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Garnero, P., Hausherr, E., Chapuy, M. C., Marcelli, C., Grandjean, H., Muller, C., Cormier, C., Breart, G., Meunier, P. J., and Delmas, P. D. Increased bone turnover has been suggested as a potential risk factor for osteoporotic fractures. We investigated this hypothesis in a prospective cohort study performed on 7598 healthy women more than 75 years of age. One hundred and twenty-six women (mean years 82.5) who sustained a hip fracture ... ( view more )during a mean 22-month follow-up were age-matched with three controls who did not fracture. Baseline samples were collected prior to fracture for the measurement of two markers of bone formation and three urinary markers of bone resorption: type I collagen cross-linked N- (NTX) or C-telopeptide (CTX) and free deoxypyridinoline (free D-Pyr). Elderly women had increased bone formation and resorption compared with healthy premenopausal women. Urinary excretion of CTX and free D-Pyr, but not other markers, was higher in patients with hip fracture than in age-matched controls (p = 0.02 and 0.005, respectively). CTX and free D-Pyr excretion above the upper limit of the premenopausal range was associated with an increased hip fracture risk with an odds ratio (95% confidence interval) of 2.2 (1.3-3.6) and 1.9 (1.1-3.2), respectively, while markers of formation were not. Increased bone resorption predicted hip fracture independently of bone mass, i.e., after adjustment for femoral neck bone mineral density (BMD) and independently of mobility status assessed by the gait speed. Women with both a femoral BMD value of 2.5 SD or more below the mean of young adults and either high CTX or high free D-Pyr levels were at greater risk of hip fracture, with an odds ratio of 4.8 and 4.1, respectively, than those with only low BMD or high bone resorption. Elderly women are characterized by increased bone turnover, and some markers of bone resorption predict the subsequent risk of hip fracture independently of hip BMD. Combining the measurement of BMD and bone resorption may be useful to improve the assessment of the risk of hip fracture in elderly women ( view less ) Tsai, K. S., Hsu, S. H., Cheng, W. C., Chen, C. K., Chieng, P. U., and Pan, W. H. Whether vitamin D receptor gene (VDRG) polymorphism can be used as a predictor for bone turnover rate or bone mass remains controversial. Its role within various ethnic populations are also unsettled. We examined VDRG polymorphism using restrictive enzymes Bsm-I, Apa-I, and Taq-I in 155 men aged 22... ( view more )-88 and 113 premenopausal women aged 40-53. The bone mineral density (BMD) of the vertebrae (L2-4), proximal femur, and total body bone mineral content (tb-BMC) (women only), as well as urinary N-terminal crosslinked fragment of type I collagen (NTX), serum osteocalcin, bone isozyme of alkaline phosphatase, and caboxyterminal propeptide of type I procollagen levels were measured. Chinese men and women exhibited a low prevalence for B (absence of Bsm-I restriction site) phenotypes than white and Japanese. Within the tested samples there were 0.4% BB homozygotes, 6.7% Bb heterozygotes, and 93% bb homozygotes. The distributions of Apa-I polymorphism (9.0% AA, 42.5% Aa, and 48.5% aa) also differed from those reported for the white populations. Most of the Chinese men and women were TT homozygous (96.6%). A comparison of actual values and values adjusted for age and weight of tb-BMC and BMD at the lumbar spine, Trochanter, Ward's triangle, and femoral neck showed no significant difference among three subgroups in each of the three sets of polymorphism. Furthermore, the actual values and adjusted values (adjusted for age) of the four bone markers, respectively, showed no significant differences. We conclude that given the very low prevalence of the suspected high risk genotypes (B, A, and t), and the lack of difference among the polymorphic subgroups, VDRG polymorphism may not be an important determinant of the bone turnover rate and bone mass of Chinese men and women ( view less ) Burger, H., de, LaetCE, Weel, A. E., Hofman, A., and Pols, H. A. Hip fractures constitute a major health problem. For effective prevention, high-risk groups need to be identified. The objective here was to develop hip fracture risk scores while assessing the added value of bone mineral density relative to more conventional risk indicators. We prospectively follo... ( view more )wed during 4 years a cohort of 5208 persons (2193 men) aged 55 years and over from the Rotterdam Study, a population-based cohort study conducted in the Netherlands. Risk scores for hip fracture were constructed using several conventional risk indicators requiring interview and anthropometry only, and bone mineral density. During follow-up, 50 persons (14 men) suffered hip fracture. Hip fracture risk was independently determined by age, gender, height, the use of a walking aid, cigarette smoking, and either bone mineral density or weight. We developed two risk scores, with and without bone mineral density. The observed 4-year risk ranged from 3/3389 (0.1%) to 17/169 (10.1%) for the lowest and highest category of the score including bone mineral density, respectively. For the score without bone mineral density, these risks were 8/3117 (0.3%) and 16/144 (11.1%), respectively. The area under the receiver operating characteristic curve indicating discriminatory power was 0.88 for the risk score including, and 0.83 for the score excluding, bone mineral density (p for difference = 0.04). In conclusion, risk scores with and without bone mineral density measurement can be used for hip fracture risk assessment in elderly persons. While the score with bone mineral density has a modestly better performance, the score requiring interview and anthropometry only may be especially useful in primary care settings ( view less ) Hanley, D. A., Brown, J. P., Tenenhouse, A., Olszynski, W. P., Ioannidis, G., Berger, C., Prior, J. C., Pickard, L., Murray, T. M., Anastassiades, T., Kirkland, S., Joyce, C., Joseph, L., Papaioannou, A., Jackson, S. A., Poliquin, S., Adachi, J. D., and Canadian, MulticentreOsteoporosisStudyResearchGroup This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 1... ( view more )2 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies ( view less ) Lespessailles, E., Poupon, S., Adriambelosoa, N., Pothuaud, L., Siroux, V., Bouillon, S., and Benhamou, C. L. BACKGROUND: Glucocorticoids may increase bone fragility via mechanisms independent from their bone mass reducing effect. OBJECTIVE: To study relationships between osteoporotic fractures and bone mineral density in patients on long-term glucocorticoid therapy. PATIENTS AND METHODS: We studied 121 wo... ( view more )men with a mean age of 60.4 +/- 14.3 years on long-term glucocorticoid therapy (cumulative dose > or = 1 g of prednisone equivalent, duration > or = 6 months) for rheumatoid arthritis (n = 38), polymyalgia rheumatica or giant cell arteritis (n = 26), connective tissue disease (n = 15), asthma (n = 14), another inflammatory joint disease (n = 14), or another condition (n = 14). The control group was composed of 125 subjects who had the same mean age and met the same exclusion criteria as the case group. Bone mineral density was measured at the lumbar spine and femoral neck using a Hologic QDR 4500 unit. In subjects with back pain, radiographs of the thoracic and lumbar spine were obtained to look for fractures. RESULTS: The odds ratio for a bone mineral density decrease of one standard deviation at the femoral neck was 1.68 (1.20-2.35) in patients with a cumulative glucocorticoid dose of 10 g of prednisone equivalent and 1.67 (1.22-2.29) in those with a glucocorticoid therapy duration of 2 years. Sixty-eight fractures were recorded in 56 patients (46% of the overall patient group). Even after adjustment on age, glucocorticoid therapy duration, and dose, mean bone mineral density values at the lumbar spine and femoral neck were significantly lower in the subgroup of patients with fractures than in the subgroup without fractures. Sensitivity and specificity of bone mineral density at the femoral neck and/or lumbar spine for the diagnosis of vertebral fracture and/or peripheral fracture were 73% and 51%, respectively. In the stepwise logistic regression model, factors explaining the presence of fractures were as follows, in hierarchical order: age; absence of calcium/vitamin D supplementation, femoral neck T-score, and glucocorticoid dose. CONCLUSION: Our data are compelling evidence that bone mineral density is a major determinant of the fracture risk in patients with glucocorticoid-induced osteoporosis ( view less ) Ebbesen, E. N., Thomsen, J. S., Beck-Nielsen, H., Nepper-Rasmussen, H. J., and Mosekilde, Li Vertebral bone density is evaluated mainly by dual-energy X-ray absorptiometry (DXA) or quantitative computed tomography (QCT). Densitometry is used as an estimator of bone strength and forms the basis for choice of treatment. DXA expresses bone density in grams per square centimeter (area density)... ( view more ) and QCT expresses bone density in milligrams per cubic centimeter (volumetric density). The aim of this study was to identify the differences between the two techniques, DXA and QCT, when applied to a group of female and male subjects over a wide age range. The data consisted of 221 lumbar vertebral bodies (L3 and L4) excised at autopsy. There were 90 females with a mean age of 65.6 (range 18-94) years and 131 males with a mean age of 62.0 (range 21-94) years. The vertebrae were scanned en bloc in demineralized water in Plexiglas containers with both DXA and QCT. DXA was performed using posteroanterior (PA) and lateral projection. QCT was performed in the center of each vertebra with 1 cm slice thickness. Both methods showed decreasing bone density with age. Lateral DXA showed a decrease in bone density with age from approximately 0.8 g/cm2 to approximately 0.4 g/cm2. QCT showed a decrease in bone density with age from approximately 180 mg/cm3 to approximately 30 mg/cm3. Lateral DXA bone mineral densities (BMD) were correlated with QCT densities in both females (r2 = 0.68, p < 0.00001) and males (r2 = 0.53, p < 0.00001), but females had constantly lower DXA BMDs than males at a given QCT density. QCT and width-adjusted midlateral DXA (g/cm3) were significantly correlated, with r2 = 0.64 (p < 0.00001) for females and r2 = 0.61 (p < 0.00001) for males. In conclusion, age- and gender-related differences in human vertebral bone density were shown to be dependent on the scanning method used. DXA bone mineral content (BMC) and BMD showed that females had lower values than males at all ages. When the 'volumetric' DXA measurements and QCT were used, the females had the highest densities in the younger decades and males had the highest densities in the oldest decades. Finally, the area density (BMD) measured by DXA was lower in females than in males with identical QCT volumetric bone densities ( view less ) Gerdhem, P., Ivaska, K. K., Alatalo, S. L., Halleen, J. M., Hellman, J., Isaksson, A., Pettersson, K., Vaananen, H. K., Akesson, K., and Obrant, K. J. We studied the ability of various markers of bone turnover to predict fracture in 1040 randomly recruited 75-year-old women. A total of 178 of the women sustained at least one fracture during follow-up (mean, 4.6 years). In elderly women, TRACP5b and urinary fragments of osteocalcin are promising n... ( view more )ew markers for prediction of fracture, in particular, vertebral fracture. Introduction: Biochemical markers reflecting bone turnover may improve the prediction of fractures. Materials and Methods: The ability of 10 markers of bone turnover to predict fracture in 1040 elderly women in the Malmo[spacing diaeresis] OPRA study was studied. Serum bone-specific alkaline phosphatase and four different forms of serum osteocalcin (S-OC) were analyzed as markers of bone formation and serum C-terminal cross-linking telopeptides