桡骨远端解剖型镍钛记忆合金接骨器治疗桡骨远端骨折的生物力学特性

Mechanical calculation and analysis of anatomic inferior extremity of radius Ni-tinol memory connect or treating inferior extremity fracture of radius

目的寻求桡骨远端解剖型镍钛记忆合金接骨器(anatomicinferiorextremityofradiusNi-tinolmemoryconnector,AIER-NTMC)治疗桡骨远端骨折的生物力学特性。方法采用虚功原理及莫尔方法,计算AIER-NTMC固定桡骨远端骨折时在骨折断面及周围所产生的应力并构建应力场。结果桡骨远端AIER-NTMC环抱支受力和环抱支端点处位移δ之间的关系:当接骨器产生8%的弹性变形时,由几何条件δ=4.17mm,P=24N,产生的压强为2.00～2.67MPa。结论AIER-NTMC在骨折线周围的应力分布合理,轴向持骨有利早期骨折端的固定,加压支纵向加压可明显降低骨折线吸收后的应力遮挡率。

Objective To explore the biomechanical ch aracter of anatomic inferior extremity o f radius Ni-tinol memory connector(AI ER-NTMC)treating inferior extremity fractu re of radius.Method By means of ca lculating method,we calculated the stress in or around the fracture face when i nferior extremi ty fracture of radius was fixated wit h AIER-NTMC.Result The r elation between axial encircle stress P developed by encircle part of AIER-N T MC on inferior extremity of radius a nd terminal vertex displacement is,when th e elastic deformation distort produced by encircle part of AIER-NTMC is 8%,i f?=4.17mm,P=24N ,and instensity of pressure is 2.00～2.67MPa .Conclusion The distribution of stress which AIE R-NTMC developed around the f ractur e line is reasonable,axial encircle stress can be of benefit for stabili zing fracture during earlier period,and with the existence of longititud al com pression,which can decrease t he stress block rate after absorption of fracture line.