PDF(Pubmed)
Abstract：
BACKGROUND: Whether polyetheretherketone (PEEK) rods have potential as an alternative to titanium alloy (Ti) rods in transforaminal lumbar interbody fusion (TLIF) remains unclear, especially in cases with insufficient anterior support due to the absence of a cage. The purpose of this study was to investigate biomechanical differences between PEEK rods and Ti rods in TLIF with and without a cage.
METHODS: An intact L1-L5 lumbar finite element model was constructed and validated. Accordingly, four TLIF models were developed: (1) Ti rods with a cage; (2) PEEK rods with a cage; (3) Ti rods without a cage; and (4) PEEK rods without a cage. The biomechanical properties were then compared among the four TLIF constructs.
RESULTS: With or without a cage, no obvious differences were found in the effect of PEEK rods and Ti rods on the range of motion, adjacent disc stress, and adjacent facet joint force. Compared to Ti rods, PEEK rods increase the average bone graft strain (270.8-6055.2 µE vs. 319.0-8751.6 µE). Moreover, PEEK rods reduced the stresses on the screw-rod system (23.1-96.0 MPa vs. 7.2-48.4 MPa) but increased the stresses on the cage (4.6-35.2 MPa vs. 5.6-40.9 MPa) and endplates (5.7-32.5 MPa vs. 6.6-37.6 MPa).
CONCLUSIONS: Regardless of whether a cage was used for TLIF, PEEK rods theoretically have the potential to serve as an alternative to Ti rods because they may provide certain stability, increase the bone graft strain, and reduce the posterior instrumentation stress, which might promote bony fusion and decrease instrumentation failure.
METHODS: An intact L1-L5 lumbar finite element model was constructed and validated. Accordingly, four TLIF models were developed: (1) Ti rods with a cage; (2) PEEK rods with a cage; (3) Ti rods without a cage; and (4) PEEK rods without a cage. The biomechanical properties were then compared among the four TLIF constructs.
RESULTS: With or without a cage, no obvious differences were found in the effect of PEEK rods and Ti rods on the range of motion, adjacent disc stress, and adjacent facet joint force. Compared to Ti rods, PEEK rods increase the average bone graft strain (270.8-6055.2 µE vs. 319.0-8751.6 µE). Moreover, PEEK rods reduced the stresses on the screw-rod system (23.1-96.0 MPa vs. 7.2-48.4 MPa) but increased the stresses on the cage (4.6-35.2 MPa vs. 5.6-40.9 MPa) and endplates (5.7-32.5 MPa vs. 6.6-37.6 MPa).
CONCLUSIONS: Regardless of whether a cage was used for TLIF, PEEK rods theoretically have the potential to serve as an alternative to Ti rods because they may provide certain stability, increase the bone graft strain, and reduce the posterior instrumentation stress, which might promote bony fusion and decrease instrumentation failure.
摘要：
背景：聚醚醚酮（PEEK）棒在经椎间孔腰椎椎间融合术（TLIF）中是否具有替代钛合金（Ti）棒的潜力尚不清楚，特别是在由于没有笼子而导致前支撑不足的情况下。这项研究的目的是研究在有和没有笼子的TLIF中PEEK棒和Ti棒之间的生物力学差异。
方法：构建并验证了完整的L1-L5腰椎有限元模型。因此，开发了四种TLIF模型：（1）带有保持架的Ti棒；（2）带有保持架的PEEK棒；（3）没有保持架的Ti棒；（4）没有保持架的PEEK棒。然后在四个TLIF构建体之间比较生物力学特性。
结果：有或没有笼子，PEEK棒和Ti棒对运动范围的影响没有明显差异，相邻椎间盘应力，和相邻的小平面联合力。与Ti棒相比，PEEK棒增加平均植骨应变（270.8-6055.2µE与319.0-8751.6µE）。此外，PEEK杆降低了螺杆系统上的应力（23.1-96.0MPa与7.2-48.4MPa），但增加了保持架上的应力（4.6-35.2MPa与5.6-40.9MPa）和端板（5.7-32.5MPa与6.6-37.6MPa)。
结论：无论是否将笼子用于TLIF，PEEK棒理论上有潜力作为钛棒的替代品，因为它们可以提供一定的稳定性，增加骨移植应变，并减少后部仪器的应力，这可能会促进骨融合并减少仪器故障。
方法：构建并验证了完整的L1-L5腰椎有限元模型。因此，开发了四种TLIF模型：（1）带有保持架的Ti棒；（2）带有保持架的PEEK棒；（3）没有保持架的Ti棒；（4）没有保持架的PEEK棒。然后在四个TLIF构建体之间比较生物力学特性。
结果：有或没有笼子，PEEK棒和Ti棒对运动范围的影响没有明显差异，相邻椎间盘应力，和相邻的小平面联合力。与Ti棒相比，PEEK棒增加平均植骨应变（270.8-6055.2µE与319.0-8751.6µE）。此外，PEEK杆降低了螺杆系统上的应力（23.1-96.0MPa与7.2-48.4MPa），但增加了保持架上的应力（4.6-35.2MPa与5.6-40.9MPa）和端板（5.7-32.5MPa与6.6-37.6MPa)。
结论：无论是否将笼子用于TLIF，PEEK棒理论上有潜力作为钛棒的替代品，因为它们可以提供一定的稳定性，增加骨移植应变，并减少后部仪器的应力，这可能会促进骨融合并减少仪器故障。