of type I collagen (S-CTX), serum TRACP isoform 5b (S-TRACP5b) and urinary free deoxypyridinoline (U-DPD) as markers of bone resorption. Two novel assays for osteocalcin fragments in urine (U-OC) were analyzed. Areal BMD (aBMD) was measured by DXA in the femoral neck and lumbar spine. Results: In total, 231 fractures were sustained by 178 of the women during a 3- to 6.5-year (mean, 4.6 years) follow-up period. When women with prospective fractures were compared with women without fractures, S-TRACP5b, S-CTX, one S-OC, and one U-OC were higher in women with a fracture of any type (all p < 0.05), and all bone markers were higher in women with clinical vertebral fracture (all p < 0.05). Markers were not significantly elevated in women with hip fracture. When women within the highest quartile of a bone marker were compared with all others, S-TRACP5b and one U-OC predicted the occurrence of a fracture of any type (odds ratio [OR]), 1.55 and 1.53; p < 0.05). S-TRACP5b, the two U-OCs, and S-CTX predicted vertebral fracture (OR, 2.28, 2.75, 2.71, and 1.94, respectively; all p < 0.05), and the predictive value remained significant for S-TRACP5b and the two U-OCs after adjusting for aBMD (OR, 2.02-2.25; p < 0.05). Bone markers were not able to predict hip fracture. Conclusion: These results show that biochemical markers of bone turnover can predict fracture, and in particular, fractures that engage trabecular bone. S-TRACP5b and U-OC are promising new markers for prediction of fracture ( view less ) Morote, J., Trilla, E., Esquena, S., Abascal, J. M., Segura, R. M., Catalan, R., Encabo, G., and Reventos, J. The objective of this study was to evaluate the usefulness of serum determination of bone alkaline phosphatase (BAP) in the diagnosis of osteoporosis in men with prostate cancer under androgen ablation. Serum levels of BAP and bone mineral density (BMD) were assessed in 110 patients with non-metast... ( view more )atic, treated prostate cancer. Fifty-eight patients were under androgen deprivation during a period between two and 96 months and 52 had been submitted only to radical prostatectomy. Mean serum BAP was 11.8 ng/mL in patients with normal BMD, 16.7 ng/mL in patients with osteopenia (p. 0.058), and 19.3 ng/mL in patients with osteoporosis (p = 0.044). The correlation between serum BAP and BMD was significant (p. 0.006) but with an index of only 0.26. Receiver operating characteristic analysis for the diagnosis of osteoporosis showed an area under the curve of 0.608. None of the cutoff points that provided specificities of 75%, 90% and 95% gave significant distributions. The positive and negative predictive values as well as the odds ratios were not of any clinical usefulness. We conclude that serum BAP should not be considered a good marker for the diagnosis of osteoporosis in men with prostate cancer. Therefore, BAP serum determination cannot replace bone densitometry as a diagnostic tool ( view less ) Follet, H., Boivin, G., Rumelhart, C., and Meunier, P. J. Strength of bones depends on bone matrix volume (BMV), bone microarchitecture, and also on the degree of mineralization of bone (DMB). We have recently shown in osteoporotic patients treated with alendronate that fracture risk decreased and bone mineral density increased with a parallel increase of... ( view more ) the DMB due to prolonged secondary mineralization but without modifications of BMV or bone microarchitecture. DMB and strength were both measured at the tissue level in calcaneus bone samples taken at autopsy from 20 subjects (aged 78 +/- 8 years, 8 women, 12 men) who died suddenly without apparent bone disease. DMB parameters measured on microradiographs (mean DMB, distribution of DMB, most frequent maximum DMB value, and width at half maximum, an index reflecting the homogeneity of DMB) were compared with those reported in iliac cancellous bone samples of 43 human bones. Histomorphometric measurements of microarchitectural parameters (TbTh, TbN, and TbSp) were also measured. Compression tests were performed on contiguous samples of the same calcaneus on a universal screw-driven machine (Schenck RSA 250). A 5000-N load cell (TME, F 501 TC) measured the compressive load. The displacement was measured directly on the sample using a specific displacement transducer developed by the [left pointing guillemet]Laboratoire de Me[spacing acute]canique des Contacts et des Solides (LaMCoS).[right pointing guillemet] The apparent Young's modulus (E), the maximal strength ([sigma]max), and the work (W) until failure were measured. In human cancellous bone tissue, mean DMB (+/- SD) was higher in calcaneus (1.135 +/- 0.147 g/cm3) than in iliac crest (1.098 +/- 0.077 g/cm3). The mean most frequent maximum DMB values (mean DMB freq. max.) were 1.118 +/- 0.175 g/cm3 in calcaneus and 1.108 +/- 0.095 g/cm3 in iliac samples, and DMB was more heterogeneous in calcaneus than in iliac samples (mean width at half maximum were 0.270 +/- 0.127 versus 0.227 +/- 0.056 g/cm3, respectively). Compression tests revealed significant positive linear correlations between DMB and both elastic modulus (r2 = 0.69) and maximal strength (r2 = 0.69). Correlations with DMB persisted (P < 0.003) even after adjustment for both calcified bone volume, for the Young's modulus (E), the maximal strength ([sigma]max) (r2 = 0.44 and 0.41, respectively), and microarchitectural parameters (0.50 < r2 < 0.56, P < 0.001). The same results were obtained with the work to fracture (W) (0.23 < r 2 < 0.46, P < 0.045). We conclude that the more the cancellous tissue was mineralized, the higher was its stiffness and compressive strength. This may explain the increase in bone strength when DMB is modified in a physiological range without necessary changes of BMV and bone microarchitecture. The impact of such modifications on fracture risk and the therapeutic implications of these data remain to be analyzed. (C) 2003 Elsevier Inc. All rights reserved ( view less ) Kerr, D., Ackland, T., Maslen, B., Morton, A., and