仿生低阻力医用缝合针设计与刺穿过程的数值模拟

Design of biomimetic low-drag medical suture needle and numerical simulation on penetrating process

针对医用缝合针缝合过程产生的刺穿阻力会对软组织造成损伤且刺穿阻力越大损伤程度越高的问题,提出了低阻力医用缝合针仿生模型。以鼠李科植物酸枣树(Ziziphus jujube)钩刺为仿生原型设计针尖锥度/半径、针体曲率等,并在针体表面设置竖条纹凹槽,形成仿生低阻力医用缝合针;采用LS-DYNA软件与库伦摩擦模型进行仿生低阻力医用缝合针刺穿皮肤软组织过程的数值模拟。结果显示,竖条纹凹槽针体可使仿刺尖锥度/半径与刺体曲率的低阻力医用缝合针的刺穿阻力降低34.24%-58.48%,仿刺尖锥度/半径的低阻力医用缝合针的刺穿阻力降低30.26%-49.86%;采用数控精细加工技术制备仿生低阻力医用缝合针并进行功效测试,其刺穿带皮猪肉过程的刺穿阻力可降低43.02%。研究结果明确了医用缝合针形貌结构特征对刺穿阻力的影响规律,为低阻力医用缝合针仿生设计提供了理论参考。

Aiming at the problem that the puncture drag of the medical suture needle produced in the suture process will cause damage to the soft tissue, and the greater the puncture drag is, the higher the damage degree is, a biomimetic model of low-drag medical suture needle was proposed.The biomimetic prototype of low-drag medical suture needle was constructed, and its needle tip taper/radius and needle body curvature were designed based on the morphological/structural characteristics of the thorn in Ziziphus jujube,and vertical stripe grooves were set on the needle body, forming the biomimetic model of low-drag medical suture needles.LS-DYNA software and Coulomb friction model were used to simulate the process of biomimetic low-drag medical suture needle penetrating skin soft tissue.The results show that the needle body with vertical stripe grooves can reduce the puncture drag of low-drag medical suture needle with the thorn tip taper/radius and the thorn body curvature by 34.24%~58.48%,and can reduce the puncture drag of low-drag medical suture needle with the thorn tip taper/radius by 30.26%~49.86%.The biomimetic low-drag medical suture needles were fabricated and their puncture drag was experimentally tested.In the penetrating process, the puncture drag of biomimetic low-drag medical suture needle was reduced by 43.02%.The results reveal the influence mechanism of the morphological/structural characteristics of medical suture needle on its puncture drag, and provide a theoretical reference for the biomimetic design of low-drag medical suture needle.