The elastic moduli of human subchondral, trabecular, and cortical bone tissue and the size-dependency of cortical bone modulus

Abstract

Abstract-The elastic moduli of human subchondral. trabecular. and cortical bone tissue from a proximal tibia were experimentally determined using three-point bending tests on a microstructural level. The mean modulus of subchondral specimens was I.ISGPa, and those of trabecular and cortical specimens was 4.59 OPaland 5.44 CPa respectively. Significant differences were found in the modulus values between bone tissues, which may have mainly resulted from the difference in the microstructures ofeach bone tissue rather than in the mineral density. Furthermore, the size-dependency of the modulus was examined using eight different sjza ofcortical specimens(heights h= 100-1000 am). While the modulus values for relatively large specimens (h>5OO~m) remained fairly constant (approximately I5 GPa). the values decreased as the specimens became smaller. A significant correlation was round between the modulus and specimen size. The surface area to volume ratio proved to be a key variable to explain the size-dependency.

A three-scale finite element investigation into the effects of tissue mineralisation and lamellar organisation in human cortical and trabecular bone

“…details regarding stress transfer between constituents in various mineral-collagen arrangements and its effect of macroscopic behaviour), see Figures 3(c) and 4. We propose that the approach developed in this study could be applied to further understand the large discrepancies in reports of mechanical behaviour of bone tissue between different experimental test methods (Runkle and Pugh 1975;Townsend et al 1975;Mente and Lewis 1989;Ryan and Williams 1989;Choi et al 1990;Rho et al 1993;Samelin et al 1996;Rho et al 1997;Rho et al 1998;Rho et al 1999;Zysset et al 1999;Hoffler et al 2000;Ferguson et al 2003;McNamara et al 2006a;Ozcivici et al 2008;McNamara 2011), but also to decipher the impact of changes in tissue composition or structure during disease. From the results presented here, it is clear that a major contributor to this large range of experimentally reported stiffness values is the MVF (Figures 3 and 5).…”

“…Mechanical testing of trabecular and cortical bone tissue has been carried out using 3/4-point bending (Choi et al 1990), buckling (Runkle and Pugh 1975;Townsend et al 1975), cantilever beam tests (Mente and Lewis 1989), micro-tensile testing (Ryan and Williams 1989;Rho et al 1993;Samelin et al 1996;McNamara et al 2005;McNamara et al 2006a), ultrasonic measurement (Rho et al 1993) and nanoindentation (Rho et al 1997;Rho et al 1999;Zysset et al 1999;Hoffler et al 2000;Ferguson et al 2003;Ozcivici et al 2008).…”

“…Reported values for the elastic modulus of trabecular and cortical tissue from these studies have conflicted, with values ranging from 0.75GPa to 30GPa (Runkle and Pugh 1975;Townsend et al 1975;Mente and Lewis 1989;Ryan and Williams 1989;Choi et al 1990;Rho et al 1993;Samelin et al 1996;Rho et al 1997;Rho et al 1998;Rho et al 1999;Zysset et al 1999;Hoffler et al 2000;Ferguson et al 2003;McNamara et al 2006a;Ozcivici et al 2008;McNamara 2011). There is much contention regarding whether cortical and trabecular bone are fundamentally the same tissue, and that it is their tissue organisation that distinguishes their mechanical behaviour, or whether the tissue composition and mechanical properties are different between the two bone types.…”

Application of homogenization theory to the study of trabecular bone mechanics

“…Initial experimental evaluation of microstructural models suggests that different microstructural models may be needed for different metaphyseal regions, as well as for different volume fractions of trabecular bone within a metaphyseal region. Additionally, the possibility of a trabecular tissue modulus size effect (Choi et al, 1990) needs to be examined in future microstructural models of trabecular bone.…”

“…Experimental data were taken from the study of Ciarelli et al (1986) and consisted of three orthogonal moduli from tests on 6-8 mm bone cubes. The tissue was assumed to be isotropic with a modulus of 5 GPa (Choi et al, 1990;Kuhn et al, 1989;Mente and Lewis, 1989) and a Poisson's ratio of 0.3 in each analysis. In addition, the average trabecular morphology and anisotropy of the specimens were measured using a special three-dimensional micro CT scanner Goulet et al, 1989).…”