title: Viscoelastic dissipation in compact bone: implications for stress-induced fluid flow in bone.
abstract: Viscoelastic properties of wet and dry human compact bone were studied in torsion and in bending for both the longitudinal and transverse directions at frequencies from 5 mHz to 5 kHz in bending to more than 50 kHz in torsion. Two series of tests were done for different longitudinal and transverse specimens from a human tibia. Wet bone exhibited a larger viscoelastic damping tan delta (phase between stress and strain sinusoids) than dry bone over a broad range of frequency. All the results had in common a relative minimum in tan delta over a frequency range, 1 to 100 Hz, which is predominantly contained in normal activities. This behavior is inconsistent with an optimal "design" for bone as a shock absorber. There was no definitive damping peak in the range of frequencies explored, which could be attributed to fluid flow in the porosity of bone.
authors.affiliation: Department of Engineering Physics, University of Wisconsin-Madison 53706-1687, USA. lakes@engr.wisc.edu
authors.forename: E
authors.initials: E
authors.lastname: Garner
authors.forename: R
authors.initials: R
authors.lastname: Lakes
authors.forename: T
authors.initials: T
authors.lastname: Lee
authors.forename: C
authors.initials: C
authors.lastname: Swan
authors.forename: R
authors.initials: R
authors.lastname: Brand
mesh_terms: D000368:Aged; D001698:Biomedical Engineering / Q000295:instrumentation; D001826:Body Fluids / Q000502:physiology; D001842:Bone and Bones / Q000033:anatomy & histology / Q000502:physiology*; D004548:Elasticity; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008954:Models, Biological; D014783:Viscosity