ELASTIC PROPERTIES OF CANCELLOUS BONE

所提议的研究的长期目标是绘制弹性 整个股骨和胫骨的特性作为解剖位置的函数。 在作者以前的工作中，大脑皮层的弹性性质 其中的一部分进行了测量。到目前为止，还没有一种技术可以 可用于从小范围内获得精确的弹性属性值 松质骨标本。因此，拟议工作的很大一部分 就是开发这样一种技术。具有精确的弹性值 属性作为位置的函数是 这些承重骨的力学分析；特别是在有限元分析中 单元分析中精确的弹性模量值，剪切模量值， 泊松比对改善髋关节和膝关节的设计至关重要 假肢。 所提出的研究的具体目标是研制一种超声波 一种可以用来测量小尺寸材料弹性性能的技术 松质骨标本。建议的方法是1)测量 在50千赫至3千赫的频率范围内的超声波速度 MHz，2)通过适当的方法将速度与弹性特性相关联 连续体理论，3)测量材料密度、体积密度和骨骼 超声波试件的矿物含量，4)弹性测量 通过力学方法对相邻试件的性能进行分析，以及5)关联 超声测得的弹性性能与密度、矿物 含量和机械测量的弹性性能，以评估 超声技术的有效性。一旦超声波技术被 松质骨和皮质部的弹性特性 股骨和胫骨的位置将作为解剖位置的函数进行标测。

The long range objective of the proposed research is to map the elastic properties of the entire femur and tibia as a function of anatomical site. In previous work by the author, the elastic properties of the cortical portion of these were measured. To date, there exists no technique that can be used to obtain accurate values of the elastic properties from small specimens of cancellous bone. Hence, a large portion of the proposed work will be to develop such a technique. Having accurate values of the elastic properties as a function of position is a necessary prerequisite to the mechanical analysis of these load bearing bones; particularly in finite element analyses where accurate values of the elastic moduli, shear moduli, and Poisson's ratios are crucial to the design of improved hip and knee prosthetics. The specific aims of the proposed research are the develop an ultrasonic technique that can be used to measure the elastic properties of small specimens of cancellous bone. The proposed methodology is 1) to measure ultrasonic wave velocities over a range of frequencies from 50 kHz to 3 MHz, 2) to relate the velocities to elastic properties by appropriate continuum theories, 3) to measure material density, bulk density, and bone mineral content of the ultrasonic specimens, 4) to measure the elastic properties by mechanical methods on adjacent specimens, and 5) to correlate the ultrasonically measured elastic properties with the densities, mineral content, and mechanically measured elastic properties to evaluate the validity of the ultrasonic technique. Once the ultrasonic technique is developed, the elastic properties of the cancellous and cortical portions of both the femur and tibia will be mapped as a function of anatomical site.