title: A comparison between dynamic implicit and explicit finite element simulations of the native knee joint.
abstract: The finite element (FE) method has been widely used to investigate knee biomechanics. Time integration algorithms for dynamic problems in finite element analysis can be classified as either implicit or explicit. Although previously both static/dynamic implicit and dynamic explicit method have been used, a comparative study on the outcomes of both methods is of high interest for the knee modeling community. The aim of this study is to compare static, dynamic implicit and dynamic explicit solutions in analyses of the knee joint to assess the prediction of dynamic effects, potential convergence problems, the accuracy and stability of the calculations, the difference in computational time, and the influence of mass-scaling in the explicit formulation. The heel-strike phase of fast, normal and slow gait was simulated for two different body masses in a model of the native knee. Our results indicate that ignoring the dynamic effect can alter joint motion. Explicit analyses are suitable to simulate dynamic loading of the knee joint in high-speed simulations, as this method offers a substantial reduction of the computational time with a similar prediction of cartilage stresses and meniscus strains. Although mass-scaling can provide even more gain in computational time, it is not recommended for high-speed activities, in which inertial forces play a significant role.
authors.affiliation: Orthopedic Research Lab, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands . Electronic address: Hamid.NaghibiBeidokhti@radboudumc.nl.
authors.forename: Hamid
authors.initials: H
authors.lastname: Naghibi Beidokhti
authors.affiliation: Orthopedic Research Lab, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
authors.forename: Dennis
authors.initials: D
authors.lastname: Janssen
authors.affiliation: Orthopedic Research Lab, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Khoshgoftar
authors.affiliation: Orthopedic Research Lab, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
authors.forename: Andre
authors.initials: A
authors.lastname: Sprengers
authors.affiliation: Faculty of Engineering Technology, University of Twente, 7500 AE Enschede, The Netherlands.
authors.forename: Emin Semih
authors.initials: ES
authors.lastname: Perdahcioglu
authors.affiliation: Faculty of Engineering Technology, University of Twente, 7500 AE Enschede, The Netherlands.
authors.forename: Ton
authors.initials: T
authors.lastname: Van den Boogaard
authors.affiliation: Orthopedic Research Lab, Radboud Institute for Health Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands ; Laboratory of Biomechanical Engineering, University of Twente, 7500 AE Enschede, The Netherlands.
authors.forename: Nico
authors.initials: N
authors.lastname: Verdonschot
mesh_terms: D001696:Biomechanical Phenomena; D002102:Cadaver; D005269:Femur / Q000502:physiology; D020342:Finite Element Analysis; D005684:Gait; D006801:Humans; D007700:Kinetics; D007719:Knee Joint / Q000502:physiology; D055595:Mechanical Phenomena; D013977:Tibia / Q000502:physiology
keywords: Dynamic analysis; Explicit FEM; Finite element method; Implicit FEM; Knee joint; Mass scaling