Effect of Tendon Vibration on Hemiparetic Arm Stability in Unstable Workspaces. PLoS One 2015;10(12):e0144377
Date
12/04/2015Pubmed ID
26633892Pubmed Central ID
PMC4669093DOI
10.1371/journal.pone.0144377Scopus ID
2-s2.0-84956541944 (requires institutional sign-in at Scopus site) 13 CitationsAbstract
Sensory stimulation of wrist musculature can enhance stability in the proximal arm and may be a useful therapy aimed at improving arm control post-stroke. Specifically, our prior research indicates tendon vibration can enhance stability during point-to-point arm movements and in tracking tasks. The goal of the present study was to investigate the influence of forearm tendon vibration on endpoint stability, measured at the hand, immediately following forward arm movements in an unstable environment. Both proximal and distal workspaces were tested. Ten hemiparetic stroke subjects and 5 healthy controls made forward arm movements while grasping the handle of a two-joint robotic arm. At the end of each movement, the robot applied destabilizing forces. During some trials, 70 Hz vibration was applied to the forearm flexor muscle tendons. 70 Hz was used as the stimulus frequency as it lies within the range of optimal frequencies that activate the muscle spindles at the highest response rate. Endpoint position, velocity, muscle activity and grip force data were compared before, during and after vibration. Stability at the endpoint was quantified as the magnitude of oscillation about the target position, calculated from the power of the tangential velocity data. Prior to vibration, subjects produced unstable, oscillating hand movements about the target location due to the applied force field. Stability increased during vibration, as evidenced by decreased oscillation in hand tangential velocity.
Author List
Conrad MO, Gadhoke B, Scheidt RA, Schmit BDAuthors
Robert Scheidt BS,MS,PhD Associate Professor in the Biomedical Engineering department at Marquette UniversityBrian Schmit PhD Professor in the Biomedical Engineering department at Marquette University
MESH terms used to index this publication - Major topics in bold
AdultFemale
Forearm
Hand Strength
Humans
Male
Middle Aged
Movement
Muscle, Skeletal
Paresis
Proprioception
Stroke
Tendons
Vibration