The relationship between serum vitamin D concentrations andin vivo tetracycline labeling of osteoid in crush fracture osteoporosis

Summary Twenty of 22 consecutive British patients with crush fracture osteoporosis had transiliac bone biopsies following doublein vivo tetracycline labeling synchronized with the collection of serum for the measurement of vitamin D metabolites. A significant but direct (rather than inverse) relationship was found between 25-hydroxyvitamin D (calcidiol) levels and the fraction of cancellous surfaces covered with osteoid not taking either tetracycline label (r=0.53,P<0.02). There was no correlation with 1,25-dihydroxyvitamin D levels. No patient had frankly thickneded osteoid seams although 3 had reduced but measurable calcidiol levels. These results make it unlikely that the majority of patients with osteoporosis who have osteoid of normal thickness but reduced uptake of tetracycline have a mineralization defect secondary to vitamin D deficiency. The pathophysiological significance of unlabeled osteoid in osteoporosis requires further investigation.     

Epidemiology,treatment and costs of osteoporosis in Germany—the BoneEVA Study

INTRODUCTION: In Germany, accurate data on the prevalence and treatment of osteoporosis, as well as the cost of this illness, are not available. The aim of this study is to give a valid estimation of these items for the year 2003. METHODS: Routine data from a German sickness fund covering 1.5 million beneficiaries and billing data for outpatient visits were used to obtain estimates of prevalence for osteoporosis. Claims data for patients with osteoporosis (M80, M81) or an osteoporosis-related fracture diagnosis (S22, S32, S42, S52, S72, S82) or treatment with anti-osteoporosis drugs were examined. Costs were calculated from the perspective of the German health insurance system and the German nursing care insurance system, respectively. Only direct costs of osteoporosis were considered. RESULTS: In 2003, 7.8 million Germans (6.5 million women) were affected by osteoporosis. Of them, 4.3% experienced at least one clinical fracture. Only 21.7% were treated with an anti-osteoporosis drug. The total direct costs attributable to osteoporosis amounted to euros 5.4 billion. CONCLUSION: This study confirms that osteoporosis is underdiagnosed, undertreated and imposes a considerable economic burden on the health system in Germany. Effective strategies for the prevention and management of this disease are needed.     

Reproducibility of bone mineral density measurements using dual X-ray absorptiometry in daily clinical practice

Bone mineral density (BMD) measurements are frequently performed repeatedly for each patient. Subsequent BMD measurements allow reproducibility to be assessed. Previous studies have suggested that reproducibility may be influenced by age and clinical status. The purpose of the study was to examine the reproducibility of BMD by dual energy X-ray absorptiometry (DXA) and to investigate the practical value of different measures of reproducibility in three distinct groups of subjects: healthy young volunteers, postmenopausal women and patients with chronic rheumatic diseases. Two hundred twenty-two subjects underwent two subsequent BMD measurements of the spine and hip. There were 60 young healthy subjects, 102 postmenopausal women and 60 patients with chronic rheumatic diseases (33 rheumatoid arthritis, 10 ankylosing spondylitis and 10 other systemic diseases). Forty-five patients (75%) among the third group were receiving corticosteroids. Reproducibility was expressed as the smallest detectable difference (SDD), coefficient of variation (CV), least significant change (LSC) and intraclass correlation coefficient (ICC). Sources of variation were investigated by linear regression analysis. The median interval between measurements was 0 days (range 0–7). The mean difference (SD) between the measurements (g/cm²) was –0.0001 (±0.003) and –0.0004 (±0.002) at L1-L4 and the total hip, respectively. At L1-L4 and the total hip, SDD (g/cm²) was ±0.04 and ±0.02, CV (%) was 2.02 and 1.29, and LSC (%) 5.60 and 3.56, respectively. The ICC at the spine and hip was 0.99 and 0.99, respectively. Only a minimal difference existed between the groups. Reproducibility in the three groups studied was good. In a repeated DXA scan, a BMD change, the least significant change (LSC) or the SDD should be regarded as significant. Use of the SDD is preferable to use of the CV and LSC because of its independence from BMD and its expression in absolute units. Expressed as SDD, a BMD change of at least ±0.04 g/cm² at L1-L4 and ±0.02 g/cm² at the total hip should be considered significant. This reproducibility seems independent from age and clinical status and improved in the hips by measuring the dual femur.     

