Systems and methods to place one or more leads in tissue to electrically stimulate nerves to treat pain
It has been discovered that pain felt in a given region of the body can be treated, not by motor point stimulation of muscle in the local region where pain is felt, but by stimulating muscle spaced from a “nerve of passage” in a region that is superior (i.e., cranial or upstream toward the spinal column) to the region where pain is felt. Spinal nerves such as the intercostal nerves or nerves passing through a nerve plexus, which comprise trunks that divide by divisions and/or cords into branches, comprise “nerves of passage.”
1. A method comprising the steps of:
providing an introducer needle preloaded with a coiled lead having an insulated portion and an electrode formed from a deinsulated portion;
percutaneously inserting the introducer needle into a body at an angle at a puncture site;
depositing the electrode outside a spinal column in a region having a spinal nerve that is between a painful region and a center of the body of a patient,
placing a surface stimulation return electrode on the body;
electrically coupling the coiled lead to a pulse generator;
coupling the surface stimulation return electrode to the pulse generator; and
stimulating the spinal nerve to recruit target fibers in the spinal nerve while minimizing recruitment of non-target fibers in the spinal nerve, wherein the electrode is within electrical proximity to and physically spaced from the spinal nerve.
2. The method of claim 1 further comprising applying a test stimulation to the spinal nerve to recruit target fibers in the spinal nerve while minimizing recruitment of non-target fibers in the spinal nerve.
3. The method of claim 1 , wherein the electrode is positioned about 100 millimeters from the spinal nerve.
4. The method of claim 1 , wherein the stimulating of the spinal nerve comprises application of electrical stimulation having stimulation parameters of 4 mA, 100 μs, 100 Hz, and an on-off duty cycle of 0.25 sec.
5. The method of claim 1 further comprising advancing the introducer needle until a patient reports an evoked sensation in the painful region.
6. The method of claim 5 further comprising increasing a stimulus amplitude until a stimulation-evoked tingling sensation expands to overlay the painful region.
7. The method of claim 5 further comprising varying a stimulus amplitude in increments of no more than 0.5 mA until a stimulation-evoked tingling sensation is evoked.
8. The method of claim 1 further comprising confirming location of the electrode via an imaging technique.
9. The method of claim 8 , wherein the imaging technique comprises at least one of ultrasound, fluoroscopy and X-ray.
10. A method comprising the steps of:
providing an introducer needle preloaded with a coiled lead having an insulated portion and an electrode formed from a deinsulated portion;
percutaneously inserting the introducer needle into a body at a puncture site;
depositing the electrode outside a spinal column in a region having a spinal nerve that is between a painful region and a center of the body of a patient,
placing a surface stimulation return electrode on the body;
coupling the coiled lead to a pulse generator;
coupling the surface stimulation return electrode to the pulse generator; and
stimulating the spinal nerve to recruit target fibers in the spinal nerve while minimizing recruitment of non-target fibers in the spinal nerve.
11. The method of claim 10 further comprising withdrawing the introducer needle and leaving the electrode in electrical proximity to the spinal nerve.
12. The method of claim 10 , wherein the introducer needle is insulated along a length of a shaft except for an area that corresponds with an exposed conduction surface of the electrode.
13. The method of claim 10 , wherein the introducer needle is between 17 gauge and 26 gauge.
14. A method comprising the steps of:
percutaneously inserting a coiled lead having an insulated portion and at least one electrode formed from a deinsulated portion, into a body outside a spinal column having a spinal nerve that is between a painful region and a center of the body of a patient, and
stimulating the spinal nerve to recruit target fibers in the spinal nerve while minimizing recruitment of non-target fibers in the spinal nerve, wherein the at least one electrode is within electrical proximity to and physically spaced from the spinal nerve.
15. The method of claim 14 further comprising coupling the coiled lead to an external pulse generator.
16. The method of claim 15 , wherein the electrode of the coiled lead is spherical.
17. The method of claim 16 further comprising:
removing the coiled lead from the external pulse generator;
implanting an implantable pulse generator; and
stimulating the spinal nerve to recruit target fibers in the spinal nerve while minimizing recruitment of non-target fibers in the spinal nerve.
18. The method of claim 17 further comprising:
removing the coiled lead from the body;
implanting an implantable electrode within electrical proximity to and physically spaced from the spinal nerve; and
operatively coupling the implantable electrode with the implantable pulse generator.
19. The method of claim 18 , wherein the stimulation applied to the spinal nerve comprises at least one stimulation parameter and the at least one stimulation parameter is adjustable through an external controller.
20. The method of claim 19 , wherein an external pulse generator applies the stimulation to the spinal nerve and the external pulse generator comprises an external controller.