Biomechanical properties across trabeculae from the proximal femur of normal and ovariectomised sheep

Temporal Changes in Bone Composition, Architecture, and Strength Following Estrogen Deficiency in Osteoporosis

“…The current study found no significant reduction in mineral-to-matrix ratio at twelve months although a strong downward trend was evident (p=0.1) however, by thirty-one months this reduction in ratio had reached statistical significance. This result supports previous work on this animal cohort which has shown through the use of quantitative backscatter electron imaging that mineral content is reduced following estrogen deficiency in the femur [6,7]. However, another study has showed that changes do not occur ubiquitously throughout the proximal femur [8].…”

“…There is evidence that a change in the composition of the bone tissue occurs during estrogen deficiency. Studies have shown that estrogen deficiency reduces the mean bone mineral density [6,7] while others have shown an increase in mineralisation [5]. Interestingly a recent study showed the distribution of tissue level mineral is more heterogeneous in osteoporotic femurs and also that these changes are 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 F o r P e e r R e v i e w 6 anatomically distinct and do not occur uniformly throughout the proximal femur [8].…”

Nanostructure and elastic modulus of single trabecula in bovine cancellous bone

“…Nanoindentation tests were also conducted to obtain the elastic modulus and hardness (Tjhia et al, 2011;Smith et al, 2010;Wolfram et al, 2010;Brennan et al, 2009;Rho et al, 1999); however, the measured values did not necessarily correspond to those obtained in the testing of the whole trabecula. Tensile tests have some advantages over bending tests; for instance, mechanical anisotropy and the inhomogeneous shape of specimens do not severely affect the elastic modulus in the loading direction.…”

Estrogen Plus Estrogen Receptor Antagonists Alter Mineral Production by Osteoblasts In Vitro

“…In early postmenopausal women and ovariectomised rats and sheep, estrogen withdrawal is associated with increased bone turnover resulting in a decrease in whole bone and tissue biomechanical properties [5][6][7][8][9]. Interestingly, although osteoporosis reduces bone mass and structural strength, a recent study found that the remaining bone tissue is significantly stronger and stiffer [10].…”