title: Viscoelastic and failure properties of spine ligament collagen fascicles.
abstract: The microstructural volume fractions, orientations, and interactions among components vary widely for different ligament types. If these variations are understood, however, it is conceivable to develop a general ligament model that is based on microstructural properties. This paper presents a part of a much larger effort needed to develop such a model. Viscoelastic and failure properties of porcine posterior longitudinal ligament (PLL) collagen fascicles were determined. A series of subfailure and failure tests were performed at fast and slow strain rates on isolated collagen fascicles from porcine lumbar spine PLLs. A finite strain quasi-linear viscoelastic model was used to fit the fascicle experimental data. There was a significant strain rate effect in fascicle failure strain (P < 0.05), but not in failure force or failure stress. The corresponding average fast-rate and slow-rate failure strains were 0.098 ± 0.062 and 0.209 ± 0.081. The average failure force for combined fast and slow rates was 2.25 ± 1.17 N. The viscoelastic and failure properties in this paper were used to develop a microstructural ligament failure model that will be published in a subsequent paper.
authors.affiliation: Exponent Failure Analysis Associates, Biomechanics Practice, 3401 Market Street, Suite 300, Philadelphia, PA 19104, USA. slucas@exponent.com
authors.forename: Scott R
authors.initials: SR
authors.lastname: Lucas
authors.forename: Cameron R
authors.initials: CR
authors.lastname: Bass
authors.forename: Jeff R
authors.initials: JR
authors.lastname: Crandall
authors.forename: Richard W
authors.initials: RW
authors.lastname: Kent
authors.forename: Francis H
authors.initials: FH
authors.lastname: Shen
authors.forename: Robert S
authors.initials: RS
authors.lastname: Salzar
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D003094:Collagen / Q000737:chemistry*; D003198:Computer Simulation; D004548:Elasticity; D004867:Equipment Design; D020342:Finite Element Analysis; D008022:Ligaments / Q000473:pathology / Q000503:physiopathology; D008023:Ligaments, Articular / Q000503:physiopathology; D017846:Longitudinal Ligaments / Q000293:injuries / Q000503:physiopathology*; D015233:Models, Statistical; D015203:Reproducibility of Results; D013131:Spine / Q000503:physiopathology*; D013314:Stress, Mechanical; D013552:Swine; D013718:Tensile Strength; D013997:Time Factors; D014783:Viscosity
chemical_list: D003094:Collagen