骨质疏松骨折血清骨钙素和尿脱氧吡啶酚变化的研究

目的了解骨质疏松骨折患者在骨折愈合过程中骨代谢的变化,更好地指导临床有效的治疗。方法对80例骨折患者愈合过程中血清骨钙素和尿脱氧吡啶酚变化进行观察。结果骨质疏松性骨折后骨钙素呈增高趋势,可超出正常值范围。第3周达到最高峰,第6周逐渐下降到正常值范围;骨质疏松性骨折后尿脱氧吡啶酚亦呈增高趋势,完全超出正常值范围。第6周达到最高峰,第9周逐渐下降但未完全回复正常范围。结论骨质疏松骨折患者早期骨转换都很活跃,血清骨钙素和尿脱氧吡啶酚均增高,尿脱氧吡啶酚的增高较血清骨钙素的增高显著,骨吸收持续影响较大,骨代谢处于失偶联的状态。若早期能有效地控制骨吸收将有利于加强骨形成的能力,最终有利于缩短骨折愈合时间。     

老年月骨无菌性坏死病因学分析

目的　分析 60岁以上月骨无菌性坏死病人的病因学特点。方法　调查 7例病人的患腕关节 ,腕关节第一次疼痛时间为发病年龄 ,应用Dornan标准评估临床结果。基于放射学结果确定本病的发展进程 (参照Lichtman分级 )、尺骨的变化及腕高比。测定血清Ca2 、P3- 值和进行骨密度检查。结果　本病女性发病率高于男性 ,最常见于手工业工人的优势手 ,尺骨负向变异率低。所有病人血清Ca2 、P3- 值与正常同龄人相比无明显差异 (P >0 0 5)。平均骨密度测量结果与同龄正常人相比有显著统计学差异 (P <0 0 1 )。均有腕骨塌陷的放射学表现。结论　老年月骨无菌性坏死的病因学不同于普通的月骨无菌性坏死病人 ,骨质疏松症可能为主要的诱发因素。     

Sex hormones,their receptors and bone health

Sex steroids regulate skeletal maturation and preservation in both men and women, as already recognized in the 1940s by Albright and Reifenstein. The impact of gonadal insufficiency on skeletal integrity has been widely recognized in adult men and women ever since. In the context of their skeletal actions, androgens and estrogens are no longer considered as just male and female hormones, respectively. Androgens can be converted into estrogens within the gonads and peripheral tissues and both are present in men and women, albeit in different concentrations. In the late 1980s, sex steroid receptors were discovered in bone cells. However, the understanding of sex steroid receptor activation and translation into biological skeletal actions is still incomplete. Due to the complex metabolism, sex steroids may have not only endocrine but also paracrine and/or autocrine actions. Also, circulating sex steroid concentrations do not necessarily reflect their biological activity due to strong binding to sex hormone binding globulin (SHBG). Finally, sex steroid signaling may include genomic and non-genomic effects in bone and non-bone cells. This review will focus on our current understanding of gonadal steroid metabolism, receptor activation, and their most relevant cellular and biological actions on bone.     

