Multiple Sclerosis (MS) leads to disability including deterioration of balance and gait (Kalron, 2016) that often prevent people with MS (PwMS) from performing activities of daily living (Callesen et al., 2019). Balance control relies on the integration of inputs from the somatosensory, vestibular, and visual systems, which together with the muscular system ensure sufficient upright posture and stability during walking.

Walking capacity is closely associated with posture balance and increased disability is associated with decreased walking speed and altered gait patterns (Kalron, 2016; Pommerich et al., 2022). Recently, Callesen et al. (2019) demonstrated that static and dynamic balance along with maximal muscle strength of the lower limbs were all significantly associated with walking speed and distance/endurance, whereas only balance was related to more complex walking tasks (e.g. changing direction).

It remains unknown how the different sensory systems are associated with the level of complexity of walking capacity tasks and with self-reported walking ability. Knowledge on these associations could help guide clinicians in interpreting results from different walking outcomes aimed at providing the optimal gait interventions.

This study aims at evaluating the associations between somatosensory, vestibular, and visual systems, assessed through the Sensory Organization Test (SOT) (EquiTest, Neurocom, Clackamas, OR, USA) (Brichetto et al., 2015), and measures of walking capacity at low (Timed 25-Foot Walk, T25FW), medium (Timed Up-and-Go Test, TUG), and high (Six-Spot-Step-Test, SSST) complexity level and self-reported measures of walking ability (12-Item MS Walking Scale, MSWS-12).