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Bone Measurements (bone + measurement)
Selected AbstractsComparison Insight Bone Measurements by Histomorphometry and ,CT,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2005Daniel Chappard MD Abstract Morphometric analysis of 70 bone biopsies was done in parallel by ,CT and histomorphometry. ,CT provided higher results for trabecular thickness and separation because of the 3D shape of these anatomical objects. Introduction: Bone histomorphometry is used to explore the various metabolic bone diseases. The technique is done on microscopic 2D sections, and several methods have been proposed to extrapolate 2D measurements to the 3D dimension. X-ray ,CT is a recently developed imaging tool to appreciate 3D architecture. Recently the use of 2D histomorphometric measurements have been shown to provide discordant results compared with 3D values obtained directly. Material and Methods: Seventy human bone biopsies were removed from patients presenting with metabolic bone diseases. Complete bone biopsies were examined by ,CT. Bone volume (BV/TV), Tb.Th, and Tb.Sp were measured on the 3D models. Tb.Th and Tb.Sp were measured by a method based on the sphere algorithm. In addition, six images were resliced and transferred to an image analyzer: bone volume and trabecular characteristics were measured after thresholding of the images. Bone cores were embedded undecalcified; histological sections were prepared and measured by routine histomorphometric methods providing another set of values for bone volume and trabecular characteristics. Comparison between the different methods was done by using regression analysis, Bland-Altman, Passing-Bablock, and Mountain plots. Results: Correlations between all parameters were highly significant, but ,CT overestimated bone volume. The osteoid volume had no influence in this series. Overestimation may have been caused by a double threshold used in ,CT, giving trabecular boundaries less well defined than on histological sections. Correlations between Tb.Th and Tb.Sp values obtained by 3D or 2D measurements were lower, and 3D analysis always overestimated thickness by ,50%. These increases could be attributed to the 3D shape of the object because the number of nodes and the size of the marrow cavities were correlated with 3D values. Conclusion: In clinical practice, ,CT seems to be an interesting method providing reliable morphometric results in less time than conventional histomorphometry. The correlation coefficient is not sufficient to study the agreement between techniques in histomorphometry. The architectural descriptors are influenced by the algorithms used in 3D. [source] Volumetric bone mineral density is an important tool when interpreting bone mineralization in healthy childrenACTA PAEDIATRICA, Issue 2 2009Susanne Eriksson Abstract In adults, it is well known that gender influences bone mass, but studies in children have shown contradictory results. Also, conflicting results have been reported regarding bone mineral density in obese children. Objective: To investigate bone parameters in healthy 8-year-old children and relate them to anthropometry and self-reported physical activity (PA). Design: Bone measurements were performed with dual X-ray absorptiometry in 96 children, and questionnaires were used to assess self-reported PA. Results: Bone mineral content and density differed by gender. Eighteen percent of the children were overweight/obese and they had higher bone mineral content and density than children with normal weight. Bone mineral apparent density (g/cm3) of the lumbar spine did not differ, since the vertebral size differed, as was also the case between genders. Self-reported weight-bearing PA influenced bone mass in the hip. Conclusion: PA influenced bone mineralization at this age. The differences in bone mineral content and density in healthy children would mainly be explained by the differences in bone size, reflected in body height and the width of the vertebrae. This indicates the importance of determining volumetric bone mineralization in children. [source] Low Plasma Vitamin B12 Is Associated With Lower BMD: The Framingham Osteoporosis StudyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2005Katherine L Tucker Abstract Vitamin B12 is important to DNA synthesis and may affect bone formation. We examined the association between this vitamin and BMD in 2576 adults. Men with plasma B12 < 148 pM had significantly lower BMD at the hip, and women at the spine, relative to those with higher B12, and trends were similar for both at all sites. Low vitamin B12 may be a risk factor for low BMD. Introduction: Vitamin B12 is important to DNA synthesis and may affect bone formation. It has been linked to osteoblastic activity in clinical studies and cell culture. Materials and Methods: We examined the relationship between plasma vitamin B12 status and BMD in 2576 adult participants in the Framingham Offspring Osteoporosis Study (1996,2001). BMD was measured by DXA at the hip and spine. Plasma vitamin B12 was measured by radioassay. Mean BMD measures were estimated for four