95 research outputs found

    Vertebral fractures are associated with increased cortical porosity in iliac crest bone biopsy of men with idiopathic osteoporosis

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    In men, vertebral fractures are poorly associated with bone density, and both cortical and trabecular micro-architectural changes could contribute to bone fragility. Bone histomorphometry makes it possible to investigate both the thickness and porosity of cortical bone, which has been reported to have a major impact on the biomechanical properties of bone. We therefore conducted a cross sectional study using iliac crest biopsies to investigate the trabecular and cortical bone structure in men with or without vertebral fractures.We selected 93 bone biopsies from men with idiopathic osteoporosis (defined as a T-score <− 2.5), between 40 and 70 years of age. Patients were divided into two groups on the basis of the presence (n = 46) or absence (n = 47) of prevalent vertebral fracture (VFX). We measured micro-architectural indices in trabecular and cortical bone by histomorphometry at the iliac crest. Patients with VFX had lower trabecular bone volume (BV/TV: 12.4 ± 3.8 versus 14.7 ± 3.1 % (m ± SD)), p < 0.01), higher trabecular separation (Tb.Sp: 871 ± 279 versus 719 ± 151 Όm, p < 0.01), and higher marrow star volume (V*m.space: 1.617 ± 1.257 versus 0.945 ± 0.466 mm3, p < 0.01). Cortical thickness (Ct.Th) was the same in patients with or without VFX, whereas cortical porosity (Ct.Po) was higher in patients with VFX (6.5 ± 2.6 versus 5.0 ± 2.0 %, p < 0.01), because their Haversian canals had higher mean areas (8291 ± 4135 versus 5438 ± 2809 Όm2, p < 0.001). There was no correlation between any trabecular and cortical micro-architectural parameters. Using a logistic regression model, we evaluated the VFX as a function of the V⁎m.space and Ct.Po, adjusted for age. The odds-ratio of having a VFX was 3.89 (95% CI 1.19–12.7, p = 0.02) for the third tertile of V*m.space (adjusted on age and Ct.Po), and 4.07 (95% CI 1.25–13.3, p = 0.02) for the third tertile of Ct.Po (adjusted on age and V*m.space). Our data show that both trabecular and cortical bone microarchitecture contribute independently to vertebral fractures in men with idiopathic osteoporosis. In contrast to data reported in women, in men it is cortical porosity, and not cortical width, that is associated with vertebral fractures. This suggests that the cortical deficit is different in men and in women with fragility fractures

    Osteoporosis in young adults: pathophysiology, diagnosis, and management

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    Postmenopausal osteoporosis is mainly caused by increased bone remodeling resulting from estrogen deficiency. Indications for treatment are based on low areal bone mineral density (aBMD, T-score ≀ −2.5), typical fragility fractures (spine or hip), and more recently, an elevated 10-year fracture probability (by FRAXÂź). In contrast, there is no clear definition of osteoporosis nor intervention thresholds in younger individuals. Low aBMD in a young adult may reflect a physiologically low peak bone mass, such as in lean but otherwise healthy persons, whereas fractures commonly occur with high-impact trauma, i.e., without bone fragility. Furthermore, low aBMD associated with vitamin D deficiency may be highly prevalent in some regions of the world. Nevertheless, true osteoporosis in the young can occur, which we define as a T-score below −2.5 at spine or hip in association with a chronic disease known to affect bone metabolism. In the absence of secondary causes, the presence of fragility fractures, such as in vertebrae, may point towards genetic or idiopathic osteoporosis. In turn, treatment of the underlying condition may improve bone mass as well. In rare cases, a bone-specific treatment may be indicated, although evidence is scarce for a true benefit on fracture risk. The International Osteoporosis Foundation (IOF) convened a working group to review pathophysiology, diagnosis, and management of osteoporosis in the young, excluding children and adolescents, and provide a screening strategy including laboratory exams for a systematic approach of this conditio

    Electrical Impedance of Acupuncture Meridians: The Relevance of Subcutaneous Collagenous Bands

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    Background: The scientific basis for acupuncture meridians is unknown. Past studies have suggested that acupuncture meridians are physiologically characterized by low electrical impedance and anatomically associated with connective tissue planes. We are interested in seeing whether acupuncture meridians are associated with lower electrical impedance and whether ultrasound-derived measures – specifically echogenic collagenous bands- can account for these impedance differences. Methods/Results: In 28 healthy subjects, we assessed electrical impedance of skin and underlying subcutaneous connective tissue using a four needle-electrode approach. The impedances were obtained at 10 kHz and 100 kHz frequencies and at three body sites- upper arm (Large Intestine meridian), thigh (Liver), and lower leg (Bladder). Meridian locations were determined by acupuncturists. Ultrasound images were obtained to characterize the anatomical features at each measured site. We found significantly reduced electrical impedance at the Large Intestine meridian compared to adjacent control for both frequencies. No significant decrease in impedance was found at the Liver or Bladder meridian. Greater subcutaneous echogenic densities were significantly associated with reduced impedances in both within-site (meridian vs. adjacent control) and between-site (arm vs. thigh vs. lower leg) analyses. This relationship remained significant in multivariabl

    Somatostatin analogues in the treatment of gastroenteropancreatic neuroendocrine tumours, current aspects and new perspectives

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    Gastroenteropancreatic neuroendocrine tumours (GEP NETs) are rare tumours that present many clinical features

    Gastrointestinal symptoms and association with medication use patterns, adherence, treatment satisfaction, quality of life, and resource use in osteoporosis: baseline results of the MUSIC-OS study

