镍钛记忆合金腕骨三角融合器有限元分析

Finite element analysis of NiTi Shape Memory Alloy STT Arthrodesis Concentrator (NT-STTAC)

目的通过对腕舟骨、大小多角骨数字化重建,并运用大型有限元分析软件对两种镍钛记忆合金腕骨三角融合器(NT-STTAC)进行生物力学分析,为器械的临床应用提供参考。方法将IGS格式的两种融合器的三维图导入大型有限元分析软件ANSYS中,赋予相关材料力学性质,建立NT-STTAC有限元模型,并根据腕关节掌屈背伸时NT-STTAC受力情况模拟加载,分析比较模型各部分的不同应力、应变值及分布和压缩刚度的差异。结果在模拟NT-STTAC受力的情况下,分别从抗轴向拉伸力和抗轴向压缩载荷稳定性两方面分析,总体观察:实心的NT-STTAC刚度值在一定范围内稍强于镂空的镍钛记忆合金腕骨三角融合器(HNT-STTAC),在其它节点位置两者基本持平,差别不明显。结论两种三角融合器的刚度值接近,整体力学稳定性基本持平,在一定范围内均能满足术后腕关节功能锻炼,HNT-STTAC可以很好的应用于临床。

Objective To analyze biomechanical characteristics of HNT-STTAC and NT-STTAC on digital images of scaphoid, trapezium and trapezoid finished by finite element software, and provide basis for clinical application. Methods The three-dimensional maps of two kinds of NT-STTAC were loaded into the finite element soft-ware ANSYS, for analyzing mechanical properties of them. The difference of stress, strain value, distribution and compression stiffness were measured and compared, at the wrist position of palm flex and back-stretch. Results Under the simulation of NT-STTAC force, mechanical stability under the resistance of axial tensile force and axial compression, were analyzed. Stiffness value of Solid NT - STTAC in the certain scope, was better than HNT-STTAC. However, stiffness value had no difference at other positions. Conclusions According to our work, stiffness parameters and mechanical stability of HNT-STTAC and NT-STTAC have no difference. HNT - STTAC is reliable for clinical application.