title: Altered ankle kinematics and shank-rear-foot coupling in those with chronic ankle instability.
abstract: BACKGROUND
  Kinematic patterns during gait have not been extensively studied in relation to chronic ankle instability (CAI).
  
  
  OBJECTIVE
  To determine whether individuals with CAI demonstrate altered ankle kinematics and shank-rear-foot coupling compared with controls during walking and jogging.
  
  
  METHODS
  Case control.
  
  
  METHODS
  Motion-analysis laboratory.
  
  
  METHODS
  7 participants (3 men, 4 women) suffering from CAI (age 24.6 +/- 4.2 y, height 172.6 +/- 9.4 cm, mass 70.9 +/- 8.1 kg) and 7 (3 men, 4 women) healthy, matched controls (age 24.7 +/- 4.5 y, height 168.2 +/- 5.9 cm, mass 66.5 +/- 9.8 kg).
  
  
  METHODS
  Subjects walked and jogged on a treadmill while 3-dimensional kinematics of the lower extremities were captured.
  
  
  METHODS
  The positions of rear-foot inversion-eversion and shank rotation were calculated throughout the gait cycle. Continuous relative-phase angles between these segments were calculated to assess coupling.
  
  
  RESULTS
  The CAI group demonstrated more rear-foot inversion and shank external rotation during walking and jogging. There were differences between groups in shank-rear-foot coupling during terminal swing at both speeds.
  
  
  CONCLUSIONS
  Altered ankle kinematics and joint coupling during the terminal-swing phase of gait may predispose a population with CAI to ankle-inversion injuries. Less coordinated movement during gait may be an indication of altered neuromuscular recruitment of the musculature surrounding the ankle as the foot is being positioned for initial contact.
authors.affiliation: Dept of Human Services, University of Virginia, Charlottesville, VA, USA.
authors.forename: Lindsay K
authors.initials: LK
authors.lastname: Drewes
authors.forename: Patrick O
authors.initials: PO
authors.lastname: McKeon
authors.forename: Gabriele
authors.initials: G
authors.lastname: Paolini
authors.forename: Patrick
authors.initials: P
authors.lastname: Riley
authors.forename: D Casey
authors.initials: DC
authors.lastname: Kerrigan
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Ingersoll
authors.forename: Jay
authors.initials: J
authors.lastname: Hertel
mesh_terms: D000328:Adult; D000842:Ankle / Q000502:physiology; D000843:Ankle Joint / Q000503:physiopathology*; D000886:Anthropometry; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D004185:Disability Evaluation; D005260:Female; D005684:Gait / Q000502:physiology*; D006305:Health Status Indicators; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology*; D008297:Male; D012420:Running / Q000502:physiology*; D013180:Sprains and Strains; D016138:Walking / Q000502:physiology*