Cao Fu, Fu Rongchang, Wang Wenyuan
School of Mechanical Engineering, Xinjiang University, Urumqi, China.
PLoS One. 2021 Apr 15;16(4):e0250270. doi: 10.1371/journal.pone.0250270. eCollection 2021.
The quadrilateral anterior cervical plate (ACP) is used extensively in anterior cervical discectomy and fusion (ACDF) to reconstruct the stability of the cervical spine and prevent cage subsidence. However, there have been no comparison studies on the biomechanical performance of quadrilateral ACP and triangular ACP. The objective of this study is to investigate the functional outcomes of quadrilateral ACP and triangular ACP usage in ACDF surgery. In this study, a finite element model of intact C1-C7 segments was established and verified. Additionally, two implant systems were built; one using triangle anterior cervical plates (TACP) and another using quadrilateral orion anterior cervical plate (QACP). Both models were then compared in terms of their postoperative biomechanical performance, under normal and excessive motion. Compared to QACP, the peak stress of the TACP screws and plates occurred at 359.2 MPa and 97.2 MPa respectively and were the highest during over extension exercises. Alternately, compared to TACP, the endplate peak stress and the cage displacement of QACP were the largest at over extension, with values of 7.5 MPa and 1.2 mm, respectively. Finally, the average stress ratio of bone grafts in TACP was relatively high at 31.6%. In terms of biomechanical performance, TACP can share the load more flexibly and reduce the risks of cage subsidence and slippage but the screws have high peak stress value, thereby increasing the risk of screw slippage and fracture. This disadvantage must be considered when designing a TACP based implant for a potential patient.
四边形颈椎前路钢板（ACP）广泛应用于颈椎前路椎间盘切除融合术（ACDF），以重建颈椎稳定性并防止椎间融合器下沉。然而，目前尚无关于四边形ACP和三角形ACP生物力学性能的比较研究。本研究的目的是探讨在ACDF手术中使用四边形ACP和三角形ACP的功能结果。在本研究中，建立并验证了完整C1-C7节段的有限元模型。此外，构建了两种植入系统；一种使用三角形颈椎前路钢板（TACP），另一种使用四边形Orion颈椎前路钢板（QACP）。然后比较两种模型在正常和过度运动情况下的术后生物力学性能。与QACP相比，TACP螺钉和钢板的峰值应力分别出现在359.2 MPa和97.2 MPa，且在过伸运动时最高。相反，与TACP相比，QACP的终板峰值应力和椎间融合器位移在过伸时最大，分别为7.5 MPa和1.2 mm。最后，TACP中骨移植的平均应力比相对较高，为31.6%。在生物力学性能方面，TACP能够更灵活地分担负荷，降低椎间融合器下沉和滑移的风险，但螺钉的峰值应力值较高，从而增加了螺钉滑移和骨折的风险。在为潜在患者设计基于TACP的植入物时，必须考虑这一缺点。