categories of vitamin B12 concentration, based on commonly used cut-offs, using analysis of covariance, adjusted for age, BMI, physical activity score for the elderly (PASE), alcohol use, smoking status, total calcium and vitamin D intake, season of bone measurement, and for women, menopause status and current estrogen use. Further adjustment for protein intake and total homocysteine concentration was also performed. Results: Both men and women with vitamin B12 concentrations <148 pM had lower average BMD than those with vitamin B12 above this cut-off. These differences were significant (p < 0.05) for men at most hip sites and for women at the spine. Significance remained after further adjustment for protein intake and plasma homocysteine. Conclusions: Vitamin B12 deficiency may be an important modifiable risk factor for osteoporosis. [source] Sexual dimorphism in limb bones of ibex (Capra ibex L.): mixture analysis applied to modern and fossil dataINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2007H. Fernández Abstract Estimating sex ratios of fossil bone assemblages is an important step in the determination of demographic profiles, which are essential for understanding the palaeobiology and palaeoethology of any particular species, as well as its exploitation patterns by humans. This is especially true for ibex (Capra ibex), which was a main source of food for hominids during Pleistocene times. Classical methods for determining sexual dimorphism and sex ratio, such as analyses using uni- and bivariate plots, are based on an arbitrary fixing of limits between sexes. Here we use a more robust statistical method termed mixture analysis (MA) to determine the sex of postcranial remains (long bones, metapodials and tarsals) from ibex. For the first time, we apply MA to both a modern and a fossil sample of one species, by using metric data taken from (i) a collection of present-day ibex skeletons and (ii) a Palaeolithic sample of the same species. Our results clearly show that the forelimb (humerus and radius) is more dimorphic than the hindlimb (femur and tibia) and is therefore better suited for sexing ibex. It also appears that metapodials should be used carefully for estimating sex ratios. On the basis of these results, we propose a classification of bone measurements that are more or less reliable for sexing ibex. The results of MA applied to the ibex fossil bones from the Upper Palaeolithic site of the Observatoire (Monaco) lead us to the conclusion that this assemblage consists of a majority of males. The quantitative estimations calculated by the MA make it possible to compare the size of Pleistocene and modern ibex for the whole set of variables used in this study. Copyright © 2006 John Wiley & Sons, Ltd. [source] Bone remodelling following a lower leg fracture in the 11,000-year-old hunter-gatherer from Vado all' Arancio (Italy)INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2002B. M. Holt Abstract The Upper Palaeolithic skeleton from Vado all'Arancio (Italy), dated to about 11,330 BP, exhibits a severe ankle fracture healed with residual deformation. Following recovery, this young hunter-gatherer continued to walk for an extended period of time, albeit in a mechanically altered manner. While right-left differences in external lower limb bone measurements are relatively low, biomechanical analysis of femur and tibia indicates unusually pronounced asymmetry in all cross-sectional measures of diaphyseal strength. Asymmetry results primarily from normal side endosteal hypertrophy, and not from hypotrophy of the injured limb, suggesting that this individual resumed active life following recovery. This pattern of asymmetry underscores the role of physical activity in maintaining bone mass. Copyright © 2002 John Wiley & Sons, Ltd. [source] Association with replication between estrogen-related receptor , (ESRR,) Polymorphisms and bone phenotypes in women of European ancestryJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2010Latifa Elfassihi Abstract Osteoporosis is a bone disease characterized by low bone mineral density (BMD), a highly heritable polygenic trait. Women are more prone than men to develop osteoporosis owing to a lower peak bone mass and accelerated bone loss at menopause. Lack of estrogen thus is a major risk factor for osteoporosis. In addition to having strong similarity to the estrogen receptor 1 (ESR1), the orphan nuclear estrogen-related receptor , (ESRR,) is widely expressed and shows overlap with ESR1 expression in tissues where estrogen has important physiologic functions. For these reasons, we have undertaken a study of ESRR, sequence variants in association with bone measurements [heel quantitative ultrasound (QUS) by measurements of broadband ultrasound attenuation (BUA), speed of sound (SOS), and stiffness index (SI) and dual-energy X-ray absorptiometry (DXA) at the femoral neck (FN) and lumbar spine (LS)]. A silent variant was found to be associated with multiple bone measurements (LS, BUA, SOS, and SI), the p values ranging from .006 to .04 in a sample of 5144 Quebec women. The region of this variant was analyzed using