Finite Element Modeling Of Femur And The Corresponding Biomechanical Analysis

Femur is the longest bone in human body and composed by cancellous bone and cortical bone in anatomy. The main function of femur is as a support in the human movement system. Its head is a component of hip-joint, and its bottom is a part of knee-joint. The damage and the necrosis of femur is a common orthopedic disease. Several limitations exist in the clinical surgery of the traditional prosthetic replacement, e.g., rejection reaction, prosthetic drop, individual variation, etc. At present, finite element modeling has been widely used in the field of biomedical engineering; and the surgery of personalized femoral replacement is a popular research. In this study, a finite element model of femur was remodeled and analyzed using a computer. This model can be used to availably analyze the mechanical properties of femur; and to promote the understanding of the individualized artificial hip-joint.In this study, a fresh porcine femur was obtained to perform the uniaxial compressive test using Instron5544tester. Three strain gages were pasted on three different locations of the specimen. During the experiment, the values of the three points were recorded. Prior to test, computed tomography (CT) was used to determine the geometric morphology of the specimen. The images of CT were input into the software of Mimics10.01to remodel the three dimensional porcine femur and to define the characteristics of materials. Then this geometric model was remodeled into the finite element model using the software of Ansys12.0. The corresponding finite element model was used to simulate the loading situation of the uniaxial compressive test. Compared with the strain values of the above three test points on the specimen, the simulation results fit well to the experimental results. This result shows that the modeling method of this work is available.Then a finite element model of a human femur was remodeled using the same method. This finite element model is coincident with the actual human femur due to its geometry is from the CT images of the same human. Normal standing up was simulated using this model, and the von Mises stresses were obtained under different compressive loadings. The investigation results reveal that the actual human femur can be availably simulated using the finite element model that was established by the relationship between the grey values and the material properties. This model can potentially be applied to simulate the clinical treatment of the femur.