Skip to main content
. Author manuscript; available in PMC: 2020 Oct 1.
Published in final edited form as: Bone. 2019 May 2;127:91–103. doi: 10.1016/j.bone.2019.04.019

Table 4:

Whole-bone mechanical and material properties from three-point bending and FEA

6 mo 18 mo 24 mo
Sham
n = 5
CKD
n = 7
Sham
n = 8
CKD
n = 9
Sham
n = 8
CKD
n = 8
Stiffness (N/mm) 99.2 ± 5.11 88.5 ± 4.68 91.5 ± 6.03 64.4 ± 6.39 83.2 ± 6.93 62.7 ± 6.23
Age: p = 0.009
CKD: p < 0.001
Age × CKD: NS

Modulus (GPa) 7.44 ± 0.237 7.22 ± 0.266 5.53 ± 0.307 4.95 ± 0.360 3.92 ± 0.240 3.69 ± 0.186
Age: p < 0.001
CKD: NS
Age × CKD: NS

Yield Stress (MPa) 132 ± 10.7 127 ± 4.74 82.2 ± 6.51 76.0 ± 10.2 65.9 ± 7.46 66.1 ± 4.74
Age: p < 0.001
CKD: NS
Age × CKD: NS

Maximum Stress (MPa) 163 ± 3.55 154 ± 3.88 110 ± 3.62 112 ± 6.53 97.4 ± 5.99 90.5 ± 4.81
Age: p < 0.001
CKD: NS
Age × CKD: NS

Work to Fracture (mJ) 6.40 ± 1.48 4.47 ± 0.735 8.51 ± 1.25 3.87 ± 1.22 5.11 ± 1.89 4.53 ± 1.03
Age: p > 0.05
CKD: p = 0.041
Age × CKD: NS

Toughness (MJ/m3) 7.54 ± 1.86 4.87 ± 0.582 8.43 ± 1.78 4.39 ± 1.51* 3.03 ± 0.982 5.86 ± 1.10
Age: NS
CKD: NS p = 0.022 p = 0.046
Age × CKD: p = 0.011 −47.9% +93.9%

Post-Yield Displacement (mm) 0.342 ± 0.0954 0.195 ± 0.0216 0.947 ± 0.227 0.535 ± 0.226 0.250 ± 0.0672 0.481 ± 0.117
Age: NS
CKD: NS
Age × CKD: NS

FEA Stiffness (N/mm) 9680 ± 305 8750 ± 595 7780 ± 254 6440 ± 289 7840 ± 503 6550 ± 454
Age: p < 0.001
CKD: p < 0.001
Age × CKD: NS

Data are presented as mean +/− standard error of the mean. P-values for main effects of age and CKD as well as their interaction are reported in the left column. Post-hoc testing was performed for measures with a significant interaction between age and CKD.

*

Indicates significant difference between Sham and CKD at the same age (p < 0.017, Bonferroni-adjusted critical α), while percent differences between Sham and CKD are noted when p < 0.05.