title: The choice of a constitutive formulation for modeling limb flexion-induced deformations and stresses in the human femoropopliteal arteries of different ages.
abstract: Open and endovascular treatments for peripheral arterial disease are notorious for high failure rates. Severe mechanical deformations experienced by the femoropopliteal artery (FPA) during limb flexion and interactions between the artery and repair materials play important roles and may contribute to poor clinical outcomes. Computational modeling can help optimize FPA repair, but these simulations heavily depend on the choice of constitutive model describing the arterial behavior. In this study finite element model of the FPA in the standing (straight) and gardening (acutely bent) postures was built using computed tomography data, longitudinal pre-stretch and biaxially determined mechanical properties. Springs and dashpots were used to represent surrounding tissue forces associated with limb flexion-induced deformations. These forces were then used with age-specific longitudinal pre-stretch and mechanical properties to obtain deformed FPA configurations for seven age groups. Four commonly used invariant-based constitutive models were compared to determine the accuracy of capturing deformations and stresses in each age group. The four-fiber FPA model most accurately portrayed arterial behavior in all ages, but in subjects younger than 40 years, the performance of all constitutive formulations was similar. In older subjects, Demiray (Delfino) and classic two-fiber Holzapfel-Gasser-Ogden formulations were better than the Neo-Hookean model for predicting deformations due to limb flexion, but both significantly overestimated principal stresses compared to the FPA or Neo-Hookean models.
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA. Anastasia.Desyatova@unmc.edu.
authors.forename: Anastasia
authors.identifier: http://orcid.org/0000-0001-5016-6162
authors.initials: A
authors.lastname: Desyatova
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: MacTaggart
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors.forename: William
authors.initials: W
authors.lastname: Poulson
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Deegan
authors.affiliation: Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE, USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Lomneth
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA.
authors.forename: Anjali
authors.initials: A
authors.lastname: Sandip
authors.affiliation: Department of Surgery, 987690 Nebraska Medical Center, University of Nebraska Medical Center, Omaha, NE, 68198-7690, USA. Alexey.Kamenskiy@unmc.edu.
authors.forename: Alexey
authors.initials: A
authors.lastname: Kamenskiy
mesh_terms: D000367:Age Factors; D001158:Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D003198:Computer Simulation; D005269:Femur / Q000098:blood supply* / Q000000981:diagnostic imaging; D006801:Humans; D007596:Joints / Q000098:blood supply / Q000000981:diagnostic imaging; D008954:Models, Biological; D013314:Stress, Mechanical; D014057:Tomography, X-Ray Computed
keywords: Constitutive model; Femoropopliteal artery; Finite element modeling; Limb flexion