Short-Term Ankle Motor Performance With Ankle Robotics Training in Chronic Hemiparetic Stroke
By Roy, Anindo; Forrester, Larry W.; Macko, Richard F.; Journal of Rehabilitation Research and Development, Vol. 48, No. 4, pp. 417-430Publication Date: 2011
Study investigated the short term effects of a single session of impedance-controlled ankle robot, or “anklebot”, training on paretic ankle motor control in chronic stroke. The anklebot is defined as a three degrees of freedom wearable exoskeleton that allows normal ankle range of motion in all three DOF of the foot relative to the shank but actuates only dorsiflexion/plantar flexion and inversion/eversion with up to 17 newton meters of ankle torque. Its backdriveability allows an individual with diminished limb function to easily move the robot endpoint and allows the robot to interact stably and safely with the user. Participants were 7 patients with chronic hemiparetic stroke and a mean age of 63 years, of whom 2 were male, and an equal number of age- and sex-matched nondisabled controls. Training consisted of participants in each group playing a target based video game with the anklebot for an hour, for a total of 560 movement repetitions in dorsiflexion/plantar flexion ranges followed by retest 48 hours later. Task difficulty was adjusted to ankle range of motion, with robotic assistance decreased incrementally across training. Assessments included robotic measures of ankle motor control on unassisted trials before and after training and at 48 hours after training. Following training, participants with stroke improved paretic ankle motor control across a single training session as indexed by increased targeting accuracy, higher angular speeds, and smoother movements. In contrast, nondisabled participants did not make statistically significant gains in any metric after training except in the number of successful passages. Gains in all motor control metrics were retained at 48 hours in both groups.
Published by:
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/11/484/roy484.html

