Abnormal microarchitecture and reduced stiffness at the radius and tibia in postmenopausal women with fractures.
Measurement of areal bone mineral density (aBMD) by dual-energy x-ray absorptiometry (DXA) has been shown to predict fracture risk. High-resolution peripheral quantitative computed tomography (HR-pQCT) yields additional information about volumetric BMD (vBMD), microarchitecture, and strength that may increase understanding of fracture susceptibility. Women with (n = 68) and without (n = 101) a history of postmenopausal fragility fracture had aBMD measured by DXA and trabecular and cortical vBMD and trabecular microarchitecture of the radius and tibia measured by HR-pQCT. Finite-element analysis (FEA) of HR-pQCT scans was performed to estimate bone stiffness. DXA T-scores were similar in women with and without fracture at the spine, hip, and one-third radius but lower in patients with fracture at the ultradistal radius (p < .01). At the radius fracture, patients had lower total density, cortical thickness, trabecular density, number, thickness, higher trabecular separation and network heterogeneity (p < .0001 to .04). At the tibia, total, cortical, and trabecular density and cortical and trabecular thickness were lower in fracture patients (p < .0001 to .03). The differences between groups were greater at the radius than at the tibia for inner trabecular density, number, trabecular separation, and network heterogeneity (p < .01 to .05). Stiffness was reduced in fracture patients, more markedly at the radius (41% to 44%) than at the tibia (15% to 20%). Women with fractures had reduced vBMD, microarchitectural deterioration, and decreased strength. These differences were more prominent at the radius than at the tibia. HR-pQCT and FEA measurements of peripheral sites are associated with fracture prevalence and may increase understanding of the role of microarchitectural deterioration in fracture susceptibility. © 2010 American Society for Bone and Mineral Research.
Stein
Emily M
EM
Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA.
Liu
X Sherry
XS
Nickolas
Thomas L
TL
Cohen
Adi
A
Thomas
Valerie
V
McMahon
Donald J
DJ
Zhang
Chiyuan
C
Yin
Perry T
PT
Cosman
Felicia
F
Nieves
Jeri
J
Guo
X Edward
XE
Shane
Elizabeth
E
D015502:Absorptiometry, Photon; D000368:Aged; D001696:Biomechanical Phenomena; D015519:Bone Density; D005260:Female; D020342:Finite Element Analysis; D050723:Fractures, Bone / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D012372:ROC Curve; D011884:Radius / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed