Guided waves in cortical bone

Abstract

In the last decade, several experimental studies have shown that long cortical bones act as a natural waveguide at ultrasonic frequencies despite attenuation in bone material and heterogeneity in elastic and geometrical properties. Propagation in waveguides consists in a variety of dispersive waves, each one with its own frequency-dependent field distribution across the section of the waveguide. Guided waves are extensively used particularly in non destructive evaluation. Technologically adapted devices have been developed for instance for structure health monitoring. In the bone assessment field, guided waves analysis might answer to the attempt of multiple bone property determination, as cortical thickness and elasticity. These properties are in turn relevant indicators of biomechanical competence. One of the most promising recent developments in this field is the so called axial transmission technique.