Surgical instruments with articulating shafts

Abstract

Various example embodiments described herein are directed to articulating surgical instruments for treating tissue comprising an end effector and a shaft extending proximally from the end effector along a longitudinal axis. In certain embodiments, the shaft comprises a plurality of transverse spacer members as well as first and second rotatable members extending through at least a portion of the plurality of transverse spacer members. The first and second rotatable members may both be biased away from the longitudinal axis such that their respective directions of bias vary with rotation of the first rotatable member. When the respective directions of bias of the first and second rotatable members oppose one another, the shaft may be substantially straight. When the respective directions of bias of the first and second rotatable members are aligned with one another, the shaft may articulate away from the longitudinal axis in the direction of the alignment.

What is claimed is: 
     
         1 . An articulatable surgical instrument comprising:
 an end effector to treat tissue;   a shaft extending proximally from the end effector along a longitudinal axis, wherein the shaft comprises:
 a plurality of transverse spacer members; 
 a first rotatable member extending through at least a portion of the plurality of transverse spacer members parallel to the longitudinal axis, wherein the first rotatable member is biased away from the longitudinal axis, and wherein a direction of the bias of the first rotatable member varies with rotation of the first rotatable member; 
 a second rotatable member extending through at least a portion of the plurality of transverse spacer members parallel to the longitudinal axis and offset from the first rotatable member along a direction perpendicular to the longitudinal axis, wherein the second rotatable member is biased away from the longitudinal shaft, wherein a direction of the bias of the second rotatable member varies with rotation of the second rotatable member, wherein the shaft is substantially straight when the first and second rotatable members are rotated such that the direction of the bias of the first rotatable member and the direction of the bias of the second rotatable member oppose one another, and wherein the shaft articulates in a first direction away from the longitudinal axis when the first and second rotatable members are rotated such that the direction of the bias of the first rotatable member and the direction of the bias of the second rotatable member are aligned with one another in the first direction. 
   
     
     
         2 . The surgical instrument of  claim 1 , further comprising a third rotatable member extending through the plurality of transverse spacer members parallel to the longitudinal axis and offset from the first and second rotatable members along a direction perpendicular to the longitudinal axis, wherein the third rotatable member is biased away from the longitudinal shaft, wherein a direction of the bias of the third rotatable member varies with rotation of the third rotatable member, wherein the shaft is substantially straight when the first, second and third rotatable members are rotated such that the direction of the bias of the first rotatable member, the direction of the bias of the second rotatable member, and the direction of bias of the third rotatable member oppose each another, and wherein the shaft articulates in the first direction away from the longitudinal axis when the first, second rotatable members are rotated such that the direction of the bias of the first rotatable member, the direction of bias of the second rotatable member and the direction of the bias of the third rotatable member are aligned with one another in the first direction. 
     
     
         3 . The surgical instrument of  claim 1 , wherein the first rotatable member, the second rotatable member and the longitudinal axis are centered on a common plane. 
     
     
         4 . The surgical instrument of  claim 3 , wherein the first direction is in the common plane. 
     
     
         5 . The surgical instrument of  claim 3 , wherein the first direction is outside of the common plane. 
     
     
         6 . The surgical instrument of  claim 3 , wherein the direction of the bias of the first rotatable member and the direction of the bias of the second rotatable member oppose one another when the direction of the bias of the first rotatable member and the direction of the bias of the second rotatable member are opposite one another. 
     
     
         7 . The surgical instrument of  claim 1 , wherein each of transverse spacer members defines a disk centered on the longitudinal axis, wherein the disk defines first and second openings for receiving the first and second rotatable members. 
     
     
         8 . The surgical instrument of  claim 1 , wherein the end effector comprises an ultrasonic blade mechanically coupled to a waveguide extending through at least a portion of the plurality of transverse spacer members. 
     
     
         9 . The surgical instrument of  claim 1 , wherein the end effector comprises at least one electrode to treat tissue. 
     
     
         10 . An articulatable surgical instrument for treating tissue, the instrument comprising:
 an end effector, the end effector comprising an energy device selected from the group consisting of at least one electrosurgical electrode and an ultrasonic blade; and   a shaft extending proximally from the end effector along a longitudinal axis, wherein the shaft comprises:
 a proximal tube defining a proximal clevis at a distal end of the proximal hollow tube, the proximal clevis comprising first and second clevis members; 
 a distal tube defining a distal clevis at a proximal end of the articulation tube, the distal clevis comprising first and second clevis members, wherein the distal clevis is coupled to the proximal clevis such that the distal tube is pivotable relative to the proximal tube about an interface between the distal tube and the proximal tube, and wherein the first clevis member of the distal clevis comprises a first plurality of teeth; 
 a rotatable inner tube positioned within the proximal tube and rotatable about the longitudinal axis, wherein a distal end of the inner tube defines a second plurality of teeth positioned to interlock with the first plurality of teeth such that rotation of the inner tube about the longitudinal axis causes the distal tube to pivot about the interface between the distal tube and the proximal tube. 
   
     
     
         11 . The instrument of  claim 10 , wherein the first plurality of teeth are proximally directed and the second plurality of teeth are distally directed. 
     
     
         12 . The instrument of  claim 10 , wherein the first plurality of teeth are integral to the first clevis member of the distal clevis. 
     
     
         13 . The instrument of  claim 10 , wherein first and second members of the distal clevis are positioned inside the first and second members of the proximal clevis. 
     
     
         14 . The instrument of  claim 10 , wherein the end effector comprises an ultrasonic blade, and further comprising an ultrasonic waveguide extending through the shaft to the ultrasonic blade. 
     
     
         15 . The instrument of  claim 14 , wherein the waveguide comprises a first flexible portion and a second rigid portion, wherein the first flexible portion is positioned at about the distal and proximal clevises. 
     
     
         16 . An articulatable surgical instrument for treating tissue, the instrument comprising:
 an end effector; and   a shaft extending proximally from the end effector along a longitudinal axis, wherein the shaft comprises:
 a proximal tube; and 
 a distal tube, wherein the distal tube and the proximal tube are pivotably coupled at a first hinge interface; 
 a translating member extending through the proximal tube and coupled to the distal tube at a second hinge interface such that translation of the translating member along the longitudinal axis causes the proximal tube to pivot relative to the distal tube. 
   
     
     
         17 . The surgical instrument of  claim 16 , wherein the first hinge interface is offset from the longitudinal axis, and wherein the second hinge interface is also offset from the longitudinal axis opposite the first hinge interface. 
     
     
         18 . The surgical instrument of  claim 17 , wherein distally directed movement of the translating member causes the distal tube to pivot away from the longitudinal axis, and wherein proximally directed movement of the translating member causes the distal tube to pivot towards the longitudinal axis. 
     
     
         19 . The surgical instrument of  claim 16 , wherein the translating member defines a hollow tube positioned within the proximal tube. 
     
     
         20 . The surgical instrument of  claim 19 , wherein the distal tube comprises first and second pin portions extending about perpendicular to the longitudinal axis, and wherein the translating member defines first and second openings for receiving the first and second pin portions. 
     
     
         21 . The surgical instrument of  claim 20 , wherein the first and second openings are larger than the cross-sectional diameters of the first and second pin portions such that the first and second pin portions are movable within the first and second openings. 
     
     
         22 . The surgical instrument of  claim 16 , wherein the translating member defines a rod positioned within the proximal tube. 
     
     
         23 . The surgical instrument of  claim 22 , wherein the rod comprises first and second pin portions extending about perpendicular to the longitudinal axis, and wherein the distal tube defines first and second openings for receiving the first and second pin portions. 
     
     
         24 . The surgical instrument of  claim 23 , wherein the first and second openings are larger than the cross-sectional diameters of the first and second pin portions such that the first and second pin portions are movable within the first and second openings. 
     
     
         25 . The surgical instrument of  claim 16 , wherein the first hinge interface comprises a pin extending through the proximal tube and the distal tube. 
     
     
         26 . The instrument of  claim 16 , wherein the end effector comprises an ultrasonic blade, and further comprising an ultrasonic waveguide extending through the shaft to the ultrasonic blade. 
     
     
         27 . The instrument of  claim 26 , wherein the waveguide comprises a first flexible portion and a second rigid portion, wherein the first flexible portion is positioned along the longitudinal axis at about the first hinge interface. 
     
     
         28 . An articulatable surgical instrument for treating tissue, the instrument comprising:
 an end effector comprising an ultrasonic blade; and   a shaft extending proximally from the end effector along a longitudinal axis, wherein the shaft comprises:
 a proximal tube; and 
 a distal tube, wherein the distal tube and the proximal tube are pivotably coupled at a first hinge interface; 
   a waveguide mechanically coupled to the ultrasonic blade and extending proximally through the shaft, wherein the waveguide defines a flexible portion positioned at about the first hinge interface;   a rigid translating member extending through at least a portion of the proximal tube;   a linkage member defining a proximal end pivotably coupled to the proximal tube and a distal end pivotably coupled to the distal tube such that distal translation of the translating member causes the distal tube to pivot about the first hinge interface away from the translating member.   
     
     
         29 . The surgical instrument of  claim 28 , wherein proximal translation of the translating member causes the distal tube to pivot about the first hinge interface towards the translating member. 
     
     
         30 . The surgical instrument of  claim 28 , wherein the waveguide is coupled to the proximal tube at a first coupling point proximal from the flexible portion of the waveguide, and wherein the waveguide is coupled to the distal tube at a second coupling point distal from the flexible portion. 
     
     
         31 . The surgical instrument of  claim 30 , wherein the first and second coupling points are positioned at nodes of the waveguide. 
     
     
         32 . An articulatable surgical instrument for treating tissue, the instrument comprising:
 an end effector comprising an ultrasonic blade; and   a shaft extending proximally from the end effector along a longitudinal axis;   an articulation neck defining a proximal end coupled to the shaft and a distal end coupled to the end effector, wherein the articulation neck comprises a plurality of hollow neck members, wherein a first hollow neck member selected from the plurality of hollow neck members defines a proximal end configured to receive a distal end of a second hollow neck member selected from the plurality of hollow neck members such that the first and second hollow neck members are pivotably coupled to each other; and   a waveguide extending proximally from the ultrasonic blade through the articulation neck and the shaft, wherein the waveguide comprises a flexible portion positioned at about the articulation neck.   
     
     
         33 . The surgical instrument of  claim 32 , further comprising a first translating member coupled to the end effector and extending proximally through the articulation neck and shaft such that proximal translation of the first translating member causes the end effector to pivot about the flexible neck towards the first translating member. 
     
     
         34 . The surgical instrument of  claim 33 , further comprising a second translating member coupled to the end effector and extending proximally through the articulation neck and shaft such that proximal translation of the second translating member causes the end effector to pivot about the flexible neck towards the second translating member. 
     
     
         35 . The surgical instrument of  claim 32 , further comprising first and second translating members coupled to the end effector and extending proximally through the articulation neck and shaft, wherein proximal translation of the first and second translating members puts the plurality of hollow neck members in compression, preventing articulation, and wherein distal translation of the first and second translating members releases the plurality of hollow neck members from compression, allowing articulation.