新型股骨颈动力交叉钉系统与空心螺钉治疗不同类型股骨颈骨折的有限元分析

Finite Element Analysis of Novel Femoral Neck Dynamic Cross Screw System and Cannulated Screws in the Treatment of Different Types Femoral Neck Fractures

摘要: 目的：采用有限元分析的方法比较新型股骨颈动力交叉钉系统与3枚空心螺钉治疗不同类型股骨颈骨折的生物力学特性。方法：收集1例在院患者髋部CT扫描数据，将该髋部CT数据通过数字医学软件建立股骨三维模型。利用SOLIDWORK2021对股骨模型以30˚，50˚，70˚骨折线角度进行分割来模拟不同Pauwels角度的股骨颈骨折，并按临床上合适尺寸和手术方案植入内固定模型于股骨模型中，分为FNS (新型股骨颈动力交叉钉系统)组与CCS (空心螺钉)组。最后利用ANSYA2021软件进行网格划分，材料赋值，数据计算等步骤后，比较(FNS)与空心螺钉治疗不同类型的股骨颈骨折的生物力学特性。结果：在三种不同骨折角度的情况下FNS组股骨头侧最大应力均小于CS组，即使用FNS固定时，股骨头承担的压力更小；两组模型最大应力均出现在骨折线内侧和下侧。股骨头侧位移FNS组小于空心螺钉组，即使用FNS固定时股骨头侧更不易移位，这对预防髋内翻有重要意义；两组模型最大位移均出现在股骨头顶部。FNS组应力峰值均大于空心螺钉组；而FNS组内固定装置位移峰值均小于CS组，且位移分布更为均匀，而内固定位移直接影响着内固定的切出及股骨颈短缩。结论：FNS治疗不同类型股骨颈骨折生物力学稳定性均优于空心螺钉，是治疗不同类型股骨颈骨折值得优先考虑的内固定方式。

Abstract: Objective: Using finite element analysis to compare the biomechanical properties of novel dynamic cross screw system and cannulated screws in the treatment of different types of femoral neck fractures. Methods: Collected CT scanning data of the healthy hip from an in-hospital patient with a femoral fracture, and established a three-dimensional model of the femur using the digital medicine software. Using SOLIDWORKS 2021, the femur model was segmented at fracture line angles of 30˚, 50˚ and 70˚ to simulate different Pauwels angles of femoral neck fractures. The internal fixation model was implanted into the femoral model according to clinically appropriate dimensions and surgical plans, dividing it into two groups: the FNS (novel dynamic cross screw system for femoral neck) group and the CS (cannulated screws group). Finally, after performing mesh generation, material assignment, and data calculations using ANSYS 2021 software, the biomechanical properties of the FNS group and the CS group in the treatment of different types of femoral neck fractures were compared. Results: In the presence of three different fracture angles, the maximum stress on the femoral head in the FNS group was consistently lower than that in the CS group, indicating that the FNS fixation results in less pressure on the femoral head; The maximum stress in both groups of models occurred on the inner and lower sides of the fracture line; The lateral displacement of the femoral head in the FNS group was less than that in the CS group, indicating that the femoral head is less prone to displacement when using FNS fixation, which have significant importance for preventing hip internal rotation; The maximum displacement in both groups of models occurred at the top of the femoral head. The stress peak values in the FNS group were consistently greater than those in the CS group. However, the peak displacement of the internal fixation device in the FNS group was consistently lower than that in the CS group, and the displacement distribution was more uniform. Additionally, the displacement of the internal fixation directly affects the cutout and shortening of the femoral neck. Conclusion: FNS demonstrates superior biomechanical stability compared to hollow screws in the treatment of various types of femoral neck fractures, making it a preferable option for internal fixation in such cases.