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目的:通过有限元分析比较菱形构型空心钉、动力髋螺钉（DHS）结合防旋螺钉及传统倒三角形构型空心钉固定Pauwels Ⅲ型股骨颈骨折的生物力学性能。方法:选取1名65岁健康男性志愿者，获取其右股骨颈近端CT数据，以及空心钉、DHS数据，通过Mimics 14.0软件构建Pauwels Ⅲ型股骨颈骨折模型和3种内固定模型。实验分3组：菱形组采用4枚菱形构型空心钉固定，倒三角形组采用倒三角形构型空心钉固定，DHS组采用DHS结合防旋螺钉固定。将上述模型导入Ansys12.1有限元分析软件中，模拟人体直立情况下内固定物的应力分布及骨折处的位移。结果:菱形组、倒三角形组、DHS组模型股骨颈内螺钉应力峰值分别为26.95、39.48、34.57 MPa，DHS组模型整体应力峰值集中于股骨干侧方钢板的远端螺钉处，为50.36 MPa；骨折断端应力峰值分别为9.55、10.07、20.10 MPa；骨折断端位移峰值分别为0.64、0.65、0.67 mm。结论:与其他2种内固定方式相比，4枚菱形构型的空心钉固定Pauwels Ⅲ型股骨颈骨折具有更优的抗剪切力及应力分散作用，且能够在提供有效滑动加压作用的同时减少术后股骨颈短缩。“,”Objective:To compare the biomechanical properties of four-screw diamond internal fixation, traditional three-screw internal fixation and internal fixation with dynamic hip screw plus one anti-rotation screw for femoral neck fracture of Pauwels type Ⅲ.Methods:The CT data of the right femoral neck of a 65-year-old healthy male volunteer and the data of cannulated screw and dynamic hip screw (DHS) provided by Synthes medical-device company were used to create models of femoral neck fracture of Pauwels type Ⅲ and models of 3 modes of internal fixation via Mimics 14.0 software: four-screw diamond internal fixation (group A), three-screw inverted triangle internal fixation (group B) and internal fixation with DHS plus one anti-rotation screw (group C). The 3 kinds of models were input into the finite element analysis software Ansys12.1 to stimulate the fracture site displacements and stress distributions on internal fixation when a human body was in upright position.Results:For groups A, B and C, the peak stresses on the femoral neck screws were 26.95 MPa, 39.48 MPa and 34.57 MPa. The overall stress peak in group C was 50.36 Mpa, concentrated at the distal screw on the femoral shaft plate. For groups A, B and C, the peak stresses at fracture site were 9.55 MPa, 10.07 MPa and 20.10 MPa, and the peak displacements 0.64 mm, 0.65 mm and 0.67 mm.Conclusions:Compared with the other 2 modes of internal fixation, diamond fixation of femoral neck fracture of Pauwels type Ⅲ with 4 cannulated screws may result in better anti-shearing force and dispersion of stresses. In addition, it can provide effective sliding compression and reduce postoperative shortening of the femoral neck.