Effect of a Novel Perturbation-Based Pinch Task Training on Sensorimotor Performance of Upper Extremity for Patients With Chronic Stroke: A Pilot Randomized Controlled Trial

Objective: To investigate the effects of perturbation-based pinch task training on the sensorimotor performance of the upper extremities of patients with chronic stroke via a novel vibrotactile therapy system. Design: A single-blinded randomized controlled trial. Setting: A university hospital. Participants: Patients with chronic stroke (N=19) randomly assigned into either an experimental group or a control group completed the study. Interventions: In addition to 10 minutes of traditional sensorimotor facilitation, each participant in the experimental group received 20 minutes of perturbation-based pinch task training in each treatment session, and the controls received 20 minutes of task-specific motor training twice a week for 6 weeks. Main Outcome Measures: The scores for the primary outcome, Semmes-Weinstein monofilament (SWM), and those for the secondary outcomes, Fugl-Meyer Assessment (FMA), amount of use, quality of movement (QOM) on the Motor Activity Log (MAL) scale, and box and block test (BBT), were recorded. All outcome measures were recorded at pretreatment, post treatment, and 12-week follow-up. Results: There were statistically significant between-group differences in the training-induced improvements revealed in the SWM results (P=.04) immediately after training and in the BBT results (P=.05) at the 12-week follow-up. The changes in muscle tone and in the QOM, SWM, and BBT scores indicated statistically significant improvements after 12 sessions of treatment for the experimental group. For the control group, a significant statistical improvement was found in the wrist (P<.001) and coordination (P=.01) component of the FMA score. Conclusions: This study indicated that the perturbation-based pinch task training has beneficial effects on sensory restoration of the affected thumb in patients with chronic stroke.