Correlation analysis of bone vibration frequency and its mass: volume ratio

Background: Vibration analysis is a well-established technique in industry to analyse materials physical properties. The application to bone’s physical properties is unclear. This study investigated the relationship between bone vibration frequency and mass:volume ratio (ρ). Methods: We used eight turkey bones (tibio tursus). Following soft tissue removal, a 12 cm diaphyseal section was isolated, marrow removed using a water jet and the bones dried at 25 °C for 1 week. Bone volume was determined by water displacement, and mass by weighing. Bones were held in a vice at one end in a consistent manner and vibrated either using a miniature vibration motor (continuous vibration approach) or a miniature electronic hammer (impulse vibration approach). Vibration signals were recorded using CM-01B sensor. For the impulse approach, the highest peak in the magnitude frequency spectrum of the vibration signal (F) was used to determine the bone vibration frequency. For the continuous vibration approach, the difference (FD) between the motor vibration frequency and the bone vibration frequency (obtained from the highest peak in the magnitude frequency spectrum) was used. Results: The impulse approach correlated more strongly with ρ than did the continuous approach (correlation of F with ρ 0.57 vs 0.38 respectively). Summary: This study suggests that vibration analysis may be a valuable technique in assessing bone mass/volume properties. This was a preliminary study and we are currently conducting a larger study to explore the findings further.