Abstract: Dual-photon absorptiometry with gadolinium 153 was used to measure the mineral content of lumbar vertebrae in cadavers, excised vertebrae with marrow, and dry, marrow-free vertebrae. The error introduced by the surrounding soft tissue of cadavers was 3%, and the error in determining mineral mass or density in excised vertebrae was about 5%. The correlation coefficient between the results of Gd-153 and corrected iodine 125 (single-photon) absorptiometry on 24 femoral necks was 0.99, and the predictive error was 3.7%. Dual-photon absorptiometry accurately indicates bone mass and bone density and is only slightly affected by either surrounding tissue or fat changes in bone marrow.

Abstract: Serial measurements of bone mineral in 17 ambulant female patients with rheumatoid arthritis (RA) of recent onset and 19 age matched female controls were made in the radius by computed tomography and in the vertebrae by dual photon absorptiometry. Loss of trabecular bone from the distal radius was more rapid in RA (p = 0.0014), but there was no difference in the rate of loss of bone mineral from the radial midshaft or lumbar spine compared with the controls. This study is consistent with the hypothesis that the predominant form of bone loss early in the disease is the vicinity of affected joints.

Abstract: We examined the relationships between the density of the subchondral bone of the proximal end of the tibia and the location and condition of the overlying articular cartilage and menisci. We took coronal sections of the tibial plateaus and of the overlying articular cartilage and menisci from human knee joints that were grossly free of osteoarthritis. The specimens were examined for the presence of cartilage fibrillation using the India-ink technique of Meachim. Bone density was determined using the Quantimet picture-point analyzer. Fibrillation of articular cartilage was observed only in the articular cartilage that was not covered by meniscus and lying mesial to it, which supports the concept that the meniscus confers a protective effect on the articular cartilage. The density of the bone underlying the meniscus was lower, and was inversely related to the thickness of the meniscus and directly related to the thickness of the articular cartilage. In four knees from which the menisci were absent, the bone density was increased at the periphery. We suggest that there is a trinitarian relationship between the meniscus, cartilage, and subchondral bone, in which structural changes in any one of the three causes secondary pathological adaptive changes in the other two.

Abstract: Two different dual-energy projection radiography techniques were utilized in an attempt to predict femoral neck strength, bone density, and bone mineral content in 19 pairs of cadaver specimens. Positive simple linear correlation was observed between dual-energy scanned projection measurements and dry density, ash fraction, cross-sectional cortical bone area and, to a lesser degree, force required for fracture, but not trabecular bone volume, failure time, or Singh trabecular grade. Dual-energy film radiography was found to be a less reliable indicator of femoral neck strength, density, and mineral content. Dual-energy scanned projection results related linearly to mineral-equivalent solution (K2HPO4) concentration, and demonstrated long-term reproducibility in repeated specimen studies. Correction factors derived to account for differences in femoral size and rotation were shown to be reliable over a moderate range of neck projections. Although bone mineral measurement at other sites may provide comparable or greater information concerning hip fracture risk, dual-energy scanned projection radiography appears to be a useful technique for assessment of bone density, mineral content, and strength in the femoral neck.

Abstract: This paper presents an image enhancement and analysis system (DARWIN) based on an inexpensive microcomputer and applies the system to two bone morphometry problems relevant to postmenopausal osteoporosis. Using ovariectomized and intact female Macaca fascicularis as a model, we examined the radiodensity of the sixth lumbar vertebra and the cross-section area of the right femur. Significantly lower bone density was observed in the vertebral segments of the ovariectomized animals. No significant differences were observed in comparisons of the femoral cross sections. The reduction in radiographic density of the ovariectomized animals' vertebrae is similar to that observed in postmenopausal women, supporting the use of female cynomolgus macaques as models of bone loss in postmenopausal osteoporosis.

Abstract: Bone density in the lumbar spine and distal radius of 98 postmenopausal women was measured by quantitative computed tomography and in the distal radius by gamma ray attenuation. Nineteen had spinal fragility fractures, 30 had recent hip fractures while 49 were healthy control subjects. The trabecular bone density in spines of the control subjects showed a linear correlation with age corresponding to an annual decrease of 1 per cent and total decrease of 44 per cent between 46 and 86 years of age. Both patient groups had bone density reduction at the spine and peripheral measuring sites as compared with controls. In the distal radius, the reduction in bone density was of the same magnitude in both patients groups but in the spine, the reduction in patients with spinal fracture was more extensive than that in patients with hip fracture. Trabecular bone density in the distal radius and spine correlated in control and hip fracture patients, but not in spinal fracture patients. The results support the opinion that two forms of osteoporosis exist. One is characterised by excessive trabecular bone loss in the axial skeleton leading to spinal fractures; the second is due to equal extents of axial and peripheral osteopenia, found in connection with hip fractures.

