Biomechanical comparison using finite element analysis of different screw configurations in the fixation of femoral neck fractures

摘要

In this research, biomechanical behaviors of five different configurations ofscrews used for stabilization of femoral neck fracture under axial loadinghave been examined, and which configuration is best has been investigated.A point cloud was obtained after scanning the human femoral model with a threedimensional (3-D) scanner, and this point cloud was converted to a 3-Dfemoral model by Geomagic Studio software. Femoral neck fracture was modeledby SolidWorks software for five different configurations: dual parallel, tripleparallel, triangle, inverted triangle and square, and computer-aidednumerical analysis of different configurations were carried out byANSYS Workbench finite element analysis (FEA) software. For eachconfiguration, mesh process, loading status (axial), boundary conditions andmaterial model were applied in finite element analysis software. Von Mises stress values in the upper and lowerproximity of the femur and screws were calculated. According to FEA results, it wasparticularly advantageous to use the fixation type of triangleconfiguration. The lowest values are found as 223.32 MPa at the lower, 63.34 MPaat the upper proximity and 493.24 MPa at the screws in triangleconfiguration. This showed that this configuration creates minimum stress atthe upper and lower proximity of the fracture line. Clinically, we believethat the lowest stress values which are created by triangle configurationencompass the most advantageous method. In clinical practices, it is believed that usingmore than three screws does not provide any benefit. Furthermore, the higheststresses are as follows: at upper proximity 394.79 MPa intriple parallel configuration, for lower proximity 651.2 MPa in squareconfiguration and for screw 2459 MPa in inverted triangle.