目的:评估三种腰椎椎间融合技术对全身振动下骨质疏松脊柱并发症发生的影响。
方法:对先前开发和验证的L1-S1的非线性有限元模型进行了修改,以开发ALIF,PLIF和TLIF骨质疏松模型。在每个模型中,骶骨的下表面是绝对固定的,通过腰椎轴施加400N的从动件载荷,并在L1的上表面上施加±40N(5Hz)的轴向正弦垂直载荷,以进行瞬态动力学分析。椎间盘内压的最大值,横环物质上的剪切应力,圆盘凸起,关节面应力,以及螺杆和杆的应力,以及它们的动态响应曲线,被收集。
结果:在这三个模型中,TLIF模型产生了最大的螺杆和杆应力,PLIF模型产生了最大的笼-骨界面应力。在L3-L4级别,与其他两种型号相比,椎间盘内压力的最大值和动态响应曲线,在ALIF模型中,环形地面物质和椎间盘隆起的剪切应力均较低。然而,ALIF模型中相邻段的小面接触应力高于其他两个模型。
结论:在全身振动下的骨质疏松脊柱中,TLIF具有最高的螺钉和杆断裂风险,PLIF网箱下沉的风险最高,ALIF上邻近椎间盘退变的风险最低,但相邻小关节退化的风险最高。
To evaluate the effects of 3 lumbar interbody fusion techniques on the occurrence of complications in an osteoporotic spine under whole-body vibration.
A previously developed and validated nonlinear finite element model of L1-S1was modified to develop anterior lumbar interbody fusion (ALIF), posterior lumbar interbody fusion (PLIF), and transforaminal lumbar interbody fusion (TLIF) models with osteoporosis. In each model, the lower surface of the sacrum was absolutely fixed, a follower load of 400N was applied through the axis of the lumbar spine, and an axial sinusoidal vertical load of ±40N (5 Hz) was imposed on the superior surface of L1, to perform a transient dynamic analysis. The maximal values of intradiscal pressure, shear stress on annulus substance, disc bulge, facet joint stress, and screw and rod stress, along with their dynamic response curves, were collected.
Among these 3 models, the TLIF model generated the greatest screw and rod stress, and the PLIF model generated the greatest cage-bone interface stress. At the L3-L4 level, compared with the other 2 models, the maximal values and dynamic response curves of intradiscal pressure, shear stress of annulus ground substance, and disc bulge were all lower in the ALIF model. However, the facet contact stress at the adjacent segment in the ALIF model was higher than that in the other 2 models.
In an osteoporotic spine under whole-body vibration, TLIF has the highest risk of screw and rod breakage, PLIF has the highest risk of cage subsidence, and ALIF has the lowest risk of upper adjacent disc degeneration, but the highest risk of adjacent facet joint degeneration.