Abstract: Radiologic measurements of cortical thickness of the radius and second metacarpal were used to determine bone density in postmenopausal North American Indian (N=34) and Caucasian (N=43) women. The ratio of cortical area to total crosssectional area was calculated. The mean cortical area ratios, adjusted for number of years postmenopause, were significantly lower in Indian women for both the radius (.60) and metacarpal (.69) compared with Caucasian women (.66 and .76 respectively). Using stepwise multiple regression analysis, the body mass index (kg/m2) and number of years since menopause were identified as significant predictors of radial bone density in Indians. Body mass index was also the most important determinant of metacarpal bone density in Indian women and, contrary to expectations, smoking had a positive effect. Among Caucasian women, both radial and metacarpal bone density decreased with increasing number of years since menopause and with cigarette smoking. Chronologic age, age at menopause, activity level, frequency of consumption of high-calcium foods, and presence or absence of diabetes were not significant predictors of cortical area ratios in either group. The findings from this preliminary study suggest that postmenopausal bone loss may be highly prevalent among American Indians as well as Caucasians. Postmenopausal bone loss is a major cause of morbidity in elderly women. A number of factors play a role in the maintenance or loss of bone mass. Thin women are more susceptible to osteoporosis than heavy women (Daniell, 1976; Meema et al. 1973). Smoking (Daniell, 1976) and inactivity (Aloia et al. 1978; Heaney et al. 1982) are reported to adversely affect bone mass. Women with non-insulin dependent diabetes may also be at risk for bone loss (Levin et al. 1976; Paganini-Hill et al. 1981), although other investigators have noted greater cortical bone mass in diabetics (Meema and Meema, 1967; De Leeuw and Abs, 1977). Finally, calcium deficiency has been associated with bone loss in postmenopausal women (Nordin et al. 1979; Heaney et al. 1982). Our purpose was to determine if the risk factors for bone loss previously identified for Caucasian women are operative for Indian women. department of Family Medicine, University of Western Ontario, London, Ontario, Canada, N6A 5C1. 2Department of Radiology, University of Western Ontario, London, Ontario, Canada, N6A 5C1. Human Biology, December 1985 , Vol. 57, No. 4, pp. 719-726. © Wayne State University Press, 1985 This content downloaded from 40.77.167.44 on Tue, 26 Jul 2016 06:20:02 UTC All use subject to http://about.jstor.org/terms 720 Susan E. Evers, John W. Orchard and Richard G. Haddad To our knowledge, bone density has not been measured in Canadian Indians. The prevalence of obesity in Indian women is much higher compared to Caucasians (Nutrition Canada, 1975; Evers and Rand, 1984). Non-insulin dependent diabetes is common among North American Indians (West, 1978). In addition, Canadian Indians reportedly have a low intake of calcium (Nutrition Canada, 1975). Materials and Methods Subjects were postmenopausal women aged 45 years and over who attended a family medical center in Southwestern Ontario. The catchment area for the center includes the Caradoc Reserve and Oneida Settlement (Indians of the Oneida, Chippewa and Muncey bands), and two rural towns. Thirty-four Indian and 43 Caucasian women were enrolled in the study. The subjects had their weights and heights measured and were interviewed to obtain the following information: birthdate, smoking status (smoker or non-smoker), age at menopause, usual level of physical activity, frequency of consumption of calcium-rich foods, and presence or absence of diabetes. For purposes of this study, subjects were considered diabetic if they reported a history of diabetes and were under treatment as indicated on their medical records. The body mass index (weight in kilogram s /height in metres squared) was used as an indicator of obesity (Khosla and Lowe, 1967; Criqui et al. 1982). Activity level was rated high for subjects who stated that they exercised for at least 20 minutes daily or two to three times a week. Subjects who responded not often or never to the activity question had a low activity level. Similarly, subjects who reported that they had a minimum of one serving a day of a calcium-rich food (milk, yoghurt, ice cream, cheddar or processed cheese) were rated high for consumption of calcium-containing foods. Women who did not have at least one daily serving of a food high in calcium were ranked low in calcium consumption. After the interview was completed, radiographs of the hand and proximal radius were taken for subsequent measurement of the cortical thickness of the second metacarpal and the radius. These measures provide an estimate of cortical bone loss in the non-weight-bearing appendicular skeleton. All measurements were made by R.G.H. as described below. Posterior-anterior radiographs of the hand were taken using industrial film at 100 cm tube-film distance as described by Meema and Meema (1976). The length of the second metacarpal was measured in millimeters with a ruler. At the midpoint of the second metacarpal, the external width This content downloaded from 40.77.167.44 on Tue, 26 Jul 2016 06:20:02 UTC All use subject to http://about.jstor.org/terms Bone Density in Postmenopausal Women 721 (W) and the width of the marrow cavity (m) were measured with a caliper. The distance between caliper points was read to 0. 1 mm using a measuring magnifier. Using these measurements, the ratio of cortical area to total cross-sectional area was calculated: (W2m2)/W2, where W = external width measured in millimeters and m = width of the marrow cavity in millimeters. The cortical area ratio records the relative amount of cortical bone in the skeleton correcting for differences in skeletal size (Solomon, 1979). Lateral radiographs of the proximal radius were obtained in a similar fashion. To facilitate the measurements for calculation of the cortical thickness, a distance of two and one-half times the diameter of the radial head was measured from the capitulum humeri distally and marked (Meema and Meema, 1976). The cortical area ratio was calculated as described above. Standard statistical techniques were used in the analysis of the data, including the t-test for comparison of means in independent samples. Analyses of covariance were conducted on the cortical area ratios with number of years since menopause as the covariate. The data were further analyzed using multiple regression with bone density (represented by the area ratio) as the dependent variable and number of years since menopause, body mass index, frequency of consumption of high calcium foods, smoking status, activity level and presence or absence of diabetes (for Indians only) as the independent variables (Nie et al. 1975).

