Torsional dissection tip

• US 20050177184A1
• Filed: 02/05/2005
• Published: 08/11/2005
• Est. Priority Date: 02/09/2004
• Status: Abandoned Application

• Current Assignee: Stryker Corporation
• Original Assignee: Stryker Corporation
• Inventors: Easley, James C.
• Application Number:
  US11/051,796
• Publication Number:
  US 20050177184A1
• Time in Patent Office: Days
• US Class Current: 606/167
• CPC Class Codes: A61B 17/14 Surgical saws A61B17/1637 takes precedence; tooth saws A61C3/12 ; Accessories therefor
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61B 17/1671 for the spine
• CPC Class Codes: A61B 17/1679 for the ear
• CPC Class Codes: A61B 17/1688 for the sinus or nose
• CPC Class Codes: A61B 2017/320008 Scrapers
• CPC Class Codes: A61B 2017/32007 with suction or vacuum means
• CPC Class Codes: A61B 2017/320074 blade

Abstract

A torsional dissection tip and method of use comprising a longitudinal-torsional resonator having a cutting surface at a distal end with cutting teeth of a pitch optimized to the torsional or longitudinal displacement of the distal tip. Utilization of the present art torsional dissection tip allows a surgeon to easily remove hard tissues such as bone without moving the present art instrument to any site except that which is to be dissected.

Claims

1. A torsional dissection tip comprising:

a longitudinal-torsional resonator having a body, a first proximal end, and a second distal end, said second distal end capable of a torsional motion amplitude and/or a longitudinal motion amplitude when said first proximal end is excited by an ultrasonic generator producing a displacement, and

a cutting surface attached with said second distal end; and

a plurality of cutting teeth on said cutting surface; and

said cutting teeth having a pitch less than or equal to two times at least one of said torsional or longitudinal motion amplitudes.

2. The torsional dissection tip as set forth in claim 1 whereby said cutting surface further comprises:

a planar surface.

3. The torsional dissection tip as set forth in claim 1 further comprising:

a short arm attached between said second distal end and said cutting surface.

4. The torsional dissection tip as set forth in claim 3 whereby said cutting surface further comprises:

a planar surface having a first radius which substantially conforms to a second radius from a central axis of said longitudinal-torsional resonator to said cutting surface.

5. The torsional dissection tip as set forth in claim 1 further comprising:

a threaded portion at said first proximal end which connects with said ultrasonic generator; and

a tubular path extending from said threaded portion through said second distal end; and

an inhomogeneous cross sectional mass within the body of said longitudinal-torsional resonator, whereby a least a portion of said displacement from said ultrasonic generator is converted to a torsional displacement at said second distal end.

6. The torsional dissection tip as set forth in claim 5 whereby said inhomogeneous cross sectional mass comprises one or more grooves.

7. The torsional dissection tip as set forth in claim 5 further comprising:

a short arm attached between said second distal end and said cutting surface; and

a plurality of pyramidal forms having points forming said cutting teeth; and

said cutting surface having a planar surface having a first radius which substantially conforms to a second radius from a central axis of said longitudinal-torsional resonator to said cutting surface.

8. A torsional dissection tip comprising:

a longitudinal-torsional resonator having a first proximal end and a second distal end, said second distal end capable of a torsional motion amplitude and/or a longitudinal motion amplitude when said first proximal end is excited by an ultrasonic generator, and

a cutting surface attached with said second distal end; and

a plurality of cutting teeth on said cutting surface; and

said cutting teeth having a pitch less than or equal to at least one of said torsional or longitudinal motion amplitudes.

9. The torsional dissection tip as set forth in claim 8 whereby said cutting surface further comprises:

a planar surface.

10. The torsional dissection tip as set forth in claim 8 further comprising:

a short arm attached between said second distal end and said cutting surface.

11. The torsional dissection tip as set forth in claim 10 whereby said cutting surface further comprises:

a planar surface having a first radius which substantially conforms to a second radius from a central axis of said longitudinal-torsional resonator to said cutting surface.

12. The torsional dissection tip as set forth in claim 8 further comprising:

a threaded portion at said first proximal end which connects with said ultrasonic generator; and

a tubular path extending from said threaded portion through said second distal end; and

an inhomogeneous cross sectional mass within the body of said longitudinal-torsional resonator, whereby a least a portion of said displacement from said ultrasonic generator is converted to a torsional displacement at said second distal end.

13. The torsional dissection tip as set forth in claim 12 whereby said inhomogeneous cross sectional mass comprises one or more grooves.

14. The torsional dissection tip as set forth in claim 12 further comprising:

a short arm attached between said second distal end and said cutting surface; and

a plurality of pyramidal forms having points forming said cutting teeth; and

said cutting surface having a planar surface having a first radius which substantially conforms to a second radius from a central axis of said longitudinal-torsional resonator to said cutting surface.

15. A method of performing dissection of hard or dense biological tissues, the steps comprising:

forming a longitudinal-torsional resonator having a body, a first proximal end, and a second distal end;

ultrasonically exciting and displacing said first proximal end with an ultrasonic generator whereby said second distal end provides a torsional stroke and/or a longitudinal stroke; and

forming and attaching a cutting surface with said second distal end; and

forming a plurality of cutting teeth having a pitch less than or equal to at least one of said torsional or a longitudinal strokes on said cutting surface; and

contacting said cutting surface onto a hard or dense biological tissue and thereby removing said tissue without requiring constant motion of said second distal end.

16. The method of performing dissection of hard or dense biological tissues as set forth in claim 15, the steps further comprising:

placing and connecting a short arm between said second distal end and said cutting surface.

17. The method of performing dissection of hard or dense biological tissues as set forth in claim 16, the steps further comprising:

forming one or more grooves within said body whereby said second distal end torsional stroke is maximized.

18. The method of performing dissection of hard or dense biological tissues as set forth in claim 17, the steps further comprising:

forming said cutting teeth from a plurality of pyramidal forms.