不同标记线制备方法对脊柱连接棒疲劳性能的影响

Effects of Different Preparation Methods of Marking Lines on Fatigue Properties of Spinal Rods

目的 研究不同标记线制备工艺对脊柱后路内固定系统连接棒疲劳性能和系统压缩疲劳性能的影响。方法 根据YY/T 0119.4—2014标准对脊柱连接棒进行4点弯曲疲劳测试。在一定应力作用下,依据YY/T 0857—2011对激光标记线连接棒和双色彩氧标记线连接棒进行系统压缩疲劳试验。结果 在715 MPa应力下,自制激光标记线连接棒和竞品厂家激光标记线连接棒疲劳寿命较无标记线连接棒分别下降了95%和98%;与未标记连接棒相比,激光标记连接棒疲劳强度由742 MPa下降至342 MPa,降低了54%。双色彩氧连接棒的疲劳寿命和疲劳强度与无标记线连接棒相当。双色彩氧连接棒系统压缩疲劳强度较激光标记连接棒提高约20%。结论 激光制备标记线显著降低了脊柱连接棒的疲劳性能和系统的压缩疲劳强度,改进的双色彩氧工艺制备标记线对连接棒的疲劳性能无影响,能有效降低临床断裂风险,为连接棒的性能改善和工艺开发提供参考。

Objective To study the effects of different marking line preparation techniques on fatigue properties of rod and compression fatigue properties of posterior spine internal fixation system.Methods According to YY/T 0119.4—2014 standard,four-point flexural fatigue test was performed on the spinal rod.According to YY/T 0857—2011,systematic compression fatigue tests under certain stress were carried out on laser marking line rod and dual-color anodized marking line rod.Results Under 715 MPa stress,the fatigue life of the self-made laser marking line rod and the competitor's laser marking line rod is reduced by 95% and 98% respectively compared with the unmarked rod,and the fatigue strength of the laser marking line rod decreased by 54% from 742 MPa to 342 MPa,compared with unmarked rod.The fatigue life and strength of the dual-color anodized marking line rod are similar to that of the unmarked rod.The compression fatigue strength of the dual-color anodized marking line rod system was 20% higher than that of the laser marking rod.Conclusions Laser preparation of marking line significantly reduces the fatigue performance of the spinal rod and the compressive fatigue strength of the system.The improved dual-color anodized marking line technology has no effects on the fatigue performance,and can effectively reduce the risk of clinical fracture,providing a reference for the performance improvement and process development of the spinal rod.