Evaluation of Sensorimotor Ankle Impairments in Chronic Stroke

The purpose of this study is to capture sensorimotor ankle function in a chronic stroke population through validation of novel, experimental metrics and their comparison with established, clinical measures of function. Target populations will perform various single-joint ankle tasks (i.e., dorsiflexion and plantarflexion), assessing the quality of their movements during visuomotor tracking, goal-directed movements and unilateral/bilateral tests of joint position and force sense. Collecting these data will delineate which measures of ankle function are specific to chronic stroke, as well as sensitivity to the severity of stroke, assessed via the Fugl-Meyer Assessment for the Lower Extremity. In addition, the investigators will determine the relationship between deficits in proprioception and assessments which integrate multiple feedback modalities (i.e., proprioception, motor control and vision) to assess the role of peripheral sensory feedback in performing ankle movements post-stroke. The investigators will correlate measures of ankle impairment to clinical scales commonly used in physical therapy. As a first step, the investigators will directly compare these ankle measures to clinical tests of ankle sensation and motor control to demonstrate improvements in assessment sensitivity with this method. Furthermore, the investigators will correlate these ankle measures with clinical measures of lower-limb function during ambulatory and balance tasks, to better understand the contribution of ankle impairments to dynamic, multi-joint activities in chronic stroke.