QCT-based failure analysis of proximal femurs under various loading orientations

Abstract

In this paper, the variations of the failure strength and pattern of human proximal femur with loading orientation were analysed using a novel quantitative computed tomography (QCT)-based linear finite element (FE) method. The QCT images of 4 fresh-frozen femurs were directly converted into voxel-based finite element models for the analyses of the failure loads and patterns. A new geometrical reference system was used for the alignment of the mechanical loads on the femoral head. A new method was used for recognition and assortment of the high-risk elements using a strain energy-based measure. The FE results were validated with the experimental results of the same specimens and the results of similar case studies reported in the literature. The validated models were used for the computational investigation of the failure loads and patterns under 15 different loading conditions. A consistent variation of the failure loads and patterns was found for the 60 different analysed cases. Finally, it was shown that the proposed procedure can be used as a reliable tool for the failure analysis of proximal femurs, e.g. identification of the relevant loading directions for specific failure patterns, or determination of the loading conditions under which the proximal femurs are failure-prone.

Finite element modeling of multiple density materials of bone specimens for biomechanical behavior evaluation

“…Acknowledgements Work presented in this manuscript was supported by the Pontificia Universidad Católica Medicine School and Fig. 12 Effect the number of material definitions has on computational results [42] 2013 Quantitative CT 0.81 Luisier et al [43] 2014 Quantitative CT 0.84 Dall'Ara et al [44] 2012 Quantitative CT 0.87 Koivumäki et al [45] 2012 Standard CT 0.87 Anez-Bustillos et al [46] 2013 Quantitative CT 0.89 Mirzaei et al [47] 2015 Quantitative CT 0.89 Taddei et al [25] 2006 Standard CT 0.91 Helgason et al [2] 2008 Standard CT 0.92 Hambli and Allaoui [48] 2013…”

Prediction of Femoral Strength Based on Bone Density and Biochemical Markers in Elderly Men With Type 2 Diabetes Mellitus

“…For femoral material assignment, apparent density (ρ apparent ) was obtained from the relationship between the density of calibration phantom and the Hounsfiled Unit (HU) value, and ash density (ρ ash ) was calculated using the following equation: ρ ash = 1.22ρ apparent + 0.0526 ( Mirzaei et al, 2015 ). The elastic modulus (E) and yield strength (σ) of the femoral voxel were calculated on the basis of an empirical formula, as shown in Table 1 .…”

The Impact of Coronal Configuration of the Proximal Femur on its Mechanical Properties and the Validation of a New Theoretical Model: Finite Element Analysis and Biomechanical Examination

“…analyzed the change in strength of the proximal femur in different configurations using finite element analysis (FEA). They found that the proximal femur has the greatest strength with a coronal angle of 20° and a sagittal angle of 10° 19 . Levadnyi et al .…”

“…They found that the proximal femur has the greatest strength with a coronal angle of 20 and a sagittal angle of 10 . 19 Levadnyi et al used biomechanics experiment and FEA to explore the change in stiffness and surface strain of the proximal femur under different configurational conditions. It was found that the proximal femur has the greatest compressive stiffness when the coronal angle is about 10 .…”