Prince, R. Understanding the stress/strain relationship between exercise and bone is critical to understanding the potential benefit of exercise in preventing postmenopausal bone loss. This study examined the effect of a 2-year exercise intervention and calcium supplementation (600 mg) on bone mineral density... ( view more ) (BMD) in 126 postmenopausal women (mean age, 60 +/- 5 years). Assignment was by block randomization to one of three groups: Strength (S), fitness (F), or nonexercise control (C). The two exercise groups completed three sets of the same nine exercises, three times a week. The S group increased the loading, while the F group had additional stationary bicycle riding with minimal increase in loading. Retention at 2 years was 71% (59% in the S group, 69% in the F group, and 83% in the C group), while the exercise compliance did not differ between the exercise groups (S group, 74 +/- 13%; F group, 77 +/- 14%). BMD was measured at the hip, lumbar spine, and forearm sites every 6 months using a Hologic 4500. Whole body BMD also was measured every 6 months on a Hologic 2000. There was no difference between the groups at the forearm, lumbar spine, or whole body sites. There was a significant effect of the strength program at the total (0.9 +/- 2.6%; p < 0.05) and intertrochanter hip site (1.1 +/- 3.0%; p < 0.01). There was a significant time and group interaction (p < 0.05) at the intertrochanter site by repeated measures. This study shows the effectiveness of a progressive strength program in increasing bone density at the clinically important hip site. We concluded that a strength program could be recommended as an adjunct lifestyle approach to osteoporosis treatment or used in combination with other therapies. (J Bone Miner Res 2001;16:175-181) ( view less ) Jarvinen, T. L. N., Kannus, P., Pajamaki, I., Vuohelainen, T., Tuukkanen, J., Jarvinen, M., and Sievanen, H. To first test the possible effect of gender on the responsiveness of growing rat skeleton to mechanical loading, 5-week-old littermates of 25 male and 25 female rats were subjected to either free-cage activity or treadmill training for a period of 14 weeks (experiment 1). Using peripheral quantitat... ( view more )ive computed tomography (pQCT) and mechanical testing of the femoral neck, we observed female rats exhibiting a clearly lower responsiveness to external loading than male rats (+3.0% vs +25% in cross-sectional area (CSA), +4.2% vs +27% in the bone mineral content (BMC), -0.6% vs +10% in volumetric bone mineral density (BMD), and +4.7% vs +28% in fracture strength (Fmax) of the femoral neck). Also, relative to the mechanical demands placed on the skeleton, the bones of the young female rats were considerably denser (>50%) than those of the males. In the subsequent experiment 2, we repeated the above-noted first experiment with 33-week-old rats and observed virtually identical exercise-induced benefits (+2.1% vs +10% in CSA, +3.4% vs +18% in BMC, +2.5% vs +23% in BMD, and -1.1% vs +27% in Fmax in females vs males, respectively) and the growth/puberty-related condensation of mineral into female bones. Finally, in experiment 3, 60 littermates of 3-week-old female rats were first subjected to sham operation or ovariectomy and then further randomized to exercise or control groups, respectively, to study whether the condensation of mineral into female bones and their lower responsiveness to loading were attributable to the effects of estrogen. At the end of the 16-week intervention, our pQCT and mechanical testing analysis showed not only the anticipated effect of reduced bone density in the ovariectomized rats (~ -20%) but also the hypothesized better responsiveness to mechanical loading in these estrogen-depleted rats (-3.5% vs +9.1% in CSA, -0.4% vs +12% in BMC, +4. 4% vs +9.6% in BMD, and -4.2% vs +16% in Fmax in SHAM vs OVX, respectively). In conclusion, the results of our series of three experiments suggest that as such estrogen seems to have very little primary effect on the sensitivity of female bone to respond to external loading, but rather deposits extra stock of mineral into female bones in puberty. This estrogen-driven extra condensation of the female skeleton seems to persist into adulthood, simultaneously damping the responsiveness of the female skeleton to mechanical loading. copyright 2003 Elsevier Science (USA). All rights reserved ( view less ) Jarvinen, T. L., Kannus, P., Pajamaki, I., Vuohelainen, T., Tuukkanen, J., Jarvinen, M., and Sievanen, H. To first test the possible effect of gender on the responsiveness of growing rat skeleton to mechanical loading, 5-week-old littermates of 25 male and 25 female rats were subjected to either free-cage activity or treadmill training for a period of 14 weeks (experiment 1). Using peripheral quantitat... ( view more )ive computed tomography (pQCT) and mechanical testing of the femoral neck, we observed female rats exhibiting a clearly lower responsiveness to external loading than male rats (+3.0% vs +25% in cross-sectional area (CSA), +4.2% vs +27% in the bone mineral content (BMC), -0.6% vs +10% in volumetric bone mineral density (BMD), and +4.7% vs +28% in fracture strength (F(max)) of the femoral neck). Also, relative to the mechanical demands placed on the skeleton, the bones of the young female rats were considerably denser (>50%) than those of the males. In the subsequent experiment 2, we repeated the above-noted first experiment with 33-week-old rats and observed virtually identical exercise-induced benefits (+2.1% vs +10% in CSA, +3.4% vs +18% in BMC, +2.5% vs +23% in BMD, and -1.1% vs +27% in F(max) in females vs males, respectively) and the growth/puberty-related condensation of mineral into female bones. Finally, in experiment 3, 60 littermates of 3-week-old female rats were first subjected to sham operation or ovariectomy and then further randomized to exercise or control groups, respectively, to study whether the condensation of mineral into female bones and