1Musculoskeletal Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation sciences, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
Deficit in dual- task performance have been commonly reported in patients with MS, potentially leading to increase the likelihood of falls occurring in these patients. The purpose of the current study was to compare the effects of cognitive or motor tasks on gait performance between healthy controls and multiple sclerosis (MS) patients with and without fall history.
Material(s) and Method(s):
The current study design was cross-sectional. The investigation included MS patients with fall history (n=25) and without fall history (n=25) and matched healthy controls (n=25). Participants walked at their preferred speed on a motorized treadmill under three walking conditions in a randomized order: walking only, walking while performing a concurrent cognitive task (counting backward aloud by 3s), and walking while performing a concurrent motor task (carrying a tray with glasses). Gait performance was assessed by cadence, stride length, step width, and swing time. In addition, gait variability was calculated for stride length, stride time, and step width parameters using coefficient of variation. We used a two-way repeated measure analysis of variance for statistical analysis.
The findings showed that in patients with MS, regardless of fall history, spatiotemporal gait parameters were different compared to healthy controls. In contrast to average gait parameters, variability in stride length and stride time could discriminate between MS fallers and non-fallers. Simultaneous performance of cognitive task and walking resulted in higher dual-task costs (DTC) in gait performance compared to the motor dual-task. However, the pattern of change was not different among the three groups. All participants responded to the cognitive task challenges by increasing stride length and decreasing cadence and stride length variability while maintaining cognitive task performance.
The findings may reflect successful adaptation of locomotor system to preserve cognitive task performance under cognitive dual-task condition. Future studies should examine more complex concurrent cognitive and motor tasks to better understand the dual-task-related gait changes and their contribution to falls in patients with MS.