Effect of Dual Therapy with Botulinum Toxin A Injection and Electromyography-controlled Functional Electrical...

Area of Science:

• Neurorehabilitation
• Movement Science
• Biomedical Engineering

Background:

• Botulinum toxin A (BTX-A) injections are known to reduce spasticity.
• However, BTX-A alone or with adjuvant therapy shows limited improvement in functional movement for spastic upper extremity paralysis.
• This highlights the need for combined therapeutic strategies.

Purpose of the Study:

• To determine the effectiveness of task-oriented therapy using electromyography-triggered functional electrical stimulation (EMG-FES) after BTX-A injections.
• To assess the impact on spasticity and functional upper limb movement.
• To evaluate the potential for improved muscle re-education and daily living activities.

Main Methods:

• An open-label, prospective clinical trial was conducted on 15 patients with spastic paresis (stroke or spinal cord injury).
• Patients received BTX-A injections followed by 4 months of task-oriented therapy with EMG-FES.
• Outcomes were assessed using the modified Ashworth scale, hand function tests, and grip strength at baseline, 10 days, and 4 months post-injection.

Main Results:

• Median modified Ashworth scale scores significantly decreased post-injection, indicating reduced spasticity.
• Finger individual movement test scores showed a significant increase at 4 months.
• While some functional tests initially decreased, most showed significant improvement by the 4-month mark, suggesting functional recovery.

Conclusions:

• Task-oriented therapy with EMG-FES following BTX-A injection is effective in reducing spasticity and enhancing upper limb motor function.
• Spasticity may serve as a compensation for muscle weakness, leading to maladaptive movement patterns.
• The combination therapy potentially re-educates physiological movement patterns, beneficial for activities of daily living.