their lower responsiveness to loading were attributable to the effects of estrogen. At the end of the 16-week intervention, our pQCT and mechanical testing analysis showed not only the anticipated effect of reduced bone density in the ovariectomized rats ( approximately -20%) but also the hypothesized better responsiveness to mechanical loading in these estrogen-depleted rats (-3.5% vs +9.1% in CSA, -0.4% vs +12% in BMC, +4.4% vs +9.6% in BMD, and -4.2% vs +16% in F(max) in SHAM vs OVX, respectively). In conclusion, the results of our series of three experiments suggest that as such estrogen seems to have very little primary effect on the sensitivity of female bone to respond to external loading, but rather deposits extra stock of mineral into female bones in puberty. This estrogen-driven extra condensation of the female skeleton seems to persist into adulthood, simultaneously damping the responsiveness of the female skeleton to mechanical loading ( view less ) Schoenau, E., Neu, C. M., Rauch, F., and Manz, F. It is well established that puberty affects the geometry of cortical bone differently in females and males. In the present study we investigated whether there are also gender differences in the volumetric bone mineral density of the cortical compartment (BMDcort). BMDcort was determined at the prox... ( view more )imal radial diaphysis in 362 healthy children and adolescents (age 6-23 years; 185 females, 177 males) and in 107 adults (age 29-40 years; 88 women, 19 men) using peripheral quantitative computed tomography (pQCT). The densitometric result for BMDcort was similar in prepubertal girls and boys, but was significantly higher in females after pubertal stage 3. pQCT results for BMDcort are influenced by cortical thickness due to the partial volume effect. Therefore, these gender differences were reanalyzed in groups of subjects of the same developmental stage who were matched for cortical thickness. Thus calculated, no gender difference in BMDcort was detected in prepubertal children. However, adolescent females after pubertal stage 3 and adult women had a 3%-4% higher BMDcort than males at the same developmental stage. BMDcort is an integrated measure of both cortical porosity and mean material density of cortical bone. The metabolic activity of cortical bone (intracortical remodeling) increases cortical porosity and decreases the mean material density of cortical bone. Our results therefore suggest that intracortical remodeling is lower in postpubertal females than in males. copyright 2002 by Elsevier Science Inc. All rights reserved ( view less ) Yamada, M., Ito, M., Hayashi, K., Sato, H., and Nakamura, T. We conducted volunteer studies to assess age-related changes of mandibular condyle bone mineral density (BMD) and its correlation to the spinal BMD. Quantitative computed tomography was performed on the condyles and spines (L1-3) of 210 healthy subjects (114 men and 96 women, aged 5-85 years). A se... ( view more )parate study was performed on 73 young student subjects (39 men and 34 women, aged 23-25 years). The mandibular condyle BMD showed a decrement rate similar to spinal BMD in men, but in women the decrement rate of the mandibular condyle BMD was lower than that of the L1-3 BMD. On the other hand, correlation coefficients in BMD between the mandibular condyle and spine were similar in women and men. Gender-related differences were found to be dramatic when assessed in the young student group; the mandibular condyle and spinal BMDs were highly correlated in women (r = 0.82, p < 0.0001), but no correlation was found in men (r = 0.22). Taken together, these results suggest that the same regulatory mechanisms exist in the mandibular condyle and spine BMDs. However, aside from the spine BMD, additional undefined factor(s), including mechanical stress from the occlusion, may be involved in maintaining mandibular BMD ( view less ) Liao, E. Y., Wu, X. P., Liao, H. J., Zhang, H., and Peng, J. To understand the effects of skeletal size of the lumbar spine on areal bone mineral density (aBMD), volumetric bone mineral density (vBMD), and the diagnosis of osteoporosis in postmenopausal women, we measured the projected bone area, bone mineral content (BMC), aBMD, and vBMD at the anteroposter... ( view more )ior and lateral lumbar spines in a population of 1081 postmenopausal Chinese women, 42 to 86 years of age. The results indicated that, at the anteroposterior and lateral lumbar spine, there were significant positive correlations between bone area and both BMC ( r = 0.606; P = 0.000 and r = 0.610; P = 0.000) and aBMD ( r = 0.270; P = 0.000 and r = 0.182; P = 0.000), but not vBMD ( r = -0.055; P = 0.000 and r = 0.000; P = 0.929). When bone area at the anteroposterior spine changed by +/-1 SD, the BMC, aBMD, and vBMD correspondingly changed by 28.2%, 10.1%, and 1.69% on the basis of their respective means. When a variation of +/-1 SD was observed in bone area at the lateral spine, BMC and aBMD, correspondingly changed by 25.9% and 6.18% on the basis of their respective means, while vBMD indicated no change. Through comparisons among large-, intermediate-, and small-bone area groups, significant differences were found in the means of subjects' heights, weights, BMC, and vBMD at the anteroposterior and lateral lumbar spines, as well as in the detection rates of osteoporosis by aBMD ( P = 0.000). Detection rates of osteoporosis by aBMD at the anteroposterior spine and by aBMD at the lateral spine, and by vBMD were 44.1%, 55.5%, and 49.7%, respectively, in the total population; 31.4%, 41.7%, and 53.7%, respectively, in the large-bone area group; 43.3%, 55.9%, and 50.5%, respectively, in the intermediate-bone area group; and 61.7%, 70.0%, and 42.5%, respectively, in the small-bone area group. No significant differences were found in the detection rates of osteoporosis by vBMD among the groups. The results of multiple linear regression revealed that the major factors influencing skeletal size and aBMD of the lumbar