FUNCTIONAL ELECTRICAL STIMULATION (FES) METHOD AND SYSTEM TO IMPROVE WALKING AND OTHER LOCOMOTION FUNCTIONS

• US 20140128939A1
• Filed: 10/25/2012
• Published: 05/08/2014
• Est. Priority Date: 10/28/2011
• Status: Active Grant

• Current Assignee: Good Samaritan Hospital (PIH Health, Inc.)
• Original Assignee: Good Samaritan Hospital (PIH Health, Inc.)
• Inventors: Embrey, David G., Stonestreet, Jeffrey, Alon, Gadi
• Granted Patent: US 9,314,622 B2
• Time in Patent Office: Days
• US Class Current: 607/49
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/112 Gait analysis
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/6828 Leg
• CPC Class Codes: A61N 1/0452 Specially adapted for transcutaneous muscle stimulation [TMS]
• CPC Class Codes: A61N 1/0476 Array electrodes (including any electrode arrangement with more than one electrode for at least one of the polarities)
• CPC Class Codes: A61N 1/36003 of motor muscles, e.g. for walking assistance
• CPC Class Codes: A61N 1/36031 using physiological parameters for adjustment
• CPC Class Codes: A61N 1/36034 specified by the stimulation parameters

Abstract

A method and system which provides wireless, noninvasive electrical stimulation to different muscle groups to allow the user to conduct physical activities, such as walking, by stimulating various muscle groups in the body at the correct times of activation or by stimulating muscle groups in a simulation mode when standing, sitting or lying down, whereby walking is not required to stimulate the various muscle groups. The system provides a small portable wearable system which utilizes available software, including Bluetooth technology, to provide electrical nerve stimulating pulses with low current, minimal phase charge which is controlled remotely and induce desired muscle contraction with increased comfort for the user. The present method and system applies electrical stimulation with accurate timing, based on a three-dimensional motion sensor, as a trigger to initiate stimulation and which is adapted to turn itself on and off when not walking.

Claims

1. A method of determining phase charge for electrical stimulation of muscles, comprising:

providing a constant current power source;

connecting electrodes from the power source to the muscles;

determining a maximum current to be supplied depending on the muscles to be stimulated;

incrementally increasing the duration of providing the current to the muscles until contraction of the muscles is achieved.

2. The method of claim 1, wherein the muscles are lower limb muscles.

3. The method of claim 1, wherein the muscles are abdominal, back or upper limb muscles.

4. A non-invasive, wearable electrical stimulator, comprising

a controller;

a motion sensor in communication with the controller;

a power source,

a waveform generator receiving power from the power source and controlled by the controller; and

at least one pair of electrodes for applying electrical stimulation to at least one muscle, the at least one pair of electrodes electrically connected to the waveform generator for supplying electrical stimulus to peripheral nerves and muscles.

5. The electrical stimulator of claim 4, wherein the power source is a constant current power source.

6. The electrical stimulator of claim 4, further comprising a zener diode in the waveform generator.

7. The electrical stimulator of claim 4, wherein the power source includes an inductor.

8. The electrical stimulator of claim 4, wherein the motion sensor is one of a tri-axial accelerometer, a gyroscope, a magnetometer, a pressure and sound sensor.

9. The electrical stimulator of claim 4, wherein the waveform generator outputs one of a monophasic, a triple monophasic, geometrically symmetric biphasic with intra-pulse interval and triple geometrically symmetrical phasic with intra-pulse intervals waveform.

10. The electrical stimulator of claim 4, wherein the waveform generator generates a waveform which increases the intensity of stimulation, minimizes the phase charge required to activate the muscles and miniaturized the entire stimulation system.

11. The electrical stimulator of claim 8, wherein the motion sensor enables the activation of at least 2 muscle groups at the correct timing sequence regardless of the cadence of the patient.

12. The electrical stimulator of claim 8, wherein the motion sensor defines a dual-purpose trigger mechanism which turns the stimulator on when the patient is walking or practicing other locomotion for activities and off when the patient is standing, sitting or at rest.

13. A functional electrical stimulation system, comprising:

a stimulator module having a stimulation waveform generator to output an electrical signal in a stimulation pattern;

electrodes attached to the stimulation waveform generator to apply the electrical signal to a user;

a remote control unit configured to allow adjustment of the intensity of the electrical signal and to activate the stimulation waveform generator; and

an executive control unit having two way communication with the stimulator module, the executive control unit able to alter the stimulation pattern of the electrical signal and a duration of the stimulation pattern, and to collect data from the stimulation module.

14. The system of claim 13, wherein the electrical signal is a constant current signal.

15. The system of claim 14, further comprising a motion sensor in the stimulator module to activate the stimulation waveform generator.

16. The system of claim 15, wherein the motion sensor is an accelerometer.

17. The system of claim 13, wherein the remote control unit and executive control unit wirelessly communicate with the stimulator module.

18. The system of claim 13, wherein the remote control unit is a cell phone.

20. The stimulator of claim 16, wherein electrodes are connected to the stimulation waveform generator for applying the desired electrical stimulation to the muscle groups.

19. A wireless electrical stimulator for the stimulation of muscle groups of user, comprising:

a stimulator module position to electrically stimulate selected muscle groups utilizing motion of this user or a sequence of programs stimulation, said stimulator module comprising;

a motion sensor operatively associated with the stimulator module to respond to movement or other physical activity by the user which initiates the stimulation sequence, enabling the transmission of electrical stimulation pulses from the stimulation module to the muscle groups; and

a waveform generator operatively associated with the stimulator module for providing a constant current waveform electrical transmission to the muscle groups; and

a controller module operatively communicating with the stimulator module for initiating the transmission of the simulation sequence to the muscle groups.