小夹板治疗桡骨远端关节内骨折的有限元分析

目的 探讨小夹板固定治疗桡骨远端C型骨折的适用范围。方法 根据健康男性志愿者右前臂CT扫描数据，建立正常桡骨远端三维模型。依据AO分型，在正常模型基础上人为划分骨折线，建立9种C型骨折前臂高阶四面体网格模型。在ANSYS 15.0软件中对9种骨折模型进行有限元分析，得出相应的应力，然后以等值线图的方式生成应力分布云图。结果 由于腕部软组织薄，骨折块较多，夹板固定后，在100 N最大生理轴向载荷作用下，腕部的应力与其他部位比较明显偏大，压应力主要集中在桡腕关节处。C2.2、C2.3、C3.2、C3.3型骨折由于粉碎性骨折造成的骨折块过多过小，小夹板的骨折块固定效果较差；而对于C1.1、C1.2、C1.3、C2.1及C3.1型骨折，小夹板的固定效果较好。结论 通过对小夹板治疗桡骨远端C型骨折进行相关有限元研究，初步确定了其适用范围，可为临床工作提供一些参考。
Objective To explore the application scope of small splint in the treatment of type-C distal radius fractures. Methods According to CT scan data from the right forearm of a healthy male volunteer, the three-dimensional model of normal distal radius was established. According to AO classification, the fracture line based on normal model was divided to establish nine kinds of high-order tetrahedral mesh models of the upper forearm with C-type fracture. Finite element analysis on nine kinds of fracture models was conducted in ANSYS 15.0 software to obtain the corresponding stress values, and then the stress distribution contours were generated. Results As soft tissues of the wrist were thin with more fracture blocks, after the splint was fixed, the stress on the wrist under 100 N maximum physiological axial load was significantly larger compared with that on the other parts, and the compressive stress was mainly concentrated on the wrist joint. The fixed effect of C2.2, C2.3, C3.2, C3.3-type fracture by small splint was relatively poor, as such comminuted fracture would cause too many and too small fracture blocks, while the fixed effect of C1.1, C1.2, C1.3, C2.1 and C3.1-type fracture was better. Conclusions Through the related finite element study on the treatment of C-type fracture distal radius with small splint, the application scope of small splint was preliminarily determined, which could provide some reference for clinical work.