title: Does a specific MR imaging protocol with a supine-lying subject replicate tarsal kinematics seen during upright standing?
abstract: Magnetic resonance (MR) imaging is becoming increasingly important in the study of foot biomechanics. Specific devices have been constructed to load and position the foot while the subject is lying supine in the scanner. The present study examines the efficacy of such a newly developed device in replicating tarsal kinematics seen during the more commonly studied standing loading conditions. The results showed that although knee flexion and the externally applied load were carefully controlled, subtalar and talo-navicular joint rotations while lying during MR imaging and when standing (measured opto-electrically with markers attached to intracortical pins) did not match, nor were they systematically shifted. Thus, the proposed MR protocol cannot replicate tarsal kinematics seen during upright standing. It is concluded that specific foot loading conditions have to be considered when tarsal kinematics are evaluated. Improved replication of tarsal kinematics in different postures should comprehensively consider muscle activity, a fixed hip position, and a well-defined point of load application.
authors: Institute for Biomechanics, ETH Zurich, Zurich, Switzerland. pwolf@ethz.ch
authors: Peter
authors: P
authors: Wolf
authors: Alex
authors: A
authors: Stacoff
authors: Anmin
authors: A
authors: Liu
authors: Anton
authors: A
authors: Arndt
authors: Chris
authors: C
authors: Nester
authors: Arne
authors: A
authors: Lundberg
authors: Edgar
authors: E
authors: Stuessi
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena / Q000379:methods; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016683:Supine Position / Q000502:physiology; D013639:Tarsal Bones / Q000033:anatomy & histology* / Q000502:physiology*; D013640:Tarsal Joints / Q000033:anatomy & histology* / Q000502:physiology*