62岁和69岁椎体松质骨表观弹性模量与骨量的关系

为研究松质骨的力学性能与骨量的关系,从62岁和69岁男性第4腰椎椎体取出共90个松质骨样本,用M icro-CT系统扫描后,转换成显微有限元模型,经计算得到主轴方向和非主轴方向的表观弹性模量。结果显示,62岁组椎体松质骨3个正交方向的表观弹性模量都显著大于69岁组。不同年龄、不同方向表观弹性模量与骨量遵循不同的关系式。本研究表明:62岁椎体主轴方向的表观弹性模量的变化主要是由骨量的变化决定的;而随着年龄的增长,无论是主轴方向还是非主轴方向,力学性能的降低更多地受显微结构形态退化的影响。

Relationship between apparent elastic modulus and bone volume of 62 year old and 69 year old vertebral trabeculae

This paper investigates the relationship between the mechanical properties and the volume of cancellous bone.Ninety L4 vertebral trabecular specimens obtained from 62 year old and 69 year old males were scanned using a micro-computed tomography(Micro-CT) system and then converted to micro-finite element models.The apparent elastic moduli in the three orthogonal directions of the 62 year old group were all significantly greater than those of the 69 year old group. The relationships between the elastic modulus and the bone volume differed with age and orientation.The apparent elastic moduli in the on-axis direction of the 62 year old group were mainly determined by the bone volume;however,deterioration of the micro-architecture of the senile vertebral trabecular bone plays a more important role in explaining the decrease of both on-axis and off-axis mechanical properties with ageing.