Blades with functional balance asymmetries for use with ultrasonic surgical instruments

• US 6,773,444 B2
• Filed: 09/20/2001
• Issued: 08/10/2004
• Est. Priority Date: 10/05/1999
• Status: Expired due to Term

• Current Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Original Assignee: Ethicon Endo-Surgery, Inc. (Johnson & Johnson)
• Inventors: Messerly, Jeffrey D.
• Primary Examiner(s): Woo, Julian W.
• Application Number:
  US09/957,174
• Publication Number:
  US 20020128645A1
• Time in Patent Office: 1,055 Days
• Field of Search: 606/169, 606/170, 606/34, 606/37, 606/39, 606/40, 606/205, 606/207, 600/437, 600/439, 600/471
• US Class Current: 606/169
• CPC Class Codes: A61B 17/2816 Pivots
• 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 2017/2825 Inserts of different material in jaws
• CPC Class Codes: A61B 2017/2929 with a head rotatable about the longitudinal axis of the shaft
• CPC Class Codes: A61B 2017/320075 single edge blade, e.g. for cutting
• CPC Class Codes: A61B 2017/320093 additional movable means performing cutting operation
• CPC Class Codes: A61B 2017/320094 additional movable means performing clamping operation
• CPC Class Codes: A61B 2017/320095 with sealing or cauterizing means

Abstract

Disclosed is an ultrasonic surgical instrument that combines end-effector geometry to best affect the multiple functions of a shears-type configuration. The shape of the blade is characterized by a radiused cut offset by some distance to form a curved geometry. The cut creates a curved surface with multiple asymmetries causing multiple imbalances within the blade. Imbalance due to the curve of the instrument is corrected by a non-functional asymmetry proximal to the functional asymmetry. Imbalance due to the asymmetric cross-section of the blade is corrected by the appropriate selection of the volume and location of material removed from a functional asymmetry. The shape of the blade in one embodiment of the present invention is characterized by two radiused cuts offset by some distance to form a curved and potentially tapered geometry. These two cuts create curved surfaces including a concave surface and a convex surface. The length of the radiused cuts affects, in part, the acoustic balancing of the transverse motion induced by the curved shape.

Claims

1. An ultrasonic clamp coagulator apparatus comprising:

a housing, said housing comprising an actuator;

an outer tube having a proximal end joined to said housing, and a distal end, said outer tube defining a longitudinal axis;

an actuating element reciprocably positioned within said outer tube, said actuating element operatively connected to said actuator;

an ultrasonic waveguide positioned within said outer tube, said ultrasonic waveguide having a curved end-effector defining a vertical plane of asymmetry extending distally from said distal end of said outer tube, wherein said end-effector comprises a broad edge and a narrow edge, wherein said narrow edge is defined by the intersection of a first surface and a second surface, wherein said first surface extends proximally into said end-effector defining a length of said first surface; and

a clamp arm pivotally mounted on said distal end of said outer tube for pivotal movement with respect to said end-effector for clamping tissue between said clamp arm and said end-effector, said pivotal movement occurring about a horizontal axis, the arc of said pivotal movement of said clamp arm defined in said vertical plane, said vertical plane having a vertical axis orthogonal to both said longitudinal axis and said horizontal axis, said clamp arm operatively connected to said actuating element so that reciprocal movement of said actuating element pivots said clamp arm along said vertical plane;

wherein said length of said first surface balances said waveguide such that excursion of said end-effector is minimized in said vertical plane.

2. An ultrasonic clamp coagulator apparatus according to claim 1, wherein excursion of said end-effector along said vertical axis is limited to less than 15%.

3. An ultrasonic clamp coagulator apparatus according to claim 1, wherein excursion of said end-effector along said vertical axis is limited to less than 10%.

4. An ultrasonic clamp coagulator apparatus according to claim 1, wherein excursion of said end-effector along said vertical axis is limited to less than 5%.

5. The ultrasonic clamp coagulator apparatus of claim 1, wherein the end-effector lies in a plane perpendicular to the vertical plane of asymmetry.

6. The ultrasonic clamp coagulator apparatus of claim 1 further comprising a rotatable member operatively associated with the waveguide, the clamp arm and the end-effector, the rotatable member being rotatable to cause corresponding rotation of the clamp arm and the end-effector blade about the longitudinal axis.

7. The ultrasonic clamp coagulator apparatus of claim 1 further comprising a damping member positioned adjacent to the waveguide to dampen out unwanted torque generated by the end-effector.

8. The ultrasonic clamp coagulator apparatus of claim 1, wherein the clamp pad further comprises a tissue pad having a tissue contacting surface.

9. The ultrasonic clamp coagulator apparatus of claim 8, wherein the tissue pad comprises grooves on the tissue contacting surface in a substantial perpendicular relationship with a tissue contacting surface on the curved end-effector.