Effect of a cognitive task during obstacle crossing in hemiparetic stroke patients

Stroke patients are at a higher risk of falling than the community-dwelling elderly, and many falls are due to contact with an obstacle. This study compared the effects of the simultaneous addition of a cognitive task during obstacle crossing between stroke patients and community-dwelling older adults (control subjects). Participants comprised 20 stroke patients who could walk with or without supervision and 20 control subjects matched for age and height with the stroke patients. Participants were asked to cross a 4-cm-high obstacle while walking at a self-selected speed. The number of failures and the spatial and temporal parameters were compared between a single-task condition (i.e., crossing task only) and a dual-task condition (i.e., verbal fluency task: listing vegetables or animals). Under the dual-task condition, six stroke patients (30%) and three community-dwelling elderly individuals (15%) failed to complete the motor task. Task failure was only due to heel-obstacle contact after toe clearance. ...