Abstract
Background
Abnormal upper arm-forearm muscle synergies after stroke are poorly understood. We investigated whether upper arm function primes paralyzed forearm muscles in chronic stroke patients after Brain-Machine Interface (BMI)-based rehabilitation. Shaping upper arm-forearm muscle synergies may support individualized motor rehabilitation strategies.
Methods
Thirty-two chronic stroke patients with no active finger extensions were randomly assigned to experimental or sham groups and underwent daily BMI training followed by physiotherapy during four weeks. BMI sessions included desynchronization of ipsilesional brain activity and a robotic orthosis to move the paretic limb (experimental group, n = 16). In the sham group (n = 16) orthosis movements were random. Motor function was evaluated with electromyography (EMG) of forearm extensors, and upper arm and hand Fugl-Meyer assessment (FMA) scores. Patients performed distinct upper arm (e.g., shoulder flexion) and hand movements (finger extensions). Forearm EMG activity significantly higher during upper arm movements as compared to finger extensions was considered facilitation of forearm EMG activity. Intraclass correlation coefficient (ICC) was used to test inter-session reliability of facilitation of forearm EMG activity.
Results
Facilitation of forearm EMG activity ICC ranges from 0.52 to 0.83, indicating fair to high reliability before intervention in both limbs. Facilitation of forearm muscles is higher in the paretic as compared to the healthy limb (p<0.001). Upper arm FMA scores predict facilitation of forearm muscles after intervention in both groups (significant correlations ranged from R = 0.752, p = 0.002 to R = 0.779, p = 0.001), but only in the experimental group upper arm FMA scores predict changes in facilitation of forearm muscles after intervention (R = 0.709, p = 0.002; R = 0.827, p<0.001).
Conclusions
Residual upper arm motor function primes recruitment of paralyzed forearm muscles in chronic stroke patients and predicts changes in their recruitment after BMI training. This study suggests that changes in upper arm-forearm synergies contribute to stroke motor recovery, and provides candidacy guidelines for similar BMI-based clinical practice.
Original language | English |
---|---|
Article number | e0140161 |
Journal | unknown |
Volume | unknown |
Issue number | 10 |
DOIs | |
Publication status | Published - 23 Oct 2015 |
Keywords
- UPPER-EXTREMITY
- UPPER-LIMB
- CORTICAL DAMAGE
- RECOVERY
- POSTSTROKE
- HEMIPARESIS
- SYNERGIES
- SURVIVORS
- BCI
- EMG
Project and Funding Information
- Project ID
- info:eu-repo/grantAgreement/EC/FP7/231724/EU/HUman behavioral Modeling for enhancing learning by Optimizing hUman-Robot interaction/HUMOUR
- Funding Info
- German Federal Ministry of Education and Research (BMBF), _x000D_ Deutsche Forschungsgemeinschaft (DFG),_x000D_ European Research Council,_x000D_ European Union Information and Communication Technologies Framework Programme 7 (ICT-FP7),_x000D_ TECNALIA, _x000D_ Baden Wuerttemberg Stiftung,_x000D_ Natural Science Foundation of China,_x000D_ Volkswagen Stiftung,_x000D_ CAPES (Coordination for the Improvement of Higher Level -or Education-Personnel, Brazil),_x000D_ CNPq (Brazilian National Counsel of Technological and Scientific Development),_x000D_ DAAD (Deutscher Akademischer Austauschdienst),_x000D_ Interuniversity Center for the Research in Cognitive Processing of Natural and Artificial Systems (ECoNa),_x000D_ Sapienza University of Rome