Unraveling the Role of Structure and Density in Determining Vertebral Bone Strength

Abstract

The strength of bone is determined not only by bone density but also by structure. Therefore, quantification of the structure in radiographs by texture parameters may result in a better prediction of fracture risk. Since in radiographs density and structure are strongly correlated, the predictive power of texture parameters should be corrected for the influence of BMD to determine the additional information conveyed by these parameters. In this study, we evaluated the predictive power of various texture parameters based on the Grey-Level Dependence Method and the Morphological Gradient Method. This study was performed on 67 vertebrae obtained from 20 male and 12 female human cadaver thoracolumbar spines. BMD and area of the vertebral body were determined from QCT images and texture parameters were derived from direct magnification (DIMA) radiographs. The fracture force, measured under conditions simulating the in vivo situation, was corrected with the area of the vertebra to yield the fracture stress (FS). Results of the study indicate that BMD correlates significantly with FS r = 0.82 (P < 0. 001, n = 24) and r = 0.94 (P < 0.001, n = 43) for female and male vertebrae, respectively. Correlation coefficients of the investigated texture parameters were as high as 0.80 (P < 0.001) and 0.67 (P < 0.001) for the female and male vertebrae, respectively. Multiple regression analysis showed that in female vertebrae, the addition of one texture parameter to BMD results in a better prediction of strength. The multiple correlation coefficient was 0. 87 (P < 0.001) in this case. In male vertebrae, BMD was the best predictor of fracture stress. These results suggest that texture parameters, as measured in magnification radiographs, can predict bone strength. Whereas in all cases BMD is the best single predictor of bone strength, for women texture parameters contain useful additional information.

Areal Distribution of Preferential Alignment of Biological Apatite (BAp) Crystallite on Cross-Section of Center of Femoral Diaphysis in Osteopetrotic (op/op) Mouse

“…3) Recent research suggests that bone mineral density (BMD) is not a sufficient predictor of whole bone mechanical properties, while BMD is related to bone strength and fracture risk. 4,5) In untreated patients with the same BMD, fracture risk varies with age and perhaps with gender and race. 6) Therefore, the influences of still unidentified parameters controlling bone mechanical properties should be determined.…”

3d Gray-Level Histomorphometry of Trabecular Bone - A Methodological Review

“…In most cases multiple regression models are tested to check whether inclusion of texture parameters increases determination coefficient of parameters directly related to fracture risk e.g., fracture strength or apparent Young's modulus as compared to bone density only. The published results are not however encouraging -the texture analysis improves the prediction of mechanical parameters by at most a few percent (Veenland et al, 1997;Cortet et al, 1999).…”

“…In particular, the gray-level images of trabecular bone have been analyzed, using the methods developed for texture characterization. One of the possible approaches is based on the co-occurrence of matrix and its derived parameters (Haralick et al, 1973;Veenland et al, 1997). Firstly, histogram equalization is performed: the number of gray levels is reduced to some number N and gray-level intensities are redistributed in such way that the probability of occurrence for all gray-levels is equalized.…”

Gray-Level Co-occurrence Matrix Bone Fracture Detection

“…Materka et al (2000) bone mineral density estimated by means of Dualphoton Absorptiometry (DXA) based on cooccurrence matrix texture analysis by computing the standard DXA technique and the image mean, standard deviation, skewness, kurtosis, energy, entropy, fractal dimension in vertical dimension and variance-based fractal dimension and examine their correlations. Veenland et al (1997) suggested that the power of texture parameters is corrected for the influence of BMD to determine the additional information indicated by these parameters since in radiographs density and structure are strongly correlated. The predictive power of these texture parameters are obtained through the Grey-Level Dependence Method and the Morphological Gradient Method by examining Correlation coefficients of the investigated texture parameters…”