Suture broken, knot slipping and tissue tearing are the main reasons of wound closure failure in clinical operation. Based on this, we simulated the suturing and healing operation by using a biological materials testing machine and investigated the tensile properties before and after knotting, relaxation property and friction property of three common sutures: silk, polyglactin 910 and polypropylene. Results show that the tensile property decreased after knotting. The tensile strength of polyglactin 910 and elongation of polypropylene were the largest. During the relaxation process, the sutures relaxed the most in the first 2 hours. The relaxation from less to more was: polyglactin 910, silk and polypropylene. Coating or monofilament could obviously reduce the surface roughness of sutures, and thus reduce the friction force of the suture-suture interface. The friction force of the suture-suture interface increased with the increasing load but did no change with the increasing velocity. The results can provide an important theoretical basis for the optimizations of suture design and knotting operation.
在临床操作中，手术缝合线的断裂、结的滑脱和缝合线对组织的撕裂是造成伤口缝合失效的主要原因。基于此，本文在生物材料试验机上模拟缝合打结过程，研究了丝线、聚乳糖酸 910 缝合线和聚丙烯缝合线打结前后的拉伸、松弛和线-线界面的摩擦性能。结果表明，打结使缝合线的拉伸性能降低。其中聚乳糖酸 910 缝合线拉伸强度最大，聚丙烯缝合线延伸率最大；在松弛过程中，缝合线在初始 2 h 松弛量最大，松弛量从小到大为：聚乳糖酸 910 缝合线、丝线、聚丙烯缝合线。涂层和单丝结构均能有效降低缝合线表面粗糙度，从而减小线-线界面的摩擦力；线-线界面的摩擦力随载荷增加而增加，而与摩擦速度无关。研究结果为优化缝合线设计和缝合打结操作提供了重要的理论基础。.
Keywords: friction behavior; relaxation; surface morphology; suture; tensile.