载距突螺钉内固定治疗SandersⅡ型跟骨骨折的生物力学研究  

Biomechanical study of the sustentaculum tali screw placement for the treatment of Sanders type H calcaneal fracture

作　　者：郭宗慧[1] 庞清江[1] 刘江涛[1] 余霄[1] 杨长春[1] 郑兴国[1] 

机构地区：[1]宁波市第二医院骨科中心,315000

出　　处：《中华骨科杂志》2013年第4期331-335,共5页Chinese Journal of Orthopaedics

基　　金：宁波市社会发展项目（2011C50063）

摘　　要：目的探讨载距突螺钉内固定在SandersⅡ型跟骨骨折治疗中的作用及必要性。方法将跟骨CT扫描后的Dicom数据输入Mimics12．0软件及Ansys13．0软件中构建跟骨三维有限元数字模型。而后，将此模型导入Solidworks2010软件中，根据Sanders分型切割跟骨，建立SandersⅡ型跟骨骨折模型。将AO跟骨钢板及螺钉的几何参数输入Solidworks2010软件中，在跟骨模型的基础上建立两种内固定模拟，一种为钢板放于跟骨外侧面，在钢板后关节面下方2枚螺钉孔、钢板后方2枚螺钉孔、钢板下方1枚螺钉孔、钢板前方2枚螺钉孔分别垂直跟骨打入松质骨螺钉；另一种为在前一种固定方式的基础上再在钢板后关节面最下方螺钉孔向载距突打入1枚皮质骨螺钉。在相同条件下分别对两种内固定模型加载，行非线性有限元分析，分别计算两种内固定模型的应力分布情况。结果在相同条件的加载下两种内固定跟骨模型的最大主应力均集中于载距突皮质骨，载距突螺钉内固定模型在骨缝间位移值、跟骨最大主应力值、钢板螺钉内固定系统的最大主应力值方面均较无载距突螺钉内固定模型小，且应力更分散。结论载距突螺钉内固定治疗跟骨骨折符合生物力学稳定性，可很好地用于临床。Objective To explore the necessity and function of the sustentaculum tali screw place- ment for the treatment of Sanders type Ⅱ calcaneal fracture. Methods The data of Dicom that CT scan with bone was input into Mimics 12.0 software and Ansys 13.0 software for construction of calcaneus three-dimen- sional finite element model. Then, this model was imported into Solidworks 2010 software. Type Ⅱ calcaneal fracture model was established according to Sanders type cutting of calcaneus. Geometric parameters of AO calcaneal plate and screws were imported to the Solidworks 2010 software. Two internal fixation simulations were established based on the calcaneal model. In one model, the steel was placed on the outside with bone and the cancellous＂ bone screws were infiltrated respectively into the vertical bone since two screw holes which under the articular surface behind the steel plate, two screw holes which rear of the steel plate, a screw hole of the below calcaneus, two screw holes which in front of steel plate. In another model, a cortical bone screw was infiltrated into the sustentaculum tali through the bottom screw hole of articular surface of the steel plate. The two internal fixation models were loaded under the same condition, and non linear finite element analysis was carried out. The stress distribution in the two internal fixation models was calculated respectively. Results The maximum principal stress focused on the cortical bone of sustentaculum tali in both of the models under the same condition of loading. Bone joint displacement, maximum principal stress of calcaneal and internal fixation system in the model with sustentaculum screw fixation were smaller than that in the model without sustentaculum screw fixation. The stress in the model with sustentaculum screw fixation was more dispersed. Conclusion The placement of sustentaculum tali screw is essential for fixation of type II calcaneal fracture to achieve the biomechanical stability and can be used in clinical.

关 键 词：跟骨 骨折 生物力学 有限元分析 

分 类 号：R687.3[医药卫生—骨科学]