1Razieh Mofateh, 2Reza Salehi, 3Hossein Negahban, 1Mohammad Mehravar, 4Shirin Tajali, 1Saeideh Monjezi

1Musculoskeletal Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation sciences, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran; 2Rehabilitation Research Center, and School of Rehabilitation Sciences, Department of Rehabilitation Management, Iran University of Medical Sciences, Tehran, Iran; 3Mashhad University of Medical Sciences, Mashhad, Iran; 4Department of Physical Therapy, University of Toronto, Toronto, Ontario, Canada., Toronto, Canada


Gait disturbance is one of the most common and disabling signs in patients with multiple sclerosis (MS). Coordinative ability between segments of lower extremities, as a higher order property of the human movement system, is affected by MS disease. Since intersegmental coordination could be affected by cognitive loading, this study was aimed to investigate the interaction between cognition and lower extremities inter-segmental coordination during walking in patients with MS.

Material(s) and Method(s):

The investigation included 25 patients with MS and 25 matched healthy controls. Participants walked at their preferred speed on a motorized treadmill under two walking conditions in a randomized order: walking only, walking while performing a concurrent cognitive task (counting backward aloud by 3s). The mean absolute relative phase (MARP) and deviation phase (DP) were used to calculate the phase dynamic and variability of inter-segmental coordination over the stance and swing phases of gait for each condition.


The statistical analyses showed that the interaction of task and group was only significant for MARP value of the shank-thigh in stance phase (p=0.02). Group had a significant main effect on DP of shank-thigh and foot-shank in stance and swing phases and MARP of shank-thigh in stance phase and foot-shank in stance and swing phases (p<0.01). In addition, the main effect of task was significant on MARP and DP of shank-thigh and foot-shank in stance and swing phases (p<0.01).


Our results suggest that simultaneous performance of cognitive task and walking could lead to higher changes in the inter-segmental coordination compared to single walking. Thus, therapeutic exercise aimed to improve lower extremities inter-segmental coordination should be considered in the rehabilitative interventions of MS patients.