应用三维有限元技术对比分析高海拔地区股骨颈骨折空心螺钉两种构型的稳定性。

获取1例正常股骨颈的CT图像，使用3-matic Research 13.0制备股骨颈骨折模型，分别建立了股骨颈骨折空心螺钉斜三角构型和倒三角构型的有限元模型。对有限元模型分别进行500 N，1 000 N，1 500 N，2 100 N的载荷，观察记录股骨及空心螺钉应力和位移变化情况。

相同载荷下，斜三角构型的各螺钉最大位移、最大VonMises应力均小于倒三角构型的螺钉；斜三角构型股骨头应力集中的范围要小于倒三角构型；两种模型中斜三角构型的股骨整体最大位移均小于倒三角构型；斜三角构型中股骨整体最大Von Mises应力高于倒三角构型。

相同载荷下，斜三角构型更符合股骨颈正常解剖特点，各个螺钉所受的应力分布更为合理，对骨折的固定更为坚强，更能有效避免术后内固定断裂失败、内固定切出等并发症的发生。

To compare the stability of two types of cannulated screws for femoral neck fracture in high altitude area with three-dimensional finite element technique.

CT images of 1 normal femoral neck were obtained and the femoral neck fracture model was prepared by 3-Matic Research 13.0. The finite element models of oblique triangle and inverted triangle of hollow screw were established respectively. The finite element models were loaded at 500 N,1 000 N, 1 500 N and 2 100 N, respectively. The Von Mises peak stress and displacement of cannulated screws and the stress distribution of femoral head were observed and recorded.

Under the same load, the maximum displacement and the maximum VonMises stress of the screw with oblique triangle configuration is smaller than that of the screw with inverted triangle configuration. The stress concentration range of femoral head in oblique triangle configuration was smaller than that in inverted triangle configuration. The overall maximum displacement of femur in oblique triangle configuration was less than that in inverted triangle configuration. The maximum VonMises stress of femur in oblique triangle was higher than that in inverted triangle.

Under the same load, compared with the traditional inverted triangle configuration, the oblique triangle configuration is more consistent with the normal anatomical characteristics of femoral neck, the stress distribution of each screw is more reasonable, the fixation of fracture is stronger, and it can effectively avoid the occurrence of complications such as fracture failure and internal fixation cutting out.