Comparison of bilateral and unilateral training for upper extremity hemiparesis in stroke

Background. Upper extremity hemiparesis is the most common poststroke disability. Longitudinal studies have indicated that 30% to 66% of stroke survivors do not have full arm function 6 months poststroke. One promising treatment approach is bilateral training. To date, no randomized, blinded study of efficacy comparing 2 groups (bilateral training vs unilateral training) using analogous tasks has been performed in chronic stroke survivors with moderate upper extremity impairment. Objective. To compare the effectiveness of bilateral training with unilateral training for individuals with moderate upper limb hemiparesis. The authors hypothesized that bilateral training would be superior to unilateral training in the proximal extremity but not the distal one. Methods. Twenty-four subjects participated in a randomized, single-blind training study. Subjects in the bilateral group (n = 12) practiced bilateral symmetrical activities, whereas the unilateral group (n = 12) performed the same activity with the affected arm only. The activities consisted of reaching-based tasks that were both rhythmic and discrete. The Motor Assessment Scale (MAS), Motor Status Scale (MSS), and muscle strength were used as outcome measures. Assessments were administered at baseline and posttraining by a rater blinded to group assignment. Results. Both groups had significant improvements on the MSS and measures of strength. The bilateral group had significantly greater improvement on the Upper Arm Function scale (a subscale of the MAS-Upper Limb Items). Conclusion. Both bilateral and unilateral training are efficacious for moderately impaired chronic stroke survivors. Bilateral training may be more advantageous for proximal arm function.