title: Gait kinematics of subjects with ankle instability using a multisegmented foot model.
abstract: OBJECTIVE
  Many patients who sustain an acute lateral ankle sprain develop chronic ankle instability (CAI). Altered ankle kinematics have been reported to play a role in the underlying mechanisms of CAI. In previous studies, however, the foot was modeled as one rigid segment, ignoring the complexity of the ankle and foot anatomy and kinematics. The purpose of this study was to evaluate stance phase kinematics of subjects with CAI, copers, and controls during walking and running using both a rigid and a multisegmented foot model.
  
  
  METHODS
  Foot and ankle kinematics of 77 subjects (29 subjects with self-reported CAI, 24 copers, and 24 controls) were measured during barefoot walking and running using a rigid foot model and a six-segment Ghent Foot Model. Data were collected on a 20-m-long instrumented runway embedded with a force plate and a six-camera optoelectronic system. Groups were compared using statistical parametric mapping.
  
  
  RESULTS
  Both the CAI and the coper group showed similar differences during midstance and late stance compared with the control group (P < 0.05). The rigid foot segment showed a more everted position during walking compared with the control group. Based on the Ghent Foot Model, the rear foot also showed a more everted position during running. The medial forefoot showed a more inverted position for both running and walking compared with the control group.
  
  
  CONCLUSIONS
  Our study revealed significant midstance and late stance differences in rigid foot, rear foot, and medial forefoot kinematics The multisegmented foot model demonstrated intricate behavior of the foot that is not detectable with rigid foot modeling. Further research using these models is necessary to expand knowledge of foot kinematics in subjects with CAI.
authors: 1Department of Rehabilitation Sciences and Physiotherapy, Ghent University, Ghent, BELGIUM; 2Faculty of Science, School of Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, England, UNITED KINGDOM; and 3Department of Bioengineering, Shinshu University, Ueda, JAPAN.
authors: Roel
authors: R
authors: De Ridder
authors: Tine
authors: T
authors: Willems
authors: Jos
authors: J
authors: Vanrenterghem
authors: Mark
authors: M
authors: Robinson
authors: Todd
authors: T
authors: Pataky
authors: Philip
authors: P
authors: Roosen
mesh_terms: D000293:Adolescent; D000328:Adult; D000843:Ankle Joint / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D002908:Chronic Disease; D005260:Female; D005528:Foot / Q000503:physiopathology; D005684:Gait / Q000502:physiology*; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology*; D008297:Male; D008954:Models, Biological; D012420:Running / Q000502:physiology; D014741:Video Recording; D016138:Walking / Q000502:physiology; D055815:Young Adult