Effects of dual- and complex-task on walking ability of ambulatory individuals with spinal cord injury.

BACKGROUND: Attempting to perform dual- and complex-tasks obviously reduces the walking ability of individuals with impaired cognitive functions. However, there is no clear evidence describing the effects of dual- and complex-tasks on the walking ability of ambulatory individuals with a spinal cord injury (SCI) who have intact cognitive functions, but suffer from various degrees of sensorimotor deterioration.

AIM: To primarily investigate the effects of dual- and complex-task on the walking ability of ambulatory subjects with SCI as compared to healthy individuals. In addition, the study secondarily compared the effects in subgroups of subjects with SCI, including different age groups, lesion severity and level of ability.

DESIGN: Cross-sectional design.

SETTING: A major tertiary referral and community hospitals in Thailand.

POPULATION: Thirty-seven ambulatory individuals with SCI and 13 healthy subjects.

METHODS: All subjects were evaluated for outcomes while they walked under four conditions, including single-task overground walking (ST-OG), dual-task overground walking (DT-OG) using a color word Stroop task, single-task obstacle crossing (ST-OC) and dual-task obstacle crossing (DT-OC). The outcomes were compared among the conditions and between the groups of subjects in terms of walking time, obstacle crossing ability and percent of Stroop task errors.

RESULTS: With the increasing complexity of the tasks, both SCI and healthy subjects walked significantly slower (P<0.001 for those with SCI and P<0.05 for healthy subjects), but not when compared between the ST-OC and DT-OG conditions (P>0.05). Subjects also showed a greater percentage of cognitive task errors when they encountered a dual- and complex-task, particularly those with SCI who were over 50 years old, had mild lesion severity or walked with a walking device (P<0.001).

CONCLUSIONS: The incorporation of dual- and complex-task challenged cognitive-motor interference of ambulatory individuals with SCI.

CLINICAL REHABILITATION IMPACT: The application of such tasks may benefit rehabilitation outcomes in a real-world situation for patients, especially for those who are older than 50, have mild lesion severity or use a walking device.