COMPUTER ASSISTED MICROSTRUCTURAL ANALYSIS OF CANCELLOUS BONE.

Attempts to provide detailed microstructural analysis of cancellous bone thus far have been hampered due to the difficulty in measuring and characterizing anisotropy of this porous material. A recently described mean intercept length tensor, based on measurements made in any three mutually perpendicular planes) allows fully three dimensional quantifications of microstructural anisotropy of trabecular bone. This tensorial representation provides especially facile incorporation of material anisotropy into stress-strain relations, since both stress and strain are also second rank tensors. This tensor should thus prove useful in quantitatively studying bone remodelling in pathologic states and in reaction to joint arthroplasty. To avoid the tedium of manual quantification of trabecular orientation levels, we have developed an automated system which enables accurate, routine measurements of the mean intercept length tensor in cancellous bone, and which also generates routine microstructural measurements such as volumetric density, and trabecular widths.