Sutton-Smith Peter, Parkinson Ian H, Linn Andrew M J, Kooke Simone A, Fazzalari Nicola L
Division of Tissue Pathology, Institute of Medical and Veterinary Science, Adelaide, South Australia.
Clin Anat. 2006 Jan;19(1):12-8. doi: 10.1002/ca.20171.
The need for improved mechanistic understanding of cancellous bone failure is at the core of important clinical problems such as osteoporosis, as well as basic biological issues such as bone formation and adaptation. Three-dimensional (3D) anaglyphs were produced from 15 T12 and L1 vertebral bodies, which encompass the adult life span in both sexes. The anaglyphs were viewed with red-green stereo glasses, using an image analyzer, and trabecular thickness and trabecular length were measured. From biomechanical principles, the strength of individual trabeculae can be estimated from measurement of trabecular rod thickness and trabecular rod length as the load to buckling index. The distribution of the load to buckling index was best described by a log normal curve. Trabecular rod thickness, trabecular rod length, and load to buckling index for males were consistently greater than for females. With aging, trabecular rod thickness, and the load to buckling index decrease for males while trabecular rod length increases for females. In this study, the load to buckling index for thoraco-lumbar vertebral trabecular rods potentially quantifies a greater risk of vertebral fracture for females. Decreased trabecular rod thickness or increased trabecular rod length result in the strength of trabeculae shifting closer to a putative fracture threshold. The corollary being that there is a reduced safety margin for resistance to mechanical loads for the vertebral bodies. The 3D anaglyph technique for measuring trabecular dimensions provides an accurate and precise methodology by which these morphological studies can be undertaken.
深入了解松质骨失效机制的需求，是骨质疏松等重要临床问题以及骨形成和适应性等基础生物学问题的核心所在。从15个T12和L1椎体制作了三维（3D）立体图像，这些椎体涵盖了两性的成年寿命阶段。使用图像分析仪，通过红绿立体眼镜观察这些立体图像，并测量小梁厚度和小梁长度。根据生物力学原理，通过测量小梁杆厚度和小梁杆长度作为屈曲负荷指数，可以估算单个小梁的强度。屈曲负荷指数的分布最好用对数正态曲线来描述。男性的小梁杆厚度、小梁杆长度和屈曲负荷指数始终大于女性。随着年龄增长，男性的小梁杆厚度和屈曲负荷指数下降，而女性的小梁杆长度增加。在本研究中，胸腰椎小梁杆的屈曲负荷指数可能量化了女性发生椎体骨折的更高风险。小梁杆厚度减小或小梁杆长度增加会导致小梁强度更接近假定的骨折阈值。由此推论，椎体抵抗机械负荷的安全 margin 降低。用于测量小梁尺寸的3D立体图像技术提供了一种准确而精确的方法，可借此开展这些形态学研究。 （注：原文中“safety margin”直译为“安全边际”，结合语境这里译为“安全裕度”更合适，但按要求未做修改）
