Improvements to mechanical response tissue analysis

Cortical Bone Mechanics Technology™ (CBMT) comprises certain improvements over a previous method known as Mechanical Response Tissue Analysis (MRTA). Both methods are dynamic 3-point bending tests intended for measuring the mechanical properties of cortical bone in living people. MRTA presented a theoretical potential for direct measurement of skeletal fragility, but it had acquired a reputation for error and fallen into disuse. We found sources of error in both MRTA data collection and data analysis. We describe here the fundamentals of MRTA, the major sources of error we found in MRTA, and our innovations for avoiding them. • Data collection at many sites across the mid-shaft of the ulna bone in the forearm. • Parameter estimation by fitting analytical complex compliance and stiffness transfer functions to empirical complex compliance and stiffness frequency response functions. • Optimization by selecting results from frequency response functions with the smallest deviations between fits to compliance and stiffness frequency response functions.