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PubMed1989

Radial and vertebral bone density in white and black women: evidence for racial differences in premenopausal bone homeostasis.

The reasons for a different incidence of osteoporotic fractures in white and black women are unknown. Previous racial comparisons of bone mass have been limited by racial differences in body weight and socioeconomic, health, and nutritional status. This cross-sectional study examined bone density in 105 black and 114 white healthy nonobese women, 24-65 yr old, using dual photon absorptiometry of the lumbar spine and single photon absorptiometry of the distal radius. Bone density at both sites was higher in blacks at all ages than in whites. When adjusted for age and body mass index, mean bone density was 6.5% higher in blacks at both spine and radius (P less than 0.0001). The cross-sectional rate of decline of vertebral bone density was similar between races; however, radial density increased 3.8%/decade (P = 0.03) in premenopausal blacks under age 46 yr, while it declined 3.2%/decade (P = 0.09) in premenopausal whites. The racial difference in slopes in these premenopausal women is significant (P = 0.002). These findings suggest that attainment of higher peak bone mass and delayed onset of bone loss contribute to the lower incidence of osteoporotic fractures in black women.

Adult↗

PubMed1991

[The effect of conservative and surgical management for secondary hyperparathyroidism and their problems].

We compared the effect of conservative treatment with that of surgical treatment after applying them on secondary hyperparathyroidism patients (2nd HPT) in order to study the application of surgery on 2nd HPT patients. We selected the test subject of 39 maintenance dialysis patients with complications of 2nd HPT. The conservative treatments were; elcitonine administration (40 u x 3/W) (group 1), ipriflavon administration (200 mg x 3/day) (group 2), and pulse treatment (1.25 (OH)2D3 6 micrograms/W) (group 3). For surgical treatment, we adopted total parathyroidectomy with auto-transplantation into the arm (PTX). The transition of serum parathyroid hormone (PTH-C), alkali-phosphatase (ALP), bone scintigraphy of every 6 months, and change of bone mineral content (BMC) were compared to judge the effects of treatments. We measured 1/3, 1/6 radial region with single photon absorptiometry (SPA) and L3 region with dual photon absorptiometry (DPA) to obtain BMC. We were forced to transfer the patients in groups 1 and 2 (conservative treatment) to pulse treatment or PTX as 12 months later they showed increase in serum PTH-C, ALP and significant drop (P less than 0.05) in BMC average change rate (1/3). In group 3 of pulse treatment, though significant decrease in serum ALP (P less than 0.01) was detected for 10 cases out of 12, serum PTH-C was either unchanged or increased for 4 cases with the value of more than 30 ng/ml. Furthermore the average change rate of BMC stayed at the same level.(ABSTRACT TRUNCATED AT 250 WORDS)

24,25-Dihydroxyvitamin D 3↗

PubMed1990

Heparin effect on bone density.

In order to provide estimates of the risks of symptomatic osteoporosis and reduced bone density in premenopausal women treated with long-term (greater than 1 month) heparin therapy, we evaluated a cohort of 61 consecutive premenopausal women previously treated with long-term heparin (cases) and a group of controls matched for age, parity and duration between the last pregnancy and evaluation. All patients underwent dual photon absorptiometry of the lumbar spine and single photon absorptiometry of the wrist and most cases underwent plain lateral radiography of the thoracolumbar spine in order to exclude silent fractures. Although none of the cases suffered symptomatic fractures (0 of 61, 95% confidence intervals 0.0 to 5.9%), there was a significantly greater proportion of cases than controls with bone density below our pre-defined levels. The long-term implications of our findings are uncertain but because it is possible that the reduction in bone density predisposes women to fractures, this potential risk should be considered when treating women with long-term heparin.

Adult↗

PubMed1987

Dual-photon bone densitometry in normal Australian women: a cross-sectional study.

