title: Dual-task effect on gait balance control in adolescents with concussion.
abstract: OBJECTIVE
  To prospectively and longitudinally examine how concussion affects gait balance control in adolescents during single- and dual-task walking.
  
  
  METHODS
  Cohort, prospective, repeated-measures design.
  
  
  METHODS
  Motion analysis laboratory.
  
  
  METHODS
  Adolescents (N=20) identified as suffering a concussion were matched with healthy control subjects (N=20) and tested 5 times across a 2-month period after injury.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  Gait temporal-distance parameters included average walking speed, step length, and step width; whole body center of mass (COM) parameters included medial/lateral displacement and peak COM medial/lateral and anterior velocities; dual-task cost, which was defined as percent change from single- to dual-task conditions; and Stroop test accuracy.
  
  
  RESULTS
  No between-group differences were observed for step length and step width. The dual-task cost for average walking speed for subjects with concussion was greater than control subjects across the 2-month testing period (main effect of group P=.019), as was the dual-task costs for peak anterior COM velocity (main effect of group P=.017) and total COM medial/lateral displacement (main effect of group P=.013). The total COM medial/lateral displacement (group × task interaction P=.006) and peak COM medial/lateral velocity (main effect of group P=.027; main effect of task P=.01) were significantly greater in subjects with concussion compared with control subjects during dual-task walking. Subjects with concussion were significantly less accurate than controls on the Stroop test (main effect of group P=.004).
  
  
  CONCLUSIONS
  The findings suggest that concussion affects the ability of adolescents to control body posture during gait up to 2 months after injury. Furthermore, dual-task paradigms may provide additional useful information in the clinical assessment and recovery of concussion.
authors: Department of Human Physiology, University of Oregon, Eugene, OR, USA.
authors: David R
authors: DR
authors: Howell
authors: Louis R
authors: LR
authors: Osternig
authors: Li-Shan
authors: LS
authors: Chou
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001288:Attention / Q000502:physiology*; D001924:Brain Concussion / Q000503:physiopathology* / Q000523:psychology*; D016022:Case-Control Studies; D003071:Cognition / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D008297:Male; D004856:Postural Balance / Q000502:physiology*; D057190:Stroop Test; D013647:Task Performance and Analysis; D013997:Time Factors
keywords: Attention; Brain concussion; Brain injuries; COM; Gait; Postural balance; Rehabilitation; center of mass