Department of Orthopedics, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China.
Department of Orthopedics, Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710004, China.
Sci Rep. 2021 Jan 29;11(1):2632. doi: 10.1038/s41598-021-82086-7.
The aim of the study was to evaluate the biomechanical properties of a novel nonfused artificial vertebral body in treating lumbar diseases and to compare with those of the fusion artificial vertebral body. An intact finite element model of the L1-L5 lumbar spine was constructed and validated. Then, the finite element models of the fusion group and nonfusion group were constructed by replacing the L3 vertebral body and adjacent intervertebral discs with prostheses. For all finite element models, an axial preload of 500 N and another 10 N m imposed on the superior surface of L1. The range of motion and stress peaks in the adjacent discs, endplates, and facet joints were compared among the three groups. The ranges of motion of the L1-2 and L4-5 discs in flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation were greater in the fusion group than those in the intact group and nonfusion group. The fusion group induced the greatest stress peaks in the adjacent discs and adjacent facet joints compared to the intact group and nonfusion group. The nonfused artificial vertebral body could better retain mobility of the surgical site after implantation (3.6°-8.7°), avoid increased mobility and stress of the adjacent discs and facet joints.
本研究旨在评估新型非融合人工椎体治疗腰椎疾病的生物力学性能，并与融合人工椎体进行比较。构建并验证了完整的 L1-L5 腰椎有限元模型。然后，通过用假体替换 L3 椎体及其相邻椎间盘来构建融合组和非融合组的有限元模型。对于所有有限元模型，在 L1 的上表面施加 500N 的轴向预加载和另外 10N·m 的扭矩。比较三组中相邻椎间盘、终板和小关节的活动范围和应力峰值。在屈伸、左右侧屈、左右旋转运动中，融合组 L1-2 和 L4-5 椎间盘的活动范围大于完整组和非融合组。与完整组和非融合组相比，融合组在相邻椎间盘和相邻小关节处引起的应力峰值最大。与融合人工椎体相比，非融合人工椎体在植入后能更好地保留手术部位的活动度（3.6°-8.7°），避免相邻椎间盘和小关节活动度增加和应力增加。