Osteoporosis is a major health problem in Australia, as it is in most Western societies. Bone mineral density in the spine and femoral neck are accurate indicators of osteopenia and thus useful indicators of the risk of a fracture. Dual-photon absorptiometry is a non-invasive technique that allows the accurate quantitation of bone mineral density in the lumbar vertebrae and proximal femur with a low radiation exposure. The increasing availability of this technique dictates the requirement for "normal" ranges and quality control. We report here lumbar vertebral and proximal femur bone mineral density as measured by dual-photon absorptiometry in 179 normal Australian women. Forearm bone mineral content in these subjects, as measured by single-photon absorptiometry, is also presented. There was a relative stability of lumbar bone mineral density and forearm bone mineral content before the menopause, after which there was an age-related decline. On the other hand, bone mineral density at all three sites in the proximal femur showed an age-related decline throughout adult life. Intraoperator variability in calculated bone mineral density did not exceed 2.3%. The requirement for correct positioning of the patient is illustrated. The data allow statistical analysis and the development of normal ranges. They provide an Australian base against which individual patient values can now be compared.

Adult↗

PubMed1996

Bone mineral and related biochemical variables in patients with Kock ileal reservoir or Bricker conduit for urinary diversion.

PURPOSE: Bone material content was studied with single photon absorptiometry and dual energy x-ray absorptiometry , and the various biochemical parameters related to bone metabolism in patients with Kock reservoirs or Bricker conduits for urinary diversion. MATERIALS AND METHODS: We examined 34 patients with Kock ileal reservoirs to the skin (29) or urethra (5) and 14 with Bricker conduits 2 to 17 years after urinary diversion. Bone mineral density was measured in the radius with single photon absorptiometry, and in th femur, lumbar spine and whole body with dual x-ray absorptiometry. Serum concentrations of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, osteocalcin, parathyroid hormone, bone specific alkaline phosphatase and ionized calcium were determined. Arterial blood gases were analyzed. RESULTS: The mean values for bone mineral density did not differ from age-matched controls in either group and no signs of decrease were observed with followup. Vitamin D serum concentration values remained within normal limits in all patients. Most patients had normal blood gas values. Mean values for osteocalcin, parathyroid hormone, bone specific alkaline phosphatase and ionized calcium also were within normal limits, although a few patients had elevated osteocalcin values indicating increased bone turnover. CONCLUSION: Urinary diversion with a Kock reservoir or Bricker conduit did not cause bone demineralization of significant changes in different markers of bone metabolism in patients examined 2 to 17 years after urinary diversion.

Absorptiometry, Photon↗

PubMed1991

Non-linear increase in vertebral density induced by a synthetic steroid (Org OD 14) in women with established osteoporosis.

The results of a 2-year placebo-controlled study in 38 female patients with osteoporosis are presented. This study was conducted to evaluate the efficacy of a daily oral dose of 2.5 mg Org OD 14 ((7 alpha, 17 alpha)-17-hydroxy-7-methyl-19-norpregn-5(10)-en-20-yn-3-one) in the treatment of established osteoporosis. Org OD 14 is a steroid which shows combined weak oestrogenic, androgenic and progestational activity. A total of 31 patients completed a 12-month study period (17 placebo, 14 Org OD 14) and 25 of these went on to complete the full 24-months (15 placebo, 10 Org OD 14). A significant increase in bone mineral density as measured by dual photon absorptiometry was recorded in the lumbar spine in the Org OD 14-treated patients at 8, 16 and 24 months. The gain in bone mass after 8 months averaged 4% (P less than 0.01) and after 24 months 8% (P less than 0.001). In the control group, a bone loss rate of 2% per year was recorded in the lumbar spine. No significant changes in bone density in the forearm as assessed by single photon absorptiometry were found in either group. The increase in spinal bone density in the Org OD 14 group was non-linear and followed an S-shaped upward pattern. Org OD 14, while inducing no appreciable endometrial stimulation, was found to be a bone-active compound with anti-resorbing as well as anabolic activity. Org OD 14 warrants consideration not only for the long-term prevention of bone loss but also for curative treatment of post-menopausal osteoporosis.

Absorptiometry, Photon↗

PubMed1991

Bone growth and mineralisation in children aged 4 to 10 years.

