Quantitative assessment of ataxic gait using inertial sensing at different walking speeds

In this study, we employed wearable sensor technology to identify the kinematic features that are associated with the gait abnormalities seen in cerebellar ataxia. Measurements were made at self-selected slow, preferred and fast walking speeds with three sensors attached to the participant’s body. Velocity irregularity and resonant frequency characteristics were identified as key features of interest concerning truncal and lower limb movements. Using the principal component analysis, differentiating features of both trunk and lower limb movements were combined to produce an enhanced distinction between the patients and the normal subjects, in addition to obtaining a better correlation with the expert clinician’s assessments. The different speed of walking contributed to separation and correlation with medical severity rating scales such as SARA to varying degrees The results of truncal movement in the medio-lateral plane (at the slow gait speed) and antero-posterior movement (at all 3 gait speeds) provided the effective metrics in the diagnosis and severity rating of ataxic gait of CA patients. Furthermore, from the selected dominant features of the trunk and lower limb, principal component description suggested that overall clinical assessments are predominantly influenced by the lower body peripheral movements particularly at higher walking speeds.