腰椎皮质骨通道螺钉固定系统的生物力学实验

摘要

BACKGROUND:Santoni put forward the cortical bone trajectory technology by changing the traditional pedicle screw placement for lumbar internal fixation in order to obtain better control of the screw and bone in 2009. OBJECTIVE:To analyze biomechanical stability of cortical bone trajectory system in the lumbar fusion. METHODS:Twenty fresh newborn calf L3/4, L5/6 motion segment specimens were obtained, and their ranges of motion were detected under different states, as normal controls. Subsequently, twenty samples were divided into cortical bone trajectory screw group and traditional pedicle screw group, which underwent cortical bone trajectory screw fixation combined with posterior lumbar fusion and traditional pedicle screw fixation combined with posterior lumbar fusion, respectively. Without destruction, ranges of motion were detected under different states in both groups. In the revision group, after the test in the traditional pedicle screw group, screw was withdrawn, and cortical bone trajectory screw was used to detect its range of motion under different states. RESULTS AND CONCLUSION:Ranges of motion at bending to the left and right, anteflexion, posterior extension and axial rotation were significantly lower in the cortical bone trajectory screw group and traditional pedicle screw group than in the normal control group (P<0.05). No significant difference in bending to the left and right, anteflexion, posterior extension and axial rotation was detected between the cortical bone trajectory screw and revision groups and traditional pedicle screw group (P>0.05). These results confirmed that cortical bone trajectory technology combined with posterior lumbar fusion can obtain identical stability as the traditional pedicle screw fixation combined with posterior lumbar fusion. Simultaneously, it is a new choice for revision after traditional pedicle screw fixation.%背景：通过改变现行的传统椎弓根螺钉置入方式，以获得更佳的螺钉与骨的把持力，2009年Santoni等提出将皮质骨通道技术应用于腰椎内固定。　　目的：分析皮质骨通道螺钉固定系统在腰椎间融合固定时的生物力学稳定性。　　方法：获取20个新鲜初生小牛L3/4、L5/6运动节段标本，在非破坏状况下检测其不同状态下的活动度，作为正常对照；随后将20个标本分为皮质骨通道螺钉组与传统椎弓根螺钉组，分别进行皮质骨通道螺钉固定辅助腰椎后路椎间融合固定、传统椎弓根螺钉辅助腰椎后路椎间融合固定，在非破坏状况下检测两组不同状态下的活动度；翻修组为传统椎弓根螺钉组测试结束后撤钉，改用皮质骨通道螺钉固定，检测其不同状态下的活动度。结果与结论：皮质骨通道螺钉组、传统椎弓根螺钉组左右弯曲、前屈、后伸、轴向旋转运动状态下的活动度较正常对照组明显降低(P<0.05)，皮质骨通道螺钉组、翻修组左右弯曲、前屈、后伸、轴向旋转运动状态下的活动度与传统椎弓根螺钉组比较差异无显著性意义(P>0.05)。结果表明，椎弓根皮质骨通道技术辅助腰椎后路融合固定可获得与传统椎弓根螺钉辅助腰椎后路融合固定相同的稳定性，同时是传统椎弓根螺钉固定失败后翻修的一种新选择。