The relationships between bone width and mineral content and age, sex, height and weight were studied in 420 children aged 4-10 years living in Cambridge using single photon absorptiometry. The relationship of bone width with bone mineral content was significantly different between the sexes after adjusting for differences in body size. In addition, bone width in boys was found to be greater for a given height and weight; changes in weight had a greater effect on bone width in boys than in girls. Prediction equations for bone width and mineral content based on height and weight are given, which should enhance the application of single photon absorptiometry in clinical practice.

Absorptiometry, Photon↗

PubMed1992

Morphometric and physical investigations of segmental cortical bone autografts and allografts in canine ulnar defects.

Cortical bone grafts were implanted for six months in mature dogs using an osteoperiosteal 3-cm defect in the ulna to evaluate their respective morphometric and physical values compared with autografts. The bone-grafting material included fresh auto- and allografts, frozen and thimerosal preserved allografts, and partially demineralized bone allografts. The grafts were evaluated by roentgenograms, microradiograms, photon absorptiometry, porosity, fluorescence labeling measurements, and torsional loading at failure. Autografts achieved a better union score than the allografts, but intracortical bone porosity, percentage of cumulative new bone, and mineral apposition rate were not variables with statistical significance. Lamellar bone was found earlier and in greater quantity in autografts. Within the graft, new bone was deposited at a slower rate than in the recipient bone. Autografts showed less peripheral resorption and a greater torsional resistance than allografts. Photon absorptiometry demonstrated that nondemineralized allografts underwent a substantial loss of peripheral bone. This marked reduction in the outer diameter of the graft had more influence on torsional resistance than did the intracortical porosity of the graft. Demineralized allografts were osteoinductive in only 28% of the cases and appeared to respond in an all-or-nothing pattern. Frozen and thimerosal preserved allografts were the most acceptable substitutes to autografts.

Absorptiometry, Photon↗

PubMed1992

Bone mineral status in growth hormone-deficient males with isolated and multiple pituitary deficiencies of childhood onset.

In order to determine whether growth hormone (GH) deficiency of childhood onset affects the adult bone mineral status, we assessed bone mineral content (BMC) by photon absorptiometry in 30 full-grown GH-deficient men (8 with isolated GH deficiency and 22 with multiple pituitary deficiencies; 28 previously treated with GH) and in 30 male controls matched for age (within 4 yr) and height (within 10 cm). Forearm BMC was measured by single photon absorptiometry just proximally of the distal one third of the nondominant forearm (PBMC-2 in arbitrary units and PBMC/bone width (BW) after normalization for bone width) and at a more distal site, close to the carpal joint (DBMC-2 and DBMC/BW). Lumbar BMC was measured by dual photon absorptiometry and reported as total BMC for L2-L4 (LBMC in g) and after normalization for projected area (LBMD in g/cm2). The patients had a significantly lower BMC, both at the forearm (P less than 0.0001) and at the lumbar spine (P less than 0.005): 35.7 +/- 1.0 vs. 50.0 +/- 1.6 and 36.9 +/- 1.2 vs. 52.8 +/- 1.9 (mean +/- SEM) for PBMC-2 and DBMC-2 in patients and controls, respectively; 1.36 +/- 0.03 vs. 1.70 +/- 0.04 and 1.07 +/- 0.03 vs. 1.35 +/- 0.04 for PBMC/BW and DBMC/BW; 34.00 +/- 1.08 vs. 42.02 +/- 1.27 g for LBMC and 0.886 +/- 0.016 vs. 0.976 +/- 0.018 g/cm2 for LBMD. Both the patients with isolated GH deficiency and the patients with multiple pituitary deficiencies were osteopenic when compared to their respective controls (P less than 0.01 to P less than 0.0001 for the patients with multiple deficiencies; statistical significance reached for PBMC-2, DBMC-2, and DBMC/BW only, P less than 0.05, in the small group of patients with isolated GH deficiency). For the patients (n = 19) who had at least three serial measurements over a period of 6 to 28 months, no decrease in BMC was detected. Our findings indicate that men with GH deficiency of childhood onset present with a low adult bone mass, despite prior GH substitution in most of these subjects. The observations of a more pronounced bone mineral deficit at the forearm (20-30% lower mean values, depending on the type of measurements) than at the lumbar spine (9-19%) and the findings of osteopenia in both the patients with isolated GH deficiency and multiple pituitary deficiencies, support the view that GH deficiency per se is responsible for part of the observed deficit.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗

PubMed1990

Impact of bone mineral measurements on osteoporosis.

