Arthroscopic shaver incorporating electrocautery

• US 5,810,809 A
• Filed: 01/13/1997
• Issued: 09/22/1998
• Est. Priority Date: 01/13/1997
• Status: Expired due to Fees

• Current Assignee: Enhanced Orthopaedic Technologies, Inc.
• Original Assignee: Enhanced Orthopaedic Technologies, Inc.
• Inventors: Rydell, Mark A.
• Primary Examiner(s): PEFFLEY, MICHAEL F
• Application Number:
  US08/782,719
• Time in Patent Office: 617 Days
• Field of Search: 606/1, 606/41, 606/42, 606/45-50, 606/170, 606/171, 606/180, 604/22
• US Class Current: 606/49
• CPC Class Codes: A61B 17/32002 with continuously rotating, oscillating or reciprocating cutting instruments
• CPC Class Codes: A61B 18/14 Probes or electrodes therefor
• 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 2217/005 with suction drainage system
• CPC Class Codes: A61B 2217/007 with irrigation system

Abstract

An arthroscopy instrument for debriding tissue also includes an electrocautery electrode for effecting hemostasis in the surgical site. The drive motor for the debriding instrument is placed remotely from the instrument'"'"'s handle and provision is made for electrically insulating the handle from the drive motor and associated power supply even though the arthroscopic surgery is taking place under saline.

Claims

1. In an arthroscopic shaver of the type including a handle for supporting an outer, stationary, elongated, tubular metal cutting blade and an inner, rotatable, elongated, tubular, metal cutting blade, where the outer tubular metal blade includes a window opening proximate a distal end thereof, the handle including an aspiration lumen adapted to be connected to a vacuum source and in fluid communication with a lumen of the inner tubular cutting blade, and motor means for rotating the inner tubular metal cutting blade, the improvement comprising:

(a) means for defining an electrode surface proximate the distal end of the outer tubular cutting blade;

(b) means for applying an electrical cautery voltage to said electrode surface; and

(c) flexible drive shaft means for coupling the motor means to the rotatable cutting blade and for electrically isolating the electrocautery voltage from the motor means.

2. The arthroscopic shaver as in claim 1 wherein the means for defining the electrode surface comprises:

(a) an elongated, tubular sheath disposed coaxially relative to the outer tubular metal cutting blade, the sheath covering all but a predetermined area proximate the distal end of the outer tubular cutting blade.

3. The arthroscopic shaver as in claim 1 wherein the motor means for rotating the inner tubular metal cutting blade is located remote from the handle.

4. The arthroscopic shaver as in claim 3 wherein the handle includes a rigid rotatable drive shaft journaled therein, one end of the rigid drive shaft adapted to engage a proximal end of the inner tubular metal cutting blade, the other end of the rigid drive shaft being coupled to the motor means by said flexible drive shaft means.

5. The arthroscopic shaver as in claim 4 wherein the handle is an insulating plastic material.

6. The arthroscopic shaver as in claim 5 wherein said other end of the drive shaft is connected to the flexible drive shaft means by an insulating coupler.

7. The arthroscopic shaver as in claim 2 and further including at least one control switch mounted on the handle for selectively connecting the electrode surface to a source of electrocautery voltage.

8. The arthroscopic shaver as in claim 1 wherein the means for defining an electrode surface proximate the distal end of the outer tubular cutting blade comprises a sheath member having a proximal and a distal end and first and second lumens extending therebetween, the first lumen for containing the outer tubular metal cutting blade and the second lumen for containing an elongated wire conductor with a distal end portion of the wire conductor extendable beyond the distal end of the sheath.

9. The arthroscopic shaver as in claim 8 wherein all but a distal end portion of the elongated wire conductor is covered with an electrically insulating material.

10. The arthroscopic shaver as in claim 8 and further including a head member affixed to the proximal end of the sheath, the head member being keyed to the handle and including a thumb slide member thereon, the thumb slide member being coupled to the elongated wire conductor for advancing and retracting the distal end portion of the wire conductor relative to the distal end of the sheath.

11. The arthroscopic shaver as in claim 10 wherein the head member includes a switch housing containing a switch contact and the thumb slide member includes a push-button for actuating the switch contacts.

12. The arthroscopic shaver as in claim 10 wherein the means for applying an electrocautery voltage to the electrode surface comprises an elongated multiconductor cord having a first terminal for mating with an electrosurgical generator and a second terminal connected to the elongated wire conductor.

13. An arthroscopic shaver incorporating an electrocautery electrode comprising:

(a) a rigid, elongated, tubular handle member having a plurality of lumens extending longitudinally therein;

(b) a drive shaft journaled by bearing means within a first of said plurality of lumens;

(c) a cutter assembly comprising

(i) an outer tube having a proximal end, a distal end and a lumen extending therebetween, the outer tube having an opening in a side wall thereof proximal said distal end of said outer tube leading to the lumen of the outer tube and a first hub affixed to the proximal end of the outer tube,

(ii) a generally rigid inner tube coaxially disposed and rotatable within the lumen of the outer tube, the inner tube having a cutting element formed thereon proximal a distal end and cooperating with the opening in the side wall of the outer tube, the inner tube including a second hub affixed to a proximate end thereof and journaled to rotate within the first hub on the outer tube;

(d) coupling means on the drive shaft for mating with the second hub when said cutter assembly is inserted into said first of said plurality of lumens;

(e) a tubular insulative sheath coaxially disposed about the outer tube, and having a length dimension less than that of the outer tube to leave the opening unobstructed;

(f) means for applying an electrocautery voltage to the outer tube; and

(g) motor means located remote from the tubular handle and coupled to the drive shaft for driving the drive shaft, the motor means being electrically isolated from the electrocautery voltage.

14. The arthroscopic shaver as in claim 13 and further including means coupled to a second of said plurality of lumens in the handle for applying a vacuum to a lumen of the inner tube for drawing tissue to be cut into the opening of the outer tube.

15. In an arthroscopic shaver of the type including a handle for supporting an outer, stationary, elongated, tubular metal cutting blade and an inner, rotatable, elongated, tubular, metal cutting blade, where the outer tubular metal blade includes a window opening proximate a distal end thereof, the handle including an aspiration lumen adapted to be connected to a vacuum source and in fluid communication with a lumen of the inner tubular cutting blade, and motor means for rotating the inner tubular metal cutting blade, the improvement comprising:

(a) means for defining an electrode surface proximate the distal end of the outer tubular cutting blade, that comprises a sheath member having a proximal and a distal end and first and second lumens extending therebetween, the first lumen for containing the outer tubular metal cutting blade and the second lumen for containing an elongated wire conductor with a distal end portion of the wire conductor extendable beyond the distal end of the sheath; and

(b) means for applying an electrical cautery voltage to said elongated wire conductor.

16. The arthroscopic shaver as in claim 15 wherein all but a distal end portion of the elongated wire conductor is covered with an electrically insulating material.

17. The arthroscopic shaver as in claim 15 and further including a head member affixed to the proximal end of the sheath, the head member being keyed to the handle and including a thumb slide member thereon, the thumb slide member being coupled to the elongated wire conductor for advancing and retracting the distal end portion of the wire conductor relative to the distal end of the sheath.

18. The arthroscopic shaver as in claim 17 wherein the head member includes a switch housing containing a switch contact and the thumb slide member includes a push-button for actuating the switch contacts.

19. The arthroscopic shaver as in claim 17 wherein the means for applying an electrocautery voltage to the electrode surface comprises an elongated multi-conductor cord having a first terminal for mating with an electrosurgical generator and a second terminal connected to the elongated wire conductor.