spine were height and weight. Therefore, in menopausal women of the same ethnic group and age, the skeletal size of the lumbar spine would have significant influence upon aBMD and the diagnosis of osteoporosis, i.e., the larger the spinal size, the greater the aBMD and the lower the osteoporosis detection rate, while, conversely, the smaller the skeletal size, the smaller the aBMD and the higher the osteoporosis detection rate. When we use aBMD of the lumbar spine to diagnose osteoporosis in a population with different body sizes, we need to take this body size difference into account. When we use vBMD to diagnose osteoporosis, the effect of body size on BMD will diminish ( view less ) Kaste, S. C., Shidler, T. J., Tong, X., Srivastava, D. K., Rochester, R., Hudson, M. M., Shearer, P. D., and Hale, G. A. Our purpose was to evaluate frequency and severity of bone mineral decrements and frequency of osteonecrosis in survivors of pediatric allogeneic bone marrow transplantation (alloBMT). We retrospectively reviewed demographic information, treatment, magnetic resonance (MR) imaging studies (hips and ... ( view more )knees), and bone mineral density (BMD) studies of 48 patients as measured by quantitative computed tomography (QCT). In all, 24 patients were male; 37 were Caucasian. Median age at alloBMT was 10.3 years (1.6-20.4 years). Of the 48 patients, 43 underwent QCT. Median time between alloBMT and imaging was 5.1 years (1.0-10.2 years). Median BMD Z-score was -0.89 (-4.06 to 3.05). BMD Z-score tended to be associated with female sex (P=0.0559) but not with age at BMT, race, primary diagnosis, time from alloBMT, T-cell depletion of graft, total-body irradiation, or acute/chronic graft-versus-host disease (GVHD). MR showed osteonecrosis in 19 of 43 (44%). We found no associations between osteonecrosis and sex, race, diagnosis, age at BMT, history of GVHD, time from BMT, or T-cell depletion. Seven patients (15%) had MR changes of osteonecrosis and BMD Z-scores of less than -1s.d. We conclude that pediatric alloBMT survivors have decreased BMD and are at risk of osteonecrosis. They should be monitored to assure early intervention that may ameliorate adverse outcomes. copyright 2004 Nature Publishing Group All rights reserved ( view less ) Muehleman, C., Lidtke, R., Berzins, A., Becker, J. H., Shott, S., and Sumner, D. R. We investigated, at the whole bone level, the contribution of bone density and geometry to the fracture load of the second metatarsal, a bone that is prone to stress fracture. Dual-energy X-ray absorptiometry (DXA) was used to determine the areal bone mineral density (BMD), projected area of bone, ... ( view more )and bone mineral content. Peripheral quantitative computed tomography (pQCT) was used to determine the volumetric cortical bone mineral density (vCtBMD) and cross-sectional moment of interia. Various metatarsal linear dimensions were also measured. The load at failure in cantilever bending was determined. The only linear dimension that had a significant correlation with load at failure was the height of the metatarsal base (r(2) = 0.30, p = 0.008). Utilizing all of the information provided by DXA gave no greater indication of whole bone strength than just BMD alone (adjusted r(2) = 0.40, p = 0.001). Using all of the information provided by pQCT gave no greater indication of whole bone strength than just vCtBMD alone (r(2) = 0. 46, p < 0.001). Volumetric cortical density and BMD were strongly correlated (r(2) = 0.81, p < 0.001). Our data suggest that, in the human second metatarsal, a variable such as material strength (as inferred from cortical density), and not geometry, may be the major factor in determining cantilever load to failure ( view less ) Hochberg, M. C., Lethbridge-Cejku, M., Scott, W. W. J., Reichle, R., Plato, C. C., and Tobin, J. D. To examine the association of upper extremity bone mass with osteoarthritis (OA) of the knee, bilateral standing knee radiographs, taken between 1985 and 1991, in 430 Caucasian male and 266 Caucasian female subjects aged 40 years and above in the Baltimore Longitudinal Study of Aging, were read by ... ( view more )one investigator for grade of OA using Kellgren-Lawrence scales. Several measures of upper extremity bone mass, size, and density, including combined cortical thickness (CCT), total width and percentage of cortical area of the second metacarpal, and bone mineral content (BMC), width, and density of the distal third of the left radius measured with single photon absorptiometry, were assessed at the same visit. In univariate analyses, men and women with definite knee OA were significantly older, men had significantly greater radial width, and women had significantly lower bone mass as measured by both CCT and BMC. After adjustment for age and body weight, however, men with knee OA had significantly higher BMC and radial width while neither of these measures of upper extremity bone mass and size was significantly associated with the presence of definite knee OA in women. Neither measure of upper extremity bone density was significantly associated with definite knee OA in either sex. These data suggest that, although men (but not women) with definite knee OA have significantly higher levels of adjusted radial bone mass and size, subjects with knee OA do not have significantly higher levels of adjusted bone mineral density at either upper extremity site ( view less ) Ebbesen, E. N., Thomsen, J. S., Beck-Nielsen, H., Nepper-Rasmussen, H. J., and Mosekilde, L. Vertebral bone density is evaluated mainly by dual-energy X-ray absorptiometry (DXA) or quantitative computed tomography (QCT). Densitometry is used as an estimator of bone strength and forms the basis for choice of treatment. DXA expresses bone density in grams per square centimeter (area density)... ( view more ) and QCT expresses bone density in milligrams per cubic centimeter (volumetric density). The aim of this study was to identify the differences between the two techniques, DXA