Ultrasonic surgical instrument blades

1. A surgical instrument, comprising:

a transducer configured to produce vibrations at a predetermined frequency;

a waveguide coupled to the transducer and defining a longitudinal axis;

a tube comprising an outer surface, wherein the waveguide extends through the tube; and

an end effector, comprising:

a surgical blade extending from the waveguide, wherein the surgical blade is asymmetric relative to the longitudinal axis, and wherein the surgical blade comprises:

a cutting edge on a first side of the longitudinal axis, wherein the cutting edge comprises a proximal end;

an atraumatic surface on a second side of the longitudinal axis;

a distal tip; and

a treatment portion extending between the proximal end of the cutting edge and the distal tip; and wherein the surgical instrument further comprises:

a protective sheath extending around at least a portion of the tube and along at least a portion of the surgical blade to the treatment portion.

2. The surgical instrument of claim 1 , wherein the atraumatic surface comprises an arcuate surface.

3. The surgical instrument of claim 1 , wherein the atraumatic surface comprises a dull surface.

4. The surgical instrument of claim 3 , wherein the cutting edge comprises a sharp edge.

5. The surgical instrument of claim 1 , wherein the protective sheath comprises a polymeric material.

6. The surgical instrument of claim 5 , wherein the protective sheath comprises a coating on a portion of the surgical blade.

7. The surgical instrument of claim 5 , wherein the protective sheath is molded over a portion of the surgical blade.

8. The surgical instrument of claim 1 , wherein the protective sheath is permanently attached to the surgical blade.

9. The surgical instrument of claim 8 , wherein the protective sheath extends around the distal tip of the surgical blade.

10. The surgical instrument of claim 1 , wherein the protective sheath is spaced apart from the atraumatic surface by an air gap.

11. The surgical instrument of claim 10 , further comprising a spring in the air gap between the protective sheath and the atraumatic surface.

12. The surgical instrument of claim 10 , further comprising an irrigation source fluidically coupled to the air gap.

13. The surgical instrument of claim 1 , wherein the protective sheath is movable between an undeployed position and a deployed position relative to the surgical blade.

14. The surgical instrument of claim 13 , wherein the protective sheath extends around the distal tip when in the deployed position.

15. The surgical instrument of claim 13 , further comprising a handle, wherein the handle comprises an actuator configured to move the protective sheath between the undeployed position and the deployed position.

16. The surgical instrument of claim 15 , wherein the actuator comprises a pivotable lever.

17. The surgical instrument of claim 15 , wherein the actuator comprises a slide button.

18. The surgical instrument of claim 1 , wherein the protective sheath comprises a plurality of bumps extending toward the surgical blade.

19. The surgical instrument of claim 1 , wherein the protective sheath comprises an outside surface facing away from the surgical blade, and wherein the outside surface comprises a distal convex portion and a proximal concave portion.

20. The surgical instrument of claim 1 , wherein the end effector further comprising a non-vibrating clamp arm movable between an open position and a clamped position relative to the surgical blade.

21. A surgical instrument, comprising:

a transducer configured to produce vibrations at a predetermined frequency;

a waveguide coupled to the transducer and defining a longitudinal axis;

a tube comprising an outer surface, wherein the waveguide extends through the tube; and

an end effector, comprising:

a surgical blade extending from the waveguide, wherein the surgical blade is asymmetric relative to the longitudinal axis, and wherein the surgical blade comprises:

a sharp edge on a first side of the longitudinal axis, wherein the sharp edge comprises a proximal end;

a dull surface on a second side of the longitudinal axis;

a distal tip; and

a treatment portion extending between the proximal end of the sharp edge and the distal tip; and wherein the surgical instrument further comprises:

a protective sheath extending around at least a portion of the tube and along at least a portion of the surgical blade to the treatment portion.

22. A surgical instrument, comprising:

a transducer configured to produce vibrations at a predetermined frequency;

a waveguide coupled to the transducer and defining a longitudinal axis;

a tube, wherein the waveguide extends through the tube; and

an end effector, comprising:

a surgical blade extending from the waveguide, wherein the surgical blade is asymmetric relative to the longitudinal axis, and wherein the surgical blade comprises a tissue treatment portion comprising:

a cutting edge on a first side of the longitudinal axis, wherein the cutting edge comprises a proximal end;

an atraumatic surface on a second side of the longitudinal axis;

a distal tip; and

a treatment portion extending between the proximal end of the cutting edge and the distal tip; and wherein the surgical instrument further comprises:

means for shielding tissue from the treatment portion of the surgical blade positioned around at least a portion of the tube.