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Bone marrow involvement by breast carcinoma in the absence of demonstrable bone lesions is unusual. We report six patients with medullary tumor without demonstration of cortical bone abnormality on scan or radiographs. This represents 2.8% of 213 patients with breast cancer in which bone marrow examination was performed and 6.2% of those in which marrow involvement was demonstrated.
In femoral cortical bone of 16 uremic patients with long standing renal insufficiency an increased fraction of woven bone was found both in Haversian and in interstitial bone. Either partly resorbed Haversian systems were replaced by non lamellar woven bone or single Haversian systems showed partly well organized lamellar bone and partly disorganized non lamellar texture without signs of antecedent resorption. The replacement of lamellar bone by woven bone was measured morphometrically in undecalcified ground sections. Woven bone was defined by its lack of structural birefringence under polarized light. In advanced cases of secondary hyperparathyroidism more than 60% of cortical bone were composed of woven bone. The substitution of immature less organized woven bone for mature well orfanized lamellar bone has important implications for the biomechanical properties of the skeleton.
One hundred and forty-four solitary bone cysts were treated by curettage and packing with freeze-dried crushed cortical-bone allograft. One hundred and eight healed primarily. There was a higher rate of recurrence in young patients (less than ten years old), in active cysts, in females, and in incompletely packed cysts. However, of the cysts that were completely packed, 88 per cent healed. These data show that freeze-dried allogeneic crushed cortical bone is superior to similiarly processed cancellous bone and gives results similar to those achieved with fresh autogenous cancellous bone. Orthopaedic surgeons should therefore consider the use of freeze-dried allogeneic crushed cortical bone instead of autogenous grafts to avoid the morbidity and increased risk of complications associated with the procedure to obtain the autogenous bone.
Bioarcheologists interpret skeletal health by examining variability within and between individuals. Studies of bone loss have generated contradictory and conflicting results regarding the onset and severity of age-related bone loss on a global and temporal scale, perhaps due to mismatched methodologies. Intraskeletal comparisons of bone tissue prove challenging precisely because of heterogeneous baselines in quantity and remodeling of cortical bone throughout the skeleton, as well as evolutionary histories and environmental impacts on growth and development. Here we analyze cortical bone indicators from the rib, metacarpal, and femoral cortical bone in a subset of individuals (n = 72) regions from the medieval Italian archaeological site of Pieve di Pava. To facilitate intraskeletal comparisons across elements with different biological baselines, we standardize cortical bone parameters using z-scores. Variation in relative intraskeletal cortical bone was assessed using accessible multivariate methods (principal component analysis and hierarchical cluster analysis). Results suggest an association between femoral and metacarpal cortical bone values, with stochastic trends in metacarpal and femoral relative bone quantity in relation to the rib bone quantity at the sample level. Our study demonstrates that while intraskeletal analyses are challenging, they are made more robust by synthesizing multivariate methods alongside exploratory data analysis (EDA) methods to tack between sample-level and individual-level scales and variability. Ultimately, we advocate for leveraging multivariate techniques not as a final step, but rather as a means of generating new hypotheses and challenging tendencies to a priori establish typological groups in the research process.
Cortical bone width measurements taken at midshaft on the second metacarpal were obtained from 156 hand X-rays of 80 karyotypically documented individuals with Turner's syndrome age 1 to 25 years. Total shaft width, medullary width, cortical width and percent cortical area were grouped by bone age and compared with normal female standards. Total width was significantly and increasingly below normal; medullary width was not consistently different from normal; cortical width was significantly lower from normal from age 14 onward, although it did rise at age 17 (adult bone age); percent cortical area was significantly below normal at ages 14 and 15, but was normal by adulthood. Values for percent cortical area did not indicate severe or widespread osteoporosis. Within the Turners sample cortical bone measurement were not significantly decreased in the presence of the XO sex chromosome constitution compared with other sex chromosome variants. Nor were the measurements decreased in the presence of positive metacarpal sign or a combination of typical Turner stigmata (web neck, low posterior hairline, shield chest). There was evidence that cortical width and percent cortical area increased significantly following estrogen treatment or spontaneous menarche.
