ASYMMETRY IN WALKING PERFORMANCE AND POSTURAL SWAY IN PATIENTS WITH CHRONIC UNILATERAL CEREBRAL INFARCTION

The asymmetrical nature of hemiparetic gait is well known; however, th e role of walking asymmetry for speed performance is unclear. The purp ose of the present study was to determine whether the range of walking speeds in chronic hemiparetic patients is associated with their gait asymmetry and postural sway. Twenty ambulatory patients with chronic u nilateral supratentorial infarction were studied. Foot-ground contact patterns during swing and stance phases at various self-selected walki ng speeds were analyzed. The magnitude and direction of asymmetry in d urations of stride phases were evaluated and compared with healthy sub jects. Posturographic studies were performed to estimate the postural sway during quiet standing. Hemiparetic patients walked slower, more a symmetrically, and swayed more laterally favoring their nonaffected le g than did healthy persons. Although there was variability in duration s of stride phases when comparing the two sides, a prolonged swing on the affected side and a prolonged stance on the nonaffected side were observed in all patients. The magnitude of asymmetry in stride phases varied among the patients; however, it was significantly higher than i n controls (p<0.03). Increased mean lateral sway during quiet standing was indicative of restricted velocity performance during walking. Pat ients with higher swing asymmetry achieved their maximum speed perform ance at lower velocity levels. However, the ability of patients to amb ulate with a number of self-selected speeds was not associated with th e magnitude of their overall gait asymmetry. Patients with right hemis phere lesions appeared to have less ambulatory ability than patients w ith left hemisphere lesions.