带有BMP中空侧孔新型椎弓根钉作用特点的实验研究

Research for application features of novel pedicle screw with BMP and lateral pore

目的探讨带有MBP中空侧孔新型椎弓根钉的作用特点,明确其在腰椎骨折模型中内固定的效果。方法比较两种不同椎弓根钉的生物力学测试,包括轴向最大拔出力,垂直压缩刚度及极限压缩强度。采用X线摄片及CT观察伤椎内固定后的大体形态,比较两组中伤椎前缘高度及椎管正中矢状径(MD)的差异。结果新型椎弓根钉组其平均轴向最大拔出力明显高于普通型组,差异有统计学意义(P<0.05);两种椎弓根钉行椎弓根钉固定后即刻状态的整体刚度差异无统计学意义(P>0.05),极限抗压强度差异有统计学意义(P<0.05)。普通型与新型椎弓根钉相比较,其平均前缘高度及伤椎平均MD值差异均有统计学意义(P<0.05)。结论新型椎弓根钉内固定的稳定性明显优于普通型椎弓根钉,值得推广应用。

Objective To investigate features of novel lumbar pedicle screw and find effect of it in Jmhar fracture model. Methods Specimens were divided into two groups： novel pedicle screw and common pedicle screw. The biomechanics of the maximum pullout strength, the stiffness modulus of immediately state after reconstruction and the ultimate compressive strength were compared. The morphological changes including Cobb angle and median diameter in two different groups were observed by using X-Ray and CT scan. Results The maximum pullout strength was higher in novel than common, with significant difference between two groups （P 〈0.05）; There were differences in values of the ultimate compressive strength of immediately state after reconstruction, Cobb angle and median diameter between two groups. There was no difference in the stiffness modulus between two groups （P 〉0.05）. Conclusion The steadiness of novel pedicle screw is better than common pedicle screw and its feature is obvious. So it should be used for treating lumbar fracture.