Age trends in proximal femur geometry in men: variation by race and ethnicity

Summary Data on bone architecture in diverse male populations are limited. We examined proximal femur geometry in 1,190 black, Hispanic, and white men. Cross-sectional analyses indicate greatest bone strength among black men, and greater age-related differences in bone strength among Hispanic men than other subjects at the narrow neck and intertrochanter regions of the proximal femur. Introduction Although race/ethnic differences in bone mass are well-documented, less is known about differences in bone architecture. We examined proximal femur geometry in a diverse, randomly-sampled population of 1,190 community-dwelling men (age 30–79 y). Methods Dual X-ray absorptiometry scans were obtained for 355 black, 394 Hispanic, and 441 white subjects. Measures were obtained for the narrow neck (NN), intertrochanter (IT) and shaft regions of the proximal femur via hip structural analysis. Analyses considered bone mineral density (BMD, g/cm²), outer diameter (cm), cross-sectional area (CSA, cm²), section modulus (Z, cm³), and buckling ratio (BR). Results were adjusted for height, weight and physical activity level. Results Black subjects exhibited greater age-specific BMD, CSA and Z, than their white counterparts. For instance, at age 50 y, NN BMD was approximately 11% higher among black men (p < 0.001). Hispanic men exhibited sharper age-related differences in NN and IT BMD than did others. IT BMD, for instance, decreased by 2.4% with 10 y age among Hispanic subjects, but had virtually no age trend in others (p < 0.001). Conclusions These results imply greater bone strength among black American men than among their white counterparts, and may indicate elevated fracture risk among older Hispanic American subpopulations. Grant support: The BACH/Bone study was supported by grant AG 20727 from the National Institute on Aging (NIA). The parent study (BACH) was supported by grant DK 56842 from the National Institute of Diabetes and Digestive and Kidney Diseases.     

Radial cortical and trabecular bone densities of men and women standardized with the European forearm phantom

We previously showed that it is possible to cross-calibrate peripheral bone densitometers using the European Spine Phantom (ESP). We have now performed a multinational study of cross-calibrated radius bone density based on normal subjects of both sexes in eight European centers. Six centers were equipped with machines made by Scanco or Stratec for determining distal radial trabecular bone density by quantitative computed tomography (QCT) and two were equipped with Lunar SP2 single photon absorptiometry (SPA) equipment for measuring midshaft cortical bone density. Subjects recruited ranged from 20 to over 80 years of age. Over one hundred and fifteen men were studied by QCT and a different cohort of 104 men were studied with SPA; the equivalent figures for women were 235 and 123. Reference ranges were derived for bone density against age for each of the four groups, and their applicability is discussed in relation to between-center differences in the results obtained. There were insignificant differences (P>0.05 with Bonferroni correction) between centers in the values obtained by QCT in the different populations. However, there were considerably larger and highly statistically significant differences between midshaft cortical bone density values of about 10% of overall means between subjects from eastern Finland and central Belgium (P<0.001), with higher Finnish values. Women had considerably lower radial trabecular bone density values than men at all ages, a result that differentiates the radius from the spine. This sex difference widened after menopause. These results have important implications for understanding the contribution of bone density to the differential risk of Colles' fracture in the two sexes and suggest that further work is needed to establish young normal reference ranges for radial bone density in Europe.     

A microtomographic system for the nondestructive evaluation of bone architecture

Microtomography (micro-computed-tomography, μ-CT) is a method to image and quantify trabecular bone. It has the capability to address the role of trabecular architecture on the mechanical properties of bone and to study trabecular bone remodeling. The system described in this work is based on a compact fan-beam type tomograph that can work in spiral scanning or multislice mode. An X-ray tube with a microfocus is used as a source, a CCD-array as a detector. Samples with diameters from a few millimeters to a maximum of 14 mm can be measured, typically, bone biopsies with a diameter of 8 mm and a length of approximately 10 mm are measured. Spatial resolution is 28 μm. Usually the volume of interest contains 4 × 4 × 4 mm³ and is represented in 14 × 14 × 14 μm³ voxels. 3D stereological indices are extracted according to the standard definitions used in histomorphometry. Triangular surface representation is effected with an extended marching cube algorithm and forms a convenient basis for finite element analysis. Microtomographic measurements may be employed to ``calibrate' lower-dose, lower-resolution images in vivo as well as to nondestructively assess unprocessed surgical bone biopsy specimens. These specimens remain intact for mechanical or histological testing. Received: 17 April 1995 / Accepted: 18 August 1995