System and methods for electrosurgical tissue contraction within the spine

• US 6,620,155 B2
• Filed: 02/20/1998
• Issued: 09/16/2003
• Est. Priority Date: 07/16/1996
• Status: Expired due to Term

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Eggers, Philip E., Thapliyal, Hira V., Underwood, Ronald A., Davison, Terry S.
• Primary Examiner(s): COHEN, LEE S
• Application Number:
  US09/026,698
• Publication Number:
  US 20020151885A1
• Time in Patent Office: 2,034 Days
• Field of Search: 606/32, 606/34, 606/41, 606/49, 606/50, 607/99, 607/105, 607/113, 128/898, 604/114, 604/35
• US Class Current: 606/32
• CPC Class Codes: A61B 18/12 by passing a current through the tissue to be heated, e.g. high-frequency current
• CPC Class Codes: A61B 18/1206 Generators therefor
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• CPC Class Codes: A61B 18/1402 Probes for open surgery
• 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 2017/00097 one of the thermometric elements being an electrode or the heating element
• 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 2017/00292 mounted on or guided by flexible, e.g. catheter-like, means
• CPC Class Codes: A61B 2017/003 Steerable
• CPC Class Codes: A61B 2017/22001 Angioplasty, e.g. PCTA
• CPC Class Codes: A61B 2017/22038 with a guide wire
• 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 2018/00196 : reciprocating lengthwise
• 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 2018/00505 : Urinary tract
• 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 2018/00642 : with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/0066 : without feedback, i.e. open loop control
• 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 2018/00761 : Duration
• CPC Class Codes: A61B 2018/00791 : Temperature
• CPC Class Codes: A61B 2018/00797 : measured by multiple temperature sensors
• CPC Class Codes: A61B 2018/00821 : measured by a thermocouple
• CPC Class Codes: A61B 2018/00827 : Current
• CPC Class Codes: A61B 2018/00875 : Resistance or impedance
• CPC Class Codes: A61B 2018/00886 : Duration
• 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 2018/1467 : 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 2018/1497 : Electrodes covering only part of the probe circumference
• CPC Class Codes: A61B 2018/162 : located on the probe body
• CPC Class Codes: A61B 2018/165 : Multiple indifferent electrodes
• CPC Class Codes: A61B 2090/378 : using ultrasound
• CPC Class Codes: A61B 2218/002 : Irrigation
• CPC Class Codes: A61B 2218/007 : Aspiration
• CPC Class Codes: A61F 2/2493 : Transmyocardial revascularisation [TMR] devices
• CPC Class Codes: A61M 25/0133 : Tip steering devices
• CPC Class Codes: A61M 25/0147 : with movable mechanical means, e.g. pull wires
• CPC Class Codes: A61M 25/0158 : with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials

Abstract

The present invention provides systems and methods for selectively applying electrical energy to a target location within a patient'"'"'s body, particularly including tissue in the spine. The present invention applies high frequency (RF) electrical energy to one or more electrode terminals in the presence of electrically conductive fluid to contract collagen fibers within the tissue structures. In one aspect of the invention, a system and method is provided for treating herniated or swollen discs within a patient'"'"'s spine by applying sufficient electrical energy to the disc tissue to contract or shrink the collagen fibers within the nucleus pulposis. This causes the pulposis to shrink and withdraw from its impingement on the spinal nerve.

Claims

1. A method for treating a target tissue within an inter-vertebral disc of a patient'"'"'s spine using an electrosurgical probe, the method comprising:

introducing a distal end of a shaft of the probe into the disc, the probe including an electrode terminal and a return electrode, the electrode terminal and the return electrode disposed at the distal end of the shaft;

positioning the electrode terminal and the return electrode within a nucleus pulposus of the disc such that the electrode terminal is not in contact with, and spaced from, an annulus fibrosus of the disc; and

applying a high frequency voltage between the electrode terminal and the return electrode, the voltage being sufficient to contract collagen fibers within the nucleus pulposus.

2. The method of claim 1 wherein said introducing step comprises advancing the distal end of the shaft through the annulus fibrosus into the nucleus pulposus.

