Electrosurgical system for treating the spine

• US 6,575,968 B1
• Filed: 05/16/2000
• Issued: 06/10/2003
• Est. Priority Date: 01/07/1992
• Status: Expired due to Fees

• Current Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Original Assignee: ArthroCare Corporation (Smith & Nephew PLC)
• Inventors: Eggers, Philip E., Thapliyal, Hira V.
• Primary Examiner(s): PEFFLEY, MICHAEL F
• Application Number:
  US09/571,343
• Time in Patent Office: 1,120 Days
• Field of Search: 606/41, 606/42, 606/45-50, 607/101-105, 604/114
• US Class Current: 606/41
• 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

An electrosurgical ablation probe is provided having a shaft with a proximal end portion and a tongue-shaped distal end portion sized to fit within confined (e.g., narrow) spaces within the patient'"'"'s body, such as the spaces around the articular cartilage between the femur and tibia and the spaces between adjacent vertebrae in the patient'"'"'s spine. The probe includes at least one active electrode integral with or coupled to the tongue-shaped distal end portion and a connector on the proximal end portion for coupling the active electrode to an electrosurgical generator. The tongue-shaped distal end portion is substantially planar, and it offers a low profile, to allow access to confined spaces without risking iatrogenic injury to surrounding tissue, such as articular cartilage.

Claims

1. An electrosurgical probe for treating tissue within a patient'"'"'s spine comprising:

a shaft having a proximal end portion and a distal end portion sized to fit between adjacent intervertebral disks in the patient'"'"'s spine;

an electrode terminal extending away from the distal end portion of the shaft, the electrode terminal comprising at least a first electrode having a planar cross section where a width of the first electrode is greater than a thickness of the first electrode, the first electrode having an active surface and a non-active surface, where the non-active surface is covered with an insulating material such that current is prevented from flowing to or from the non-active surface; and

a connector within the shaft for coupling the electrode terminal to a high frequency voltage source.

2. The probe of claim 1 further comprising a return electrode on the shaft space from the electrode terminal.

3. The probe of claim 1 wherein the thickness of the first electrode is less than 2 mm.

4. The probe of claim 3 wherein the thickness of the first electrode is less than 1 mm.

5. The probe of claim 1 further comprising an electrically insulating member positioned between the electrode terminal and the return electrode.

6. The probe of claim 1 wherein the electrode terminal comprises at least one or more additional electrodes.

7. The probe of claim 1 wherein, at least two adjacent electrodes are connected to opposite polarities of the high frequency voltage source.

8. The probe of claim 7 wherein each electrode is connected to the opposite polarity of the adjacent electrode.

9. The probe of claim 1 wherein the first electrode has a cross section selected from the profile consisting of a semi-circle, a square, a d-shape, a cross, a circle, and a circular shape with protrusions extending therefrom.

10. The probe of claim 1 wherein the non-active surface of the first electrode has a substantially smooth, atraumatic surface to minimize damage to tissue.

11. An electrosurgical apparatus for treating tissue within a patient'"'"'s spine comprising:

a shaft having a proximal end portion and a distal end portion sized to fit between adjacent intervertebral disks in the patient'"'"'s spine;

an electrode terminal extending away from the distal end portion of the shaft, the electrode terminal comprising at least a first electrode having a planar cross section where a width of the first electrode is greater than a thickness of the first electrode, the first electrode having an active surface and a non-active surface, where the non-active surface is covered with an insulating material such that current is prevented from flowing to or from the non-active surface;

a return electrode; and

means for applying a high frequency voltage difference between the electrode terminal and the return electrode in the presence of electrically conductive fluid to treat target tissue between the intervertebral disks.

12. An electrosurgical apparatus for treating tissue within a patients spine comprising:

a shaft having a proximal end portion, a distal end portion sized to fit between adjacent intervertebral disks in the patient'"'"'s spine and an electrode terminal extending away from the distal end portion of the shaft, the electrode terminal comprising at least a first electrode having a planar cross section where a width of the first electrode is greater than a thickness of the first electrode, the first electrode having an active surface and a non-active surface, where the non-active surface is covered with an insulating material such that current is prevented from flowing to or from the non-active surface;

an electrically conductive fluid source;

a high frequency voltage source;

a connector within the shaft coupling the electrode terminal to the high frequency voltage source; and

a fluid delivery element coupled to the electrically conductive fluid source for delivering electrically conductive fluid to a target site such that the conductive fluid substantially surrounds an exposed portion of the electrode terminal.

13. An electrosurgical probe for applying electrical energy to a target site within a confined spaced in a patient'"'"'s body, the instrument comprising:

a shaft having a proximal end portion, a distal end portion extending from the shaft, the distal end portion having an axial length, a thickness substantially less than said length and a width substantially larger than said thickness to form a substantially planar body having an active side and a non-active side opposing the active side sized to fit within a relatively narrow space within the patient'"'"'s body ,the distal end portion having an active side and a substantially planar non-active side opposing the active side;

a connector disposed near the proximal end portion of the shaft for electrically coupling the electrode to a high frequency voltage source; and

a plurality of active electrode disposed on the active side of the distal end portion of the shaft and being insulated from the non-active side, wherein at least one pair of adjacent electrodes are connected to opposite polarities of the high frequency voltage source, whereby one of the pair of electrodes functions as a return electrode.

14. The probe of claim 13 wherein each electrode is connected to the opposite polarity of the adjacent electrode.

15. The probe of claim 13 wherein the distal end portion includes a substantially planar support member underlying and insulated from the active electrode.

16. The probe of claim 15 wherein the support member has a substantially smooth, atraumatic surface opposite the active electrode to minimize damage to tissue.

17. The probe of claim 13 wherein the active electrode comprises an elongate body having a distal active portion with a surface geometry configured to promote substantially high electric field intensities between the active portion and the target site when a high frequency voltage is applied to the electrode.

18. The probe of claim 17 wherein the active portion of the active electrode defines a semi-circular transverse cross-sectional shape with first and second ends and an inner slot therebetween, the first and second ends each having a pair of edges for promoting localized high electric field intensities near the edges.

19. The probe of claim 18 wherein the distal end portion of the shaft includes a support member and an insulating layer disposed between the support member and the active electrode, the first and second ends of the active portion facing away from the insulating layer.

20. The probe of claim 19 wherein the first and second ends of the active portion form a planar surface that is substantially parallel to the support member.

21. The probe of claim 17 wherein the active portion of the active electrode is positioned in close proximity to the target site in the presence of electrically conducting liquid, the surface geometry of the active portion configured to promote high electric field intensities sufficient to vaporize the electrically conducting liquid in a thin layer over at least a portion of the electrode surface and to induce the discharge of energy from the vapor layer.

22. The probe of claim 13 wherein the distal end portion of the shaft has a length less than about 10 mm and a width less than about 10 mm.

23. The probe of claim 13 further comprising an array of electrically isolated active electrodes, each having a semi-circular cross-section with first and second ends and an inner slot therebetween, the first and second ends each having a pair of edges for promoting localized high electric field intensities near the edges.

24. The probe of claim 23 wherein the active electrodes are spaced from each other by a distance of about 5 to 100 mils.