TEXTURE ANALYSIS OF DIRECT MAGNIFICATION RADIOGRAPHS OF VERTEBRAL SPECIMENS - CORRELATION WITH BONE-MINERAL DENSITY AND BIOMECHANICAL PROPERTIES

Rationale and Objectives. The authors used direct magnification radiog raphs, combined with texture analysis, to investigate the trabecular s tructure of human vertebral specimens and compared these techniques wi th measurement of bone mineral density (BMD) by using quantitative com puted tomography to predict bone strength. Methods. Direct magnificati on radiographs and BMD measurements were obtained from 38 motion segme nts from the thoracolumbar spines of 11 female human cadavers. Maximum compressive strength (MCS) was determined with a materials testing ma chine. Morphologic parameters, digital skeletons, and fractal dimensio n were obtained from the radiographs in three different regions of int erest. Results. Correlations between BMD and MCS were statistically si gnificant (r = .81, P < .01). With morphologic parameters, correlation coefficients of up to .64 (P < .01) were obtained. Use of multivariat e regression analysis with one morphologic parameter (the width of the black pixels, or thickness,) in addition to BMD improved correlations versus MCS (P < .01). Conclusion. In an experimental setting, BMD sho wed statistically significant correlation with bone strength, whereas the structural parameters demonstrated only modest correlations. BMD t ogether with one of these measures (thickness,), however, showed the h ighest correlation.