Dual photon absorptiometry enables measurement of bone mineral to be carried out at the clinically relevant sites of the spine and femur. Few would argue that it provides a powerful research tool, but defining its role in clinical practice has been somewhat more difficult. With the advent of X-ray based systems, studies can be rapidly carried out with improved precision, which has led to increased clinical interest. It is probable that this technology will be incorporated into routine use in the near future. In the present review we have addressed the role of dual photon absorptiometry in areas pertinent to osteoporosis and the direction in which recent developments are leading with regard to future research.

Absorptiometry, Photon↗

PubMed1992

The effect of high-intensity trunk exercise on bone mineral density of postmenopausal women.

The purpose of this study was to determine the effect of a 1-year trunk resistive exercise program on bone mineral density at the lumbar spine and hip in postmenopausal women. Forty-nine subjects were divided into exercise and control groups. Dual photon absorptiometry was used to measure bone mineral density and the Muscle Examination and Exercise Dosimeter 3000 system was used to assess trunk muscle strength. Resistive exercise target levels for the exercise group were based on the results of the trunk muscle strength tests. The exercise group performed 3 sets of 10 repetitions for each of the sit-up, prone trunk extension, and double leg flexion exercises. The subjects were seen once per month and performed the exercises a minimum of three times per week. The bone mineral density and strength tests were done at baseline, at 6 months and at 12 months. The results of the study showed that 1) the dual photon absorptiometry method and the Muscle Examination and Exercise Dosimeter 3000 system were highly reliable in measuring bone mineral density and trunk muscle strength, respectively; and 2) no significant differences were found between the exercise and control groups at lumbar vertebrae L2, L3, L4, L2-L4, and the femoral neck, Ward's triangle, and trochanteric region of the proximal femur at baseline, 6-month, and 12-month evaluation sessions.

Absorptiometry, Photon↗

PubMed1996

Effects of spaceflight on bone mineralization in the rhesus monkey.

We combined dual-photon absorptiometry, iliac crest histomorphometry, and backscattered electrons analysis to characterize bone mineralization effects of a spaceflight on young monkeys. Two 4- to 5-kg male rhesus monkeys (Macaca mulatta) were flown during a 11.5-day spaceflight that took place onboard Cosmos 2229 biosatellite (Bion 10). Vivarium (n = 4) and Earth-based chair (n = 4) control situations were studied for comparison. Flight monkeys exhibited lower values of iliac cancellous bone volume, associated with nonsignificantly thinner trabeculae. Bone mineralization rate and the proportion of trabecular bone surface involved in mineralization processes were found markedly reduced after spaceflight. Analysis of embedded sections by backscattered electrons imaging showed a nonsignificant shift to lower mineralization in the flight biopsies vs. postflight mock-up biopsies. These results were in accordance with dual-photon absorptiometry evaluations showing a tendency for decreased bone mineral content during flight and recovery thereafter. The ground simulation experiment performed on the same monkeys more than 1 mo after landing suggests that the observed effects were specifically related to spaceflight and that the animals had only partially recovered. Additional animals on future flights will be required to confirm these findings.

Absorptiometry, Photon↗

PubMed1988

Quantification of osteopenia in hip fracture patients.

