Rho J Y, Ashman R B, Turner C H
Department of Orthopaedic Surgery, State University of New York, Buffalo.
J Biomech. 1993 Feb;26(2):111-9. doi: 10.1016/0021-9290(93)90042-d.
An ultrasonic technique and microtensile testing were used to determine the Young's modulus of individual trabeculae and micro-specimens of cortical bone cut to similar size as individual trabeculae. The average trabecular Young's modulus measured ultrasonically and mechanically was 14.8 GPa (S.D. 1.4) and 10.4 (S.D. 3.5) and the average Young's modulus of microspecimens of cortical bone measured ultrasonically and mechanically was 20.7 GPa (S.D. 1.9) and 18.6 GPa (S.D. 3.5). With either testing technique the mean trabecular Young's modulus was found to be significantly less than that of cortical bone (p < 0.0001). However, the specimens were dried before microtensile testing so Young's modulus values may have been greater than those of trabeculae in vivo. Using Young's modulus measurements obtained from 450 cubes of cancellous bone and 256 cubes of cortical bone, Wolff's hypothesis that cortical bone is simply dense cancellous bone was tested. A multiple regression analysis that controlled for group membership showed that Young's modulus of cortical bone cannot be extrapolated from the Young's modulus vs density relationship for cancellous bone, yet the Young's modulus of trabeculae can be predicted by extrapolation from the relationship between Young's modulus vs density of the cancellous bone. These results suggest that when considered mechanically, cortical and trabecular bone are not the same material.
采用超声技术和微拉伸试验来测定单个小梁以及切割成与单个小梁尺寸相似的皮质骨微标本的杨氏模量。超声法和机械法测得的小梁平均杨氏模量分别为14.8 GPa（标准差1.4）和10.4（标准差3.5），超声法和机械法测得的皮质骨微标本的平均杨氏模量分别为20.7 GPa（标准差1.9）和18.6 GPa（标准差3.5）。无论采用哪种测试技术，均发现小梁的平均杨氏模量显著低于皮质骨（p < 0.0001）。然而，在进行微拉伸试验前标本已干燥，因此杨氏模量值可能高于小梁在体内时的值。利用从450个松质骨立方体和256个皮质骨立方体获得的杨氏模量测量值，对沃尔夫关于皮质骨只是致密松质骨的假说进行了检验。一项控制了组别的多元回归分析表明，皮质骨的杨氏模量不能从松质骨杨氏模量与密度的关系中推断得出，而小梁的杨氏模量可以通过从松质骨杨氏模量与密度的关系中进行外推来预测。这些结果表明，从力学角度考虑，皮质骨和小梁骨不是同一种材料。
