Micro-CT examinations of trabecular bone samples at different resolutions: 14, 7 and 2 micron level.

Tomographic techniques are attractive for the investigation of trabecular bone architecture. Using either conventional X-ray sources or synchrotron sources currently allows the acquisition of 3D images in a wide range of spatial resolution that may be as small as a few micrometers. Since it is technically possible to examine trabecular architecture at different scales, a question is to know what type of information it is possible to get at each scale. For this purpose, a series of ten vertebrae samples from healthy females of different ages (33 to 90) was imaged at various resolutions on three different micro-CT systems (cubic voxel size respectively 14, 6.7 and 1.4 microm). The comparison of morphometric parameters extracted from the different images is in agreement with simulation results on the influence of spatial resolution on structure parameters. The conclusion is that a 14 microm voxel size gives a reasonably good parameterisation of trabecular architecture. Besides the synchrotron radiation 2 microm level images reveal interesting features on the irregularities and rupture of trabecular surface, and on remodeling zones.