MicroCT-based finite element models as a tool for virtual testing of cortical bone.

The aim of this study was to assess a virtual biomechanics testing approach purely based on microcomputed tomography (microCT or µCT) data, providing non-invasive methods for determining the stiffness and strength of cortical bone. Mouse femurs were µCT scanned prior to three-point-bend tests. Then microCT-based finite element models were generated with spatial variation in bone elastoplastic properties and subject-specific femur geometries. Empirical relationships of density versus Young's moduli and yield stress were used in assigning elastoplastic properties to each voxel. The microCT-based finite element modeling (µFEM) results were employed to investigate the model's accuracy through comparison with experimental tests. The correspondence of elastic stiffness and strength from the µFE analyses and tests was good. The interpretation of the derived data showed a 6.1%, 1.4%, 1.5%, and 1.6% difference between the experimental test result and µFEM output on global stiffness, nominal Young's modulus, nominal yield stress, and yield force, respectively. We conclude that virtual testing outputs could be used to predict global elastic-plastic properties and may reduce the cost, time, and number of test specimens in performing physical experiments.

[1]  M. Panjabi,et al.  Effects of freezing and freeze‐drying on the biomechanical properties of rat bone , 1984, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[2]  D. Carnelli,et al.  Nanoindentation testing and finite element simulations of cortical bone allowing for anisotropic elastic and inelastic mechanical response. , 2011, Journal of biomechanics.

[3]  Ralph Müller,et al.  Tissue modulus calculated from beam theory is biased by bone size and geometry: implications for the use of three-point bending tests to determine bone tissue modulus. , 2008, Bone.

[4]  Yongxin Zhou,et al.  Comparison of isotropic and orthotropic material property assignments on femoral finite element models under two loading conditions. , 2006, Medical engineering & physics.

[5]  F. Eckstein,et al.  Estimation of distal radius failure load with micro-finite element analysis models based on three-dimensional peripheral quantitative computed tomography images. , 2002, Bone.

[6]  M. V. D. van der Meulen,et al.  Finite element models predict cancellous apparent modulus when tissue modulus is scaled from specimen CT-attenuation. , 2004, Journal of biomechanics.

[7]  Alejandro F. Frangi,et al.  Statistical estimation of femur micro-architecture using optimal shape and density predictors. , 2015, Journal of biomechanics.

[8]  P. Rüegsegger,et al.  Morphometric analysis of noninvasively assessed bone biopsies: comparison of high-resolution computed tomography and histologic sections. , 1996, Bone.

[9]  K. Radermacher,et al.  Critical evaluation of known bone material properties to realize anisotropic FE-simulation of the proximal femur. , 2000, Journal of biomechanics.

[10]  G. Beaupré,et al.  Improving the Estimate of the Effective Elastic Modulus Derived from Three-Point Bending Tests of Long Bones , 2014, Annals of Biomedical Engineering.

[11]  W. Hayes,et al.  Mechanical properties of trabecular bone from the proximal femur: a quantitative CT study. , 1990, Journal of computer assisted tomography.

[12]  Marco Viceconti,et al.  Subject-specific finite element models can accurately predict strain levels in long bones. , 2007, Journal of biomechanics.

[13]  B. van Rietbergen,et al.  A survey of micro-finite element analysis for clinical assessment of bone strength: the first decade. , 2015, Journal of biomechanics.

[14]  W C Hayes,et al.  Mechanical properties of metaphyseal bone in the proximal femur. , 1991, Journal of biomechanics.

[15]  P. Zysset,et al.  Mineral heterogeneity has a minor influence on the apparent elastic properties of human cancellous bone: a SRμCT-based finite element study , 2012, Computer methods in biomechanics and biomedical engineering.

[16]  Ralph Müller,et al.  Improved Fracture Risk Assessment Based on Nonlinear Micro‐Finite Element Simulations From HRpQCT Images at the Distal Radius , 2013, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[17]  T. Keaveny,et al.  Trabecular bone modulus-density relationships depend on anatomic site. , 2003, Journal of biomechanics.

