Guided waves in anisotropic and viscoelastic stratified plates: Application to bone quantitative ultrasound

This paper presents a numerical investigation into the behavior of ultrasonic guided waves in a multilayered bone plate characterized by anisotropic and viscoelastic properties. A spectral collocation formula for bone structures is developed, enabling accurate computation of three-dimensional dispersion curves, wave structures, and attenuation of guided waves. Additionally, a mode classification scheme is introduced to identify individual modes, facilitating mode selection during bone inversion. Our results are benchmarked against alternative wave computation methods and experimental data to validate their robustness and reliability. The effects of incorporating soft tissue and marrow into the bone models are explored in relation to mode number, trajectory, and attenuation. With its fast computational speed and mode-classification features, the proposed methodology serves as an effective forward modeling tool for enhanced ultrasonic bone assessment.