Lowe Thomas G, Enguidanos Stephen T, Smith David A B, Hashim Shukor, Eule James M, O'Brien Michael F, Diekmann Molly J, Wilson Lucas, Trommeter Julie M
Woodridge Spine Center, Denver, CO, USA.
Spine (Phila Pa 1976). 2005 Feb 1;30(3):311-7. doi: 10.1097/01.brs.0000152376.09501.ae.
Anterior single- and dual-rod instrumented human and ovine thoracolumbar spines, with and without structural interbody support (SIS), were biomechanically tested and compared in flexion, lateral bending, and torsion.
To determine significant differences in global stiffness of the constructs in an attempt to clarify specific indications for each in the treatment of spinal deformities.
Single- and dual-rod anterior systems have been used without any consensus as to indications for one versus the other. The potential added benefit of incorporating SIS and transverse connectors (dual-rod) with these constructs has also not been fully explored.
Four human cadaveric and six ovine spines were instrumented in single- and dual-rod constructs and biomechanically tested intact, postdiscectomy with and without SIS, with single- and dual-rod constructs, and with and without transverse connectors (ovine only). Biomechanical testing modes were flexion, lateral bending, and torsion.
In the human cadaveric specimens, testing in flexion revealed that SIS was the major contributing factor for construct stiffness. In lateral bending, stiffness of single- and dual-rod constructs with and without SIS was equivalent. In torsion, both single- and dual-rod instrumentation and SIS appeared to contribute to global stiffness. In ovine specimens, dual rods were stiffer than single-rod constructs and SIS played only a minor role. Transverse connectors appeared to significantly stiffen dual-rod constructs in torsion only.
Dual-rod constructs with SIS appear to be the best combination for providing stiffness in anterior instrumentation. The addition of cross-links to anterior constructs does not appear to increase stiffness except in torsion.
对有和没有结构性椎间支撑（SIS）的人体和绵羊胸腰椎前路单棒和双棒内固定脊柱进行生物力学测试，并在屈曲、侧弯和扭转状态下进行比较。
确定这些内固定结构在整体刚度上的显著差异，以明确各自在脊柱畸形治疗中的具体适应证。
单棒和双棒前路系统的使用在适应证方面尚无共识。将SIS和横向连接器（双棒）纳入这些结构可能带来的额外益处也尚未得到充分探索。
对4具人类尸体和6只绵羊的脊柱进行单棒和双棒内固定，并在完整状态、椎间盘切除术后有和没有SIS的情况下，以及有和没有横向连接器（仅针对绵羊）的单棒和双棒内固定结构下进行生物力学测试。生物力学测试模式包括屈曲、侧弯和扭转。
在人类尸体标本中，屈曲测试显示SIS是影响结构刚度的主要因素。在侧弯时，有无SIS的单棒和双棒结构的刚度相当。在扭转时，单棒和双棒内固定以及SIS似乎都对整体刚度有贡献。在绵羊标本中，双棒比单棒结构更硬，SIS仅起次要作用。横向连接器似乎仅在扭转时显著增强双棒结构的刚度。
带有SIS的双棒结构似乎是前路内固定中提供刚度的最佳组合。除了扭转外，在前路结构中添加交联似乎不会增加刚度。
