
While sacroiliac interosseous ligament laxity and tension have little effect on disc deformation and stress, and nucleus pulposus pressure, they reduce the stability of the lumbar-sacral vertebrae. In a forward flexion state, the lumbar ligaments bear a large load and are prone to laxity, thereby increasing the risk of lumbar injury.
方法:对腰椎-骨盆的三维有限元模型进行静态分析,以验证模型的有效性。在10Nm的腰椎屈伸力矩下调整骶髂韧带的弹性模量,它模拟韧带张力/松弛来计算椎骨位移,椎间盘应力和变形,髓核压力,面关节力,和韧带应力。
结果:随着骶髂韧带的弹性模量变化+50%,-50%,-90%,前屈椎骨3的角位移变化+1.64%,-4.84%,和-42.3%,线位移变化+5.7%,-16.4%,和-144.9%,分别;向后延伸的角位移变化+0.2%,-0.6%,-5.9%,线位移变化+5.5%,-14.3%,和-125.8%。然而,相邻椎骨之间的角位移和中心距离不变,导致椎间盘的最大应力和髓核中的最大压力没有变化。弯曲和伸展直接影响腰椎的变形和应力的大小和分布。
结论:虽然骶髂关节间韧带松弛和张力对椎间盘变形和应力影响不大,和髓核压力,它们会降低腰椎的稳定性。在前屈状态下,腰椎韧带承受很大的负荷,容易松弛,从而增加了腰椎损伤的风险。