TY - JOUR
T1 - Anisotropic properties of human tibial cortical bone as measured by nanoindentation
AU - Fan, Z.
AU - Swadener, J.G.
AU - Rho, J.Y.
AU - Roy, M.E.
AU - Pharr, G.M.
N1 - MEDLINE® is the source for the MeSH terms of this document.
PY - 2002/7
Y1 - 2002/7
N2 - The purpose of this study was to investigate the
effects of elastic anisotropy on nanoindentation measurements in human
tibial cortical bone. Nanoindentation was conducted in 12 different
directions in three principal planes for both osteonic and interstitial
lamellae. The experimental indentation modulus was found to vary with
indentation direction and showed obvious anisotropy (oneway analysis of
variance test, P < 0.0001). Because experimental indentation
modulus in a specific direction is determined by all of the elastic
constants of cortical bone, a complex theoretical model is required to
analyze the experimental results. A recently developed analysis of
indentation for the properties of anisotropic materials was used to
quantitatively predict indentation modulus by using the stiffness matrix
of human tibial cortical bone, which was obtained from previous
ultrasound studies. After allowing for the effects of specimen
preparation (dehydrated specimens in nanoindentation tests vs. moist
specimens in ultrasound tests) and the structural properties of bone
(different microcomponents with different mechanical properties), there
were no statistically significant differences between the corrected
experimental indentation modulus (Mexp) values and corresponding predicted indentation modulus (Mpre) values (two-tailed unpaired t-test, P < 0.5). The variation of Mpre values was found to exhibit the same trends as the corrected Mexp
data. These results show that the effects of anisotropy on
nanoindentation measurements can be quantitatively evaluated.
AB - The purpose of this study was to investigate the
effects of elastic anisotropy on nanoindentation measurements in human
tibial cortical bone. Nanoindentation was conducted in 12 different
directions in three principal planes for both osteonic and interstitial
lamellae. The experimental indentation modulus was found to vary with
indentation direction and showed obvious anisotropy (oneway analysis of
variance test, P < 0.0001). Because experimental indentation
modulus in a specific direction is determined by all of the elastic
constants of cortical bone, a complex theoretical model is required to
analyze the experimental results. A recently developed analysis of
indentation for the properties of anisotropic materials was used to
quantitatively predict indentation modulus by using the stiffness matrix
of human tibial cortical bone, which was obtained from previous
ultrasound studies. After allowing for the effects of specimen
preparation (dehydrated specimens in nanoindentation tests vs. moist
specimens in ultrasound tests) and the structural properties of bone
(different microcomponents with different mechanical properties), there
were no statistically significant differences between the corrected
experimental indentation modulus (Mexp) values and corresponding predicted indentation modulus (Mpre) values (two-tailed unpaired t-test, P < 0.5). The variation of Mpre values was found to exhibit the same trends as the corrected Mexp
data. These results show that the effects of anisotropy on
nanoindentation measurements can be quantitatively evaluated.
KW - anisotropy
KW - nanoindentation
KW - modulus
KW - bone
UR - http://www.scopus.com/inward/record.url?scp=0036316516&partnerID=8YFLogxK
UR - http://onlinelibrary.wiley.com/doi/10.1016/S0736-0266%2801%2900186-3/abstract
U2 - 10.1016/S0736-0266(01)00186-3
DO - 10.1016/S0736-0266(01)00186-3
M3 - Article
AN - SCOPUS:0036316516
SN - 0736-0266
VL - 20
SP - 806
EP - 810
JO - Journal of Orthopaedic Research
JF - Journal of Orthopaedic Research
IS - 4
ER -