Relationship Between Single- and Dual-Task Obstacle Crossing Performance and Fatigue and Disability in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system that frequently causes gait impairment, fatigue, cognitive dysfunction, and reduced functional mobility. Since daily activities often require simultaneous motor and cognitive performance, assessment under dual-task conditions provides clinically meaningful information beyond conventional gait evaluation.

Obstacle crossing represents a more demanding walking task than level walking and may better reflect mobility challenges encountered in everyday life. Although dual-task walking has been investigated in individuals with MS, studies examining obstacle crossing performance under both single-task and dual-task conditions and its relationship with fatigue and disability remain limited.

This cross-sectional observational study will include men and women aged 18 to 65 years with Relapsing-Remitting Multiple Sclerosis who are followed at the Neurology Outpatient Clinic of Kocaeli City Hospital. Participants will complete walking assessments under four conditions: single-task walking, dual-task walking, single-task obstacle crossing, and dual-task obstacle crossing. The dual-task condition will require participants to perform serial-3 subtraction while walking.

Clinical assessments including fatigue, walking limitation, cognition, health-related quality of life, and fear of movement will also be collected. The study aims to determine the association between obstacle crossing performance and fatigue and disability levels in individuals with RRMS.

Inclusion criteria

• Age between 18 and 65 years.
• Diagnosis of Multiple Sclerosis according to the 2017 McDonald criteria.
• Diagnosis of Relapsing-Remitting Multiple Sclerosis.
• Expanded Disability Status Scale (EDSS) score between 0 and 6.
• Clinically stable disease during the previous 6 months.
• Montreal Cognitive Assessment (MoCA) score of 26 or higher.
• Able to speak and understand Turkish.
• Able to provide written informed consent.

Exclusion criteria

• Multiple sclerosis relapse within the previous month.
• Physician-diagnosed psychiatric disorder.
• Neurological, orthopedic, cardiac, or pulmonary disease other than Multiple Sclerosis that could interfere with study assessments.
• Montreal Cognitive Assessment (MoCA) score below 26.