An animal model (the ewe) was used to study mechanical parameters of cancellous bone specimens. Compression and shear tests were conducted on ewe vertebral trabecular bone (L1–L5) from old ewes (mean age: 9 years) under two different conditions: first, at room temperature in air (“standard” test conditions); and secondly, in a physiological saline bath regulated at 37°C. The parameters obtained under “standard” test conditions with a uniaxial compression test were the mean value of the maximum strength (εσmax=22.3 (7.06) MPa), Young's modulus (E=1510 (784) MPa), the strain at maximum strength (εσmax=3.21 (0.8) percent) and the energy absorbed during the test (W=0.3 (0.12) MJ.m−3). No significant change was found when the test was carried out in a saline bath at 37°C (p<0.0005). An original shear test was performed to evaluate the shear strength which was found to vary from 7.5 (4.7) to 14.6 (8.53) MPa under “standard” test conditions depending on the method of calculation. Testing of the specimens in a 37°C physiological saline bath induced a decrease in the shear strength from 32.5 percent (p<0.0005) to 37.3 percent (p<0.001) of those measured under “standard” test conditions.
The non-destructive measurement of the Bone Mineral Density (BMD) accounted for up to 73.3 percent of the maximum compressive strength σmax and 61.5 percent of the maximum shear strength τmax determined in saline solution at 37°C. These results showed that other parameters influencing the mechanical properties of trabecular bone and its structure appeared to be essential.