Table 1.
Selected properties of bone, as determined by μCT and three-point bending, for males (top) and females (bottom), comparing control (IR flox) and OIRKO mice.
| Property (male) | Units | IR flox (n = 6) | OIRKO (n = 9) | P-value |
|---|---|---|---|---|
| Metaphysis (trabecular bone) | ||||
| BV/TV | % | 11.71 ± 0.94 | 8.95 ± 2.04 | 0.009 |
| Tb.N | mm−1 | 5.15 ± 0.33 | 4.95 ± 0.61 | 0.47 |
| Tb.Th | mm | 0.0392 ± 0.002 | 0.0344 ± 0.002 | <0.001 |
| Tb.Sp | mm | 0.195 ± 0.013 | 0.206 ± 0.028 | 0.38 |
| SMIa | — | 2.33 ± 0.08 | 2.61 ± 0.20 | 0.006 |
| Tb.TMD | mgHA/cm3 | 901 ± 8 | 888 ± 17 | 0.10 |
|
| ||||
| Diaphysis (cortical bone) | ||||
| Ma.V | mm3 | 1.22 ± 0.12 | 1.03 ± 0.11 | 0.005 |
| Ct.Th | mm | 0.148 ± 0.011 | 0.124 ± 0.011 | 0.001 |
| Imin | mm4 | 0.102 ± 0.007 | 0.066 ± 0.009 | <0.001 |
| Ct.Ar | mm2 | 0.640 ± 0.033 | 0.4892 ± 0.044 | <0.001 |
| Length | mm | 13.70 ± 0.35 | 12.59 ± 0.36 | <0.001 |
| Slendernessb | mm/mm2 | 20.8 ± 0.7 | 25.1 ± 2.2 | <0.001 |
| Ct.TMD | mgHA/cm3 | 1185 ± 27 | 1176 ± 25 | 0.49 |
| Stiffness | N/mm | 40.7 ± 8.5 | 36.9 ± 12.6 | 0.57 |
| Modulus | GPa | 4.2 ± 0.8 | 6.1 ± 2.6 | 0.137 |
| Bending strength | MPa | 147 ± 17 | 172 ± 36 | 0.177 |
|
| ||||
| Property (female) | Units | IR flox (n = 6) | OIRKO (n = 9) | P-value |
|
| ||||
| Metaphysis (trabecular bone) | ||||
| BV/TV | % | 4.38 ± 0.92 | 4.84 ± 1.52 | 0.52 |
| Tb.N | mm−1 | 3.37 ± 0.33 | 3.35 ± 0.59 | 0.95 |
| Tb.Th | mm | 0.037 ± 0.002 | 0.036 ± 0.004 | 0.53 |
| Tb.Sp | mm | 0.302 ± 0.032 | 0.316 ± 0.084 | 0.69 |
| SMIa | — | 3.19 ± 0.17 | 2.80 ± 0.18 | 0.001 |
| Tb.TMD | mgHA/cm3 | 916 ± 13 | 901 ± 30 | 0.28 |
|
| ||||
| Diaphysis (cortical bone) | ||||
| Ma.V | mm3 | 1.07 ± 0.07 | 1.01 ± 0.08 | 0.16 |
| Ct.Th | mm | 0.162 ± 0.005 | 0.138 ± 0.011 | <0.001 |
| Imin | mm4 | 0.093 ± 0.010 | 0.072 ± 0.007 | <0.001 |
| Ct.Ar | mm2 | 0.651 ± 0.028 | 0.538 ± 0.048 | <0.001 |
| Length | mm | 14.41 ± 0.39 | 13.22 ± 0.45 | <0.001 |
| Slendernessb | mm/mm2 | 21.3 ± 0.687 | 23.5 ± 1.236 | 0.002 |
| Ct.TMD | mgHA/cm3 | 1251 ± 15 | 1209 ± 13 | <0.001 |
| Stiffness | N/mm | 80.6 ± 11.5 | 57.3 ± 6.7 | <0.001 |
| Modulus | GPa | 9.4 ± 1.5 | 8.5 ± 1.2 | 0.26 |
| Bending strength | MPa | 166 ± 10 | 161 ± 13 | 0.50 |
aStructural model index characterizes the shape of trabecular bone (1: platelike; 3: rodlike). bSlenderness is the ratio of the length to the total cross-sectional area of the femur midshaft. Abbreviations: BV/TV: bone volume/tissue volume; Tb.N: trabecular number; Tb.Th: trabecular thickness; Tb.Sp: trabecular separation; SMI: structural model index; Tb.TMD: trabecular tissue mineral density; Ma.V: marrow volume; Ct.Th.: cortical thickness; Imin: moment of inertia; Ct.Ar: cortical area; Ct.TMD: cortical tissue mineral density. Significant differences are highlighted in bold font.