Functional electrical stimulation system

• US 20040082979A1
• Filed: 10/23/2002
• Published: 04/29/2004
• Est. Priority Date: 10/23/2002
• Status: Active Grant

• Current Assignee: Hong Kong Polytechnic University
• Original Assignee: Hong Kong Polytechnic University
• Inventors: Mak, Arthur F. T., Leung, Kelvin T. Y., Tong, Kai-Yu
• Granted Patent: US 7,162,305 B2
• Time in Patent Office: Days
• US Class Current: 607/48
• CPC Class Codes: A61N 1/0452 Specially adapted for transcutaneous muscle stimulation [TMS]
• CPC Class Codes: A61N 1/0484 Garment electrodes worn by the patient
• CPC Class Codes: A61N 1/36003 of motor muscles, e.g. for walking assistance

Abstract

An electrical stimulation device for a body part of a person comprises an orthotic with sensor and electrodes and a controller. The controller receives a sensor signal, compares the sensor signal to a threshold value and generates an electrical output from the electrodes if the sensor signal exceeds the threshold value. A docking station facilitates connection of the electrodes and sensors to a computer. The docking station including a first processor for measuring values of the sensor signal and the electrical outputs and a second processor for generating electrical outputs on the electrodes.

Claims

1. An electrical stimulation device comprising:

an orthotic for a body part of a person,

a sensor on the orthotic for detecting movement of the body part,

an electrode on the orthotic for contacting the skin surface over a muscle of the body part, and

a controller in electrical communication with the sensor and electrode for receiving a sensor signal, comparing the sensor signal to a threshold value and generating an electrical output from the electrode if the sensor signal exceeds the threshold value.

2. An electrical stimulation device comprising:

an orthotic for a body part of a person,

a first sensor on the orthotic for detecting a first movement of the body part

a second sensor on the orthotic for detecting a second movement of the body part,

a plurality of electrodes on the orthotic for contacting the skin surface over muscles of the body part, and

a controller in electrical communication with the sensors and electrodes for receiving a first sensor signal and comparing it to a first threshold value, receiving a second sensor signal and comparing it to a second threshold value, and generating an electrical output from a first group of electrodes if the first sensor signal exceeds the first threshold value, or generating the electrical output from a second group of electrodes if the first sensor signal exceeds the first threshold value and the second sensor signal exceeds the second threshold value.

3. The devise of claim 2 wherein the body part is an upper limb, the first movement is extension of the wrist, the second movement is rotation of the wrist, and the muscles are thumb abductor, thenar, wrist extensor, and wrist flexor muscles.

4. The device of claim 2 wherein the first sensor is an accelerometer and the first movement is extension of the wrist, and second sensor is a gyroscope and the second movement is rotation of the wrist.

5. The device of claim 2 wherein the orthotic includes a first elongate member for locating on a anterior portion of a forearm of the person, a dorsal strap extending across a posterior portion of the forearm, a second elongate member disposed on the dorsal strap of locating against the posterior portion of the forearm, and a hand member for locating about a wrist and palm of the person, the wrist member being flexibly engaged with the first elongate member for allowing movement of the wrist.

6. The device of claim 2 including a docking station for connecting the electrodes and sensors to a computer, the docking station including a first processor for measuring values of the sensor signals and the electrical output and communicating said values to the computer, and a second processor for generating electrical outputs on the electrodes in response to communications from the computer.

7. The device of claim 2 wherein the controller is connectable to the computer for uploading parameters including the first and second threshold values from the computer to the controller.

8. The device of claim 2 wherein the first group of electrodes are located on the skin surface over the thumb abductor and wrist extensor muscles, and the second group of electrodes are located on the skin surface over the Thenar and wrist extensor muscles.

9. A method of controlling movement of a body part of a person including the steps of:

detecting a movement of a body part,

generating a signal proportional to the movement,

comparing the signal to a threshold value, and

delivering an electric current to a muscle in the body part for a predetermined time if the signal exceeds the threshold value.

10. The method of claim 9 including an intermediate step of:

detecting a second movement of the body part,

generating a second signal proportional to the second movement,

comparing the second signal to a second threshold value, and wherein

the electric current is delivered to a second muscle in the body part if the signal exceeds the threshold value and the second signal exceeds the second threshold value.