Background: Instead of hyper-reflexia as sole paradigm, post-stroke movement disorders are currently considered the result of a complex interplay between neuronal and muscular properties, modified by level of activity. We used a closed loop system identification technique to quantify individual contributors to wrist joint stiffness during an active posture task.
Methods: Continuous random torque perturbations applied to the wrist joint by a haptic manipulator had to be resisted maximally.