Mean Trabecular Density Research Articles

Feasibility of diagnosing osteoporosis using routine computed tomography scans for hip fractures: Correlation with histopathological diagnosis of head and neck regions.

The aim of this study was to demonstrate the feasibility of diagnosing osteoporosis through routine computed tomography (CT) by assessing the association between the histopathological assessment of femoral head specimens extracted from patients who underwent surgery for intertrochanteric fractures and the Hounsfield unit (HU) measurements derived from preoperative CT scans. Forty-eight patients who presented to our clinic between November 2019 and May 2020 with hip fractures and underwent partial prosthesis fixation were included in this retrospective study. Hounsfield unit measurements were performed on the head and neck regions using dual-energy x-ray absorptiometry (DEXA) and CT scans, respectively. The trabecular ratio per unit area was calculated using the Nikon Imaging Software (NIS-Elements ) program in the pathology laboratory from digitally captured images of the removed head and neck specimens. The mean HU receiver operating characteristic analysis had a sensitivity of 77% and a specificity of 87%, with a cutoff value of 77.68. There was a moderate correlation between the mean trabecular density and the mean HU of the femoral head (P=0.013, r=0.340). Additionally, there was a significant correlation between the mean HU and the T-score of the head, although this correlation was not found with the maximum-minimum HU. Although there was a significant correlation between trabecular density and mean HU, the correlation coefficient indicated a moderate relationship. This relationship was also observed between the inferior sections of the head and the trabecular density and HU (P=.018). However, no significant correlation was found between the T-score and the trabecular structure of the head (P=.977). The results of the present study suggest that conventional CT has the potential to serve as a diagnostic tool for osteoporosis and may offer a more precise and accurate method for evaluating the success of intraosseous implants when compared to T-scores without the need for additional tests or procedures.

Cluster analysis of bone microarchitecture from high resolution peripheral quantitative computed tomography demonstrates two separate phenotypes associated with high fracture risk in men and women

Osteoporosis is a major healthcare problem which is conventionally assessed by dual energy X-ray absorptiometry (DXA). New technologies such as high resolution peripheral quantitative computed tomography (HRpQCT) also predict fracture risk. HRpQCT measures a number of bone characteristics that may inform specific patterns of bone deficits. We used cluster analysis to define different bone phenotypes and their relationships to fracture prevalence and areal bone mineral density (BMD). 177 men and 159 women, in whom fracture history was determined by self-report and vertebral fracture assessment, underwent HRpQCT of the distal radius and femoral neck DXA. Five clusters were derived with two clusters associated with elevated fracture risk. “Cluster 1” contained 26 women (50.0% fractured) and 30 men (50.0% fractured) with a lower mean cortical thickness and cortical volumetric BMD, and in men only, a mean total and trabecular area more than the sex-specific cohort mean. “Cluster 2” contained 20 women (50.0% fractured) and 14 men (35.7% fractured) with a lower mean trabecular density and trabecular number than the sex-specific cohort mean. Logistic regression showed fracture rates in these clusters to be significantly higher than the lowest fracture risk cluster [5] (p<0.05). Mean femoral neck areal BMD was significantly lower than cluster 5 in women in cluster 1 and 2 (p<0.001 for both), and in men, in cluster 2 (p<0.001) but not 1 (p=0.220). In conclusion, this study demonstrates two distinct high risk clusters in both men and women which may differ in etiology and response to treatment. As cluster 1 in men does not have low areal BMD, these men may not be identified as high risk by conventional DXA alone.

Enhanced bone structural analysis through pQCT image preprocessing

Several factors, including preprocessing of the image, can affect the reliability of pQCT-measured bone traits, such as cortical area and trabecular density. Using repeated scans of four different liquid phantoms and repeated in vivo scans of distal tibiae from 25 subjects, the performance of two novel preprocessing methods, based on the down-sampling of grayscale intensity histogram and the statistical approximation of image data, was compared to 3 × 3 and 5 × 5 median filtering. According to phantom measurements, the signal to noise ratio in the raw pQCT images (XCT 3000) was low (∼20 dB) which posed a challenge for preprocessing. Concerning the cortical analysis, the reliability coefficient ( R) was 67% for the raw image and increased to 94–97% after preprocessing without apparent preference for any method. Concerning the trabecular density, the R-values were already high (∼99%) in the raw images leaving virtually no room for improvement. However, some coarse structural patterns could be seen in the preprocessed images in contrast to a disperse distribution of density levels in the raw image. In conclusion, preprocessing cannot suppress the high noise level to the extent that the analysis of mean trabecular density is essentially improved, whereas preprocessing can enhance cortical bone analysis and also facilitate coarse structural analyses of the trabecular region.

Bone density comparison of selected carpal and tarsal bones: validation for their use in compression fracture fixation studies of scaphoid screws

To determine if trabecular, total and cortical bone densities of the capitate, navicular, cuboid, and first cuneiform were equivalent to those of the scaphoid, such that these bones could be used in place of the scaphoid in evaluating new headless scaphoid compression screws. Fifty scaphoids, capitates, naviculars, cuboids, and first cuneiforms were harvested from fresh frozen cadavers. The trabecular, total and cortical bone densities were measured using pQCT technology and statistically compared. A paired t comparison between paired scaphoids and capitates showed no difference between the trabecular bone densities. However, their total bone and cortical densities were found to be different. An independent measures ANOVA comparison of the five bones, showed no significant difference in mean trabecular density between the capitates, naviculars and first cuneiforms when compared to the scaphoids. However, the mean total and cortical densities of the first cuneiforms were less than the scaphoids and the mean trabecular, total and cortical bone densities of the cuboids were all less than the scaphoids. Compression fracture fixation studies of headless compression screws could be conducted using the capitate, navicular, and first cuneiform as models of the scaphoid when the supply of scaphoids is limited.

Compositional analysis of the collagenous bone matrix. A study on adult normal and osteopenic bone tissue.

The collagenous constituents of mature bone of 30 individuals 22-93 years of age were studied by post-mortem morphological and biochemical analysis. Morphometric evaluation of the second lumbar vertebral body revealed striking interindividual differences in bone mass, mean trabecular density and mean trabecular thickness. Collagen extracted from vertebral trabecular bone by limited pepsin digestion consisted mainly of collagen I (92%) and collagen V (8%). Immunohistochemistry revealed a distinct distribution of these two collagen types within the bone matrix. The degree of lysyl hydroxylation of the alpha 2(I) collagen chain correlated inversely with the trabecular bone volume (TBV) and with the mean trabecular plate density. This correlation was statistically significant for the entire study group as well as for the female and male subgroups. Within the female subgroup, the lysyl hydroxylation/TBV ratio was higher in postmenopausal than in premenopausal women and was highest in women with established osteoporosis. No significant correlation was found between the level of lysyl hydroxylation and the age of the patients. The alpha 1(I) collagen chain showed a nearly constant degree of lysyl hydroxylation in all 30 samples. The results provide convincing evidence that morphometric changes associated with osteopenia in adult bone are accompanied by an altered level of lysyl hydroxylation of the alpha 2(I)-chain of collagen I. The biochemical alterations observed may be responsible for the deposition of a deficient bone matrix in osteopenic conditions.