The effect of task-oriented electromyography-triggered electrical stimulation of the paretic wrist extensors on upper limb motor function early after stroke: a pilot randomized controlled trial

The combined effect of task-oriented motor training and electromyography (EMG)-triggered electrical stimulation (ES) has been examined in chronic stroke, but there are no published reports in patients with early stroke. Therefore, the purpose of this study was to determine the short-term and long-term effects of task-oriented EMG-triggered ES on upper limb motor function in acute/subacute stroke. Twenty-seven patients with stroke within the first 3 months after stroke onset were randomly allocated to an experimental group and a control group. Twenty-three patients (12 patients in the experimental group and 11 patients in the control group) completed the study. The control group received a conventional physical therapy for 20 sessions, and the experimental group received task-oriented EMG-triggered ES therapy for the wrist/finger extensors in addition to conventional physical therapy for 5 sessions a week for 4 weeks. Primary outcome measures were the Action Research Arm Test, the Brunnstrom stages of the hand/upper extremity, and the motor Functional Independence Measure. All patients were evaluated before the treatment, after the treatment, and at 3 months. The parametric and nonparametric statistics at the 5% level of significance (alpha=0.05) was used for testing the differences between the two groups at each main end point. At the end of the treatment, the experimental group showed significantly greater improvements in Brunnstrom stages and ARAT grasp/grip/pinch scores, but not motor Functional Independence Measure scores, when compared with the control group. The differences between the 3-months and postintervention evaluations were not significant between the two groups suggesting retention of the postintervention gains. Our results indicate that task-oriented EMG-triggered ES training may result in improvements in the paretic upper limb function in patients with acute/subacute stroke that are superior to the conventional treatment.