A case report on gait in spinocerebellar ataxia: evaluating the use of mixed reality from independent walking to integrated physical support.

Mixed Reality (MR) provides promising tools for gait training and rehabilitation, offering tasks tailored to improve balance, gait, and muscle strength for individuals with gait impairments. However, its effects on individuals with balance impairments such as ataxia are not fully understood, concerning the interaction with and without physical assistive devices. Understanding this interaction is important for developing therapies that are both safe and effective for individuals with mobility impairments. This paper investigates this interaction in a patient with mild spinocerebellar ataxia across four different walking tasks: (i) unassisted walk in the physical environment, (ii) unassisted walk using an MR headset, (iii) assisted walk with a smart walker (SW), and (iv) assisted walk using both the SW and the MR headset. Results indicate that without physical support, the MR environment induced a cautious gait, decreasing step length by 8.7% and velocity by 14.8% compared to walking in the physical environment. In contrast, when the SW provided stability, the same MR environment improved performance, increasing step length by 22.5% and velocity by 37.9% compared to walking with the SW alone. This contrast may be explained by the patient's qualitative feedback, which linked the cautious gait in the unassisted MR task to a fear of falling that was eliminated by the support of the SW. Combining an assistive device with an immersive task is a valuable tool for enhancing safety, however, such assistance must be carefully tailored to avoid restricting the user's natural mobility patterns.