The association of stature and age with measures of second metacarpal cortical bone growth is investigated in a sample of 1586 radiographs taken from Guatemalan Ladino children aged 1-7 years in a setting of endemic mild-to-moderate malnutrition. For given stature, chronological age is positively associated with cortical thickness and cortical area and negatively associated with periosteal and medullary diameter. These different partial correlations are seen as evidence of different kinds of growth. Correlations of cortical bone variables with body size within a chronological age are shown to derive from the overall relationship between age, stature, and measures of cortical bone.
A technique is described in which the microstructure of cortical bone is analysed in terms of distributions of possible paths which ionizing particles take as they transverse the soft-tissue cavities and mineralized component. Measurements are restricted to transverse planes in the long bones, but a method is suggested for generating approximate omnidirectional path-length distributions from the measured transverse distributions. Results are presented for some long bones of a 50 year old man, a 9 year old boy and a young adult beagle, and these suggest that considerable structural differences occur between the two species. Values of some commonly quoted structural parameters are also given. For example, mean transverse cavity path lengths range between 67 and 99 micron in the long bones of the adult man compared with 29 micron in the beagle femur; the corresponding mean path lengths through the mineralized component are 830-1040 and 1500 micron. Finally, the total cavity plus periosteal surface for cortical bone in adult man is estimated to be about 6 m2.
The fate of cortical bone grafts, rigidly fixed by means of a special metal splint, was studied in rabbits. Cortical grafts of fresh autologous bone were compared with dry-stored allogenous transplants frozen to -20 degrees C. To study the incorporation and remodeling, fluorochrome labeling and microradiography were used. The main parameters of remodeling were the quantities of old lamellar bone, newly formed lamellar bone, and vascular spaces present in the transplant areas. The data obtained are compared with the results of a previous similar study of grafts, which were fixed by Mersilene sutures. Fresh autologous as well as allogenous (dry-stored, frozen to -20 degrees C) cortical bone grafts, used as free transplants, show the same type of incorporation and ultimately the same amount of remodeling. Rigid fixation is a valuable contribution in promoting primary function.
The right and left femora of three groups of rodents, cold stressed, noise stressed, and heat stressed, were sectioned transversely at the most inferior point of the third trochanter. Cortical bone thickness of the proximal section for all three groups was determined by measuring an enlargement obtained with a Wild stereo microscope with a camera lucida drawing attachment. Cold stressed animals were found to have significantly thinner cortical bone than did controls, noise stressed animals did not differ from controls, and heat stressed animals had thinner cortical bone than did controls. It is concluded that stress may be responsible for the thinner cortex of cold and heat stressed animals, but that other factors may be at work and that it is not possible to tell whether different types of stress act through the same or through different mechanisms.
The effect of rigid plate fixation on the structure and mineral content of cortical bone were studied by light and fluorescence microscopy and by chemical analysis of calcium and hydroxyproline content in 27 rabbits from one day to 17 weeks after the attachment of a 5 hole ASIF-plate onto intact femur. Between the second and seventeenth postoperative weeks the plated cortical bone became progressively thinner and porotically transformed. Subendosteal resorption was partly offset by the formation of new subperiosteal bone that resulted in a slightly wider than normal, thin-walled tubular bone. At 17 weeks the mean calcium content of the tubular bone under the plate was 15% less than the initial postoperative content (p less than 0.05). The corresponding decrease in calcium content in the metaphyseal and epiphyseal areas of both the operated and the control bone was highly significant. The mean values for hydroxyproline in plated and control bones remained largely unchanged.
Bone density and composition were studied in trabecular and cortical bone from control 2 and 4 year old beagles and those which had various degrees of renal failure as a result of perinatal irradiation. Changes in the two types of bone were qualitatively similar but consistently greater in trabecular bone. In a group identified as markedly uremic, the decrease (P less than 0.025) from control levels in specific gravity was about 4 times greater in trabecular than in cortical samples. The decrease (P less than 0.025) in grams of ash/ml was 9% in trabecular bone and 2% in cortical bone. These changes were associated with an increase (P less than 0.001) in water content and, on a percent by volume basis, approximately equal decreases in ash (P less than 0.025) and combustible matter (P less than 0.025). In a mildly uremic group there were similar trends in mean values but the only significant difference was an increase (P less than 0.001) in trabecular bone water.
