title: The effect of low-mobile foot posture on multi-segment medial foot model gait kinematics.
abstract: A number of in vitro, invasive in vivo, and non-invasive marker based multi-segment foot models (MSFMs) have reported significant motion in the articulations distal to the calcaneus during gait. Few studies, however, have applied a MSFM to the investigation of the effect of foot posture on gait kinematics. Differences in stance phase kinematics between participants with low-mobile (LMF) (n=11) versus "typical" (TYPF) (n=11) foot postures were investigated using a multi-segment medial foot model. Three-dimensional position and stance phase excursions of four functional articulations (rearfoot complex [RC], calcaneonavicular complex [CNC], medial forefoot, first metatarsophalangeal complex) were quantified using an eight optical camera motion analysis system (Vicon Motus, Vicon Motions Systems, Centennial, CO) and a custom written software program (Matlab 7.0.1, The MathWorks, Natick, MA), respectively. Excursions during four subphases of stance phase (loading response, midstance, terminal stance, pre-swing) at each of the functional articulations were compared using multivariate analyses of variance (alpha<or=0.05). Results revealed significantly decreased LMF group CNC abduction excursion (p=0.047) during midstance. During pre-swing, LMF group RC inversion excursion was significantly increased (p=0.032) and eversion excursion was significantly decreased (p=0.003) compared to the TYPF group. When these differences are considered in conjunction with the kinematic patterns of other foot/leg segments and functional articulations, the changes may suggest dysfunction of normal leg-calcaneus coupling and the constrained tarsal mechanism associated with low-mobile foot postures.
authors.affiliation: Department of Human Movement Sciences, University of Wisconsin-Milwaukee, Milwaukee, WI 53201-0413, USA. cobbsc@uwm.edu
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Cobb
authors.forename: Laurie L
authors.initials: LL
authors.lastname: Tis
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Johnson
authors.forename: Yong Tai
authors.initials: YT
authors.lastname: Wang
authors.forename: Mark D
authors.initials: MD
authors.lastname: Geil
authors.forename: Frances A
authors.initials: FA
authors.lastname: McCarty
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001696:Biomechanical Phenomena; D002138:Calibration; D005260:Female; D005528:Foot / Q000502:physiology*; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted