Clin Neurophysiol 2019 Jun 13;130(6):1008-1016. Epub 2019 Apr 13.
Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, USA.
Objectives: Goal-directed movements are essential for voluntary motor control. The inability to execute precise goal-directed movements after stroke can impair the ability to perform voluntary functions, learn new skills, and hinder rehabilitation. However, little is known about how the accuracy of single-joint, goal-directed ankle movements relates to multi-joint, lower limb function in stroke. Here, we determined the impact of stroke on the accuracy of goal-directed ankle movements and its relation to over-ground walking.
Methods: Stroke (N = 28) and control (N = 28) participants performed (1) goal-directed ankle dorsiflexion movements to accurately match 9 degrees in 180 ms and (2) over-ground walking. During goal-directed ankle movements, we measured the endpoint error, position error, time error and the activation of the agonist and antagonist muscles. During over-ground walking, we measured the walking speed, paretic stride length, and cadence.
Results: The stroke group demonstrated increased endpoint error than the controls. Increased endpoint error was associated with increased co-activation between agonist-antagonist muscles. Endpoint error was a significant predictor of walking speed and paretic stride length in stroke.
Conclusions: Impaired accuracy of goal-directed, ankle movements is correlated to over-ground walking in stroke.
Significance: Quantifying accuracy of goal-directed ankle movements may provide insights into walking function post-stroke.