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目的:探讨“轴心加压+侧方支撑”理念下新型空心螺钉固定Pauwels Ⅱ型股骨颈骨折的生物力学性能。方法:将10根Sawbones仿真股骨标本首先制作成Pauwels角为50°的Ⅱ型股骨颈骨折模型，编号后随机分为两组（n n=5）：实验组与对照组。实验组标本采用“轴心加压+侧方支撑”理念下新型空心螺钉组合固定：轴心螺钉直径为8.5 mm，侧方螺钉直径为6.5 mm；对照组标本采用传统倒三角形空心螺钉平行加压固定：3枚螺钉直径均为7.3 mm。将标本置于生物力学试验机上，依次测试静态轴向刚度、5 000个循环60~600 N载荷下位移、极限载荷和极限刚度参数，比较两组的差异。n 结果:实验组标本的静态轴向刚度[（1 492.00 ± 87.86）N/mm]显著高于对照组标本[（1 200.22 ± 228.06）N/mm]，差异有统计学意义（n P0.05），但实验组呈现出较低趋势。实验组标本的极限载荷和极限刚度分别为（4 292.61 ± 804.29）N、（1 623.55 ± 180.94）N/mm，对照组分别为（4 383.64 ± 1 423.24）N、（1 433.77 ± 289.93）N/mm，两组比较差异均无统计学意义（n P> 0.05）。n 结论:“轴心加压+侧方支撑”理念下新型空心螺钉固定Pauwels Ⅱ型股骨颈骨折较传统倒三角形空心螺钉平行加压固定的生物力学性能更优。“,”Objective:To investigate the biomechanical properties of cannulated screws fixation in a configuration of “axial compression and lateral buttress” in the treatment of Pauwels type Ⅱ femoral neck fractures.Methods:Ten specimens of Sawbones artificial femur were first made into models of type Ⅱ femoral neck fracture with a Pauwells angle of 50° and then randomized into 2 equal groups (n n=5). The specimens in the experimental group were subjected to fixation with cannulated screws in a configuration of “axial compression and lateral buttress” in which the axial screw was 8.5 mm in diameter and the lateral screw 6.5 mm in diameter. The specimens in the control group were subjected to conventional fixation with cannulated screws in a configuration of “inverted triangle and parallel compression” in which the 3 screws was 7.3 mm in diameter. Finally, the specimens were placed onto a biomechanical testing machine to determine the parameters of static axial stiffness, displacement under 60 to 600 N load for 5,000 cycles, ultimate load and ultimate stiffness in turn. The 2 groups were compared to find out their differences.n Results:The static axial stiffness was (1,492.00 ± 87.86) N/mm, significantly higher than that in the control group [(1,200.22 ± 228.06) N/mm] (n P0.05), but the experimental group showed a lower trend. The ultimate load and ultimate stiffness were (4,292.61 ± 804.29) N and (1,623.55 ± 180.94) N/mm in the experimental group and (4,383.64 ± 1,423.24) N and (1,433.77 ± 289.93) N/mm in the control group, showing no significant difference between the 2 groups (n P>0.05).n Conclusion:In the treatment of Pauwels type Ⅱ femoral neck fractures, fixation with cannulated screws in a configuration of “axial compression and lateral buttress” may exhibit better biomechanical properties than that in a conventional configuration of “inverted triangle” .