Zhang Chenchen, Chang Minmin, Zhang Renwen, Tang Shujie
Chenchen Zhang, School of Chinese Medicine, Jinan University, Guangzhou, 510630, China.
Minmin Chang, School of Chinese Medicine, Jinan University, Guangzhou, 510630, China.
Pak J Med Sci. 2021 Mar-Apr;37(2):403-408. doi: 10.12669/pjms.37.2.3223.
To investigate the biomechanical effects of osteoporosis on adjacent segments after posterior lumbar interbody fusion (PLIF).
This study was designed and conducted in the Traumatology and Orthopedics Laboratory, School of Chinese Medicine, Jinan University, Guangzhou, China, between December 2019 and February 2020. A healthy finite element model of L3-S1 was developed along with one PLIF model and one PLIF with osteoporosis model. Based on a hybrid test method, the inferior surface of S1 was entirely fixed, and a preload of 400N combined with an adjusted moment was imposed on the superior surface of L3 in each model to simulate flexion, extension, lateral bending and axial rotation. The intradiscal pressure (IDP), shear stress on annulus fibrosus, and the range of motion (ROM) of L3-L4 and L5-S1 were calculated and compared.
In each direction, the highest value of IDP and shear stress on annulus fibrosus at L3-L4 and L5-S1 was found in the PLIF model, and the lowest value in the healthy model. The largest ROM at L4-L5 appeared in the healthy model, and the smallest value in the PLIF model in each direction. At L3-L4 and L5-S1, the highest ROM in most directions was found in the PLIF model, followed by the PLIF with osteoporosis model, and the lowest value in the healthy model.
Osteoporosis can decrease IDP, shear stress on annulus fibrosus, and ROM at adjacent levels, and slow down the development of ASD after PLIF.
探讨腰椎后路椎间融合术（PLIF）后骨质疏松对相邻节段的生物力学影响。
本研究于2019年12月至2020年2月在中国广州暨南大学中医学院骨伤实验室设计并开展。建立了一个L3-S1的健康有限元模型以及一个PLIF模型和一个骨质疏松PLIF模型。基于混合试验方法，将S1的下表面完全固定，并在每个模型的L3上表面施加400N的预载荷并结合调整后的力矩，以模拟前屈、后伸、侧屈和轴向旋转。计算并比较L3-L4和L5-S1的椎间盘内压力（IDP）、纤维环上的剪应力以及活动范围（ROM）。
在每个方向上，L3-L4和L5-S1处的IDP和纤维环上剪应力的最高值出现在PLIF模型中，而最低值出现在健康模型中。L4-L5处最大的ROM出现在健康模型中，而在每个方向上PLIF模型中的值最小。在L3-L4和L5-S1处，大多数方向上ROM的最高值出现在PLIF模型中，其次是骨质疏松PLIF模型，最低值出现在健康模型中。
骨质疏松可降低相邻节段的IDP、纤维环上的剪应力和ROM，并减缓PLIF术后相邻节段退变（ASD）的发展。
