Shih Chun-Che, Shih Chun-Ming, Su Yea-Yang, Lin Shing-Jong
Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei 112, Taiwan, ROC.
Eur J Cardiothorac Surg. 2004 May;25(5):812-8. doi: 10.1016/j.ejcts.2003.11.043.
To understand the potential fracture mechanism of sternal wires, we collected extracted stainless steel sternal wires from patients with sternal dehiscence following open-heart operations. Surface alterations and fractured ends of sternal wires were inspected and analyzed.
Eight fractured and 12 non-fractured wires extracted from five patients (closure method: figure-of-eight or straight twisted; two without and three with mediastinitis) with mean implantation interval of 13.2+/-4.2 days (range 8-20 days) were studied by various techniques. The extracted wires were cleaned and the fibrotic tissues were removed. Irregularities and fractured ends were assayed by scanning electron microscopy and energy dispersive X-ray analysis (EDXA).
All examined fractured wires showed the presence of severe transversal cracks and crevice corrosion. EDAX revealed aluminum oxide inclusion on the fractured surface.
The synergic effect of stress and poor wire quality could be the precursors of material failure for the sternal wire.
为了解胸骨钢丝潜在的断裂机制，我们收集了心脏直视手术后发生胸骨裂开患者体内取出的不锈钢胸骨钢丝。对胸骨钢丝的表面变化和断裂端进行了检查与分析。
研究了从5例患者（闭合方法：8字缝合法或直扭法；2例无纵隔炎，3例有纵隔炎）取出的8根断裂钢丝和12根未断裂钢丝，平均植入间隔为13.2±4.2天（范围8 - 20天）。取出的钢丝进行清洁并去除纤维化组织。通过扫描电子显微镜和能量色散X射线分析（EDXA）检测不规则处和断裂端。
所有检查的断裂钢丝均显示存在严重的横向裂纹和缝隙腐蚀。能谱分析显示断裂表面有氧化铝夹杂物。
应力与钢丝质量不佳的协同作用可能是胸骨钢丝材料失效的先兆。