3. The method of claim 1 wherein said introducing step comprises advancing the distal end of the shaft through an opening in the annulus fibrosus, the opening having a diameter less than 2 mm.

4. The method of claim 1 wherein said introducing step comprises advancing the distal end of the shaft through an opening in the annulus fibrosus, the opening having a diameter less than 1 mm.

5. The method of claim 1 wherein the distal end of the shaft is introduced anteriorly through the patient to the spine.

6. The method of claim 1 wherein the nucleus pulposus includes a non-extruded portion and an extruded portion, the extruded portion extending through the annulus fibrosus, and wherein said positioning step comprises positioning the electrode terminal within the non-extruded portion of the nucleus pulposus.

7. The method of claim 1 further comprising:

delivering an electrically conductive fluid to at least one of the electrode terminal and the nucleus pulposus.

8. The method of claim 7 wherein the electrically conductive fluid completes a current flow path between the electrode terminal and the return electrode.

9. The method of claim 1 further comprising:

withdrawing the electrode terminal from the nucleus pulposus and from the annulus fibrosus; and

applying sufficient high frequency voltage to the electrode terminal during the withdrawing step to contract collagen fibers within the annulus fibrosus.

10. A method for treating a target tissue within an inter-vertebral disc of a patient, the inter-vertebral disc having an annulus fibrosus and a nucleus pulposus, and the method comprising:

positioning a shaft distal end of an electrosurgical probe within the nucleus pulposus, the probe including an electrode terminal and a return electrode, the electrode terminal and the return electrode disposed at the shaft distal end, and wherein the electrode terminal is not in contact with, and spaced from, the annulus fibrosus; and

applying a high frequency voltage between the electrode terminal and the return electrode, the voltage being sufficient to contract collagen fibers within the nucleus pulposus.

11. The method of claim 10 further comprising delivering an electrically conductive fluid between the electrode terminal and the return electrode, wherein the electrically conductive fluid completes a current flow path between the electrode terminal and the return electrode.

12. The method of claim 10, wherein said positioning step comprises locating the shaft distal end within the disc such that the electrode terminal and the return electrode are surrounded by the target tissue, wherein the target tissue is nucleus pulposus tissue.

13. A method of contracting a target tissue within a nucleus pulposus of an inter-vertebral disc of a patient using an electrosurgical probe, the method comprising:

a) advancing the probe towards the disc, wherein the probe includes a shaft having a shaft distal end, an electrode terminal and a return electrode, the electrode terminal and the return electrode disposed on the shaft distal end;

b) positioning the shaft distal end of the probe within the nucleus pulposus of the disc, such that both the electrode terminal and the return electrode are located within the nucleus pulposus and spaced away from the annulus; and

c) while the probe is positioned according to said step b), applying a high frequency voltage between the electrode terminal and the return electrode, whereby the target tissue within the nucleus pulposus undergoes contraction.

14. The method of claim 13 further comprising:

d) prior to or during said step c), delivering an electrically conductive fluid to the shaft distal end, such that the electrically conductive fluid provides a current flow path between the electrode terminal and the return electrode.

15. The method of claim 13, further comprising:

e) after said step d), heating a quantity of the electrically conductive fluid via application of the high frequency voltage of said step c) to provide a heated fluid adjacent to the target tissue; and

f) heating the target tissue via the heated fluid provided in said step e).

16. The method of claim 13 wherein the shaft distal end is positioned within the nucleus pulposus by translating the probe axially.

17. The method of claim 13 wherein the shaft distal end is adapted for penetrating an annulus fibrosus of the disc.

18. The method of claim 13 wherein the shaft remains linear during said steps a), b), and c).

19. The method of claim 13 wherein said step b) comprises positioning the shaft distal end within the nucleus pulposus such that both the electrode terminal and the return electrode avoid contact with the annulus fibrosus.

20. The method of claim 13 wherein said step c) causes the target tissue to be heated to a temperature in the range of from about 45°

C. to 90°

C.

21. The method of claim 13 wherein said step c) causes the target tissue to be heated to a temperature in the range of from about 60°

C. to 70°

C.