Electrode assembly for rf energy enabled tissue debridement device

Patent metadata

Field	Value
Publication number	US-2016235474-A1
Application number	US-201615046869-A
Country	US
Kind code	A1
Filing date	Feb 18, 2016
Priority date	Feb 18, 2015
Publication date	Aug 18, 2016
Grant date	—

Abstract

A bipolar electrosurgical device is disclosed that operates in a mechanical cutting mode and a hemostasis mode. The device includes a housing and a blade assembly extending from the housing. The blade assembly forms a cutting tip and cutting window at a distal end region to provide mechanical cutting of tissue and first and second electrode assemblies to provide electrical energy to tissue. The first electrode assembly includes an outer shaft defining a first electrode surface and the second electrode assembly includes an electrode body extending along and electrically isolated from an outer shaft and defining a U-shape in cross section.

First claim

What is claimed is:

1 . A blade assembly extending from a proximal region to a distal region, comprising:
an outer shaft assembly defining a lumen extending along a central axis, an outer circumference, a proximal end and a distal end opposite the proximal end, wherein the distal end defines a cutting window in the outer shaft assembly and a first electrode surface; an inner shaft assembly rotatably disposed within the lumen of the outer shaft assembly about the central axis, the inner shaft assembly defining a distal portion, the distal portion further including a cutting tip; an electrode body extending along the outer circumference and electrically isolated from the outer shaft, the electrode body defining a U-shape in cross section with respect to a plane that is perpendicular to the central axis and a second electrode surface spaced apart from the first electrode surface; a hub rotatably supporting the outer shaft and the electrode body, wherein upon rotation of the hub about the central axis, the outer shaft and the electrode body rotate about the central axis; a rotary electrical connection assembly comprising an outer connector and an inner connector rotatably disposed within the outer connector, the inner connector electrically connected to the electrode body; an irrigation channel fluidly coupled with the hub and configured to deliver fluid from the proximal region to the distal region; and wherein each of the outer connector, the inner connector and the electrode body are formed of a conductive material and extend a respective length in a direction parallel to the central axis, and further wherein, when viewed in cross section along an entirety of the respective length and with respect to the plane that is perpendicular to the central axis, each define a maximum distance from the central axis that includes conductive material such that, for a circle having an origin at the central axis and a circumference at the maximum distance, there exists at least one sector of the circle free of conductive material.

2 . The blade assembly of claim 1 , wherein the body includes an inner surface facing the outer shaft and an outer surface opposite the inner surface and wherein the blade assembly further includes an insulating body covering the outer surface of the electrode body and the outer circumference of the outer shaft.

3 . The blade assembly of claim 2 , wherein the insulating body is heat shrink tubing.

4 . The blade assembly of claim 1 , further comprising wherein the irrigation channel is positioned between the outer circumference of the outer shaft and the electrode body.

5 . The blade assembly of claim 4 , wherein the electrode body further defines a distal cup fluidly coupled with the irrigation channel, the distal cup directing fluid from the irrigation channel between the first electrode surface and the second electrode surface.

6 . The blade assembly of claim 1 , wherein the electrode body terminates at a position with respect to the hub that is closer to the distal end than the proximal end.

7 . The blade assembly of claim 1 , wherein the U-shape defines opposed ends spaced apart around the outer circumference approximately 180 degrees.

8 . The blade assembly of claim 1 , wherein the U-shape defines opposed ends spaced apart around the outer circumference less than 180 degrees.

9 . The blade assembly of claim 1 , wherein the U-shape defines opposed ends spaced apart around the outer circumference greater than 180 degrees.

10 . The blade assembly of claim 1 , further comprising an insulating coating positioned between the outer circumference of the outer shaft and the electrode body.

11 . The blade assembly of claim 1 , wherein the electrode body extends around the outer shaft to cover a distal-most tip of the outer shaft.

Assignees

• Medtronic Xomed Inc

Inventors

• Prisco John R
• Detmers Eric P
• Li Wenjeng
• Little David J
• Richart Patrick
• Valdez Jose

Classifications

• A61B18/1445 Primary

  at the distal end of a shaft, e.g. forceps or scissors at the end of a rigid rod · CPC title

• A61B2018/00601

  Cutting · CPC title

• A61B18/148

  having a short, rigid shaft for accessing the inner body transcutaneously, e.g. for neurosurgery or arthroscopy · CPC title

• A61B18/1485 Primary

  having a short rigid shaft for accessing the inner body through natural openings · CPC title

• A61B17/32002

  with continuously rotating, oscillating or reciprocating cutting instruments · CPC title