Effect of Stroke on Joint Control during Reach-to-Grasp: A Preliminary Study

Sandesh Raj, Natalia Dounskaia, William W. Clark, Amit Sethi

    Research output: Contribution to journalArticle


    We investigated changes in control of inter-segmental dynamics underlying upper extremity dyscoordination caused by stroke. Individuals with stroke and healthy individuals performed a natural reach-to-grasp movement. Kinetic analysis revealed that both groups rotated the shoulder by muscle torque and used interaction torque to rotate the elbow. However, individuals with stroke used interaction torque less than healthy individuals, actively suppressing a substantial portion of it. This resulted in inefficient use of active control and dyscoordination of the upper extremity. The degree of interaction torque suppression and inefficiency of active control at the elbow positively correlated with stroke severity. The increased interaction torque suppression can be a strategy used by individuals with stroke to compensate for deficient feedforward control of this torque.

    Original languageEnglish (US)
    JournalJournal of motor behavior
    Publication statusPublished - Jan 1 2019



    • feedforward control
    • Hemiparesis
    • inter-segmental dynamics
    • interaction torque
    • joint coordination
    • submovements

    ASJC Scopus subject areas

    • Biophysics
    • Orthopedics and Sports Medicine
    • Experimental and Cognitive Psychology
    • Cognitive Neuroscience

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