Characterization of Human Cortical and Trabecular Bone Structural Change by NMR and Micro-CT

Abstract

The techniques of low-field pulsed proton nuclear magnetic resonance (NMR) spin relaxation and Micro-CT are described for assessment of structural changes of human cortical and trabecular bone in vitro. The technique involves spin-spin relaxation measurement and inversion spin-spin spectral analysis methods for NMR. From NMR measurement, the CPMG T2 relaxation data can be inverted to T2 relaxation distribution and this distribution then can be transformed to a pore size distribution with the longer relaxation times corresponding to larger pores. In Micro-CT measurement, each trabecular bone specimen was individually scanned using a micro-computed tomography (micro-CT) system and 12 micron dimensionally-isotropic voxels were reconstructed. Due to the resolution limitation, Micro-CT measurement on cortical bone was not success, however, NMR measurement was success for both cortical and trabecular bones.