胸腰椎骨折伤椎椎弓根内固定生物力学研究与临床应用

目的通过生物力学测试和临床应用对胸腰椎骨折伤椎椎弓根内固定进行评价。方法取5具新鲜小牛的胸腰椎脊柱标本（T12-L6），制作成严重前中柱损伤模型，应用椎弓根螺钉内固定，测试标本应用不同固定方法后在轴向压缩、屈伸和扭转实验中生物力学稳定性及长短椎弓根螺钉的拔持力，探讨伤椎固定对脊柱稳定性的影响。临床应用伤椎椎弓根内固定治疗胸腰椎骨折19例。结果3种螺钉固定（8钉固定、6钉固定、4钉固定）方式，均能提高骨折失稳后脊柱的各向稳定性。而6钉固定（伤椎固定）与8钉固定对失稳脊柱的各向稳定性的加强程度较为接近（P〉0．05），且均高于4钉固定形式（P〈0．05）。临床观察表明，伤椎椎弓根内固定能利于骨折复位和脊柱生理曲度恢复，同时可有效的维持脊柱稳定性，减少术后伤椎高度丢失。结论生物力学测试证明胸腰椎骨折伤椎椎弓根内固定能加强脊柱的稳定性。临床应用表明伤椎椎弓根内固定在技术操作上是可行的，可更好的维持骨折的稳定，减少伤椎高度的丢失。

A biomechanial study and clinical application of the injured vertebra transpedicular fixation for thoracolumbar fractures

Objective To evaluate biomechanics and clinical application on the transpedicular fixation into the injured vertebra for thoracolumbar fractures.Methods Severe thoracolumbar spinal fracture(T12-L6) were made on 5 cases of fresh calf spinal specimens to compare the stability of 3 kinds of transpedicular fixation by axial compression,bending,rotation as well as axial extraction force of the long and short pedical screws,thus to explore the stability of spine in injured vertebra fixed with pedical screws.There...