title: Gait stability following concussion.
abstract: BACKGROUND
  The need to identify functional impairment following a brain injury is critical to prevent reinjury during the period of recovery. However, little is known about the effect of concussion on dynamic motor function.
  
  
  OBJECTIVE
  The purpose of this study was to examine the effect of concussion on a dynamic motor task under conditions of divided and undivided attention over the course of 28 d.
  
  
  METHODS
  Fifteen subjects with concussions (CONC) and 15 uninjured controls (NORM) were observed while walking with undivided attention and while concurrently completing simple mental tasks. The CONC were assessed within 48 h of injury and again at 5, 14, and 28 d postinjury. The NORM were evaluated at the same time intervals. Whole-body motion data were collected to examine displacement and velocity of the center of mass (COM) and the maximum separation between the COM and center of pressure (COP). Three-way repeated-measures mixed-design ANOVA and Tukey post hoc tests were completed to determine differences between group, task, and testing day (P<0.05).
  
  
  RESULTS
  Several aspects of gait stability were compromised in the CONC group for up to 4 wk after injury. CONC were found to walk significantly slower during dual tasks on all testing days when compared with the uninjured controls. The injured subjects were also found to have greater sway and sway velocity than controls when attention was divided for up to 28 d postinjury.
  
  
  CONCLUSIONS
  The findings of this study suggest that concussion may have long-term observable and measurable effects on the control of gait stability.
authors.affiliation: Motion Analysis Laboratory, Department of Human Physiology, University of Oregon, Eugene, OR 97403, USA.
authors.forename: Tonya M
authors.initials: TM
authors.lastname: Parker
authors.forename: Louis R
authors.initials: LR
authors.lastname: Osternig
authors.forename: Paul
authors.initials: P
authors.lastname: VAN Donkelaar
authors.forename: Li-Shan
authors.initials: LS
authors.lastname: Chou
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology; D001924:Brain Concussion / Q000150:complications / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D005684:Gait / Q000502:physiology*; D020233:Gait Disorders, Neurologic / Q000209:etiology; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology; D009048:Motor Skills / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology; D013997:Time Factors; D016138:Walking / Q000502:physiology