Wu Weidong, Chen Chun, Ning Jinpei, Sun Peidong, Zhang Jinyuan, Wu Changfu, Bi Zhenyu, Fan Jihong, Lai Xianliang, Ouyang Jun
Department of Anatomy, Guangdong Provincial Medical Biomechanical Key Laboratory, Academy of Orthopedics of Guangdong Province, Southern Medical University, Guangzhou 510515, China;Wuhan Concrete Technology Company Limited, Gaoxin Avenue 818, Wuhan 430200, Hubei, China e-mail:
Department of Orthopedics, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou 325000, Zhejiang, China e-mail:
J Biomech Eng. 2017 Jun 1;139(6). doi: 10.1115/1.4036393.
A finite element model was used to compare the biomechanical properties of a novel anterior transpedicular screw artificial vertebral body system (AVBS) with a conventional anterior screw plate system (ASPS) for fixation in the lower cervical spine. A model of the intact cervical spine (C3-C7) was established. AVBS or ASPS constructs were implanted between C4 and C6. The models were loaded in three-dimensional (3D) motion. The Von Mises stress distribution in the internal fixators was evaluated, as well as the range of motion (ROM) and facet joint force. The models were generated and analyzed by mimics, geomagic studio, and ansys software. The intact model of the lower cervical spine consisted of 286,382 elements. The model was validated against previously reported cadaveric experimental data. In the ASPS model, stress was concentrated at the connection between the screw and plate and the connection between the titanium mesh and adjacent vertebral body. In the AVBS model, stress was evenly distributed. Compared to the intact cervical spine model, the ROM of the whole specimen after fixation with both constructs is decreased by approximately 3 deg. ROM of adjacent segments is increased by approximately 5 deg. Facet joint force of the ASPS and AVBS models was higher than those of the intact cervical spine model, especially in extension and lateral bending. AVBS fixation represents a novel reconstruction approach for the lower cervical spine. AVBS provides better stability and lower risk for internal fixator failure compared with traditional ASPS fixation.
使用有限元模型比较一种新型经椎弓根前路螺钉人工椎体系统（AVBS）与传统前路螺钉钢板系统（ASPS）在下颈椎固定中的生物力学性能。建立了完整颈椎（C3-C7）模型。在C4和C6之间植入AVBS或ASPS结构。对模型进行三维（3D）运动加载。评估内固定器中的冯·米塞斯应力分布以及活动范围（ROM）和小关节力。通过mimics、geomagic studio和ansys软件生成并分析模型。下颈椎完整模型由286,382个单元组成。该模型根据先前报道的尸体实验数据进行了验证。在ASPS模型中，应力集中在螺钉与钢板的连接处以及钛网与相邻椎体的连接处。在AVBS模型中，应力分布均匀。与完整颈椎模型相比，两种结构固定后整个标本的ROM均降低约3°。相邻节段的ROM增加约5°。ASPS和AVBS模型的小关节力高于完整颈椎模型，尤其是在伸展和侧弯时。AVBS固定代表了一种下颈椎的新型重建方法。与传统的ASPS固定相比，AVBS提供了更好的稳定性和更低的内固定器失败风险。
