title: Are tensile and compressive Young's moduli of compact bone different?
abstract: This study examines the question of whether the stiffness (Young's modulus) of secondary osteonal cortical bone is different in compression and tension. Electronic speckle pattern interferometry (ESPI) is used to measure concurrently the compressive and tensile strains in cortical bone beams tested in bending. ESPI is a non-contact method of measuring surface deformations over the entire region of interest of a specimen, tested wet. The measured strain distributions across the beam, and the determination of the location of the neutral axis, demonstrate in a statistically-robust way that the tensile Young's modulus is slightly (6%), but significantly greater than that of the compressive Young's modulus. It is also shown that within a relatively small bone specimen there are considerable variations in the modulus, presumably caused by structural inhomogeneities.
authors.affiliation: Department of Structural Biology, Weizmann Institute of Science, Israel.
authors.forename: Meir M
authors.initials: MM
authors.lastname: Barak
authors.forename: John D
authors.initials: JD
authors.lastname: Currey
authors.forename: Steve
authors.initials: S
authors.lastname: Weiner
authors.forename: Ron
authors.initials: R
authors.lastname: Shahar
mesh_terms: D000818:Animals; D001842:Bone and Bones / Q000502:physiology*; D019245:Compressive Strength; D055119:Elastic Modulus; D005260:Female; D006736:Horses; D006801:Humans; D007101:Immersion; D007368:Interferometry; D008297:Male; D013500:Surface Tension; D013718:Tensile Strength; D013997:Time Factors; D014867:Water; D016474:Weight-Bearing
chemical_list: D014867:Water