短节段椎弓根钉固定术的生物力学研究  

Biomechanic research on short-segment posterior pedicle screw fixation

作　　者：陈艺[1] 白波[1] 孙辉 吴景明[1] 廖壮文[1] 田联房[3] 邓国勇[3] 吴梅祥[1] 

机构地区：[1]广州医学院第一附属医院骨科,510120 [2]佛山市南海区人民医院骨科 [3]华南理工大学自动化科学与工程学院

出　　处：《中华创伤杂志》2010年第1期39-43,共5页Chinese Journal of Trauma

基　　金：国家自然科学基金资助项目（30570458）;广东省自然科学基金资助项目（05006530）;广州市卫生局资助项目（2009-YB-144）

摘　　要：目的基于计算机控制的六自由度机器人全新试验装置，更好地模拟人体在自然状态下的复杂运动。比较3椎体4枚、5枚与6枚椎弓根钉固定术治疗胸腰椎爆裂骨折的生物力学稳定性效果。方法采用6具国人新鲜脊柱尸体标本（T11～L3），椎体切除法模拟失去前柱支持、完令不稳定L1椎体爆裂骨折。试验分跨节段3椎体4枚椎弓根钉固定组、3椎体5枚椎弓根钉固定组和3椎体6枚椎弓根钉固定组。应用混合力-位移控制加载的六自由度机器人全新试验装置对标本进行前屈，后伸，左侧弯、右侧弯及左轴向旋转和右轴向旋转6种运动方式，对固定节段（T11～L3）的运动范围（ROM）进行测试并计算刚度值，比较各组间差异：结果随着螺钉数的增加．固定节段（T11～L3）的运动范围逐渐减小，刚度逐渐增大；轴向旋转时，6钉组、5钉组的运动范围小于4钉组（P〈0．05），6钉组刚度大于4钉组（P〈0．05）、5钉组刚度与4钉组的差异无统计学意义（P〉0．05）；6种不同加载方向下，6钉组与5钉组的运动范围与刚度的差异均无统计学意义（P〉0．05）；屈伸、侧弯状态下，3种不同固定方式之间差异不具有统计学意义（P〉0．05）。结论对于胸腰椎爆裂骨折，经骨折椎3椎体6枚钉或5枚钉的固定方式可以提高生物力学稳定性，稳定效果要优下传统的4枚钉固定，而6枚钉与5枚钉固定稳定性的差异不明显。Objective To compare the stability effect of the fixation segment using the new test system based robotics to simulate the complex human movement at natural state about the three-level fixation by using four, five or six pedicle screws in treatment of thoracolumbar burst fractures. Methods Six human eadaveric spines were dissected from T11 -L3. The inferior half part of L1 vertebral bodies and T11-L2 discs were resected to mimic an unstable L1 burst fracture with loss of anterior column support. Specimens were tested in accordance with the following order： intact, 4,5 and 6 pedicle screws fixation at the three-level fixation. The range of motion （ROM） of the fixation segment （T11 -L3 ） was measured with the six-freedom degree robotics system controlled by mixed force and displacement during flexion, extension, lateral bending and axial torsion, when the stiffness was calculated. One-way statistical analysis was used for analyzing the collected data. Results With increased number of screws, the ROM of the fixation segment （T11-L3 ） was gradually decreased and the stiffness gradually increased. The ROM under axial rotation of six and five screws group became smaller than four screws group （ P 〈 0.05）. The stiffness under axial rotation of six screws group was higher than four screws group （ P 〈 0.05）. There was no statistical difference between five screws group and four screws group in regard of the stiffness in axial rotation （ P 〉 0.05 ）. There were no significant differences in ROM and stiffness under six different loading directions between six screws group and five screws group （P 〉 0.05 ）. No statistical difference was observed for three fixation modes in aspects of ROMs and stiffness under flexion-extension or lateral bending （P 〉 0. 05）. Conclusions Three-level fixation of burst fractures with five or six screws offers improved biomechanical stability compared with traditional four screws fixation. But the difference is insignificant between six and five screws f

关 键 词：脊柱骨折 生物力学 内固定器 机器人 

分 类 号：R687.3[医药卫生—骨科学] R318.01[医药卫生—外科学]