the HapMap database and the Gabriel method to define a block of 20,kb. Using the Tagger method, eight TagSNPs were identified and genotyped in a sample of 1335 women. Four of these SNPs capture the five major block haplotypes. One SNP (rs2818964) and one haplotype were significantly associated with multiple bone measures. All SNPs involved in the associations were analyzed in two other sample sets with significant results in the same direction. These results suggest involvement of ESRR, in the determination of bone density in women. © 2010 American Society for Bone and Mineral Research [source] A controlled re-entry study on the effectiveness of bovine porous bone mineral used in combination with a collagen membrane of porcine origin in the treatment of intrabony defects in humansJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2000Paulo M. Camargo Abstract Aim: The purpose of this study was to evaluate the clinical effectiveness of a bovine porous bone mineral used in combination with a porcine derived collagen membrane as a barrier in promoting periodontal regeneration in intrabony defects in humans. Material and Methods: The study employed a split-mouth design. 22 paired intrabony defects were treated and surgically re-entered 6 months after treatment. Experimental sites were grafted with bovine porous bone mineral and received a collagen membrane for guided tissue regeneration. Control sites were treated with an open flap debridement. Results: Preoperative pocket depths, attachment levels and trans-operative bone measurements were similar for control and experimental sites. Post surgical measurements revealed a significantly greater reduction in pocket depth (differences of 1.89±0.31 mm on buccal 0.88±0.27 mm on lingual measurements) and more gain in clinical attachment (differences of 1.51±0.33 mm on buccal and 1.50±0.35 mm on lingual measurements) in experimental sites. Surgical reentry of the treated defects revealed a significantly greater amount of defect fill in favor of experimental sites (differences of 2.67±0.91 mm on buccal and 2.54±0.87 mm on lingual measurements). Conclusions: The results of this study indicate that clinical resolution of intrabony defects can be achieved using a combination of bovine porous bone mineral and an absorbable, porcine derived collagen membrane when employing a technique based on the principles of guided tissue regeneration. The nature of the attachment between the newly regenerated tissue and the root surfaces needs to be evaluated histologically to confirm the presence of new attachment. [source] In vivo ultra-high-field magnetic resonance imaging of trabecular bone microarchitecture at 7 TJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2008Roland Krug PhD Abstract Purpose To investigate the feasibility of 7T magnetic resonance imaging (MRI) to visualize and quantify trabecular bone structure in vivo by comparison with 3T MRI and in vivo three-dimensional (3D) high-resolution peripheral quantitative computed tomography (HR-pQCT). Materials and Methods The distal tibiae of 10 healthy volunteers were imaged. Therefore, fully balanced steady state free precession (bSSFP) and spin-echo (bSSSE) pulse sequences were implemented and optimized for 7T. Structural bone parameters, such as apparent bone-volume over total-volume fraction (app.BV/TV), apparent trabecular plate separation (app.TbSp), apparent trabecular plate thickness (app.TbTh), and apparent trabecular plate number (app.TbN), were derived. Results All structural trabecular bone parameters correlated well (r > 0.6) between 7T and 3T, and between 7T and HR-pQCT (r > 0.69), with the exception of app.TbTh, which correlated modestly (r = 0.41) between field strengths and very low with HR-pQCT (r < 0.16). Regarding absolute values, app.TbN varied only 4% between field strengths, and only 0.6% between 7T and HR-pQCT. App.TbSp correlated best between 7T and HR-pQCT (r = 0.89). Using bSSSE, significant smaller trabecular thickness and significant higher trabecular number were found compared to bSSFP. Conclusion We concluded that imaging and quantification of the trabecular bone architecture at 7T is feasible and preferably done using bSSSE. There exists great potential for ultra-high-field (UHF) MRI applied to trabecular bone measurements. J. Magn. Reson. Imaging 2008;27:854,859. © 2008 Wiley-Liss, Inc. [source] Total body bone measurements: A cross-sectional study in children with acute lymphoblastic leukemia during and following completion of therapyPEDIATRIC BLOOD & CANCER, Issue 1 2009Kara M. Kelly MD Abstract Background Abnormalities in bone mineral density (BMD) occur in children treated for acute lymphoblastic leukemia (ALL). However, BMD estimates have been performed using varied instruments, reference data, and interpretations. This exploratory cross sectional study to evaluate bone mass in children with ALL, uses an algorithm that serially adjusts for variables known to affect pediatric bone measures by dual energy X-ray absorptiometry (DXA), based on models developed in 1,218 healthy children and adolescents. Procedure Anthropometry, DXA scans, and factors