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. Objectives. 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.