BACKGROUND:With the increasing of aging, the incidence and mortality of osteoporotic hip fracture wil rise. It is of great significance to study the pathogenesis and preventing method. At present, finite element analysis can be used to judge fracture, only for the distribution trend of fracture failure in the starting point or section view, but it cannot completely reflect actual situation of fracture. OBJECTIVE:To build the fracture model of the femoral neck fracture caused by fal ing-induced external force based on the finite element analysis LS-DYNA software, and to evaluate the effect of rupture. METHODS:CT image data of one case of elderly femoral neck fracture were col ected. Using Mimics software, region growth of the contralateral area, cavity fil ing, editing, rebuilding the contralateral proximal femur model were conducted. Data were imported in Hypermesh and LS-DYNA software for meshing, and defining material properties. The failure parameters and interfacial properties were set. The load and force boundary constraints simulating the fal ing were simulated. The model of femoral neck fracture was calculated. Rupture effect was evaluated. RESULTS AND CONCLUSION:(1) The validity of contralateral proximal femur three-dimensional model was verified. Based on the finite element analysis software LS-DYNA, the femoral neck fracture model matched the actual fracture line to a degree of close to 83%. (2) Above results confirmed that based on the finite element analysis, LS-DYNA software can wel simulate the femoral neck fracture, which provides experimental basis to the exploration of femoral neck fracture classification mechanism caused by different fal ing-induced external forces.