title: Digital tomosynthesis (DTS) for quantitative assessment of trabecular microstructure in human vertebral bone.
abstract: Digital tomosynthesis (DTS) provides slice images of an object using conventional radiographic methods with high in-plane resolution. The objective of this study was to explore the potential of DTS for describing microstructural, stiffness and stress distribution properties of vertebral cancellous bone. Forty vertebrae (T6, T8, T11, and L3) from 10 cadavers (63-90 years) were scanned using microCT and DTS. Anisotropy (μCT.DA), and the specimen-average and standard deviation of trabecular bone volume fraction (BV/TV), thickness (Tb.Th), number (Tb.N) and separation (Tb.Sp) were obtained using stereology. Apparent modulus (EFEM), and the magnitude (VMExp/σapp) and variability (VMCV) of trabecular stresses were calculated using microCT-based finite element modeling. Mean intercept length, line fraction deviation and fractal parameters were obtained from coronal DTS slices, then correlated with stereological and finite element parameters using linear regression models. Twenty-one DTS parameters (out of 27) correlated to BV/TV, Tb.Th, Tb.N, Tb.Sp and/or μCT.DA (p<0.0001-p<0.05). DTS parameters increased the explained variability in EFEM and VMCV (by 9-11% and 13-19%, respectively; p<0.0001-p<0.04) over that explained by BV/TV. In conclusion, DTS has potential for quantitative assessment of cancellous bone and may be used as a modality complementary to those measuring bone mass for assessing spinal fracture risk.
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States. Electronic address: woongkim79@gmail.com.
authors.forename: Woong
authors.initials: W
authors.lastname: Kim
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Oravec
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: Srikant
authors.initials: S
authors.lastname: Nekkanty
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: Janardhan
authors.initials: J
authors.lastname: Yerramshetty
authors.affiliation: Department of Biomedical Engineering, The University of Iowa, Iowa City, IA, United States.
authors.forename: Edward A
authors.initials: EA
authors.lastname: Sander
authors.affiliation: Department of Public Health Science, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: George W
authors.initials: GW
authors.lastname: Divine
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Flynn
authors.affiliation: Bone and Joint Center, Henry Ford Hospital, Detroit, MI, United States.
authors.forename: Yener N
authors.initials: YN
authors.lastname: Yeni
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016880:Anisotropy; D004548:Elasticity; D005260:Female; D020342:Finite Element Analysis; D017709:Fractals; D006801:Humans; D016014:Linear Models; D008297:Male; D009929:Organ Size; D011859:Radiography; D013131:Spine / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology; D013314:Stress, Mechanical; D014054:Tomography / Q000379:methods*
keywords: Bone biomechanics; Digital tomosynthesis; Finite element analysis; Fractal dimension; Heterogeneity; Lacunarity; Line fraction deviation; Microcomputed tomography; Spine; Stress distribution