Ultrasonic surgical instrument with sliding blade sheath

Abstract

A surgical instrument includes a gripping assembly, a shaft assembly, an end effector, and a pivoting member. The gripping assembly defines a first opening for receiving a finger or a thumb of a user. The gripping assembly includes a first deformable feature that is configured to be moved in order to increase or decrease a cross-sectional area of the first opening. The shaft assembly extends distally from the gripping assembly. The end effector is positioned at a distal end of the shaft assembly and includes a first member. The pivoting member is pivotably coupled with the shaft assembly. The pivoting member is pivotable with respect to the first member of the end effector between an open position and a closed position to thereby clamp tissue between the first member and the pivoting member.

1 .- 20 . (canceled) 
     
     
         21 . A surgical instrument comprising:
 (a) a body;   (b) a shaft assembly extending distally from the body;   (c) an end effector at a distal end of the shaft assembly, wherein the end effector comprises:
 (i) an ultrasonic blade, and 
 (ii) a clamp arm comprising a first surface, wherein the clamp arm is pivotable relative to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the ultrasonic blade and the clamp arm; and 
   (d) a sheath that angularly envelops the ultrasonic blade, wherein the sheath is a movable between a retracted position and an extended position relative to the end effector without touching the ultrasonic blade, wherein the sheath comprises a second surface that faces away from the first surface of the clamp arm in the extended position, wherein the second surface of the sheath and the first surface of the clamp arm are configured to bluntly dissect tissue in response to pivoting the clamp arm toward the open position while the sheath is in the extended position.   
     
     
         22 . The surgical instrument of  claim 21 , wherein the first surface comprises a textured surface. 
     
     
         23 . The surgical instrument of  claim 22 , wherein the textured surface comprises a knurled surface. 
     
     
         24 . The surgical instrument of  claim 21 , wherein the body comprises a switch configured to transition the sheath between the retracted position and the extended position. 
     
     
         25 . The surgical instrument of  claim 24 , wherein the switch is slidably between a proximal position and a distal position. 
     
     
         26 . The surgical instrument of  claim 25 , wherein the proximal position of the switch corresponds to the retracted position of the sheath, wherein the distal position of the switch corresponds to the extended position of the sheath. 
     
     
         27 . The surgical instrument of  claim 26 , wherein a mechanical linkage extends between the sheath and the switch. 
     
     
         28 . The surgical instrument of  claim 21 , wherein the body comprises a gripping assembly comprising a thumb grip and a finger grip. 
     
     
         29 . The surgical instrument of  claim 28 , wherein the thumb grip in connected with the clamp arm such that movement of the thumb grip drives movement of the clamp arm. 
     
     
         30 . The surgical instrument of  claim 29 , wherein the finger grip in connected with the ultrasonic blade such that movement of the finger grip drives movement of the ultrasonic blade. 
     
     
         31 . The surgical instrument of  claim 30 , wherein the finger grip and the thumb grip are pivotally coupled to each other. 
     
     
         32 . The surgical instrument of  claim 21 , wherein the body further comprises an activation button configured to ultrasonically activate the ultrasonic blade. 
     
     
         33 . The surgical instrument of  claim 21 , wherein the body further comprises a transducer assembly in ultrasonic communication with the ultrasonic blade. 
     
     
         34 . The surgical instrument of  claim 33 , wherein the ultrasonic transducer assembly is configured to selectively couple with a generator. 
     
     
         35 . The surgical instrument of  claim 21 , where the sheath partially envelopes the ultrasonic blade in the extended position such that the ultrasonic blade and the clamp arm are configured to grasp and sever tissue while the sheath is in the extended position. 
     
     
         36 . A surgical instrument comprising:
 (a) a body;   (b) a shaft assembly extending distally from the body;   (c) an end effector at a distal end of the shaft assembly, wherein the end effector comprises:
 (i) an ultrasonic blade, and 
 (ii) a clamp arm, wherein the clamp arm is pivotable relative to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the ultrasonic blade and the clamp arm, wherein the end effector defines a first cross sectional area when the clamp arm is in the closed position; and 
   (d) a sheath at least partially covering the ultrasonic blade and movable between a first position and a second position relative to the end effector without touching the end effector, wherein the end effector defines a second cross sectional area when the sheath is in the second position and the clamp arm is in the closed position.   
     
     
         37 . The surgical instrument of  claim 36 , wherein the sheath comprises a first knurled surface facing away from the clamp arm in the second position. 
     
     
         38 . The surgical instrument of  claim 37 , wherein the clamp arm comprises a second knurled surface facing away from the first knurled surface. 
     
     
         39 . The surgical instrument of  claim 38 , further comprising a mechanical link extending between the sheath and the body. 
     
     
         40 . A surgical instrument comprising:
 (a) a body;   (b) a shaft assembly extending distally from the body;   (c) an end effector at a distal end of the shaft assembly, wherein the end effector comprises:
 (i) an ultrasonic blade, and 
   (ii) a clamp arm comprising a first textured surface, wherein the clamp arm is pivotable relative to the ultrasonic blade from an open position to a closed position to thereby clamp tissue between the ultrasonic blade and the clamp arm, wherein the end effector defines a first cross sectional area when the clamp arm is in the closed position; and   (d) a sheath comprising a second textured surface, wherein the sheath at least partially covers the ultrasonic blade such that the second textured surface faces away from the first textured surface of the clamp arm, wherein the sheath is configured to move between a first position and a second position relative to the end effector without touching the end effector, wherein the end effector defines a second cross sectional area when the sheath is in the second position and the clamp arm is in the closed position.