Methods for electrosurgical treatment of intervertebral discs

• US 6,264,650 B1
• Filed: 05/21/1999
• Issued: 07/24/2001
• Est. Priority Date: 06/07/1995
• Status: Expired due to Term

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Eggers, Philip E., Hovda, David C., Ellsberry, Maria B., Thapliyal, Hira V.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US09/316,472
• Time in Patent Office: 795 Days
• Field of Search: 606/32, 606/34, 606/41, 606/46, 606/49, 606/50, 607/99, 607/105, 607/113, 604/35, 604/114
• US Class Current: 606/32
• CPC Class Codes: A61B 18/042 using additional gas becoming plasma
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1477 Needle-like probes
• CPC Class Codes: A61B 18/148 having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy
• CPC Class Codes: A61B 18/1482 having a long rigid shaft for accessing the inner body transcutaneously in minimal invasive surgery, e.g. laparoscopy
• CPC Class Codes: A61B 18/1485 having a short rigid shaft for accessing the inner body through natural openings
• CPC Class Codes: A61B 18/149 bow shaped or with rotatable body at cantilever end, e.g. for resectoscopes, or coagulating rollers
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 2017/00026 Conductivity or impedance, e.g. of tissue
• CPC Class Codes: A61B 2017/00084 Temperature
• CPC Class Codes: A61B 2017/00101 using an array of thermosensors
• CPC Class Codes: A61B 2017/00247 Making holes in the wall of the heart, e.g. laser Myocardial revascularization
• CPC Class Codes: A61B 2017/00261 Discectomy
• CPC Class Codes: A61B 2017/00274 Prostate operation, e.g. prostatectomy, turp, bhp treatment
• CPC Class Codes: A61B 2018/00029 open
• CPC Class Codes: A61B 2018/00083 low, i.e. electrically insulating
• CPC Class Codes: A61B 2018/00119 with metal oxide nitride
• CPC Class Codes: A61B 2018/0016 Energy applicators arranged in a two- or three dimensional array
• CPC Class Codes: A61B 2018/00178 Electrical connectors
• CPC Class Codes: A61B 2018/00291 : using suction
• CPC Class Codes: A61B 2018/00327 : Ear, nose or throat
• CPC Class Codes: A61B 2018/00392 : Transmyocardial revascularisation
• CPC Class Codes: A61B 2018/00434 : Neural system
• CPC Class Codes: A61B 2018/0044 : Spinal cord
• CPC Class Codes: A61B 2018/00505 : Urinary tract
• CPC Class Codes: A61B 2018/00547 : Prostate
• CPC Class Codes: A61B 2018/00577 : Ablation
• CPC Class Codes: A61B 2018/00583 : Coblation, i.e. ablation using a cold plasma
• CPC Class Codes: A61B 2018/00589 : Coagulation
• CPC Class Codes: A61B 2018/00607 : Coagulation and cutting with the same instrument
• CPC Class Codes: A61B 2018/00678 : upper
• CPC Class Codes: A61B 2018/00702 : Power or energy
• CPC Class Codes: A61B 2018/00726 : Duty cycle
• CPC Class Codes: A61B 2018/00791 : Temperature
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00982 : combined with or comprising means for visual or photographic inspections inside the body, e.g. endoscopes
• CPC Class Codes: A61B 2018/1213 : creating an arc
• CPC Class Codes: A61B 2018/124 : switching the output to different electrodes, e.g. sequentially
• CPC Class Codes: A61B 2018/1253 : monopolar
• CPC Class Codes: A61B 2018/126 : bipolar
• CPC Class Codes: A61B 2018/1273 : including multiple generators in one device
• CPC Class Codes: A61B 2018/1425 : Needle
• CPC Class Codes: A61B 2018/1467 : using more than two electrodes on a single probe
• CPC Class Codes: A61B 2018/1472 : for use with liquid electrolyte, e.g. virtual electrodes
• CPC Class Codes: A61B 2018/162 : located on the probe body
• CPC Class Codes: A61B 2018/165 : Multiple indifferent electrodes
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61B 90/11 : with guides for needles or instruments, e.g. arcuate slides or ball joints
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices

Abstract

Systems, apparatus and methods for ablation, resection, aspiration, collagen shrinkage and/or hemostasis of tissue and other body structures in open and endoscopic spine surgery. In particular, the present invention includes a channeling technique in which small holes or channels are formed within spinal discs, and thermal energy is applied to the tissue surface immediately surrounding these holes or channels to cause thermal damage to the tissue surface, thereby stiffening the surrounding tissue structure and for reducing the volume of the disc to relieve pressure on the surrounding nerves. High frequency voltage is applied between one or more active electrode(s) and one or more return electrode(s) to volumetrically remove or ablate at least a portion of the disc tissue, and the active electrode(s) are advanced through the space left by the ablated tissue to form a channel, hole, divot or other space in the disc tissue. In addition, the high frequency voltage effects a controlled depth of thermal heating of the tissue surrounding the hole to thermally damage or create a lesion within the tissue surrounding the hole to debulk and/or stiffen the disc structure, thereby relieving neck or back pain.