[18]  G. Niebur,et al.  High-resolution finite element models with tissue strength asymmetry accurately predict failure of trabecular bone. , 2000, Journal of biomechanics.

[19]  M. Viceconti,et al.  Mathematical relationships between bone density and mechanical properties: a literature review. , 2008, Clinical biomechanics.

[20]  Panayiotis Papadopoulos,et al.  The modified super-ellipsoid yield criterion for human trabecular bone. , 2004, Journal of biomechanical engineering.

[21]  Bjørn Skallerud,et al.  Subject specific finite element analysis of stress shielding around a cementless femoral stem. , 2009, Clinical biomechanics.

[22]  I. Stockley,et al.  BIOMECHANICAL PROPERTIES OF CORTICAL ALLOGRAFT BONE USING A NEW METHOD OF BONE STRENGTH MEASUREMENT , 1996 .

[23]  Philippe Zysset A constitutive law for trabecular bone , 1994 .

[24]  Kent D. Butz,et al.  Characterization of cancellous and cortical bone strain in the in vivo mouse tibial loading model using microCT-based finite element analysis. , 2014, Bone.

[25]  P. Zysset,et al.  Experimental validation of a nonlinear μFE model based on cohesive‐frictional plasticity for trabecular bone , 2016, International journal for numerical methods in biomedical engineering.

[26]  B. Snyder,et al.  Compressive axial mechanical properties of rat bone as functions of bone volume fraction, apparent density and micro-ct based mineral density. , 2010, Journal of biomechanics.

[27]  L. Mosekilde,et al.  Cortical bone mass, composition, and mechanical properties in female rats in relation to age, long-term ovariectomy, and estrogen substitution , 2004, Calcified Tissue International.

[28]  S. Goldstein,et al.  Elastic modulus and hardness of cortical and trabecular bone lamellae measured by nanoindentation in the human femur. , 1999, Journal of biomechanics.

[29]  R. Huiskes,et al.  A new method to determine trabecular bone elastic properties and loading using micromechanical finite-element models. , 1995, Journal of biomechanics.

[30]  G. Pharr,et al.  Elastic properties of human cortical and trabecular lamellar bone measured by nanoindentation. , 1997, Biomaterials.

[31]  S. Majumdar,et al.  High-resolution MRI and micro-FE for the evaluation of changes in bone mechanical properties during longitudinal clinical trials: application to calcaneal bone in postmenopausal women after one year of idoxifene treatment. , 2002, Clinical biomechanics.

[32]  G. Beaupré,et al.  The influence of bone volume fraction and ash fraction on bone strength and modulus. , 2001, Bone.

[33]  Hyatt Gw,et al.  Ultrasonics and physical properties of healing bone. , 1972 .

[34]  A. M. Parfitt,et al.  Age-related structural changes in trabecular and cortical bone: Cellular mechanisms and biomechanical consequences , 2006, Calcified Tissue International.

[35]  J. F. V. Vincent,et al.  Young’s moduli and shear moduli in cortical bone , 1996, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[36]  Stuart J Warden,et al.  A comparison of mechanical properties derived from multiple skeletal sites in mice. , 2005, Journal of biomechanics.

[37]  C. Simmons,et al.  Trabecular bone morphology from micro‐magnetic resonance imaging , 1996, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[38]  P. Zysset,et al.  In situ micropillar compression reveals superior strength and ductility but an absence of damage in lamellar bone. , 2014, Nature materials.

[39]  Haisheng Yang,et al.  Some factors that affect the comparison between isotropic and orthotropic inhomogeneous finite element material models of femur. , 2010, Medical engineering & physics.

[40]  R. Vanderby,et al.  Ultrasonic wave velocity measurement in small polymeric and cortical bone specimens. , 1997, Journal of biomechanical engineering.

[41]  J. Reseland,et al.  Skeletal effects of a gastrin receptor antagonist in H+/K+ATPase beta subunit KO mice. , 2016, The Journal of endocrinology.

[42]  Richard Weinkamer,et al.  Nature’s hierarchical materials , 2007 .