一例金属接骨螺钉断裂原因分析

Analysis the Reason of 1 Case With Fracture Reason of Metal Bone Screw

目的研究探讨一例金属接骨螺钉断裂原因,为今后金属接骨螺钉的实际应用提供参考。方法回顾性分析本院收治的1例外科手术治疗骨折并行金属接骨板固定患者,患者术后1月出现金属接骨螺钉断裂失效情况,对此采取现代试验检测技术进行宏观观察、金属化学成分检测、硬度试验、显微组织观察及表面质量检测进行分析。结果螺钉断裂主因是由材质表面存在的裂纹,造成螺距根部应力集中爆发,使之出现较作用力后扩展表面裂纹,造成受力不均断裂。结论金属接骨螺钉断裂主因材质本身存在的不连续裂纹,在钢板连接接骨固定后,循环作用力因素影响,不断加剧裂纹扩张,造成金属螺纹钉发生疲劳性断裂。笔者结合光学金相显微镜技术及电子探针设备辅助对螺纹断口原因进行分析,明确螺钉断裂因素,为今后金属接骨螺钉的实际应用提供参考。

Objective To investigate a case of metal bone screw fracture, and provide a reference for the practical application of metal bone screw in the future. Methods A retrospective analysis of our hospital 1 cases of surgical treatment of fracture of parallel metal plate fixation patients, patients postoperative 1 month appear metal bone screw fracture failure. For this to take modern test technology of macro observation, metal chemical composition test, hardness test and microstructure observation organization and surface quality detection are analyzed. Results Screw fracture is mainly caused by the cracks on the surface of the material, which causes the stress concentration at the root of the pitch, which causes the crack to crack, which is caused by the uneven stress. Conclusion Metal bone screw fracture cause of material itself and the discontinuous crack, in the plate connection after osteosynthesis and circulating acting force factors, increasing the crack expansion, caused by metal screw nail occurred in fatigue exercise. Based on optical metallographic microscope and electron probe auxiliary equipment of screw fracture cause analysis and clear screw breakage factors, to provide a reference for the future practical application of metal bone screw.