Figure 5.

Femoral diaphyseal structural and cortical bone material biomechanical properties determined by torsional loading to failure. Diaphyseal A) torsional loading to failure T_max and cortical bone B) tensile strength Su improve with age in both strains and genotypes, although oim/oim remain weaker than Wt at all ages. Diaphyseal E) energy to failure U was significantly reduced in oim/oim femurs as compared to Wt in both strains and at all ages. Diaphyseal C) torsional stiffness K and cortical bone D) shear modulus of elasticity G increased in both strains and genotypes with age. ^ap≤0.05 as compared to Wt femurs of the same strain and age; ^bp≤0.05 as compared to outbred femurs of the same genotype and age; ^cp≤0.05 as compared to 2 month femurs of the same genotype and strain; ^dp≤0.05 as compared to 4 month femurs of the same genotype and strain. [per age class: Wt, n=8–12; oim/+, n=6–12; oim/oim, n=6–12]