目的用三维有限元方法对医用316L不锈钢接骨板、螺钉及股骨进行应力计算,最终分析316L不锈钢接骨板对股骨的应力遮挡效应。方法首先建立医用316L不锈钢接骨板、螺钉及股骨的三维几何模型;网格划分后建立对应的三维有限元模型;在定义材料属性的基础上,加载边界条件,对站立位状态下的接骨板及螺钉强度进行有限元计算,同时分析股骨应力遮挡问题。结果通过对螺钉未加压状态和加压状态下股骨所受应力与站立位时正常股骨应力的对比,得出医用316L不锈钢接骨板及螺钉对股骨的应力遮挡效应。结论医用316L不锈钢接骨板及螺钉对股骨产生明显的应力遮挡效应,仅靠螺钉加压对应力遮挡效应的降低作用有限。本文建立的接骨板对股骨应力遮挡的分析方法可广泛应用于其他骨骼骨折应力遮挡的分析。
Objective To calculate the stress of medical 316L stainless steel plate, screws and femur by 3D finite element method, to analyze the stress shielding effect of 316L stainless steel plate on femur. Methods Firstly, we established 3D geometric model of medical 316L stainless steel plate, screws and the femur. The corresponding 3D finite element model was built after the solid meshing. Then, on the basis of the definition of material properties, we loaded the boundary conditions. At last, we made finite element analysis of the 316L stainless steel plate and screws in the standing posture and analyzed the femoral stress shielding effect. Results During standing posture, the stresses of plate and screws were analyzed by the finite element method, and the femoral stress shielding effect was analyzed. Conclusions The femoral stress shielding effect was obvious, and adding pressure on the screws was not effective. This analytical method for femoral stress shielding might be widely used in the stress shielding analyses for other bone fractures.