From powdered bovine bone cortex an extract has been prepared with 0.15 M NaCl and its collagen-free fraction obtained on DEAE-cellulose column was used for the immunization of rabbits. The non-collagenous protein fraction (NCP) produced against immune serum two precipitation arcs both on agarose double gel-diffusion and with immune electrophoresis. After decalcination in 10% EDTA PH 7.4, direct and indirect immune histochemical examinations were performed with fresh, freshly lyophilized, as well as with bones kept for three and six months at 20 degrees C, and the antigens were localized. Prolonged storage increased the antibody-binding capacity of the bones, whereas lyophilization decreased it. Fixation in cold acetone was suited best for immunohistochemical study of the cortical bones.
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Hypophysectomy increases both periosteal resorption and endosteal apposition along the femur diaphysis in rat. Administration of alpha-MSH decreased the periosteal resorption but had no effect on the endosteal apposition. ACTH had only minor effects on the endosteum. Thus, alpha-MSH and ACTH, in the doses used, have different effects on cortical bone in rat. The effect of alpha-MSH on cortical bone could be an effect of the hormone alone or by its stimulation of other factors.
Bending properties of samples of cortical bone taken from the cranial, caudal, medial, and lateral quadrants of the midshaft of the radius, femur, and metacarpus of 12 ponies, 18 months old, were determined by 4-point loading at a rate of 10 mm/minute. The elastic modulus for all samples was between 16.2 and 20.2 GN/m2, and the ultimate breaking strength, between 204 and 255 MN/m2. There was greater variation in these properties between bone quadrants than between bones. Samples from the cranial and medial quadrants of both femur and radius were stiffer and had greater ultimate breaking strength than caudal or lateral samples. All samples of radius deformed more and absorbed more energy before reaching the greatest load than did samples of femur. The elastic modulus and the ultimate breaking strength of radius within any quadrant were highly correlated to specific gravity. However, at any specific gravity, caudal and lateral samples were not as strong as cranial and medial samples. Samples taken from exercised ponies, male ponies, or those fed diets containing 0.7% Ca,0.6% P or 2.7% Ca,1.1% P tended to be stiffer and have a greater ultimate breaking strength than samples taken from unexercised ponies, females, or those fed diets containing 0.7% Ca,1.4% P.
Calcium and hydroxyproline content of intact rabbit tibio-fibular bone was assay chemically 1 day to 36 weeks after compression and neutral plate fixation with a 4-hole stainless steel ASIF/DCP plate. During the first three postoperative weeks calcium content of the cortical bone decreased by an almost significant amount (P less than 0.05); thereafter, calcium values remained subnormal but did not differ significantly from initial postoperative values. Hydroxyproline content increased steadily throughout the experiment (P less than 0.001). The changes in chemical composition of the bone were of the same magnitude after compression and neutral plate fixation. The results suggest that the cancellous transformation of cortical bone, known to take place under rigid plates, reflects an active remodelling process of the bone in which the calcium and hydroxyproline content changes only slightly.
The cell population within and around allografts of fresh, marrow-containing cortical bone has been studied. The grafts were implanted into intramuscular sites in rats and removed at intervals over a 4 week period for examination by light and electron microscopy to establish the sequence of changes at both the tissue and cellular levels. The tissue organization and the ultrastructural appearances of the cells found at different times after grafting are described; the possible relationships of the different cell types to each other and their likely roles in both the immunological and histogenic events are postulated and discussed. A comparison of the observations in the allograft and in the previously studied autograft suggests that the cells from the granulationtissue that become osteoblasts in the autograft differentiate into fibrocytes and giant cells in the allograft. Furthermore, the increased period of initial degeneration observed in the allograft (2 weeks) compared with the autograft (less than 1 week) may represent the destruction of early, graft-derived attempts at osteogenesis. This, together with the relative paucity of new bone in the allograft, suggests that some cells of graft origin may contribute to the early osteogenesis observed in the autograft.
Two distinct groups of non-collagenous components were isolated from rat cortical bone gelatin which had previously been digested with purified bacterial collagenase. One component was disulfide-bonded, strongly acidic, trypsin-labile glycoprotein aggregate with a molecular mass of more than 100,000 daltons. When reduced with beta-mercaptoethanol this protein disaggregated into subunits with a molecular mass of about 60,000 daltons. The other components consisted of a group of polypeptides with a molecular mass of about 5,000 daltons. The latter group was present in collagenase digests prepared from normal bone gelatin but was hardly detectable or absent in digests of gelatin prepared from either autolyzed, trypsinized or lathyritic bone, or from the residue of neutral salt extracted rat tail tendon.