Osteopenia was assessed in 56 consecutive hip fracture patients by using dual photon absorptiometry of the lumbar spine and uninjured, contralateral femoral neck and by performing iliac crest biopsy. Of the 56 patients, 47 were female and 9 were male. The mean age was 78 years. There were 31 femoral neck and 25 intertrochanteric fractures. Two comparison populations were also studied. Population 1 consisted of 269 postmenopausal females older than 60 years of age with no history of fracture who were referred for dual photon absorptiometry of the lumbar spine as screening for osteoporosis. Population 2 included 94 patients with vertebral compression fractures who underwent transilial biopsy to evaluate osteoporosis. All transilial biopsies were assessed with the use of quantitative histomorphometry. Dual photon absorptiometry of the lumbar spine indicated that 76.9% of the hip fracture patients had severe bone loss (less than 1 gm/cm2). Nevertheless, no difference in spinal bone density was found when the hip fracture patients were compared to population 1. No difference in density of the lumbar spine or femoral neck was found in patients in the hip fracture group when intertrochanteric and femoral neck fractures were compared. No difference in histomorphometric measurements of total bone, cortical bone, and cancellous bone volume was noted between the hip fracture patients and population 2. There was no difference noted when the intertrochanteric and femoral neck fracture patients were compared. No evidence of osteomalacia was noted in any group.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1991

Calcium-deficient diet in ovariectomized dogs limits the effects of 17 beta-estradiol and nandrolone decanoate on bone.

Postmortem measurements by dual-photon absorptiometry of the femur and the second lumbar vertebra in adult dogs indicated bone loss after ovariectomy, which was more pronounced when calcium-deficient diet was given in ovariectomized dogs. This bone loss was nonhomogeneous throughout the femur. Ovariectomy resulted in trabecular and cortical bone loss, and additional calcium-deficient diet resulted in a further highly significant trabecular bone loss at the proximal epiphysis of the femur and in the vertebra. This bone loss was presumably the result of increased bone turnover, as reflected by the highly significant increase in serum alkaline phosphatase. Estrogens could only partially prevent the bone loss induced by calcium deficiency after ovariectomy, and nandrolone decanoate was not effective. We conclude that (1) ovariectomy results in bone loss in adult dogs, (2) this bone loss is more pronounced after calcium-deficient diet, (3) calcium deficiency could be a limiting factor for the preventive effect of estrogens and nandrolone decanoate, and (4) dual-photon absorptiometry allows the evaluation of nonhomogeneous bone loss throughout excised bones.

Absorptiometry, Photon↗

PubMedDate not supplied

Assessment of bone mineral content and bone mass by non-invasive radiologic methods.

Methods for quantitative determination of bone mineral and bone mass in normal subjects and in patients with metabolic bone disorders can be measured by the Compton scattering technique, the neutron activation analysis, by measurement of metacarpal bone mass, by single and dual photon absorptiometry, and by quantitative computed tomography. Measurement on metacarpal bone (radiogrammetry) seems to be able to distinguish between resorption and/or new bone formation at the periosteal and/or endosteal surface. The intraindividual observer variation on combined cortical thickness (D-d), cortical area (D2-d2), metacarpal bone mass (D2-d2)/D2-varies from 0.7 to 2.5 per cent and the interindividual observer variation from 1.0 to 5.8 per cent. Single photon absorptiometry measures bone mineral content in the forearm with great precision. The reproducibility using repeated measurements and automatic selection of the measuring area is about one per cent and can be used to follow changes in mineral content with time in patients with metabolic bone diseases. The dual photon absorptiometry may be used for measurements of bone mineral content in lumbar spine, in the femoral neck and measurement of total body calcium with an accuracy of less than 6 per cent and a precision below 3 per cent. Quantitative computed tomography has the ability to measure trabecular and cortical bone both centrally and peripherally. Using CT scanning, scanner related changes with time (day-to-day variation +/- 4%), patient repositioning (less than 1.5%), and fat concentration (residual uncertainty of approximately 1/6 of the biologic variation) are important factors influencing the accuracy and reproducibility of the values of the measured bone mineral content.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Diseases, Metabolic↗

PubMed1992

Reduced vertebral bone density in hypercalciuric nephrolithiasis.

