Department of Orthopedics, Huashan Hospital, Fudan University, 12 Mid-Wulumuqi Road, Shanghai, 200040, China.
BMC Musculoskelet Disord. 2022 Sep 7;23(1):848. doi: 10.1186/s12891-022-05796-7.
This study aimed to compare the biomechanical differences between anterior cervical discectomy and fusion (ACDF) with multiple-level separate plates and conventional long plates by using finite element analysis.
The following four finite element models were created to simulate various fixations: (1) C4-6 ACDF with multiple plates, (2) C4-6 ACDF with a single plate, (3) C3-6 ACDF with multiple plates, and (4) C3-6 ACDF with a single plate. The maximum Von-mises stress of the cage and fixation, compressive force of the adjacent intervertebral discs and range of motion (ROM) of different segments in the four models were calculated and analyzed.
For C4-6 ACDF, the maximum Von-mises stress of the cage and fixation was lower in the multiple plate fixation model in all motion states. Similarly, for the C3-6 ACDF models, the peak stress of the C3-4 and C5-6 cages was lower with multiple plates fixation in all motions but the stress of the C4-5 cage in the multiple plates model was slightly higher in flexion, bending and rotation. Besides, applying multiple plates in C3-6 ACDF models resulted in a decreased maximum stress of the fixation under different motions except for bending. In both the C4-6 ACDF and C3-6 ACDF models, the ROM values of the adjacent motion segments were lower in the multiple plates models in extension, bending and rotation. In the C4-6 ACDF models, the peak stress on the adjacent intervertebral discs in the multiple plates models was slightly smaller. In C3-6 ACDF models, the maximum stress on the adjacent intervertebral discs was larger in the single-plate model under flexion, bending and rotation movements.
Multiple plates fixation has a positive effect on increasing stiffness and maintaining the ROM of adjacent segments, indicating lower risk of construct failure and adjacent segment degeneration. Further studies are required to confirm its efficacy in clinical practice.
本研究旨在通过有限元分析比较前路颈椎间盘切除融合术（ACDF）中多节段分体板与传统长板的生物力学差异。
建立了以下四个有限元模型来模拟各种固定方式：（1）C4-6 ACDF 多节段分体板固定，（2）C4-6 ACDF 单节段板固定，（3）C3-6 ACDF 多节段分体板固定，（4）C3-6 ACDF 单节段板固定。对四个模型中的 cage 和固定物的最大 Von-mises 应力、相邻椎间盘的压缩力以及不同节段的运动范围（ROM）进行了计算和分析。
在 C4-6 ACDF 中，多节段分体板固定模型在所有运动状态下 cage 和固定物的最大 Von-mises 应力均较低。同样，在 C3-6 ACDF 模型中，多节段分体板固定模型中 C3-4 和 C5-6 cage 的峰值应力在所有运动中均较低，但 C4-5 cage 的应力在多节段模型中的弯曲和旋转时略高。此外，在 C3-6 ACDF 模型中，多节段分体板固定模型在除弯曲外的各种运动中固定物的最大应力均降低。在 C4-6 ACDF 和 C3-6 ACDF 模型中，多节段分体板模型在伸展、弯曲和旋转时相邻运动节段的 ROM 值较低。在 C4-6 ACDF 模型中，多节段分体板模型中相邻椎间盘的峰值应力略小。在 C3-6 ACDF 模型中，在弯曲、弯曲和旋转运动中单板模型中相邻椎间盘的最大应力较大。
多节段分体板固定具有增加刚度和维持相邻节段 ROM 的积极作用，表明构建失败和相邻节段退变的风险较低。需要进一步的研究来证实其在临床实践中的疗效。
