Curved cannula instrument

Abstract

A robotic surgical system is configured with rigid, curved cannulas that extend through the same opening into a patient's body. Surgical instruments with passively flexible shafts extend through the curved cannulas. Force isolation elements within the flexible shafts prevent shaft bending from affecting end effector actuation elements that extends through the shafts. The cannulas are oriented to direct the instruments towards a surgical site. Various port features that support the curved cannulas within the single opening are disclosed. Cannula support fixtures that support the cannulas during insertion into the single opening and mounting to robotic manipulators are disclosed. A teleoperation control system that moves the curved cannulas and their associated instruments in a manner that allows a surgeon to experience intuitive control is disclosed.

1 - 23 . (canceled) 
     
     
         24 . A surgical system comprising:
 a rigid cannula comprising at least a portion having a curved longitudinal axis; and   a surgical instrument configured to be advanced through the cannula, the instrument comprising:
 a proximal end transmission mechanism, wherein the transmission mechanism comprises a force transmission interface to a teleoperated manipulator, 
 a distal end surgical end effector, and 
 a shaft that extends from the transmission mechanism to the surgical end effector, 
 wherein the shaft comprises a drive element and a force isolation element that isolates the drive element from movement as a result of a bending of the shaft as the shaft translates through a portion of the cannula. 
   
     
     
         25 . The surgical system of  claim 24 , wherein the shaft is passively flexible. 
     
     
         26 . The surgical system of  claim 24 , wherein the force isolation element comprises stainless steel. 
     
     
         27 . The surgical system of  claim 24 , wherein the force isolation element comprises a thermoplastic. 
     
     
         28 . The surgical system of  claim 24 , wherein the force isolation element has a diameter that is substantially equal to a diameter of the drive element. 
     
     
         29 . The surgical system of  claim 24 , wherein the instrument is a non-wristed instrument. 
     
     
         30 . The surgical system of  claim 24 , wherein the transmission mechanism comprises a roll drive element coupled to roll the shaft within the cannula. 
     
     
         31 . The surgical system of  claim 24 , wherein the end effector comprises a movable component and the drive element is coupled to the movable component. 
     
     
         32 . The surgical system of  claim 24 , wherein the shaft further comprises a support tube comprising a central channel and at least one additional channel offset from the central channel. 
     
     
         33 . The surgical system of  claim 32 ,
 wherein the shaft further comprises a chamber at a distal end of the shaft; and   wherein the additional channel is a flush channel configured to direct a flow of flush fluid in a distal direction within the shaft through the flush channel and the chamber is configured to redirect the flush fluid to flow in a proximal direction within the shaft.   
     
     
         34 . The surgical system of  claim 32 , wherein the drive element extends through the central channel and the force isolation element extends through the additional channel. 
     
     
         35 . The surgical system of  claim 24 ,
 wherein the shaft comprises a proximal section, a middle section, and a distal section; and   wherein a stiffness of the distal section of the shaft is greater than a stiffness of the middle section of the shaft.   
     
     
         36 . The surgical system of  claim 24 , wherein a stiffness of the shaft is substantially constant along a length of the shaft. 
     
     
         37 . The surgical system of  claim 24 , wherein the drive element comprises first and second tension elements coupled between the transmission mechanism and the end effector. 
     
     
         38 . The surgical system of  claim 24 , wherein the drive element is a push/pull drive element. 
     
     
         39 . The surgical system of  claim 24 , wherein the instrument further comprises a wrist mechanism and at least a second drive element to actuate the wrist mechanism. 
     
     
         40 . The surgical system of  claim 24 , wherein the force isolation element comprises a rod. 
     
     
         41 . The surgical system of  claim 24 , wherein the force isolation element and the drive element share a same longitudinal axis. 
     
     
         42 . A surgical system comprising:
 a rigid cannula comprising at least a portion having a curved longitudinal axis; and   a surgical instrument configured to be advanced through the cannula, the instrument comprising:
 a proximal end transmission mechanism, 
 a distal end surgical end effector, and 
 a shaft that extends from the transmission mechanism to the surgical end effector, the shaft comprising:
 a drive element, 
 a force isolation element, wherein the at least one force isolation element isolates the drive element from movement as a result of bending of the shaft as the shaft translates through the cannula, 
 wherein a longitudinal axis of the force isolation element is substantially parallel to and spaced apart from a longitudinal axis of the drive element. 
 
   
     
     
         43 . The surgical system of  claim 42 , wherein the shaft is passively flexible. 
     
     
         44 . The surgical system of  claim 42 , further comprising a support tube having a plurality of channels, wherein the drive element extends through one of the plurality of channels. 
     
     
         45 . The surgical system of  claim 44 , further comprising a fluid flush path extending through the support tube and parallel to the drive element, wherein the fluid flush path extends through at least one of the plurality of channels. 
     
     
         46 . The surgical system of  claim 44 , wherein the at least one force isolation element extends through at least one of the plurality of channels. 
     
     
         47 . The surgical system of  claim 44 , wherein the plurality of channels of the support tube comprise a central channel and a plurality of channels offset from the central channel. 
     
     
         48 . The surgical system of  claim 47 , wherein the drive element extends through the central channel and the force isolation element extends through one of the plurality of channels offset from the central channel. 
     
     
         49 . The surgical system of  claim 44 , the instrument further comprising a wrist mechanism and a second drive element to actuate the wrist, wherein the second drive element extends through one of the plurality of channels offset from the central channel. 
     
     
         50 . The surgical system of  claim 42 , wherein the transmission mechanism comprises a force transmission interface to a teleoperated manipulator. 
     
     
         51 . A surgical system comprising:
 a rigid cannula comprising at least a portion having a curved longitudinal axis; and   a surgical instrument configured to be advanced through the cannula, the instrument comprising:
 a shaft; 
 an end effector operatively connected to a distal end of the shaft; 
 means for actuating the end effector; and 
 means for substantially maintaining a stiffness of the shaft during bending of the shaft. 
   
     
     
         52 . The surgical system of  claim 51 , wherein the means for actuating the end effector comprises a drive element for moving a movable portion of the end effector. 
     
     
         53 . The surgical system of  claim 52 , wherein the means for actuating further comprises a transmission mechanism operatively connected to a proximal end of the shaft, wherein the drive element is connected to the transmission mechanism, and wherein the transmission mechanism comprises a force transmission interface to a teleoperated manipulator. 
     
     
         54 . The surgical system of  claim 51 , wherein the means for substantially maintaining the stiffness of the shaft comprises a force isolation element. 
     
     
         55 . The surgical system of  claim 54 , wherein the force isolation element comprises a rod. 
     
     
         56 . The surgical system of  claim 55 , wherein the rod comprises a stainless steel material or a thermoplastic material. 
     
     
         57 . The surgical system of  claim 52 , wherein the shaft includes a support tube having a plurality of channels, and wherein the drive element extends through one of the plurality of channels. 
     
     
         58 . The surgical system of  claim 57 , wherein a size of an outer diameter of the force isolation element is substantially equal to a size of an outer diameter of the drive element. 
     
     
         59 . The surgical system of  claim 51 , wherein a bending stiffness of the shaft is in the range of about 1 lb-in 2  to about 4 lb-in 2 .