title: Changes in gait symmetry and velocity after stroke: a cross-sectional study from weeks to years after stroke.
abstract: BACKGROUND
  There is little information about the quality of gait in the years following stroke. Long-term changes in mobility, using global indices of function, suggest a decline well after initial rehabilitation. However, global indices of mobility do not reveal more specific changes in walking competency or underlying gait-specific impairment.
  
  
  OBJECTIVE
  The authors used a cross-sectional design with gait-specific measures (velocity and symmetry) to investigate whether deterioration in gait occurs over the long term poststroke.
  
  
  METHODS
  Data were abstracted from a standardized database containing clinical assessments and spatiotemporal gait analyses for 171 individuals with stroke. Velocity and 3 expressions of symmetry ratios (swing time, stance time, and step length) were calculated for each individual; they were then assigned to 1 of the 5 following groups: 0 to 3, 3 to 12, 12 to 24, 24 to 48, and >48 months poststroke.
  
  
  RESULTS
  Swing time, stance time, and step length symmetry demonstrated a systematic linear trend toward greater asymmetry in groups in the later stages poststroke, whereas velocity, neurological deficit, and lower-extremity (LE) motor impairment did not.
  
  
  CONCLUSIONS
  The quality of gait, as measured by spatial and temporal symmetry, appears to worsen in later years. These results suggest a dissociation between quantitative measures of gait, such as velocity versus symmetry, and that these parameters may measure independent features. A longitudinal study is needed to confirm the presence and to interpret the clinical meaning of a long-term decline in specific parameters of poststroke gait.
authors.affiliation: University of Toronto, Toronto, ON, Canada.
authors.forename: Kara K
authors.initials: KK
authors.lastname: Patterson
authors.forename: William H
authors.initials: WH
authors.lastname: Gage
authors.forename: Dina
authors.initials: D
authors.lastname: Brooks
authors.forename: Sandra E
authors.initials: SE
authors.lastname: Black
authors.forename: William E
authors.initials: WE
authors.lastname: McIlroy
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D004185:Disability Evaluation; D005260:Female; D005684:Gait / Q000502:physiology*; D020233:Gait Disorders, Neurologic / Q000150:complications* / Q000503:physiopathology* / Q000534:rehabilitation; D006801:Humans; D007866:Leg / Q000294:innervation / Q000503:physiopathology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D051346:Mobility Limitation; D020521:Stroke / Q000150:complications* / Q000503:physiopathology*; D000071939:Stroke Rehabilitation; D013997:Time Factors; D016138:Walking / Q000502:physiology