APPARATUS FOR STIMULATING MUSCLES CONTROLLED BY THE SAME MUSCLES

• US 3,628,538 A
• Filed: 09/04/1969
• Issued: 12/21/1971
• Est. Priority Date: 09/18/1968
• Status: Expired due to Term

• Current Assignee: Armstrong David Roger, Monds Fabian Charles, Vincent Samuel Anderson
• Original Assignee: Armstrong David Roger, Monds Fabian Charles, Vincent Samuel Anderson
• Inventors: VINCENT SAMUEL ANDERSON, MONDS FABIAN CHARLES, ARMSTRONG DAVID ROGER
• Application Number:
  US04/855,281
• Time in Patent Office: 838 Days
• US Class Current: 607/62
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control
• CPC Class Codes: A61N 1/36017 with leads or electrodes penetrating the skin
• CPC Class Codes: A61N 1/36031 using physiological parameters for adjustment

Abstract

Apparatus for stimulating a muscle, using an E.M.G. signal sensed in the muscle, is described. The signal sensed is amplified, filtered and rectified before being applied to a monostable circuit which, if the E.M.G. signal is greater than a threshold value, enters its quasi-stable state. A stimulator circuit applies a voltage to electrodes adjacent to the muscle while the monostable circuit is in its quasi-stable state but the apparatus reverts to its sensing mode when the monostable circuit is in its stable state, allowing the E.M.G. signal to initiate further stimulation, if required. The apparatus is particularly useful in overcoming incontinence.

Claims

1. Apparatus for controlling muscles in living animals, including man, comprising sensing means for sensing an electromyographic signal in a muscle, stimulation means for automatically stimulating the same muscle, and control means for causing the stimulation means to stimulate the muscle only when the sensing means senses an electromyographic signal having at least a predetermined magnitude.

2. Apparatus according to claim 1 wherein the control means causes the stimulation means to terminate the stimulus signal after a predetermined interval to allow the sensing means to sense a further electromyographic signal.

3. Apparatus according to claim 2 including a pair of electrodes adapted to be mounted on an animal'"'"''"'"'s body adjacent to a muscle to be stimulated, the electrodes being coupled to the sensing means as a part thereof to pick up electromyographic signals, and to the stimulation means as a part thereof to receive a voltage and apply the voltage to stimulate the muscle.

4. Apparatus according to claim 3 wherein the sensing means includes a differential amplifier with two input terminals one connected to each electrode.

5. Apparatus according to claim 2, wherein the sensing means is most sensitive to a signal of frequency between 100 to 200 Hz., and is least sensitive to signals having frequencies below 100 Hz. and above 1,000 Hz.

6. Apparatus according to claim 2, wherein the control means include a monostable circuit and the stimulation means include a pulse oscillator, the monostable circuit being coupled to the sensing means to take up its quasi-stable state when the electromyographic signal reaches the predetermined level, and the monostable circuit being coupled to the oscillator to allow oscillation only when the monostable circuit is in its quasi-stable state.

7. Apparatus according to claim 6 wherein the sensing means includes a rectificatiOn for providing a DC signal from the sensed signal for application to the monostable circuit, the magnitude of the DC signal determining whether or not the monostable circuit enters its quasi-stable state.

8. Apparatus according to claim 6 including a transformer having primary and secondary windings and including a pair of electrodes adapted to be mounted on an animal'"'"''"'"'s body adjacent to a muscle to be stimulated, the electrodes being coupled to the sensing means as a part thereof to pick up electromyographic signals, and to the stimulation means as a part thereof to receive a voltage and apply the voltage to stimulate the muscle, where the oscillator output is connected to the primary winding of said transformer whose secondary winding is connected to the electrodes.

9. Apparatus according to claim 3 wherein the sensing means is constructed to sense levator ani muscles, including the anal sphincter, and other muscles of the pelvic floor.