and QCT, when applied to a group of female and male subjects over a wide age range. The data consisted of 221 lumbar vertebral bodies (L3 and L4) excised at autopsy. There were 90 females with a mean age of 65.6 (range 18-94) years and 131 males with a mean age of 62.0 (range 21-94) years. The vertebrae were scanned en bloc in demineralized water in Plexiglas containers with both DXA and QCT. DXA was performed using posteroanterior (PA) and lateral projection. QCT was performed in the center of each vertebra with 1 cm slice thickness. Both methods showed decreasing bone density with age. Lateral DXA showed a decrease in bone density with age from approximately 0.8 g/cm2 to approximately 0.4 g/cm2. QCT showed a decrease in bone density with age from approximately 180 mg/cm3 to approximately 30 mg/cm3. Lateral DXA bone mineral densities (BMD) were correlated with QCT densities in both females (r2 = 0.68, p < 0.00001) and males (r2 = 0.53, p < 0.00001), but females had constantly lower DXA BMDs than males at a given QCT density. QCT and width-adjusted midlateral DXA (g/cm3) were significantly correlated, with r2 = 0.64 (p < 0.00001) for females and r2 = 0.61 (p < 0.00001) for males. In conclusion, age- and gender-related differences in human vertebral bone density were shown to be dependent on the scanning method used. DXA bone mineral content (BMC) and BMD showed that females had lower values than males at all ages. When the "volumetric" DXA measurements and QCT were used, the females had the highest densities in the younger decades and males had the highest densities in the oldest decades. Finally, the area density (BMD) measured by DXA was lower in females than in males with identical QCT volumetric bone densities ( view less ) Nagasaki, K., Kikuchi, T., Hiura, M., and Uchiyama, M. The purpose of this study was to determine the relationship between BMD and childhood obesity. We examined 1070 obese children (722 boys and 348 girls) aged 7 to 15 years. Their mean relative weight, as a percentage of the standard weight for age, height, and sex, was 152.9 +/- 14%. BMD was assesse... ( view more )d, by a digital image processing method, in the second metacarpal bone of the left hand. We compared our results with those of healthy nonobese Japanese children based on both chronological and bone age. Mean BMD values for bone age in the obese children were significantly higher than those in control groups in boys aged 11 years and under and girls 9 years and under. On the other hand, in boys over 12 years old, BMD values for bone age were lower than those in the control groups. In girls over 11 years old, BMD values tended to be lower than those in the control groups. In conclusion, we studied the BMD of obese children from the point of view of advanced bone age. Our results showed that BMD was higher than in prepubertal obese children, but a low BMD value was found after puberty, due to poor gain of BMD during puberty. It is important to prevent obesity in childhood in order to prevent the low BMD after puberty ( view less ) Khunkitti, N., Aswaboonyalert, N., Songpatanasilp, T., and Pipithkul, S. Fractures in the elderly as the result of minor trauma or normal physiological stress in daily activities usually occur in load-bearing body areas such as the lumbar spine and the neck or trochanter of the femur, causing high morbidity and mortality. Surveillance of high-risk Thai elderly with low ... ( view more )bone mineral density by determining the cutoff point as the fracture threshold may guide us in the proper management for preventing these unpleasant events. Of 329 elderly with age range of 50-110 years, 63 with lumbar spine fracture and 55 with hip fracture were descriptively and studied prospectively during May 1997 to December 1998 at Pramongkutklao Hospital. Bone mineral density (BMD) was analyzed to determine the fracture threshold using a receiver-operating characteristic (ROC) curve and compared with the total BMD at the lumbar spine and proximal femur. The cutoff point of the lumbar BMD at 0.799 g/cm2 (78.30% sensitivity, 73.60% specificity, and 74.5% accuracy) yields the likelihood of lumbar spine or hip fracture. For the femoral BMD, the cutoff point at 0.649 g/cm2 (92.5% sensitivity, 73.2% specificity, and 73.05% accuracy) is also used to predict the likelihood of lumbar spine or hip fracture. Of the nonfracture group, 27.33% had a total BMD value below the fracture threshold. In conclusion, early prevention among the elderly to decrease the risks of fracture is very important. Also, the detection and fracture prevention for normal population who had BMD below the fracture threshold are interesting. The BMD measurements and the loss of bone mass in Thai elderly people and the other risks of fracture need further studies ( view less ) Ebbesen, E. N., Thomsen, J. S., Beck-Nielsen, H., Nepper-Rasmussen, H. J., and Mosekilde, L. This study was designed to evaluate age- and gender-related differences in vertebral bone mass, density, and strength by dual-energy X-ray absorptiometry (DXA), quantitative computed tomography (QCT), peripheral QCT (pQCT), ash measurements, and biomechanical testing. The material comprised human l... ( view more )umbar vertebral bodies (L3) from 51 females and 50 males (age-range: 18-96 years). The results showed that females had significantly lower vertebral body bone mass (ash weight) than males at any given age. The decline in bone mass with age was parallel for females and males. The different bone density measurements-cancellous ash density, total vertebral body ash density, DXA bone mineral density, QCT, and pQCT-showed no gender-related difference concerning numeric value or changes with age. Morphometrical measurements showed that females had smaller vertebral bodies (volumes) than males. Hence the females had significantly smaller cross-sectional area (CSA) of L3 than males (11.6 cm2 and 14.4 cm2, respectively). This led to females having lower maximum compressive load (N) than males