Ultrasonic surgical instrument blades

• US 20090143795A1
• Filed: 11/30/2007
• Published: 06/04/2009
• Est. Priority Date: 11/30/2007
• Status: Active Grant

• Current Assignee: Cilag Gmbh International (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Robertson, Galen C.
• Granted Patent: US 8,057,498 B2
• Time in Patent Office: Days
• US Class Current: 606/169
• CPC Class Codes: A61B 17/320068 using mechanical vibrations, e.g. ultrasonic A61B17/22012 takes precedence; dental tooth drilling devices operated by vibration A61C3/03; removing intra-ocular material using mechanical vibrations A61F9/00745
• CPC Class Codes: A61B 17/320092 with additional movable means for clamping or cutting tissue, e.g. with a pivoting jaw
• CPC Class Codes: A61B 17/3205 Excision instruments
• CPC Class Codes: A61B 2017/00973 pedal-operated
• CPC Class Codes: A61B 2017/320069 for ablating tissue
• CPC Class Codes: A61B 2017/320071 with articulating means for working tip
• CPC Class Codes: A61B 2017/320072 Working tips with special features, e.g. extending parts
• CPC Class Codes: A61B 2017/320074 blade
• CPC Class Codes: A61B 2017/320082 for incising tissue
• CPC Class Codes: A61B 2017/320084 Irrigation sleeves
• CPC Class Codes: A61B 2017/320088 with acoustic insulation, e.g. elements for damping vibrations between horn and surrounding sheath
• CPC Class Codes: A61B 2017/320089 node location
• CPC Class Codes: A61B 2017/320094 additional movable means performing clamping operation
• CPC Class Codes: Y10S 83/956 Ultrasonic

Abstract

An ultrasonic surgical instrument including an ultrasonically actuated blade or end effector having a treatment portion. The blade can define a central axis and at least one axis which is transverse to the central axis, wherein the transverse axis can lie within a plane which is perpendicular, or normal, to the longitudinal axis and can define a cross-section of the treatment portion. Such a cross-section can include a central portion and a step extending from the central portion, wherein the central portion can comprise a width, and wherein the step can comprise a cutting edge. In at least one embodiment, the cutting edge can be defined by first and second surfaces which define an angle therebetween. In various embodiments, the position of the cutting edge and/or the angle between the cutting edge surfaces can be selected in order to balance the blade with respect to the transverse axis.

Claims

1. A surgical blade for a surgical instrument, the surgical instrument having a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency, the surgical blade comprising:

a body portion comprising a first side, a second side, and a width defined between said first and second sides;

a step portion extending from said body portion, wherein said step portion comprises a first surface, a second surface, and a cutting edge situated intermediate said first and second surfaces, wherein said second surface extends between a first plane including said cutting edge and a second plane which is parallel to said first plane, wherein said first surface is not parallel to said second surface, wherein said first and second surfaces are oriented such that there is an angle defined therebetween, wherein said blade is configured such that the relationship of;

$\frac{x^2}{2}*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}+\frac{\left(w-x\right)}{2}<br><br>\left(x*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}-s\right)-{\left(\frac{w}{2}\right)}^2<br><br>{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}$

is substantially equal to zero;

wherein w is said width of said body portion;

wherein s is the distance between said first plane and said second plane;

wherein α

is said angle defined between said first and second surfaces of said step portion; and

wherein x is the distance between said second side of said body portion and said cutting edge.

2. The surgical blade of claim 1, wherein said body portion includes a centerline, wherein said step portion includes a center of gravity positioned along said centerline, and wherein said cutting edge is not positioned along said centerline.

3. The surgical blade of claim 2, wherein said second surface is substantially parallel to said centerline.

4. The surgical blade of claim 1, wherein said body portion includes a centerline, wherein said step portion includes a center of gravity positioned along said centerline, and wherein said step portion is asymmetric with respect to said centerline.

5. The surgical blade of claim 1, wherein said relationship is equal to zero.

6. A surgical blade for a surgical instrument, the surgical instrument having a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency, the surgical blade comprising:

a body portion comprising a first side, a second side, and a width (w) defined between said first and second sides;

a step portion extending from said body portion, wherein said step portion comprises a first surface, a second surface, and a cutting edge situated intermediate said first and second surfaces, wherein said second surface extends between a first plane including said cutting edge and a second plane which is parallel to said first plane, wherein said first plane and said second plane are separated by a distance s, wherein said first surface is not parallel to said second surface, wherein said first and second surfaces are oriented such that there is an angle (α

) defined therebetween, and wherein a second distance (x) is defined between said second side of said body portion and said cutting edge.

