Beyond Bone Mineral Density: Detecting Changes in Fracture Risk in the Absence of Mineral Loss with the Mechanical Response Tissue Analyzer

• Main Author: Gaspar, Anne Elizabeth
• Other Authors: Grynpas, Marc D.
• Language: en_ca
• Published: 2013
• Subjects: mechanical response tissue analyzer (MRTA); fracture risk; bone collagen; bone fatigue; 0541; 0548
• Online Access: http://hdl.handle.net/1807/42855

The ability of current clinical tools to predict bone fractures is poor, likely because these tools focus on bone mass and mineral content and neglect bone quality and the collagen phase. The Mechanical Response Tissue Analyzer (MRTA) is an instrument that provides a non-invasive mechanical measurement of the whole bone. It has traditionally been used to obtain a bone stiffness constant (Kb), but can provide a bone damping constant (Bb) that has not previously been considered. The goal of this research is to determine whether the MRTA can detect three damage modes that do not alter bone mass or mineral density: γ-irradiation, collagen over-crosslinking, and fatigue. The MRTA detected a reduction in Bb due to over-crosslinking. Fatigue was found to increase Bb and decrease Kb, and these changes were confirmed through dynamic bending tests. The MRTA shows potential to diagnose increased fracture risk in scenarios where damage is currently undetectable.