Surgical instrument with multi-function button

1. An ultrasonic instrument comprising:

(a) an actuation assembly, wherein the actuation assembly comprises an activation member, wherein the activation member is operable to move angularly in a first direction about a first axis to select a mode of operation;

(b) a shaft assembly, wherein the shaft assembly defines a longitudinal axis, wherein the shaft assembly comprises an acoustic waveguide; and

(c) an end effector comprising an ultrasonic blade, wherein the ultrasonic blade is in acoustic communication with the acoustic waveguide,

wherein the activation member is operable to move in a second direction toward the first axis to activate the end effector in the mode of operation selected by movement of the activation member in the first direction.

2. The ultrasonic instrument of claim 1 , wherein the end effector is configured to be activated in a first activation mode in response to movement of the activation member in the second direction when the activation member is in a first position, wherein the end effector is configured to be activated in a second activation mode in response to movement of the activation member in the second direction when the activation member is in a second position.

3. The ultrasonic instrument of claim 1 , wherein the activation member comprises a button, wherein the button is movable angularly in the first direction along a lateral plane.

4. The ultrasonic instrument of claim 3 , wherein the button is pivotable in the first direction about the first axis along the lateral plane, wherein the first axis is perpendicular to the longitudinal axis of the shaft assembly.

5. The ultrasonic instrument of claim 4 , wherein the pivotable button is configured to pivot in the first direction between a first position, a second position, and a third position, wherein the second position is between the first and third positions.

6. The ultrasonic instrument of claim 5 , wherein the pivotable button is resiliently biased to the second position.

7. The ultrasonic instrument of claim 5 , wherein the pivotable button is inoperable to activate the end effector when the pivotable button is in the second position.

8. The ultrasonic instrument of claim 1 , wherein the activation member is configured to select between a first mode of operation and a second mode of operation, wherein the end effector is configured to apply ultrasonic energy to tissue at a first power level in the first mode of operation, wherein the activation member is configured to apply ultrasonic energy to tissue at a second power level in the second mode of operation.

9. The ultrasonic instrument of claim 1 , wherein the activation member is configured to select between a first mode of operation and a second mode of operation, wherein the end effector is configured to apply ultrasonic energy to tissue in the first mode of operation, wherein the activation member is configured to apply RF energy to tissue in the second mode of operation.

10. The ultrasonic instrument of claim 1 , further comprising a body, wherein the shaft assembly extends distally from the body, wherein the body is configured to be grasped by a hand of an operator.

11. The ultrasonic instrument of claim 10 , further comprising a sensor, wherein the sensor is configured to sense whether the body is grasped by a right hand or a left hand of an operator.

12. The ultrasonic instrument of claim 1 , further comprising a body, wherein the shaft assembly extends distally from the body, further comprising a visual indicator on the body, wherein the visual indicator is configured to provide visual feedback indicating a mode of operation selected through movement of the activation member in the first direction.

13. An ultrasonic instrument comprising:

(a) a body, wherein the body comprises a pistol grip;

(b) an actuation assembly positioned distal to the pistol grip, wherein the actuation assembly comprises an activation member, wherein the activation member is operable to rotate in a first direction to select a mode of operation;

(c) a shaft assembly extending distally from the body, wherein the shaft assembly defines a longitudinal axis, wherein the shaft assembly comprises an acoustic waveguide; and

(d) an end effector comprising an ultrasonic blade, wherein the ultrasonic blade is in acoustic communication with the acoustic waveguide,

wherein the activation member is operable to move in a second direction to activate the end effector in the mode of operation selected by rotational movement of the activation member in the first direction, wherein the first and second directions are contained within the same plane.

14. The ultrasonic instrument of claim 13 , wherein the actuation assembly is configured to resist movement of the activation member in the first direction.

15. The ultrasonic instrument of claim 13 , wherein the second direction is parallel to the longitudinal axis of the shaft assembly.

16. The ultrasonic instrument of claim 13 , wherein the activation member is configured to extend inwardly into the body when moved in the second direction.

17. An ultrasonic instrument, comprising:

(a) a body;

(b) an actuation assembly, wherein the actuation assembly comprises an activation member, wherein the activation member is operable to pivot within a plane to select a mode of operation;

(c) a shaft assembly extending distally from the body, wherein the shaft assembly defines a longitudinal axis, wherein the shaft assembly comprises an acoustic waveguide; and

(d) an end effector comprising an ultrasonic blade, wherein the ultrasonic blade is in acoustic communication with the acoustic waveguide,

wherein the activation member is operable to translate within the plane to activate the end effector in the mode of operation selected by pivotal movement of the activation member.