title: Dependence of mechanical properties of trabecular bone on plate-rod microstructure determined by individual trabecula segmentation (ITS).
abstract: Individual trabecula segmentation (ITS) technique can decompose the trabecular bone network into individual trabecular plates and rods and is capable of quantifying the plate/rod-related microstructural characteristics of trabecular bone. This novel technique has been shown to be able to provide in-depth insights into micromechanics and failure mechanisms of human trabecular bone, as well as to distinguish the fracture status independent of area bone mineral density in clinical applications. However, the plate/rod microstructural parameters from ITS have never been correlated to experimentally determined mechanical properties of human trabecular bone. In this study, on-axis cylindrical trabecular bone samples from human proximal tibia (n=22), vertebral body (n=10), and proximal femur (n=21) were harvested, prepared, scanned using micro computed-tomography (µCT), analyzed with ITS and mechanically tested. Regression analyses showed that the plate bone volume fraction (pBV/TV) and axial bone volume fraction (aBV/TV) calculated by ITS analysis correlated the best with elastic modulus (R(2)=0.96-0.97) and yield strength (R(2)=0.95-0.96). Trabecular plate-related microstructural parameters correlated highly with elastic modulus and yield strength, while most rod-related parameters were found inversely and only moderately correlated with the mechanical properties. In addition, ITS analysis also identified that trabecular bone at human femoral neck had the highest trabecular plate-related parameters while the other sites were similar with each other in terms of plate-rod microstructure.
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA.
authors.forename: Bin
authors.initials: B
authors.lastname: Zhou
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA; McKay Orthopaedic Research Laboratory, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: X Sherry
authors.initials: XS
authors.lastname: Liu
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA.
authors.forename: Ji
authors.initials: J
authors.lastname: Wang
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA; Cartilage Bioengineering Laboratory, Department of Mechanical Engineering, University of Delaware, Newark, DE, USA.
authors.forename: X Lucas
authors.initials: XL
authors.lastname: Lu
authors.affiliation: Department of Orthopaedic Surgery, University of California, San Francisco, CA, USA; Orthopaedic Biomechanics Laboratory, Department of Mechanical Engineering, University of California, Berkeley, CA, USA.
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Fields
authors.affiliation: Bone Bioengineering Laboratory, Department of Biomedical Engineering, Columbia University, New York, NY, USA. Electronic address: ed.guo@columbia.edu.
authors.forename: X Edward
authors.initials: XE
authors.lastname: Guo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena / Q000502:physiology; D015519:Bone Density / Q000502:physiology; D019245:Compressive Strength / Q000502:physiology; D055119:Elastic Modulus / Q000502:physiology*; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000502:physiology* / Q000648:ultrastructure; D050723:Fractures, Bone / Q000000981:diagnostic imaging; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000503:physiopathology; D013131:Spine / Q000000981:diagnostic imaging / Q000502:physiology* / Q000648:ultrastructure; D013977:Tibia / Q000000981:diagnostic imaging / Q000502:physiology* / Q000648:ultrastructure; D055114:X-Ray Microtomography / Q000379:methods
keywords: Individual trabecula segmentation; Mechancial properties; Microstructure; Trabecular bone