Comparison of radiometric and histometric features of bone samples from ribs.

OBJECTIVE To correlate quantitative data gathered from conventional radiograms as well as from quantitative computed tomography (QCT) images of bone samples with histometric coefficients of the same specimens. STUDY DESIGN Bone samples were obtained from standardized sites of ribs during autopsy of 40 males aged 15-84 years. In the bone samples the following assessments were performed: densitometry of bone using QCT, estimation of radiostructural quantitative coefficients (coefficient of trabecular arrangement anisotropy, trabecular thickness coefficient); histometry (area of bone matrix, trabecular thickness coefficient); relative weights of dry, decalcified bone and bone in ash form; and concentration of calcium in ash. Radiometry and histometry were performed using image analysis methods with IBAS for Windows (Kontron, Eching b. München, Germany) equipment. Radiostructure of bone was evaluated with the use of our own algorithm; concentration of calcium was measured spectrophotometrically. Analysis of variance, cross correlation, regression analysis and others were the statistical tools applied. RESULTS From the variables analyzed, the following indicates a significant correlation with the histometric area of bone matrix: radiologic trabecular anisotropy, QCT densitometry (especially of cancellous bone) and the ratio of weight of dry sample to fresh sample. The coefficient of radiologic trabecular thickness appeared not to be a valuable feature for estimation of bone histology. CONCLUSION Quantitative estimation of radiostructure of bone carried out on conventional radiograms may be helpful in the detection of histologic properties of bone, an important factor in assessment of the fragility of bone.