Dual-energy x-ray absorptiometry and single-photon absorptiometry were used to determine bone density at the lumbar spine and radial shaft in 62 patients with absorptive hypercalciuria, 27 patients with fasting hypercalciuria, and 31 nonhypercalciuric stone formers. Lumbar bone density was significantly lower in patients with absorptive (-10%) as well as in those with fasting hypercalciuria (-12%), with 74 and 92% of patients displaying values below the normal mean, whereas only 48% of the nonhypercalciuric stone formers had bone density values below the normal mean. In contrast, radial bone density was similar in all three groups of renal stone formers investigated. The comparison of urinary chemistry in patients with absorptive hypercalciuria and low normal bone density compared to those with high normal bone density showed a significantly increased 24 h urinary calcium excretion on random diet and a trend toward a higher 24 h urinary uric acid excretion and a higher body mass index in patients with low normal bone density. Moreover, among the patients with absorptive hypercalciuria we found a statistically significant correlation between the spinal bone density and the 24 h sodium and sulfate excretion and the urinary pH. These results gave evidence for an additional role of environmental factors (sodium and animal proteins) in the pathogenesis of bone loss in absorptive hypercalciuria. In conclusion, our data suggest an osteopenia of trabecular-rich bone tissues in patients with fasting and absorptive hypercalciurias.

Absorptiometry, Photon↗

PubMed1993

The aged male rat as a model for human osteoporosis: evaluation by nondestructive measurements and biomechanical testing.

Effects of androgen deficiency and androgen replacement on bone density, as measured with dual-energy X-ray absorptiometry (DXA) and single photon absorptiometry (SPA), cortical ratio (cortical thickness/outside bone diameter x 100), and biomechanical properties were evaluated in 14-month-old (1 month after orchiectomy (orch) or sham-operation) and in 17-month-old (4 months after orch or sham) male rats. Whole femoral bone mineral content (BMC) and density (BMD) measured with DXA were not significantly decreased 1 month after orch. Whole femoral BMC and BMD were 10% and 8% lower in 4 months after orch (P < 0.01 and P < 0.001, respectively). This decrease was prevented by testosterone replacement. There was an excellent correlation (R = 0.99) between whole femoral BMC and femoral ash weight. Selective scanning of cortical and cancellous sites of the femur showed that both cancellous and cortical BMC and BMD were significantly decreased 4 months after orch. SPA of the right tibia confirmed a 7% decrease in cancellous BMC and BMD 4 months after orch (preventable by testosterone) but not in cortical BMD and BMC. Femoral cortical ratio decreased with age (47 +/- 2 in 14-month-old and 40 +/- 2 in 17-month-old sham rats versus 63 +/- 1 in 6-month-old male rats) due to a continuously enlarging femoral shaft. Androgen deficiency resulted in an even greater decrease of the cortical ratio 4 months after orch (36 +/- 2 in 17-month-old orch rats) that was again prevented by testosterone (47 +/- 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

PubMed1989

Osteocalcin and bone mineral content in rheumatoid arthritis.

Abnormal bone metabolism was reported in rheumatoid arthritis (RA). In order to evaluate the interest of serum osteocalcin, also called bone GLA-protein (BGP), to assess bone metabolism in RA, we studied 20 postmenopausal RA out-patients and 20 matched controls. Nine patients were treated with low-dose corticosteroids (C+) for at least one year (less than 10 mg/day, prednisolone equivalent), the remaining 11 (C-) received non-steroidal anti-inflammatory drugs (NSAID). The distal and proximal forearm bone mineral content (BMC) was measured by single photon absorptiometry, the vertebral BMC was measured by dual photon absorptiometry. A trend to low BGP was observed in the C+ group. The lowest values were observed in patients with vertebral fractures. Compared with controls, both RA groups had similar low significant BMC at the forearm sites. At the vertebral sites, the bone mineral content decrease observed in the two groups, was more marked in the C+ group. From our results, BGP did not appear as a useful index of osteoporosis in RA, except in some patients with vertebral fractures, treated with low-dose corticosteroids.

Aged↗