Department of Orthopedics and Spine Surgery, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, Anhui, 230022, China.
Laboratory of Spinal and Spinal Cord Injury Regeneration and Repair, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Hefei, Anhui, 230022, China.
BMC Musculoskelet Disord. 2024 Aug 24;25(1):664. doi: 10.1186/s12891-024-07796-1.
There is a dearth of comprehensive research on the stability of the spinal biomechanical structure when combining Oblique Lumbar Interbody Fusion (OLIF) with internal fixation methods. Hence, we have devised this experiment to meticulously examine and analyze the biomechanical changes that arise from combining OLIF surgery with different internal fixation techniques in patients diagnosed with degenerative lumbar spondylolisthesis.
Seven validated finite element models were reconstructed based on computed tomography scan images of the L3-L5 segment. These models included the intact model, a stand-alone (S-A) OLIF model, a lateral screw rod (LSR) OLIF model, a bilateral pedicle screw (BPS) OLIF model, an unilateral pedicle screw (UPS) OLIF model, a bilateral CBT (BCBT) OLIF model, and an unilateral CBT(UCBT) OLIF model. The range of motion (ROM), as well as stress levels in the cage, L4 lower endplate, L5 upper endplate, and fixation constructs were assessed across these different model configurations.
S-A model had the highest average ROM of six motion modes, followed by LSR, UPS, UCBT, BPS and BCBT. The BCBT model had a relatively lower cage stress than the others. The maximum peak von Mises stress of the fixation constructs was found in the LSR model. The maximum peak von Mises stress of L4 lower endplate was found in the S-A model. The peak von Mises stress on the L4 lower endplate of the rest surgical models showed no significant difference. The maximum peak von Mises stress of the L5 upper endplate was found in the S-A model. The minimum peak von Mises stress of the L5 upper endplate was found in the BCBT model. No significant difference was found for the peak von Mises stress of the L5 upper endplate among LSR, BPS, UPS and UCBT models.
Among the six different fixation techniques, BCBT exhibited superior biomechanical stability and minimal stress on the cage-endplate interface. It was followed by BPS, UCBT, UPS, and LSR in terms of effectiveness. Conversely, S-A OLIF demonstrated the least stability and resulted in increased stress on both the cage and endplates. Combining OLIF with BCBT fixation technique enhanced biomechanical stability compared to BPS and presented as a less invasive alternative treatment for patients with degenerative lumbar spondylolisthesis.
目前针对腰椎前侧融合术（OLIF）联合内固定方式对脊柱生物力学结构稳定性的综合研究较为匮乏。因此，我们设计了这项实验，旨在详细检查和分析在退行性腰椎滑脱症患者中，OLIF 手术与不同内固定技术结合后产生的生物力学变化。
基于 L3-L5 节段的计算机断层扫描图像，重建了 7 个经过验证的有限元模型。这些模型包括完整模型、单独（S-A）OLIF 模型、侧方螺钉棒（LSR）OLIF 模型、双侧椎弓根螺钉（BPS）OLIF 模型、单侧椎弓根螺钉（UPS）OLIF 模型、双侧皮质骨骨栓（BCBT）OLIF 模型和单侧皮质骨骨栓（UCBT）OLIF 模型。评估了这些不同模型构型的活动范围（ROM）和 cage、L4 下终板、L5 上终板以及固定结构的应力水平。
S-A 模型在六种运动模式下具有最高的平均 ROM，其次是 LSR、UPS、UCBT、BPS 和 BCBT。BCBT 模型的 cage 应力相对较低。固定结构的最大 von Mises 峰值应力出现在 LSR 模型中。S-A 模型的 L4 下终板最大 von Mises 峰值应力。其余手术模型的 L4 下终板 von Mises 峰值应力无显著差异。S-A 模型的 L5 上终板 von Mises 峰值应力最大。BCBT 模型的 L5 上终板 von Mises 峰值应力最小。LSR、BPS、UPS 和 UCBT 模型的 L5 上终板 von Mises 峰值应力无显著差异。
在六种不同的固定技术中，BCBT 表现出更好的生物力学稳定性和 cage-endplate 界面的最小应力。其次是 BPS、UCBT、UPS 和 LSR。相反，S-A OLIF 表现出最低的稳定性，导致 cage 和终板的应力增加。与 BPS 相比，OLIF 联合 BCBT 固定技术增强了生物力学稳定性，为退行性腰椎滑脱症患者提供了一种侵入性较小的替代治疗方法。
