title: TBS reflects trabecular microarchitecture in premenopausal women and men with idiopathic osteoporosis and low-traumatic fractures.
abstract: Transiliac bone biopsies, while widely considered to be the standard for the analysis of bone microstructure, are typically restricted to specialized centers. The benefit of Trabecular Bone Score (TBS) in addition to areal bone mineral density (aBMD) for fracture risk assessment has been documented in cross-sectional and prospective studies. The aim of this study was to test if TBS may be useful as a surrogate to histomorphometric trabecular parameters of transiliac bone biopsies. Transiliac bone biopsies from 80 female patients (median age 39.9 years-interquartile range, IQR 34.7; 44.3) and 43 male patients (median age 42.7 years-IQR 38.9; 49.0) with idiopathic osteoporosis and low traumatic fractures were included. Micro-computed tomography values of bone volume fraction (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), structural model index (SMI) as well as serum bone turnover markers (BTMs) sclerostin, intact N-terminal type 1 procollagen propeptide (P1NP) and cross-linked C-telopeptide (CTX) were investigated. TBS values were higher in females (1.282 vs 1.169, p< 0.0001) with no differences in spine aBMD, whereas sclerostin levels (45.5 vs 33.4 pmol/L) and aBMD values at the total hip (0.989 vs 0.971 g/cm(2), p<0.001 for all) were higher in males. Multiple regression models including: gender, aBMD and BTMs revealed TBS as an independent, discriminative variable with adjusted multiple R(2) values of 69.1% for SMI, 79.5% for Tb.N, 68.4% for Tb.Sp, and 83.3% for BV/TV. In univariate regression models, BTMs showed statistically significant results, whereas in the multiple models only P1NP and CTX were significant for Tb.N. TBS is a practical, non-invasive, surrogate technique for the assessment of cancellous bone microarchitecture and should be implemented as an additional tool for the determination of trabecular bone properties.
authors.affiliation: St. Vincent Hospital, Medical Department II, Academic Teaching Hospital of the Medical University of Vienna, Austria. Electronic address: christian.muschitz@bhs.at.
authors.forename: Christian
authors.initials: C
authors.lastname: Muschitz
authors.affiliation: St. Vincent Hospital, Medical Department II, Academic Teaching Hospital of the Medical University of Vienna, Austria.
authors.forename: Roland
authors.initials: R
authors.lastname: Kocijan
authors.affiliation: St. Vincent Hospital, Medical Department II, Academic Teaching Hospital of the Medical University of Vienna, Austria.
authors.forename: Judith
authors.initials: J
authors.lastname: Haschka
authors.affiliation: Institute of Lightweight Design and Structural Biomechanics, Vienna University of Technology, Vienna, Austria.
authors.forename: Dieter
authors.initials: D
authors.lastname: Pahr
authors.affiliation: Center for Medical Statistics, Informatics and Intelligent Systems, The Medical University of Vienna, Austria.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Kaider
authors.affiliation: Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Pietschmann
authors.affiliation: Center of Bone Diseases, Lausanne University Hospital Switzerland.
authors.forename: Didier
authors.initials: D
authors.lastname: Hans
authors.affiliation: Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria.
authors.forename: Gabriela Katharina
authors.initials: GK
authors.lastname: Muschitz
authors.affiliation: Department of Internal Medicine, Division of Endocrinology and Metabolism, The Medical University of Graz, Austria.
authors.forename: Astrid
authors.initials: A
authors.lastname: Fahrleitner-Pammer
authors.affiliation: St. Vincent Hospital, Medical Department II, Academic Teaching Hospital of the Medical University of Vienna, Austria.
authors.forename: Heinrich
authors.initials: H
authors.lastname: Resch
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008297:Male; D010024:Osteoporosis / Q000150:complications / Q000000981:diagnostic imaging*; D058866:Osteoporotic Fractures / Q000000981:diagnostic imaging*; D017697:Premenopause; D055114:X-Ray Microtomography
keywords: Bone microarchitecture; Bone turnover marker; Bone μCT; Idiopathic osteoporosis; Trabecular bone score