Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method

Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method.Through a series of novel design concepts,including the integration of a detecting circuit and an analog-to-digital converter,a miniaturized functional electrical stimulation circuit technique,a low-power super-regeneration chip for wireless receiving,and two wearable armbands,a prototype system has been established with reduced size,power,and overall cost.Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects,the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy.Test results showed that wrist flexion/extension,hand grasp,and finger extension could be reproduced with high accuracy and low latency.This system can build a bridge of information transmission between healthy limbs and paralyzed limbs,effectively improve voluntary participation of hemiplegic patients,and elevate efficiency of rehabilitation training.

Single fiber electromyography in the diagnosis of ocular myasthenia gravis:report of 90 cases

Background The aim of this study was to evaluate single fiber electromyography (SFEMG) in the diagnosis of ocular myasthenia gravis (OMG),compared with repetitive nerve stimulation (RNS) and blood concentration of antibody to acetylcholine receptor (AchRAb).Methods SFEMG,RNS and AchRAb titration were measured in 90 patients with OMG (44 men,46 women). Results Markedly increased jitter and ratio of block in the frontalis and the extensor digitorum communis (EDC) were observed (83.3% and 61.1%,respectively). The mean jitter was 43.6±14.5 μs,and the percentages of jitter>55 μs and blocking were 16.9%±19% and 3.5%±9.5% respectively in the EDC. The mean jitter was 64.3±25.6 μs,and the percentages of jitter >55 μs and blocking were 33.5%±27.6% and 29.3%±23.2% respectively in the frontalis. The percentage of abnormal RNS was 27.8% (25/90). There was an increased AchRAb titration in 29 (32.2%) of the 90 patients. Increased jitter,blocking was negatively correlated with maximum decrement to RNS ( P <0.01). 11.4% (4/35) of patients with abnormal RNS and 24.1% (7/29) patients with abnormal AchRAb were seen in the patients with normal SFEMG in the EDC. Conclusion SFEMG test showed the highest sensitivity in the diagnosis of OMG. To our knowledge, the three methods (SFEMG,RNS and AchRAb) are complementary in the diagnosis and differential diagnosis of OMG.