Academic Unit of Bone Metabolism at the University of Sheffield, and Sheffield Teaching Hospitals National Health Service Foundation Trust, Sheffield S5 7AU, United Kingdom.
J Clin Endocrinol Metab. 2012 Sep;97(9):3342-8. doi: 10.1210/jc.2012-1677. Epub 2012 Jul 3.
Bone size, geometry, density, and microarchitecture are important determinants of bone strength. By understanding how these properties change during skeletal development, we can better understand bone fragility.
The aim of the study was to compare the geometry, microarchitecture, and strength of the radius and tibia in men and women at the end of adolescence and in young adulthood and to relate these properties to biochemical bone turnover markers and bone regulatory hormones.
We conducted a cross-sectional study of 116 healthy men and women ages 16-18 (n = 56) and 30-32 (n = 60) yr.
We used high-resolution peripheral quantitative computed tomography to measure bone size, geometry, and microarchitecture at the distal radius and tibia and micro-finite element modeling to estimate bone strength. We measured bone turnover markers (β C-terminal telopeptide of type I collagen and amino-terminal propeptide of type I procollagen) and hormones known to affect bone metabolism (estradiol, testosterone, IGF-I, and PTH).
Bone strength was greater in men than in women, and at the radius it was greater in men ages 30-32 yr than ages 16-18 yr. The gender difference was due to greater cortical perimeter, trabecular area, and trabecular density in men. The age difference was due to greater cortical thickness and cortical tissue mineral density and lower cortical porosity. IGF-I was related to two of these five key properties at the radius (cortical perimeter and cortical thickness). None of the hormones were predictors of density or structure at the tibia.
Cortical modeling of long bones continues beyond the end of adolescence. IGF-I may be a determinant of this process at the radius.
骨大小、几何形状、密度和微观结构是骨骼强度的重要决定因素。通过了解这些特性在骨骼发育过程中的变化，我们可以更好地了解骨骼脆性。
本研究的目的是比较青少年末期和成年早期男性和女性桡骨和胫骨的几何形状、微观结构和强度，并将这些特性与生化骨转换标志物和骨调节激素相关联。
我们对 116 名年龄在 16-18 岁（n=56）和 30-32 岁（n=60）的健康男性和女性进行了横断面研究。
我们使用高分辨率外周定量计算机断层扫描技术测量桡骨和胫骨远端的骨大小、几何形状和微观结构，并采用微有限元建模技术估计骨强度。我们测量了骨转换标志物（I 型胶原 C 端肽和 I 型前胶原氨基端原肽）和已知影响骨代谢的激素（雌二醇、睾酮、IGF-I 和 PTH）。
骨强度在男性中大于女性，而在 30-32 岁的男性中大于 16-18 岁的男性。这种性别差异是由于男性的皮质周长、骨小梁面积和骨小梁密度较大所致。年龄差异是由于皮质厚度和皮质组织矿物质密度增加以及皮质孔隙率降低所致。IGF-I 与桡骨的五个关键特性中的两个有关（皮质周长和皮质厚度）。没有一种激素可以预测胫骨的密度或结构。
皮质骨的长骨模型化在青春期结束后仍在继续。IGF-I 可能是桡骨这一过程的决定因素。