Abstract: Calcium loss experience by astronauts under weightless conditions is discussed. I-125 photon absorption measurements on astronauts on the Apollo 14, 15, and 16 flights showed bone density decreases of 6.6 percent in one astronaut and 7.3 percent in another. The estimated total body calcium loss on Apollo 17 was 0.2 percent. The test results indicate that calcium losses occur mainly from the weight-bearing parts of the skeleton. Measures to counteract the losses include 'penguin' suits, maintenance of nutrient intakes at high levels, and extensive exercise on ergometer and treadmill.

Abstract: Bone density (BD) at the distal end of the radius was measured serially with gamma-ray computed tomography (γ-CT) in five groups of healthy postmenopausal women. One group comprised untreated controls; women in the other groups were subjected to pharmacologic challenge with putative activators and/or depressors of bone remodeling. The challenge agents, taken orally, were ergocalciferol (vitamin D2) alone and followed by calcium; calcitriol (1,25 OH)2D3), and prednisone. All of the subjects showed changes in BD following challenge; these changes were significant (P<0.05) for the groups receiving vitamin D2 and vitamin D2 plus calcium. Responses to ergocalciferol, calcitriol, and prednisone were similar within groups, whereas the group receiving ergocalciferol then calcium comprised two distinct subgroups: bone density transiently increased in one and decreased in the other. For all five groups, the direction of change in bone density in response to the challenge, and its duration and magnitude, were consistent with reported histomorphometric data. We conclude that γ-CT assessment of change in bone density after pharmacologic challenge provides a useful noninvasive approach to skeletal investigation.

