基于有限元的第5掌骨颈骨折钢板螺钉内固定的生物力学分析

Biomechanical Analysis of Plate Internal Fixation Treating the Fifth Metacarpal Neck Fracture based on Finite Element Method

目的:应用有限元方法建立三种不同的治疗第5掌骨颈骨折的钢板螺钉内固定模型,比较三种模型的生物力学稳定性,为第5掌骨颈骨折的临床早期功能康复提供参考。方法:选取一名健康青年志愿者,将CT扫描数据导入三维有限元软件建立第5掌骨颈骨折模型,并选取三种钢板螺钉内固定方法进行骨折固定。对三种模型施加外力荷载并进行生物力学有限元分析,对比骨折断端的最大位移和钢板螺钉的应力分布情况。结果:方法一、二、三的第5掌骨骨折端的最大位移分别为0.189775 mm、0.181428 mm、0.224299 mm,以方法二的骨折端位移最小;内固定材料的最大应力分别为1.20 KPa、1.00 KPa、1.39 KPa,以方法二的钢板螺钉应力最小。结论:采用近端三颗螺钉远端两颗螺钉的直型钢板内固定方法治疗第五掌骨颈骨折的生物力学稳定性更好,术后早期功能锻炼的安全性更高,是治疗第5掌骨颈骨折的理想内固定方法。

Objective： To establish three kinds of internal fixation plate models by dimensional finite element method（FEM）, com- pare their stabilities and provide references for the early clinical function rehabilitation of fifth metacarpal neck fracture. Methods： A healthy, male volunteer was chosen and got CT scan images, using three dimensional finite element software to simulate internal fixation models of the fifth metacarpal neck fracture. Three methods of plates were used to fix the fracture. The maximum relative displacement of fracture sections and maximum stress of plates were observed and compared between three kinds of models. Results： In the three meth- ods of plates, The maximum displacements of fracture sections in group 1, 2, 3 were 0.189775mm, 0.181428mm, 0.224299mm and the maximum stress of plates were 1.20KPa, 1.00KPa, 1.39KPa respectively. The second method had the smallest displacement and stress. Conclusions： Straight plate with three screws in the proximal and two in the distal could get more stability and safety for the early func- tion rehabilitation of the fifth metacarpal neck fracture. It was an ideal method for the fifth metacarpal neck fracture.