title: Deterioration of trabecular plate-rod and cortical microarchitecture and reduced bone stiffness at distal radius and tibia in postmenopausal women with vertebral fractures.
abstract: Postmenopausal women with vertebral fractures have abnormal bone microarchitecture at the distal radius and tibia by HR-pQCT, independent of areal BMD. However, whether trabecular plate and rod microarchitecture is altered in women with vertebral fractures is unknown. This study aims to characterize the abnormalities of trabecular plate and rod microarchitecture, cortex, and bone stiffness in postmenopausal women with vertebral fractures. HR-pQCT images of distal radius and tibia were acquired from 45 women with vertebral fractures and 45 control subjects without fractures. Trabecular and cortical compartments were separated by an automatic segmentation algorithm and subjected to individual trabecula segmentation (ITS) analysis for measuring trabecular plate and rod morphology and cortical bone evaluation for measuring cortical thickness and porosity, respectively. Whole bone and trabecular bone stiffness were estimated by finite element analysis. Fracture and control subjects did not differ according to age, race, body mass index, osteoporosis risk factors, or medication use. Women with vertebral fractures had thinner cortices, and larger trabecular area compared to the control group. By ITS analysis, fracture subjects had fewer trabecular plates, less axially aligned trabeculae and less trabecular connectivity at both the radius and the tibia. Fewer trabecular rods were observed at the radius. Whole bone stiffness and trabecular bone stiffness were 18% and 22% lower in women with vertebral fractures at the radius, and 19% and 16% lower at the tibia, compared with controls. The estimated failure load of the radius and tibia were also reduced in the fracture subjects by 13% and 14%, respectively. In summary, postmenopausal women with vertebral fractures had both trabecular and cortical microstructural deterioration at the peripheral skeleton, with a preferential loss of trabecular plates and cortical thinning. These microstructural deficits translated into lower whole bone and trabecular bone stiffness at the radius and tibia. Our results suggest that abnormalities in trabecular plate and rod microstructure may be important mechanisms of vertebral fracture in postmenopausal women.
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: jw2857@columbia.edu.
authors.forename: Ji
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, USA. Electronic address: es2029@cumc.columbia.edu.
authors.forename: Emily M
authors.initials: EM
authors.lastname: Stein
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: bz2159@columbia.edu.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, USA. Electronic address: kn2205@cumc.columbia.edu.
authors.forename: Kyle K
authors.initials: KK
authors.lastname: Nishiyama
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: yy2407@columbia.edu.
authors.forename: Y Eric
authors.initials: YE
authors.lastname: Yu
authors.affiliation: Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, NY, USA. Electronic address: es54@cumc.columbia.edu.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Shane
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: exg1@columbia.edu.
authors.forename: X Edward
authors.initials: XE
authors.lastname: Guo
mesh_terms: D015502:Absorptiometry, Photon; D000368:Aged; D001696:Biomechanical Phenomena; D015519:Bone Density; D000071556:Cancellous Bone / Q000473:pathology / Q000503:physiopathology; D016022:Case-Control Studies; D000071538:Cortical Bone / Q000473:pathology / Q000503:physiopathology; D005260:Female; D020342:Finite Element Analysis; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016015:Logistic Models; D017698:Postmenopause / Q000502:physiology*; D011884:Radius / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed
keywords: Bone microarchitecture; High-resolution peripheral quantitative computed tomography; Individual trabecula segmentation; Trabecular plate and rod; Vertebral fracture