Background: Mobility impairments in multiple sclerosis (MS) significantly affect quality of life. This study evaluated the clinical utility and sensitivity of the Backward Timed 25-Foot Walk Test (B-T25FW) and its associations with key clinical measures in MS.

Methods: A cross-sectional study was conducted with 129 ambulatory patients with MS from two centers. Disability (Expanded Disability Status Scale, EDSS), cognition (Symbol Digit Modalities Test, SDMT), manual dexterity (Nine-Hole Peg Test, 9HPT), fatigue, and forward and backward walking were assessed. Correlation and receiver operating characteristic (ROC) analyses were performed.

Results: The participants included in the study were 76% female, with a mean age of 38 years, and the majority were diagnosed with relapsing-remitting MS (86.8%). Backward and forward walking times significantly correlated with key clinical measures, including the EDSS, SDMT, and 9HPT. Backward walking times showed moderate correlations with EDSS (r = 0.469) and weaker but significant correlations with 9HPT (r = 0.452) and disease duration (r = 0.245). Both walking tests were negatively correlated with SDMT scores. For prognostic purposes, forward walking exhibited slightly higher predictive power compared to backward walking.

Conclusions: The B-T25FW is a clinically relevant, practical, and sensitive tool for assessing mobility impairments in individuals with MS. Its integration into clinical practice could complement forward walking assessments, enhancing disease monitoring and guiding interventions. Future research should validate its longitudinal utility.