螺旋式与环式椎体融合器的生物力学比较

Biomechanical comparison of threaded and non threaded interbody fusion devices

目的 :用生物力学的方法比较螺旋式与环式椎体融合器的初始稳定性和拔出力量。方法 :将2 4个颈椎运动节段 (C4/5 或C6/7) ,根据BMD和不同节段随机分为两组 ,分别用螺旋式BAK C和环式Branti ganI/F ,测试完整模型和固定状态下椎体在前屈 /后伸、左右侧弯和轴向旋转 6种运动状态的稳定性 ,最后进行拔出试验。结果 :BAK C和BrantiganI/F均能增加颈椎的初始稳定性 ,但在效率上无显著性差异。BAK C的拔出力量显著大于BrantiganI/F。结论 :两种椎体融合器的稳定性几乎没有差异。螺旋式融合器具有较大的拔出力量。

Objective:To compare the initial stability and pullout strength of threaded and non threaded cervical interbody fusion devices on human specimens by biomechanical method.Methods:Flexibility of 24 cervical motion segments(two groups)were tested in axial rotation,flexion/extension and lateral bending,intact and after implantation of a cervical fusion device(threaded BKA C and non threaded Brantigan I/F).An implant pullout concluded testing.Changes in range of motion (ROM) were analyzed.Results:Both implants were effectvie at reducing ROM in all directions.Difference was found only just in the ROM of axial rotation.The pullout force of BAK C was significantly differenct between implants.Conclusion:Difference in initial stability between the two implants is rarely found.The threaded implant design has a higher pull out force.