at all ages, whereas maximum compressive stress (load/CSA) showed no gender-related difference. In conclusion, females have lower vertebral body bone mass than males at any given age, due to smaller vertebral bodies. Hence, maximum compressive load (strength not corrected for size) was lower in females. Vertebral body cancellous bone density and total-vertebral body density were equal when comparing genders, and no gender differences were found in the size-corrected strength: maximum compressive stress. The decrease with age in vertebral body compressive strength decrease was twice as large as the age decrease in density ( view less ) Petersen, M. M., Gehrchen, P. M., Nielsen, P. K., and Lund, B. We measured prospectively early changes (0-6 months) in bone mineral of the hip, the lumbar spine, and the tibia following tibial shaft fractures (n = 12), and in a cross-sectional study we evaluated the maximal amount of bone loss possible at the hip and tibia following long-term (average 3 years)... ( view more ) impaired limb function as a consequence of complicated tibial shaft fractures [delayed union or nonunion (n = 7), chronic osteomyelitis (n = 5), decreased limb length (n = 1), or bone defect (n = 1)]. Bone mineral measurements were performed by dual energy X-ray absorptiometry. Following tibial shaft fractures, a significant decrease in bone mineral density (BMD) was seen at the hip reaching 7% [confidence limits (CL): -10.2%; -3.5%] and 14% (CL: -19.6; -7.8%) after 6 months for the femoral neck and greater trochanter, respectively. In the proximal tibia, bone mineral content (BMC) decreased and was 19% (CL: -27.4%; -9.9%) below the initial value after 6 months. BMD of the lumbar spine remained unchanged. In the cross-sectional study, BMC in the tibia of the injured legs was 43% (CL: -53.2%; -31.9%) below the value in the healthy contralateral legs, and BMD in the femoral neck and greater trochanter, respectively, was 22% (CL: -27.4%; -17.6%) and 24% (CL: -36.3%; -12.1%) below the values in the healthy contralateral legs. With respect to the expected age-related decay of bone mineral after peak bone mass, the loss of bone mineral of the hip and tibia associated with tibial shaft fractures may be considered of clinical importance with increased risk of sustaining a fragility fracture of the lower extremity later in life; and the complicated fractures may even represent a present risk of fracture ( view less ) Suman, V. J., Atkinson, E. J., O'Fallon, W. M., Black, D. M., and Melton, L. J.A statistical model for predicting a woman's lifetime risk of hip fracture using her bone mineral density at menopause has been proposed by Black et al. (1992b). We made an additional assumption concerning the correlation of bone mineral density between any two ages among postmenopausal women and a... ( view more )pplied the modified model to baseline ages between 50 and 85 years and any bone mineral density level likely to be observed in the population. The results are displayed in a form more convenient for application of this model in the clinical setting ( view less ) Legrand, E., Chappard, D., Pascaretti, C., Duquenne, M., Krebs, S., Rohmer, V., Basle, M. F., and Audran, M. Some studies have indicated that the risk of fragility fractures in men increases as bone mineral levels decrease, but there is an overlap in the bone mineral density (BMD) measurements between patients with or without fractures. Furthermore, it has been suggested that the biomechanical competence ... ( view more )of trabecular bone is dependent not only on the absolute amount of bone present but also on the trabecular microarchitecture. In the present study, 108 men (mean age 52.1 years) with lumbar osteopenia (T score < -2.5) were recruited to examine the relationships between BMD, architectural changes in trabecular bone, and the presence of vertebral fractures. Lumbar BMD was assessed from L2 to L4 in the anteroposterior view with dual-energy X-ray absorptiometry. At the upper left femur, hip BMD was measured at the transcervical site. Spinal X-ray films were analyzed independently by two trained investigators, and vertebral fracture was defined as a reduction of at least 20% in the anterior, middle, or posterior vertebral height. Transiliac bone biopsy specimens were obtained for all patients. Histomorphometric studies were performed on an image analyzer, and the following parameters were determined: trabecular bone volume (BV/TV), trabecular thickness (Tb.Th), number (Tb.N), and separation (Tb.Sp), interconnectivity index (ICI), characterization of the trabecular network (node count and strut analysis), and star volume of the marrow spaces. Spinal radiographs evidenced at least one vertebral crush fracture in 62 patients (group II) and none in 46 patients (group I). After adjusting for age, body mass index, and BMD, there were no significant differences between the two groups in BV/TV, Tb.Th, or star volume. In contrast, the mean values of ICI, free end-to-free end struts (FF/TSL), and Tb.Sp were significantly higher, whereas Tb.N and node-to-node struts (NN/TSL) were lower in patients with at least one vertebral fracture. Logistic regression analysis showed that only ICI, FF/TSL, NN/TSL, and Tb.N were significant predictors of the presence of vertebral fracture: odds ratios for an alteration of 1 SD ranged from 1.7 (1.0-3.2) for NN/TSL to 3.2 (1.1-10.1) for ICI. Patients with at least three vertebral fractures (n = 23) were categorized as "multiple fractures." The results of logistic regression showed that spine BMD, BV/TV, and all architectural parameters were significant predictors of multiple vertebral fractures: odds ratios for an alteration of 1 SD ranged from 2.2 (1.1-4.6) for star volume to 3.7 (1.4-9.7) for ICI. These results strongly suggest that bone trabecular microarchitecture is a major and independent determinant of vertebral fractures in middle-aged men with osteopenia ( view less )
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