距骨颈骨折螺钉固定的三维有限元分析

摘要

目的 通过三维有限元法对距骨颈骨折不同螺钉内固定方式进行对比评价,比较不同内固定方式生物力学稳定性,为临床应用提供理论依据.方法 利用CT扫描数据,根据距骨颈骨折不同的内固定方式,建立距骨颈骨折内固定三维有限元模型,研究不同内固定von Mises应力分布和骨折面接触压力及张开位移,分析骨折固定后生物力学稳定性.结果 获得距骨颈骨折不同内固定固定有限元模型,静止站立和踝关节背伸时,不同内固定生物力学稳定性不同,双螺钉由前向后固定螺钉的应力及骨折面张开位移较小,骨折面压力较大.结论 利用双螺钉由前向后固定距骨颈骨折,可以取得较好的生物力学稳定性.%Objective To explore the biomechanical properties of different internal fixations for talar neck fracture through three dimensional finite element ( FE ) analysis and therefore to provide scientific foundation for clinic application. Methods CT scan data were used to develop FE models of the talar neck fracture with different fixations. The different fixations were compared for stress and strain, the fracture surface contact pressure and contact gap were also compared for analysing the biological mechanical stability of different internal fixations. Results The FE models of the talar neck fracture with different fixations were developed. Finite element simulation showed differences between the different fixations with regard to the distributions of stress and contact gap at the fracture surfaces and the von Mises stress in the implant. Anterior to posterior fixation using two screws were shown maximum von Mises stress in the implants, maximum contact press and minimum contact gap in contact surface. Conclusions Anterior to posterior fixation using two screws exhibits fine fixation stability for talar neck fracture.