Abstract: The search for a specific level of bone density that clearly distinguishes patients with osteoporosis from those without has been largely unsuccessful. A different, ''gradient of risk'' model was used to assess the effect of various degrees of osteoporosis on the prevalence of vertebral fractures. The authors measured spinal (L/sub 1/-L/sub 4/) bone mineral (BM) with dual photon absorptiometry in an age-stratified random sample of Rochester, Minnesota women greater than or equal to 35 years old to estimate the distribution of spinal BM in the population of adult woman. The authors also assessed BM among women in the sample who had one or more vertebral fractures to estimate both the total number of women with vertebral fractures in the population and the distribution of spinal BM in such women. These population-based estimates were then used to calculate the prevalence rate of vertebral fracture at various levels of spinal BM. Women with spinal BM greater than or equal to 1.40 g/cm/sup 2/ were free of vertebral fractures. Among women with BM between 1.00 and 1.39 g/cm/sup 2/, the prevalence of vertebral fractures was about 7%. The prevalence rate increased as spinal BM decreased further. Among women with spinal BM<0.60 g/cm/sup 2/,more » all had at least one vertebral fracture (prevalence=100%). These data indicate that osteoporosis is a necessary cause of age-related vertebral fractures and, at certain low levels, is a sufficient cause of such fractures in conjunction with the activities of daily living.« less

Abstract: Computerized tomography (CT) provides the capability to determine vertebral bone density with a high degree of accuracy and precision, detecting density changes as small as 5% in serial testing. In this pilot study, CT was used to determine the effects of total hip arthroplasty and its consequent alterations in physical activity levels on the vertebral bone density of 13 postoperative patients. Vertebral bone density was also evaluated in six preoperative patients with degenerative joint disease of the hip and five control patients. The preoperative group and controls were then compared with the postoperative patients, who were divided into two groups--those who had achieved good activity levels and those whose levels of activity remained poor. CT measurement of bone density in the central bodies of T12, L1, and L2 showed that the preoperative group was similar to controls. This suggests that patients accept total hip arthroplasty rather than endure significant activity limitations for extended periods of time. When activity level was restored by arthroplasty, vertebral bone density was preserved. If the patient continued at a poor activity level postoperation, significant loss of bone density occurred secondary to disuse.

Abstract: The skeletal dysplasias are constitutional, generalized or localized disorders of the skeletal system involving a disturbance of growth and/or bone density; their genetic transmission varies. Pathomorphologically, a combined functional-structural disturbance of the cartilaginous and/or bone tissue is present. Clinically, the result is varying degrees of dwarfism.

Abstract: Bone loss after internal fixation is assumed to be the cause of refracture after e.g. plate removal. The scatter of reported refracture rate and the limited data available on quantitative changes in the human have triggered the study o radiological bone density using computed tomography. 30 patients were assessed on both legs at the level of the fracture. The average bone loss was offset by an increase in the total area of bone. 1/3 of the fractures had healed radiolog ically “per primam”. Here the data from the intact side and the fracture side was of similar geometry but reduced density for the fractured side. The mechanical effect of the bone loss seems to be small.

Abstract: Dual radionuclide imaging of the neck (Tc-99m pertechnetate and TI-201 thallous chloride) was performed in 22 patients with chemical evidence of hyperparathyroidism (elevated blood calcium and parathormone [PTH] levels). Of these, 19 of 22 had localization of a TI-201 "excess" area on radiothallium-radiotechnetium subtraction images. In 13 patients who have had operative confirmation at this writing, the dual radionuclide imaging was positive in 12 (12/13 = 92.3%). One patient had two parathyroid adenomas, both of which were seen on the images; thus, overall detection was 13 out of 14 or 92.8%. The parathyroid adenomas visualized weighed from 0.06 to 3.0 g; the one not detected weighed 0.25 g. In three patients with parathyroid hyperplasia secondary to renal disease, the subtraction imaging detected eight of 12 glands (66.7%). The forearm bone mineral content and bone density were determined in eight patients with parathyroid adenomas; results were abnormally low in five of these eight. One of the three patients with secondary hyperparathyroidism had an abnormally low radial bone mass. The combination of dual radionuclide imaging and radial bone mass determination may present a useful approach in both localizing abnormal parathyroid tissue and in examining its functional consequences.

Abstract: Sequential measurements of the density of calcaneal trabecular bone were made in normal postmenopausal women and in patients treated for osteoporosis. Cross-sectional measurements of density were made in previously normal patients who had been without ovarian function for a known length of time of at least one year. There was a significant reduction in calcaneal density associated with aging in normal postmenopausal women. Estrogen lack was also associated with density reductions and the reduction was related to the length of time of estrogen deprivation. When osteoporotic patients were treated with combination therapy, density rose in females while in males the expected age dependent reduction was prevented. It is concluded that photon scattering measurements of calcaneal density can be used to monitor changes in the mineral status of the skeleton.

