Coordinated upper limb training assisted with an electromyography (EMG)-driven hand robot after stroke

Area of Science:

• Neurorehabilitation
• Robotics in Medicine
• Biomechanics

Background:

• Stroke survivors often experience impaired muscular coordination and spasticity, limiting upper limb function.
• Traditional rehabilitation methods may not fully restore motor control after chronic stroke.
• Electromyography (EMG)-driven robotic systems offer a promising avenue for targeted motor retraining.

Purpose of the Study:

• To investigate the effectiveness of an EMG-driven hand robot for whole upper limb training in individuals with chronic stroke.
• To assess the impact of robot-assisted training on muscular coordination and spasticity.
• To evaluate improvements in motor control and functional recovery.

Main Methods:

• Ten individuals with chronic stroke participated in a 20-session training program using an EMG-driven hand robot.
• Training involved object grasp/release and arm transportation tasks, guided by real-time EMG feedback.
• Muscle co-contractions and excessive muscle activities were measured using EMG signals.
• Spasticity was assessed using the Modified Ashworth Scale.

Main Results:

• Significant improvements in muscle co-ordination were observed between antagonist muscle pairs (flexor digitorum and extensor digitorum), indicated by reduced muscle co-contractions.
• Excessive muscle activity in the biceps brachii was reduced, suggesting more efficient motor control.
• A notable reduction in finger spasticity was measured using the Modified Ashworth Scale.

Conclusions:

• EMG-driven hand robot therapy is effective in improving muscular coordination in the upper limb of chronic stroke survivors.
• This robotic approach can help mitigate excessive muscle activation and reduce spasticity, contributing to functional recovery.
• Hand robot-assisted training holds potential as an adjunct therapy for post-stroke rehabilitation, enhancing motor control and quality of life.