7. The surgical blade of claim 6, wherein said blade is configured such that, for any given values of s and w, the relationship of:

A*x²*tan<sup>−

1</sup> α

+B*x*tan<sup>−

1</sup> α

+C*tan<sup>−

1</sup> α

+D*x+E

is substantially equal to zero, and wherein A, B, C, D, and E are constants.

8. The surgical blade of claim 6, wherein said blade is configured such that, for any given values of s and α

, the relationship of;

A*x²+B*x+C*x*w+D*w+E*w²+F

is substantially equal to zero, and wherein A, B, C, D, E, and F are constants.

9. The surgical blade of claim 6, wherein said blade is configured such that, for any given values of w and α

, the relationship of;

A*x²+B*x+C*x*s+D*s+E

is substantially equal to zero, and wherein A, B, C, D, and E are constants.

10. A surgical blade for a surgical instrument, the surgical instrument having a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency, the surgical blade comprising:

a distal end;

a proximal end; and

a cross-section situated intermediate said distal end and said proximal end, wherein said cross-section is defined by a plane which is perpendicular to the longitudinal axis, wherein said cross-section is further defined by a centerline which lies in the plane, and wherein said cross-section comprises;

a center portion; and

a cutting portion extending from said center portion, wherein said cutting portion comprises a center of gravity which is positioned along said centerline, and wherein said cutting portion further comprises a cutting edge which is not positioned along said centerline.

11. The surgical blade of claim 10, wherein said cutting portion comprises a first surface and a second surface, wherein said cutting edge is situated intermediate said first and second surfaces, wherein said first surface is not parallel to said second surface, wherein said first and second surfaces are oriented such that there is an angle defined therebetween.

12. The surgical blade of claim 11, wherein said center portion includes a first side, a second side, and a width defined between said first and second sides, wherein said second surface of said cutting portion extends between a first plane including said cutting edge and a second plane which is parallel to said first plane, wherein said blade is configured such that the relationship of:

$\frac{x^2}{2}*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}+\frac{\left(w-x\right)}{2}<br><br>\left(x*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}-s\right)-{\left(\frac{w}{2}\right)}^2<br><br>{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}$

is substantially equal to zero;

wherein w is said width of said center portion;

wherein s is the distance between said first plane and said second plane;

wherein α

is said angle defined between said first and second surfaces of said cutting portion; and

wherein x is the distance between said second side of said center portion and said cutting edge.

13. The surgical blade of claim 12, wherein said relationship is equal to zero.

14. A method of balancing an ultrasonic instrument having an ultrasonically actuated blade, wherein the blade comprises a body portion and a step portion extending from the body portion, wherein the body portion comprises a first side, a second side, and a width defined between the first and second sides, wherein the step portion includes a first surface, a second surface, and a cutting edge situated intermediate the first and second surfaces, wherein the second surface extends between a first plane including the cutting edge and a second plane which is parallel to the first plane, wherein the first and second surfaces are not parallel and are oriented such that there is an angle defined therebetween, the method comprising the steps of:

configuring at least a portion of the blade such that the relationship of;

$\frac{x^2}{2}*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}+\frac{\left(w-x\right)}{2}<br><br>\left(x*{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}-s\right)-{\left(\frac{w}{2}\right)}^2<br><br>{\tan }^{-1}<br><br>\mathrm{\alpha <br><br>}$

is substantially equal to zero;

wherein w is said width of the body portion;

wherein s is the distance between the first plane and the second plane;

wherein α

is said angle defined between the first and second surfaces of the step portion; and

wherein x is the distance between the second side of the body portion and the cutting edge.

15. The method of claim 14, wherein said configuring step comprises the steps of:

selecting values for w, s, and α

such that the blade is configured to transect tissue; and

solving said relationship for x.

16. The method of claim 14, wherein said configuring step comprises the steps of:

selecting values for w, x, and a such that the blade is configured to transect tissue; and

solving said relationship for s.

17. The method of claim 14, wherein said relationship is equal to zero.

18. A surgical blade for a surgical instrument, the surgical instrument having a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency, the surgical blade comprising:

a distal end;

a proximal end; and

a cross-section situated intermediate said distal end and said proximal end, wherein said cross-section is defined by a plane which is perpendicular to the longitudinal axis, wherein the plane is at least partially defined by a transverse axis which is perpendicular to the longitudinal axis, and wherein the cross-section comprises;

a body portion having a first mass (M_B1) positioned on a first side of said transverse axis and a second mass (M_B2) positioned on a second side of said transverse axis; and

a step portion having a first mass (M_S1) positioned on said first side and a second mass (M_S2) positioned on said second side, wherein M_B1+M_S1 is substantially equal to M_B2+M_S2, wherein said step portion further includes a cutting edge, and wherein said cutting edge is not positioned along said transverse axis.

19. The surgical blade of claim 18, wherein M_B1+M_S1 is equal to M_B2+M_S2.