Although bone mass is a contributory risk factor for hip fracture, its distribution about the femoral neck is also important. Femoral neck biopsies were obtained from 13 females with intracapsular hip fracture (fracture: mean age 74.3 ± 2.3 years [SEM]) and 19 cadaveric samples (control: 9 males and 10 females 79.4 ± 1.7 years) and the areas of cortical and cancellous bone were quantitated in octants. In the control group, although males had larger bones than females, the proportions of cortical and cancellous bone were not different (p > 0.05) between the genders. The total amount of bone, as a proportion of bone + marrow, was significantly reduced in the fractures compared with the female controls (%Tt.Ar: fracture 27.83 ± 1.18, female control 33.62 ± 1.47; p = 0.0054). Reductions in cortical bone area occurred in all regions but particularly in the inferior, inferoanterior, and anterior octants (p < 0.05). There were no differences between cases and controls in the regional amount of cancellous bone (all regions, p > 0.178). Marked reductions in mean cortical bone width between the fracture and female control group occurred in the anterior, inferoanterior (31%), and superoposterior (25%) regions. Representing cortical widths as simple Fourier functions of the angle about the center of area (R 2 adj = 0.79) showed in the cases that there was preservation of the cortical bone in the inferior region, with the proportional loss of cortical bone being greatest in the inferoanterior and superoposterior regions. It is concluded that loss of cortical, rather than cancellous, bone predominates in cases of femoral neck fracture. This loss occurs primarily along the inferoanterior to superoposterior axis. As this axis bears the greatest strain during a fall, it is hypothesized that specific thinning of the cortex in these regions leads to an exaggerated propensity to fracture in those so affected, above that resulting from an equivalent general decrease in bone mass. (J Bone Miner Res 1999;14:111-119)
A new method is described for the analysis of the two-dimensional structural pattern of uabecular bone in human iliac crest biopsies. 8 pm thick undecalcified sections stained with the von Kossa technique were examined at a magnification of x9. Using an Ibas I1 image analyser, the ratio of nodes to free ends and the length of different strut types (cortex to free end, node or cortex, free end to free end and node to node, loop or free end) expressed as a percentage of total strut length were assessed.The reproducibility of the method was good for most of the measured indices but inter-observer and inter-section variation were greater. Comparison of biopsy sections obtained from eleven young healthy control subjects and eleven patients with hepatic osteoporosis revealed a significantly higher node to free end ratio, node to loop and node to node strut length and significantly lower cortex to free end and free end to free end strut length in the controls. No significant differences were seen in node to free end, cortex to cortex or cortex to node strut length. This approach to trabecular bone structure analysis should prove useful in determining patterns of bone loss in health and disease and in examining the effects of treatment on bone structure in osteoporosis.
Organ transplantation is associated with increased bone loss and high fracture risk, but the pathophysiological mechanisms responsible have not been established. We have performed a histomorphometric analysis of bone remodeling before and 3 months after liver transplantation in 21 patients (14 male, 7 female) aged 38-68 years with chronic liver disease. Eight-micrometer undecalcified sections of trans-iliac biopsies were assessed using image analysis. Preoperatively, bone turnover was low with a tendency toward reduced wall width and erosion depth. The bone formation rate increased from 0.021 ± 0.016 (mean ± SD) to 0.067 ± 0.055 µm
This study reports the results of quantitative analysis of iliac bone histology in adults with cystic fibrosis (CF) and low bone mineral density (BMD). Twenty patients with CF had bone biopsies taken after double tetracycline labeling. Histomorphometric measurements were made by image analysis, and data were compared with those of healthy control subjects. Cancellous bone area was lower in the patients with CF (p = 0.003), and there was a trend towards a decrease in cancellous bone connectivity. Bone formation rate at tissue level was significantly lower in patients with CF (p = 0.0002). Wall width, representing the amount of bone formed within individual remodeling units, was decreased (p < 0.0001), as was mineralizing perimeter and mineral apposition rate. Analysis of resorption cavities revealed lower cavity area, reconstructed surface lengths, and cavity depths (p < 0.003) in patients with CF, whereas eroded surface area was higher (p = 0.0004). Our results demonstrate low cancellous bone volume in adult patients with CF with low BMD, the main cause of which appears to be low bone formation at tissue and cellular level. Osteomalacia was diagnosed in one patient. This condition should be excluded as a cause of low bone mineral density in patients with CF and vitamin D insufficiency corrected.
Background and Methods. The known spatial interaction between normal breast epithelium and its surrounding stroma prompted an investigation of the spatial relationship between stromal mitoses and the epithelial component of fibroepithelial tumors of the breast. The authors applied a novel computerized morphometric technique to routinely processed histologic sections of 23 fibroepithelial tumors (13 fibroadenomas and 10 phyllodes tumors). The proportional area of epithelium in successive concentric annuli surrounding stromal mitoses was measured, and its distribution was compared with that around suitable control points. Results. The authors found that stromal mitotic activity in these tumors was significantly more likely to occur close to rather than remote from the epithelial component, with a significant excess of epithelium around mitoses compared with control points within a range of 79 microns. Essentially similar findings were obtained when randomly identified fibroblast nuclei were used as control points, thus obviating variations in stromal cell density with distance from epithelium as an explanation for the findings. Conclusions. These findings support the hypothesis that stromal growth in fibroepithelial tumors depends, to a variable extent, on the epithelial component. An interaction in the opposite direction (i.e., the stroma providing the growth support to the epithelium) also may occur, but this was not investigated. It is suggested that there is an interdependence of growth between the epithelial and stromal components in these tumors that explains their complex morphology and that stromal dependence on epithelium is lost with increasing malignancy of the stromal elements.
The data confirm that the greatest neuronal loss occurs in the RGCL in human glaucoma. Neuronal loss was also observed in the outer retinal layers (INL and ONL) that correlated spatially with changes in the RGCL. Further work is necessary to confirm whether these changes arise from transneuronal degeneration.
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