Claims

1. A method for treating intervertebral discs:

positioning an active electrode adjacent to, or within, a disc;

applying high frequency voltage between the active electrode and a return electrode, the high frequency voltage being sufficient to ablate the disc tissue;

during the applying step, advancing the active electrode into the disc tissue to generate a space within the disc tissue; and

removing the active electrode from the space within the disc tissue.

2. The method of claim 1 further comprising, during the removing step, applying high frequency voltage between the active and return electrodes, the high frequency voltage being sufficient to coagulate blood at the tissue surface surrounding the space.

3. The method of claim 2 wherein the high frequency voltage during the applying step is sufficient to thermally damage the surface of the disc tissue surrounding the space.

4. The method of claim 1 further comprising providing an electrically conductive fluid around the active electrode and between the active and return electrodes prior to the applying step.

5. The method of claim 4 wherein the providing step comprises positioning the active and return electrodes within a supply of electrically conductive fluid and then positioning the active and return electrodes adjacent to the disc.

6. The method of claim 4 wherein the providing step comprises delivering the electrically conductive fluid to the active and return electrodes.

7. The method of claim 4 wherein the electrically conductive fluid is a liquid.

8. The method of claim 4 further comprising generating a current flow path between the active and return electrodes with the electrically conductive fluid.

9. The method of claim 4 further comprising aspirating fluid from a region around the active electrode.

10. The method of claim 1 further comprising applying a sufficient high frequency voltage difference between the active and return electrodes to effect molecular dissociation of at least a portion of the disc tissue during the advancing step.

11. The method of claim 1 wherein the applying step includes generating a voltage gradient between the active and return electrodes, the voltage gradient being sufficient to create an electric field that breaks down the tissue through molecular dissociation.

12. The method of claim 1 further comprising applying sufficient voltage to the active electrode in the presence of an electrically conductive fluid to vaporize at least a portion of the fluid between the active electrode and the disc tissue.

13. The method of claim 12 further comprising accelerating charged particles from the vaporized fluid to the disc tissue to cause dissociation of the molecular bonds within the disc tissue.

14. The method of claim 1 further comprising axially translating the active electrode to form a hole through at least a portion of the disc tissue.

15. The method of claim 1 further comprising transversely translating the active electrode relative to the disc tissue to form a channel along a surface of the disc.

16. The method of claim 1 wherein the space has a maximum lateral dimension less than about 2 mm.

17. The method of claim 1 wherein the space has a maximum lateral dimension less than about 1 mm.

18. The method of claim 1 wherein the positioning step comprises positioning a distal portion of a shaft of an electrosurgical instrument within the disc, wherein the active and return electrodes are both located on the distal portion of the shaft.

19. The method of claim 18 further comprising introducing at least the distal end portion of the shaft through a percutaneous penetration in the patient to the disc.

20. The method of claim 18 wherein the active electrode is positioned adjacent a target portion of the disc, the method further comprising locating the return electrode on the shaft such that, during the applying step, electric current flows from the active electrode away from the target portion of the disc to the return electrode, wherein the return electrode is axially spaced at least about 1.0 mm from the active electrode.

21. The method of claim 18 further comprising, after the applying step, deactivating the active electrode and applying a high frequency voltage difference between a second active electrode and one or more return electrodes on the instrument shaft.

22. The method of claim 21 wherein the instrument shaft comprises a second return electrode spaced proximally from the second active electrode, the method comprising, after the applying step, applying a high frequency voltage difference between the second active electrode and the first and second return electrodes.

23. The method of claim 18 further comprising, after the applying step, deactivating the active electrode and applying a high frequency voltage difference between the return electrode on the instrument shaft and a dispersive return electrode coupled to an external surface of the patient.

24. The method of claim 1 further comprising positioning the active and return electrodes within a nucleus of the disc and during the applying step, passing electric current between the active and return electrodes through naturally occuring conductive fluid within the nucleus.