Effect of Microelectronic Electromyography Bridge on Motor Function of Extensor Carpi Radialis Longus in Patients with Cervical Spinal Cord Injury / 中国康复理论与实践

Objective:To observe the effect of microelectronic EMG bridge (EMGB) training on the motor function of extensor carpi radialis longus in patients with complete cervical 5 spinal cord injury. Methods:From March, 2016 to March, 2017, 20 patients with complete cervical 5 spinal cord injury were randomly divided into control group (n = 10) and experimental group (n = 10). The control group received routine wrist extensor muscle training, and the experimental group received EMGB training in addition, for 180 days. The motor function of the affected limb was evaluated by sEMG of extensor carpi radialis longus, Manual Muscle Test (MMT), Wolf Motor Function Test (WMFT) and Spinal Cord Lesion Independence Measure (SCIM). Results:After treatment, the peak value and average value of sEMG of extensor carpi longus of both sides increased in both groups (t > 2.510, P < 0.05), the peak value and average value of the left side were higher (t > 2.759, P < 0.05), and the peak value of the right side was higher (t = 2.691, P < 0.05) in the experiment group than in the control group, however, there was no significant difference in average value of the right side between two groups (t = 2.063, P = 0.054). The scores of MMT increased in both groups (t > 2.569, P < 0.05), and were higher in the experimental group than in the control group (t > 2.278, P < 0.05). The scores of WMFT and SCIM increased in both groups (t > 3.839, P < 0.05), however, there was no significant difference between two groups (t < 1.498, P > 0.05). Conclusion:EMGB training could improve the motor function of extensor carpi radialis longus in patients with complete cervical 5 spinal cord injury.

System design and experimental research of lower esophageal sphincter stimulator for treatment of gastroesophageal reflux disease.

Electrical stimulation therapy (EST) of lower esophageal sphincters (LES) is a new technique for the treatment of gastroesophageal reflux disease (GERD). In this paper, an implantable LES stimulator with wireless power transmission is proposed for the treatment of GERD. The LES stimulator is composed of an implantable pulse generator (IPG), an external controller, and a wireless power transmission module. The IPG, whose area is 31×21 mm2, is designed to generate voltage-regulated constant-current stimulation pulses. The external controller allows for wireless programming of the IPG via a Bluetooth Low Energy (BLE) module. The wireless power transmission module provides power for the IPG. According to the measurement of output stimulus waveforms, the proposed LES stimulator is capable of delivering electrical stimulations with a current ranging between 0 and 8 mA. To evaluate the safety and efficacy of the proposed LES stimulator, experiments were performed on 12 male New Zealand white rabbits. Esophageal manometry was performed before and after the procedure and the LES pressure (LESP) has been recorded. The mean LESP is increased significantly in the stimulation group than the sham group (stimulation group: 9.25±1.24 mmHg vs 13.99 ±1.28 mmHg, p<;0.05; sham group: 9.00±1.22 mmHg vs 9.23±1.27 mmHg, p=0.267). The results show that the electrical stimulation delivered by the LES stimulator can safely and effectively increase resting LES pressure in acute animal models, suggesting that the implantable LES stimulator is a perspective approach for treating GERD in clinics.

Electromyographic Bridge-a multi-movement volitional control method for functional electrical stimulation: prototype system design and experimental validation.

The voluntary participation of the paralyzed patients is crucial for the functional electrical stimulation (FES) therapy. In this study, we developed a strategy called "EMG Bridge" (EMGB) for volitional control of multiple movements using FES technique. The surface electromyography (sEMG) signals of the agonist muscles were transformed to stimulation pulses with various pulse width and frequency to stimulate the target paralyzed muscles using MAV/NSS co-modulation (MNDC) algorithm we proposed recently. Motion pattern classification based on linear discriminant analysis (LDA) was included to recognize the motion status and mapping the sEMG detection channel to the corresponding stimulation channel. A prototype EMGB system was built for real-time control of four hand movements. The test results showed that the movements can be reproduced with a successful rate of 92.5±3.5%. The angle trajectory of wrist joint and metacarpal-phalangeal joint can be mimicked with a maximum cross-correlation coefficient > 0.84 and a latency less than 300 ms.

Design of sEMG-detecting circuit for EMG-Bridge.

A surface electromyography (sEMG) signal typically results from the electrical activities of many muscle fibers, and can be utilized as a signal source in prostheses due to its abundance of movement information. This paper proposes an sEMG-detection circuit for the acquisition of the controlling signal in EMG-Bridge (EMGB) systems. The detection circuit mainly comprises a preamplifier, a driven right leg (DRL) circuit, a high-pass filter (HPF), a low-pass filter (LPF), and a gain adjustable amplifying circuit. The common-mode rejection ratio (CMRR) of the circuit is higher than 120 dB, the input impedance is greater than 100 MΩ, the passband range is 20~450 Hz, and the frequency attenuation in stopband is not less than 120dB/dec.

A wearable multi-pad electrode prototype for selective functional electrical stimulation of upper extremities.

In this paper, a surface multi-pad stimulation electrode with selective characteristics was designed, it was safe to use and easy to mount. Then a wearable and distributed multi-pad functional electrical stimulation (FES) prototype combined with sensing, communication and smart technology was designed, which can achieve a fast, intelligent optimization to determine stimulation electrode sites and comfortable stimulation. In addition, in order to improve the application and convenience of FES in the rehabilitation at clinical and home-setting, an Android application (APP) based on smart phone was designed for running an algorithm of searching optimal stimulation site. The prototype has been validated by performing selective stimulation on one healthy subject, and showed that the FES system can automatically determine the stimulation site.

Study on signal transmission characteristics of meridian based on electrical network theory and experiments / 中国针灸

Study on features of acupoints with resistance test in the past half century is reviewed in this article. Mechanism and technology of the method are introduced as well as its shortcomings. The determination method of signal transmission along meridians with the combination of electrical network theories and practice is advanced. And the result of a series experiments on one meridian at the superficial part of the body are given as well. Thus, it is concluded that the signals of the point-in/point-out and the signals along a non-meridian path with the same distance are significantly different, which gives a verification of the feasibility of the method by using electrical network theories to set out characteristics of signal transmission along meridians dynamically.

Function electrical stimulation signals generator circuits for the central nerve and the sciatic nerve.

Circuits for the signal generation of the FES (functional electrical stimulation) of the central nerve and the sciatic nerve have been designed. The circuits were implemented by using discrete devices. The FES circuits consist of two or three operational amplifiers. The bandwidths of the circuits are more than 10 kHz and their gains are variable from 20 dB to 60 dB. To a load of several kilo-ohms, according to the microelectrode with the nerve, the circuit for stimulating central nerve can provide a current signal, and the signal value is more than 1mA. The circuit for stimulating sciatic nerve can provide a stimulating voltage signal of more than 10 Vs. The loads of the circuits are microelectrodes contacted with nerves. The circuits can be used with two kinds of microelectrodes: cuff microelectrodes which for stimulating sciatic nerve and shaft microelectrodes which for stimulating central nerve.