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    Summary: The Medication Use Patterns, Treatment Satisfaction, and Inadequate Control of Osteoporosis Study (MUSIC-OS) is a prospective, observational study of women with osteoporosis in Europe and Canada. At baseline, patients with gastrointestinal symptoms reported lower adherence to osteoporosis treatment, treatment satisfaction, and health-related quality of life, than those without gastrointestinal symptoms. Introduction: The aim of the study was to examine gastrointestinal (GI) symptoms and the association between GI symptoms and treatment adherence, treatment satisfaction, and health-related quality of life (HRQoL) among osteoporotic women in Europe and Canada. Methods: Baseline results are reported here for a prospective study which enrolled postmenopausal, osteoporotic women who were initiating (new users) or continuing (experienced users) osteoporosis treatment at study entry (baseline). A patient survey was administered at baseline and included the occurrence of GI symptoms during 6-month pre-enrolment, treatment adherence (adherence evaluation of osteoporosis (ADEOS), score 0–22), treatment satisfaction (Osteoporosis Treatment Satisfaction Questionnaire for Medications (OPSAT-Q), score 0–100) and HRQoL (EuroQol-5 dimension (EQ-5D) utility, score 0–1; OPAQ-SV, score 0–100). The association between GI symptoms and ADEOS (experienced users), OPSAT-Q (experienced users), and HRQoL (new and experienced users) was assessed by general linear models adjusted for patient characteristics. Results: A total of 2959 patients (2275 experienced and 684 new users) were included. Overall, 68.1 % of patients experienced GI symptoms in the past 6 months. Compared with patients without GI symptoms, patients with GI symptoms had lower mean baseline scores on most measures. The mean adjusted differences were ADEOS, −0.43; OPSAT-Q, −5.68; EQ-5D, −0.04 (new users) and −0.06 (experienced users), all P < 0.01. GI symptoms were also associated with lower OPAQ-SV domain scores: physical function, −4.17 (experienced users); emotional status, −4.28 (new users) and −5.68 (experienced users); back pain, −5.82 (new users) and −11.33 (experienced users), all P < 0.01. Conclusions: Patients with GI symptoms have lower treatment adherence and treatment satisfaction and worse HRQoL than patients without GI symptoms

    Heritable sclerosing bone disorders: presentation and new molecular mechanisms.

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    Sclerosing bone disorders can be subdivided according to their clinical presentation, the primarily affected cell type, and the cellular pathways. Osteoclast-rich osteopetrosis and related disorders have been related in most cases to mutations in genes required for osteoclast function. More recently, osteoclast-poor forms of osteopetrosis have been described as being connected to factors that govern osteoclast differentiation. However, increased bone formation can also cause osteosclerosis. Camurati-Engelman disease and osteopoikilosis are both related transforming growth factor-beta signaling. Rare recessive or dominant sclerosing disorders, such as endosteal hyperostosis, sclerosteosis, van Buchem disease, high bone-mass syndrome, and osteopathia striata, are caused by mutations in genes involved in the Wnt pathway, which regulates osteoblast differentiation. Finally, a third entity, including Ghosal syndrome and pachydermoperiostosis, is related to mutations in genes of the eicosanoid pathway. Clinical aspects and the consequences for our understanding of bone biology are discussed

    Evaluation of Cortical Porosity from HR-pQCT at the Tibia: Comparison with Synchrotron Radiation Micro-computed Tomograph

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    International audienceThe HR-pQCT (XtremeCT ScancoŸ) with a voxel size at 82 (”m3) is carried out routinely in clinical research protocols. Micro-computed tomography (micro-CT) has become a standard tool for examination of trabecular and cortical bone in 3 dimensions (3D).The purpose of this study is to evaluate the accuracy and precision of cortical measurements derived from HR-pQCT images using a local comparison with morphological measurements from synchrotron radiation (SR) micro-CT.Thirty tibias specimens (mean age 82.2±9.7) were scanned at 3.5 cm from the tibial pilon. The acquisition and analysis protocols provided by the manufacturer were used. Fourteen samples were scanned twice to calculate the Root Mean Square Coefficient of Variation (RMSCV,%). The usual outcomes include: volumetric bone density (gHA/cm3) for entire (Dtot) and cortical (Dcomp) regions, cortical thickness (Ct.Th,mm). New features as cortical porosity (Ct.Po) and mean pore diameter (mPo.Dm) were measured with manual correction of the endosteal contour. In a site matched region of HR-pQCT images, bone samples were taken at the posterior part of the tibia and imaged on beamline ID19 (ESRF,Grenoble). The acquisition parameters used were 30 keV, 3500 views over 360°, the exposure time for each view was 0.3s. The voxel size is 7.5 (”m3). Ct.Th_SR was manually measured. A unique threshold was used for the whole dataset. Using the CTAn SkyscanŸ software, the following parameters were obtained: Pore volume/Bone volume (PoV/TV_SR %), pore diameter (Po.Dm_SR,mm), pore spacing (Po.Sp_SR,mm), pore number (Po.N_SR,mm-1) and the degree of anisotropy (DA,no unit). Maps of linear attenuation coefficient were converted into degrees of mineralization of bone (DMB) with data expressed in g/cm3.Pearson correlation coef. (r) between Ct.Th vs Ct.Th_SR was r=0.58**. Correlation coef. were not significant for Dcomp vs DMB and for m.Po.Dm vs Po.Dm_SR and PoV/TV_SR. Significant correlation coef. between PoV/TV_SR and cortical parameters from HR-pQCT are shown in Table 1.To explain Dcomp in multivariate analysis, the determination coef (r2) was 0.80 with a combination of PoV/TV_SR, Po.N_SR and Po.Sp_SR instead of 0.77 with PoV/TV_SR alone.In conclusion, Dcomp from HR-pQCT images is the most pertinent parameter reflecting with a good precision cortical porosity measured from SR micro-CT images. Dcomp was not better explained by a combination of morphological parameters from SR micro-CT images
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