Influence of a gradient of material properties on ultrasonic wave propagation in cortical bone: application to axial transmission.

The aim of this work is to evaluate the effect of a spatial gradient of material properties (mass density and stiffness coefficients) of cortical bone on its ultrasonic response obtained with an axial transmission device. Therefore, a two-dimensional finite element time-domain method is derived to model transient wave propagation in a three-layer medium composed of an inhomogeneous transverse isotropic solid layer sandwiched between two acoustic fluid layers and excited by an acoustic linear source located in one fluid layer, delivering broadband ultrasonic pulses. The model couples the acoustic propagation in both fluid media with the elastodynamic response of the solid layer. A constant spatial gradient of material properties is considered for two values of bone thicknesses corresponding to relatively thick and thin bone widths. For a thin bone (0.6 mm) compared to wavelength (around 4 mm at 1 MHz), the results are in good agreement with a S(0) Lamb wave assuming a homogeneous material with spatially averaged material properties. For a thick bone (4 mm), the results are in agreement with the propagation of a lateral wave and allow the derivation of an equivalent contributing depth in the case of a transverse isotropic inhomogeneous solid layer.

[1]  F. Patat,et al.  Bidirectional axial transmission can improve accuracy and precision of ultrasonic velocity measurement in cortical bone: a validation on test materials , 2004, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[2]  H. Rico The Therapy of Osteoporosis and the Importance of Cortical Bone , 1997, Calcified Tissue International.

[3]  Salah Naili,et al.  A theoretical analysis in the time-domain of wave reflection on a bone plate , 2006 .

[4]  D. Chimenti,et al.  Free Wave Propagation in Plates of General Anisotropic Media , 1989 .

[5]  John G Clement,et al.  Regional variation of intracortical porosity in the midshaft of the human femur: age and sex differences , 2005, Journal of anatomy.

[6]  S. Cummings,et al.  Which fractures are associated with low appendicular bone mass in elderly women? The Study of Osteoporotic Fractures Research Group. , 1992, Annals of internal medicine.

[7]  Robin O Cleveland,et al.  Derivation of elastic stiffness from site-matched mineral density and acoustic impedance maps , 2006, Physics in medicine and biology.

[8]  Laurence J. Jacobs,et al.  Modeling elastic wave propagation in waveguides with the finite element method , 1999 .

[9]  Dimitrios I Fotiadis,et al.  Three-dimensional finite element modeling of guided ultrasound wave propagation in intact and healing long bones. , 2007, The Journal of the Acoustical Society of America.

[10]  R. Heaney,et al.  Cortical ultrasound velocity as an indicator of bone status , 2005, Osteoporosis International.

[11]  Maryline Talmant,et al.  Effect of porosity on effective diagonal stiffness coefficients (cii) and elastic anisotropy of cortical bone at 1 MHz: a finite-difference time domain study. , 2007, The Journal of the Acoustical Society of America.

[12]  M. Grynpas,et al.  Age and disease-related changes in the mineral of bone , 2005, Calcified Tissue International.

[13]  C. Njeh,et al.  Does Combining the Results from Multiple Bone Sites Measured by a New Quantitative Ultrasound Device Improve Discrimination of Hip Fracture? , 1999, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[14]  C. Thomas,et al.  Relation between age, femoral neck cortical stability, and hip fracture risk , 2005, The Lancet.

[15]  A. Burstein,et al.  The Mechanical Properties of Cortical Bone , 1974 .

[16]  J. Rho An ultrasonic method for measuring the elastic properties of human tibial cortical and cancellous bone. , 1996, Ultrasonics.

[17]  M. Sasso,et al.  Dependence of ultrasonic attenuation on bone mass and microstructure in bovine cortical bone. , 2008, Journal of biomechanics.

[18]  J. Compston,et al.  A prospective study of discordance in diagnosis of osteoporosis using spine and proximal femur bone densitometry , 2003, Osteoporosis International.

[19]  C. Soize,et al.  Modélisation probabiliste d'une expérience ultrasonore : calcul de la dispersion sur les mesures de célérité , 2005 .

[20]  D Aubry,et al.  Effect of microstructure on the mechanical properties of Haversian cortical bone. , 2006, Bone.

[21]  Christian Soize,et al.  Elastoacoustic model with uncertain mechanical properties for ultrasonic wave velocity prediction: application to cortical bone evaluation. , 2006, The Journal of the Acoustical Society of America.

[22]  E Vicaut,et al.  Distribution of Intracortical Porosity in Human Midfemoral Cortex by Age and Gender , 2001, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[23]  E. Bossy,et al.  Effect of bone cortical thickness on velocity measurements using ultrasonic axial transmission: a 2D simulation study. , 2002, The Journal of the Acoustical Society of America.

[24]  Eugène Dieulesaint,et al.  Elastic Waves in Solids II , 2000 .

[25]  Maryline Talmant,et al.  Three-dimensional simulations of ultrasonic axial transmission velocity measurement on cortical bone models. , 2004, The Journal of the Acoustical Society of America.

[26]  R. Rizzoli,et al.  Bone strength and its determinants , 2003, Osteoporosis International.

[27]  C. Turner Biomechanics of Bone: Determinants of Skeletal Fragility and Bone Quality , 2002, Osteoporosis International.

[28]  H K Genant,et al.  A new method for quantitative ultrasound measurements at multiple skeletal sites: first results of precision and fracture discrimination. , 2000, Journal of clinical densitometry : the official journal of the International Society for Clinical Densitometry.

[29]  R. Lakes,et al.  Ultrasonic wave propagation and attenuation in wet bone. , 1986, Journal of biomedical engineering.

[30]  X Edward Guo,et al.  The dependence of transversely isotropic elasticity of human femoral cortical bone on porosity. , 2004, Journal of biomechanics.

[31]  Françoise Peyrin,et al.  Variation of Ultrasonic Parameters With Microstructure and Material Properties of Trabecular Bone: A 3D Model Simulation , 2007, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[32]  Dale E. Chimenti,et al.  Ultrasonic Wave Reflection From Liquid-Coupled Orthotropic Plates With Application to Fibrous Composites , 1988 .

[33]  Christian Hellmich,et al.  'Universal' microstructural patterns in cortical and trabecular, extracellular and extravascular bone materials: micromechanics-based prediction of anisotropic elasticity. , 2007, Journal of theoretical biology.

[34]  Françoise Peyrin,et al.  Bone microstructure and elastic tissue properties are reflected in QUS axial transmission measurements. , 2005, Ultrasound in medicine & biology.

[35]  Christian Soize,et al.  A time-domain method to solve transient elastic wave propagation in a multilayer medium with a hybrid spectral-finite element space approximation , 2008 .

[36]  M. Sasso,et al.  Frequency dependence of ultrasonic attenuation in bovine cortical bone: an in vitro study. , 2007, Ultrasound in medicine & biology.

[37]  S. Cummings,et al.  Which Fractures Are Associated with Low Appendicular Bone Mass in Elderly Women , 1991 .

[38]  Françoise Peyrin,et al.  An In Vitro Study of the Ultrasonic Axial Transmission Technique at the Radius: 1‐MHz Velocity Measurements Are Sensitive to Both Mineralization and Intracortical Porosity , 2004, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.