A comparison between two finite element analysis methods of human tibia via different modeling patterns

TANG Yongtao; WEI Siqi; CHENG Gang; ZHAO Jianhua; CAI Fanfan; OUYANG Hanbin

doi:10.3969/j.issn.1674-666X.2016.01.005

Abstract：Objective To investigate the effects of two modeling approaches on biomechanical response of finite element models of human tibia. Methods A group of data of a volunteer's CT scan was obtained for 3D reconstruction of tibia, and the solid tibial model with cavity structure was then reconstructed by isolating medullary canal and cancellous bone. Material properties in 2 models were assigned via homogeneous and inhomogeneous modulus, identical load case and boundary conditions were applied to simulate the axial compression and torsion loading on the tibia during the mid-stance phase of gait circle simultaneously. Distribution of stress and displacement, stiffness of axial compression and torsion were compared between two models. Results Regarding to the displacement, two models presented similar distribution on the bone surface. Under the two load cases, inhomogeneous model resulted in lower maximum stress and maximum displacement comparing to homogeneous model. Similarly, inhomogeneous group presented higher axial compression stiffness and torsional stiffness than homogeneous group under the same load case. A physiological stress concentration was observed on the distal part of tibia diaphysis in the homogeneous model, which relatively matched the clinical situation. Conclusions Both of the two modeling patterns could be available for finite element analysis of tibia models. However, homogeneous modeling was associated with higher accuracy for prediction of biomechanical response and flexibility in application compared to inhomogeneous modeling.