股骨干骨折的接骨板内固定生物力学实验设计

Design of mechanical experiment on plate internal fixation for femoral shaft fracture

以股骨干骨折的接骨板内固定方式为研究对象,开发了一个综合性的生物力学实验。在传统静态应变仪采集应变片数据的基础上,结合三维数字散斑动态应变测量系统分析接骨板固定骨折的股骨在压力载荷的作用下发生的变形、接骨板及骨上的应力分布特点。实验结果显示:当螺钉数量较少时,接骨板的弯曲变形增大,增加了接骨板塑性变形及疲劳断裂的可能性;骨折断口下侧的螺钉的应力明显高于上侧的螺钉,因过载导致塑性变形及疲劳断裂的可能性大。该实验有利于提高学生分析处理问题能力,激发了学生的科研积极性。

A comprehensive biomechanical experiment is developed to study the plate internal fixation of femoral shaft fracture. On the basis of strain gauge data collected by traditional static strain gauge,and in combination with 3D digital speckle dynamic strain measurement system,the deformation and stress distribution characteristics of femur fixed with plate under pressure load are analyzed. The experimental results show that when the number of screws is small,the bending deformation of the plate increases,which expands the possibility of plastic deformation and plate fatigue fracture. The stress of the screw on the lower side of fracture is obviously higher than that on the upper side,and the possibility of plastic deformation and fatigue fracture due to overload is high. The experiment is helpful for improving the students’ ability to analyze and deal with problems and stimulate their enthusiasm for scientific research.