with possible influence on bone mass were evaluated in 21 ALL patients receiving chemotherapy and 20 in the follow-up phase. Main outcome was treatment group differences in Z -scores for total body bone mineral content (BMC), bone area (Area), and areal BMD (aBMD). Results Mean Z -scores for the entire study population for BMC, Area, and aBMD were significantly less than zero. Among possible contributing factors, only calcium intake was a significant co-variate. Comparison between treatment groups showed that least-square mean Z -scores for patients on-therapy for at least 12 months were significantly lower than those off therapy for at least 12 months (P: 0.0008,0.044), except for BMC at last step of the algorithm (adjusted for sex, age, ethnicity, height, weight, and bone area). Conclusions Evaluation of total body DXA by this algorithm is consistent with better general bone status in those off-therapy. However, in this small exploratory study, the lack of significant difference between Z -scores for fully adjusted BMC in on- versus off-therapy groups suggests possible risk of low peak bone mass. Additional longitudinal evaluation is warranted. Pediatr Blood Cancer 2009;52:33,38. © 2008 Wiley-Liss, Inc. [source] A possible link between the pubertal growth of girls and breast cancer in their daughtersAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2008David J.P. Barker One hypothesis for the origins of breast cancer is that it is initiated by exposure of developing breast tissue in utero to maternal sex hormones. The sex hormone profile is established at puberty, when it regulates growth of the pelvic bones. The pubertal growth of girls is characterized by broadening and rounding of the pelvis. The maximal width between their iliac crests, the intercristal width, increases more rapidly than in boys. We hypothesized that higher sex hormone concentrations at puberty produce larger intercristal widths, and these are markers of increased breast cancer risk in the next generation. We followed up 6,370 women who were born in Helsinki during 1934,1944, and whose mothers' pelvic bones were measured during routine antenatal care. Women whose mothers had large intercristal widths had higher rates of breast cancer. In those born at or after 40 weeks gestation, the hazard ratio for breast cancer was 3.7 (95% CI: 2.1,6.6) if their mother's intercristal width was greater than 30 cm. Among women born to multiparous mothers this hazard ratio rose to 7.2 (3.4,15.4). Hazard ratios for breast cancer were also higher in the daughters of mothers with round iliac crests. Pelvic bone measurements which increase similarly in girls and boys at puberty did not predict breast cancer. We conclude that the intercristal width, and the roundness of the iliac crests, are markers of mothers' sex hormones, and postulate that high concentrations cause genetic instability in differentiating breast cells in their daughters in utero. Am. J. Hum. Biol., 2008. © 2007 Wiley-Liss, Inc. [source] Skeletal health: primate model of postmenopausal osteoporosisAMERICAN JOURNAL OF PRIMATOLOGY, Issue 9 2009S.Y. Smith Abstract Currently, the nonhuman primate is the most widely used large animal model to evaluate the safety and efficacy of new drug entities to treat or prevent estrogen-deficiency-induced bone loss and osteoporosis. Surgical ovariectomy (OVX) induces a state of high bone turnover and rapid bone loss establishing a new steady-state bone mass within 8,9 months. Many systems in the monkey are similar to humans, including skeletal and reproductive physiology and the immune system, making this a plausible model suitable to evaluate the effects of new bone drugs. The long-term sequelae following OVX and withdrawal of monthly exposure to cyclic reproductive hormones in older female monkeys (cynomolgus and rhesus) mimics estrogen depletion and postmenopausal bone loss occurring in women. Characterization of the primate model revealed an apparent limitation to the extent of bone loss. Animals lose bone mass after OVX, but the extent of the bone loss cannot be described as osteoporotic. The small differences between OVX and sham-operated controls in many important bone measurements is overcome by including 15,20 animals per group to provide adequate statistical power. The long-term, at least 16 month, bone safety studies performed to satisfy regulatory guidelines provide an opportunity to study treatment effects for an extended period not covered in shorter-term safety studies. In vivo end-points such as densitometry and biochemical markers translate easily to clinical use, while biomechanical end-points that cannot be measured clinically can be used to predict fracture prevention. To date, the monkey OVX model has been used to support submissions for many new drugs including anabolics, bisphosphonates and selective estrogen receptor modulators. Despite its limitations, the OVX monkey model remains the best characterized of the large animal models of osteopenia and has become integral to osteoporosis drug development. Am. J. Primatol. 71:752,765, 2009. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||