title: Noninvasive Assessment of Skeletal Microstructure and Estimated Bone Strength in Hypoparathyroidism.
abstract: In hypoparathyroidism, areal bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) is above average, and skeletal indices by bone biopsy are abnormal. We used high-resolution peripheral quantitative computed tomography (HRpQCT) and finite element analyses (FEA) to further investigate skeletal microstructure and estimated bone strength. We studied 60 hypoparathyroid subjects on conventional therapy using DXA, HRpQCT, and FEA of the distal radius and tibia compared with normative controls from the Canadian Multicentre Osteoporosis Study. In hypoparathyroid women and men, areal BMD was above average at the lumbar spine and hip sites by DXA; radial BMD was also above average in hypoparathyroid women. Using HRpQCT, cortical volumetric BMD was increased in the hypoparathyroid cohort compared with controls at both the radius and tibia. Cortical porosity was reduced at both sites in pre- and postmenopausal women and at the tibia in young men with a downward trend at the radius in men. At the tibia, trabecular number was increased in premenopausal women and men and trabecular thickness was lower in women. Ultimate stress and failure load at both sites for the hypoparathyroid subjects were similar to controls. Using a linear regression model, at both radius and tibia, each increment in age decreased ultimate stress and failure load, whereas each increment in duration of hypoparathyroidism increased these same indices. These results provide additional evidence for the critical role of parathyroid hormone in regulating skeletal microstructure. Longer disease duration may mitigate the adverse effects of age on estimated bone strength in hypoparathyroidism.
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Natalie E
authors.initials: NE
authors.lastname: Cusano
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Kyle K
authors.initials: KK
authors.lastname: Nishiyama
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Chengchen
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Mishaela R
authors.initials: MR
authors.lastname: Rubin
authors.affiliation: INSERM UMR 1033, Hôpital Edouard Herriot, Université de Lyon, Lyon, France.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Boutroy
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: McMahon
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA.
authors.forename: X Edward
authors.initials: XE
authors.lastname: Guo
authors.affiliation: Department of Medicine, Division of Endocrinology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
authors.forename: John P
authors.initials: JP
authors.lastname: Bilezikian
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D015519:Bone Density; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000378:metabolism; D006801:Humans; D007011:Hypoparathyroidism / Q000000981:diagnostic imaging / Q000378:metabolism; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D011884:Radius / Q000000981:diagnostic imaging / Q000378:metabolism
keywords: BONE MICROARCHITECTURE; HIGH-RESOLUTION PERIPHERAL QUANTITATIVE COMPUTED TOMOGRAPHY (HRpQCT); HYPOPARATHYROIDISM