Biomechanical role of lumbar spine ligaments in flexion and extension: Determination using a parallel linkage robot and a porcine model
Biomechanical role of lumbar spine ligaments in flexion and extension: Determination using a parallel linkage robot and a porcine model
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DOI：
10.1097/00007632-200406010-00010
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发表时间：
2004-06-01
期刊：
影响因子：
3
通讯作者：
Dickey, JP
中科院分区：
文献类型：
--
作者：
Gillespie, KA;Dickey, JP
研究设计。猪腰椎标本受载于纯力矩的屈曲和伸展。通过一系列的切除手术来量化单个脊柱单元的屈曲和伸展阻力。目的：确定单个脊柱后韧带，包括棘上韧带和棘间韧带之间的相互连接，在抵抗施加在腰椎上的屈伸扭矩方面的生物力学贡献。许多实验研究已经进行了重复的连续切除测试，以确定脊柱韧带的作用。大多数研究没有在整个试验过程中保持运动学，因此这些研究评估了受伤脊柱的运动学和动力学，而不是描绘单个韧带的力学。利用并联机器人对猪脊柱标本的L4-L5运动路径进行了学习和回放。每个标本测试6次，按如下顺序进行切除：棘上韧带和棘间韧带之间完整的切断连接，棘上韧带切除，棘间韧带去除，黄韧带切断，小关节切除。每一次测试都重复了运动学路径，因此，试验之间的载荷变化反映了被切割/移除结构的力学。棘上韧带和棘间韧带之间的相互作用是造成猪腰椎屈曲阻力的重要因素，可抵抗10.5%的峰值屈曲力矩。这一贡献与棘间韧带(11.3%)相似，几乎与冈上韧带(14%)和小关节(14.2%)一样大。棘上/棘间韧带复合体对屈曲运动的阻力贡献最大(35.9%)，其次是椎间盘(25.2%)和黄韧带(24.7%)。唯一牵涉到抵抗伸展的结构是小关节复合体、间盘，可能还有棘突。棘上/棘间韧带复合体是猪腰椎抵抗外加屈曲力矩的最大因素。
Study Design. Porcine lumbar spine specimens were cyclically loaded in flexion and extension with a pure moment. The resistance to flexion and extension of the individual spinal elements was quantified using a sequential resection procedure.Objective. To determine the biomechanical contribution of the individual posterior spinal ligaments, including the interconnections between the supraspinous and interspinous ligaments, to resisting flexion-extension moments applied to the lumbar spine.Summary of Background Data. Numerous experimental studies have performed repeated tests with sequential resection to determine the role of spinal ligaments. Most studies have not maintained the kinematics across trials, and therefore these studies have assessed the kinematics and kinetics of injured spines rather than delineating the mechanics of individual ligaments.Methods. The L4-L5 motion pathway for pure moment loading (between in 16 Nm of flexion and 12 Nm of extension) of porcine spinal specimens was learned and replayed using a parallel-linkage robot. Each specimen was tested 6 times, with sequential resections performed as follows: intact, cut interconnections between the supraspinous and interspinous ligaments, supraspinous ligament removed, interspinous ligament removed, ligamentum flavum cut, and facet joints removed. The kinematic pathway was repeated for each of these tests, and, accordingly, the changes in loads between trials reflected the mechanics of the cut/removed structures.Results. The interaction between the supraspinous and interspinous ligaments is a significant contributor to the flexion resistance of the porcine lumbar spine, resisting 10.5% of the peak flexion moment. This contribution is similar to the interspinous ligament (11.3%) and almost as large as the supraspinous ligament (14%) and facet joints (14.2%). The supraspinous/interspinous ligament complex was the largest contributor to the resistance of flexion motion (35.9%), followed by the intervertebral disc (25.2%) and the ligamentum flavum (24.7%). The only structures involved in resisting extension were the facet joint complexes, intervertebral disc, and possibly the spinous processes.Conclusions. The supraspinous/interspinous ligament complex is the largest contributor to resisting applied flexion moments in the porcine lumbar spine.