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Stroke is the leading cause of long-term disability among adults. Adequate rehabilitation of the upper extremity in stroke patients can improve performance in activities of daily living. Robot-assisted therapy can offer intense, repetitive, and task-specific training to the impaired limb after stroke. Prior studies have shown that robot-assisted therapy may improve strength and motor deficits of the impaired limbs, but there is a lack of research comparing the effects of unilateral robot-assisted training protocol (URTP) versus bilateral robot-assisted training protocol (BRTP) with a robotic device. Comparison of the effectiveness of these two protocols is beneficial to determine the appropriate treatment choice for individual patients. This study used a robotic device called the Bi-Manu-Track to determine the effectiveness of both unilateral and bilateral robotic therapy protocols on motor impairment, muscle power, and muscle strength.

The population for this study was adults who had had single or repetitive unilateral cerebral strokes resulting in hemiparesis. The intervention included exercises in forearm pronation and supination, as well as wrist flexion and extension, with the Bi-Manu-Track robotic device. Three therapy groups were compared: unilateral robotic therapy, bilateral robotic therapy, and a control group that received routine occupational therapy. All training sessions were conducted by trained occupational therapists, and participants in all three groups received 90–105 min of training per day, 5 days per week, for a total of 4 weeks.

The researchers of this study found that the URTP and BRTP groups had greater improvements in motor impairment, muscle power, and strength than did the control group. The URTP seemed to be more effective in improving motor impairment and muscle power at the distal joints than the other two groups. Conversely, the BRTP brought about greater improvement in muscle power at the proximal joints than did the URTP and traditional occupational therapy. All participants in the study improved on grip strength, with no statistically significant differences among the three groups. Overall, robotic-assisted training protocols can provide the intensive repetitive movements and task-specific interventions that are needed for upper extremity rehabilitation poststroke. On the basis of the results of this study, both URTP and BRTP can be effective interventions in upper extremity rehabilitation for patients after stroke. The results of this study show different outcomes in motor impairment, motor power, and strength for unilateral versus bilateral training protocols. Therapists using the Bi-Manu-Track are advised to select the specific protocol that will target improvement for their patients. More studies should be conducted with a larger sample size to further fill in the gaps of knowledge about robot-assisted training for individualized therapy.


A product of the American Occupational Therapy Association's Evidence-based Literature Review Project.


Copyright © 2016 American Occupational Therapy Association. All Rights Reserved. Reproduced here with permission.

Publisher's Statement

Originally published as: Mandrussow, M., Keshishyan, A., & Li, K. (2016) Pilot Comparative Study of Unilateral and Bilateral Robot-Assisted Training on Upper-Extremity Performance in Patients With Stroke. American Journal Of Occupational Therapy, 66(2). Bethesda, MD: American Occupational Therapy Association, Evidence-Based Practice Project.