Abstract: The histomorphometric analysis of a non-decalcified trans-iliac bone biopsy allows the bone mass to be evaluated histologically and, more especially, enables the bone mass to be divided into its cortical and trabecular compartments. The parameters usually measured are the trabecular bone volume (TBV), the total bone density and the cortical thickness. The inter-sample variation for the TBV can be as high as 29 per cent for a given osteoporotic subject, but is only 10 per cent and 7 per cent respectively for groups of 10 and 20 subjects. This variation can be considered to be significant in larger groups with successive biopsies. There is a physiological bone loss with age, but the intensity and the profile of this decrease in the TBV is different in men and women. In cases of osteoporosis with vertebral compression, the TBV appears to be the most discriminating parameter between osteoporotic subjects and controls of the same age and sex and was always found to be less than 16 per cent in a series of 154 osteoporotic patients with at least one vertebral compression. Apart from the evaluation of the quantity of bone present, histomorphometry also allows trabecular osteoporosis to be differentiated from cortical osteoporosis and allows a histological definition of the type of osteoporosis in terms of the parameters reflecting bone remodelling (area of resorption, number of osteoclasts, area of osteoid osteoblastic apposition rate, etc...).

Abstract: those patients with a final diagnosis of normality were investigated. Some ambiguities arise from the definitions given for the risk groups-for example, it is not clear to which risk group a patient with a probability of duodenal ulcer of 0-89 and a probability of gastric cancer of 0 11 should be allocated, nor is it clear exactly what \"predicted as having an ulcer\" means. In referring to the system of Mann et al the authors' statement, \"In those (patients from general practitioners' surgeries] who did score more than 8 the incidence of serious disease was only slightly higher (1%),\" is incorrect. From table II this proportion should be 260%, (34/131 patients), and this is significantly higher (p< 005) than the proportion of cases with serious disease scoring 8 or less.

Abstract: The assessment of bone status is so far usually performed by means of the relatively simple methods of radiographs and radiogrammetry, which are not always able to give a correct information about bone mineral content (B.M.C.) especially in cases of cortical osteoporosis. Among the other non-invasive methods, single- and dual-photon absorptiometry are of particular interest for their relatively low cost, precision, accuracy and repetitibility, giving the patient a very slight dose of radioactivity. Dual-photon device, in particular, offers the possibility to investigate B.M.C. in the bones surrounded with large amount of tissue, even in obese people. To assess bone status of feminine population, we have analyzed 238 patients, divided into 3 groups (normal pre- and post-menopausal women, and osteoporotic) measuring their radius and lumbar spine B.M.C. with single- and dual-photon absorptiometry. As a result, B.M.C. of both measuring sites appears closely correlated with age, and with the duration of menopause. In our group, cortical bone density showed a postmenopausal rate of loss higher than the trabecular. Vertebral measurements, too, were more closely correlated with age when corrected for body surface area. Osteoporotic group showed a B.M.C. significantly lower than the age-matched group of normal women both in spine and in radius: in conclusion, all these findings stress the importance of a widespread population surveillance in order to individuate and treat the patients at risk of spontaneous fractures.

Abstract: Octeocalcin (OC) a calcium binding protein of bone matrix, appears to play a role in the regulation of mineral deposition and remodeling of bone. Elevated plasma levels of OC have been reported in some metabolic bone diseases with high bone turnover. We have reported an increase in bone turnover in osteogenesis imperfecta (01). Plasma OC and serum Ca, P, Alkaline phosphatase concentrations drawn at 8-9 am were studied in 17 untreated 01 patients (Ages 0.6-11 y;), and 22 normal controls (Ages 2-9 y.). OC was measured by RIA using rabbit-antiserum to bovine OC and purified bovine OC. Osteoporosis was quantitated by measurements of bone density using the method of radiographic photodensitometry, and compared to age and sex-matched normals. OC plasma levels in 01 were 81.6±34.3 mean ± SD compared to 25.0±12.5 ng/ml in control subjects. The difference is significant at p<0.001. Bone density, normalized for age and sex was significantly correlated to plasma OC concentrations, r=0.49, p<0.05, but it did not correlate with serum alkaline phosphatase levels. The elevated plasma levels of OC in OI is the first reported biochemical index to correlate with the severity of osteoporosis in OI.