Interface joint for an electrosurgical apparatus

Abstract

An interface joint with one or both of a needle actuation mechanism or an integrated shaft rotation mechanism. The interface joint comprises a flexible shaft between a housing and an electrosurgical instrument, e.g. for conveying power and/or fluid therebetween. The needle actuation mechanism comprises an actuation rod extending out of the housing and an actuator movably mounted on the housing. The shaft rotation mechanism comprises a rotation actuator rotatably mounted on the housing and operably coupled to the flexible shaft. Providing an integrated shaft rotation mechanism may obviate the need for a separate torque transmission unit. The improved needle actuation mechanism may use a pivoting connection to enable longer needle extension distances to be achieved for a given actuation distance.

1 . An interface joint for interconnecting an electrosurgical generator and an electrosurgical instrument, the interface joint comprising:
 a housing made of electrically insulating material, the housing having:
 a first inlet for receiving radiofrequency (RF) electromagnetic (EM) energy or microwave frequency EM energy from the electrosurgical generator, 
 a second inlet for receiving fluid, and 
 an outlet; 
   a flexible shaft for connecting the housing to the electrosurgical instrument, the flexible shaft extending through the outlet and having a longitudinal passage therein, which provides a fluid flow path that is in fluid communication with the second inlet, and which conveys a coaxial transmission line that is connected to the first inlet;   an actuation mechanism operably connected to the electrosurgical instrument to control deployment of a fluid delivery structure, the actuation mechanism comprising:
 an actuation rod extending out of the housing through the outlet, 
 an actuator movably mounted on the housing and connected to the actuation rod; and 
   a shaft rotation mechanism for rotating the flexible shaft relative to the housing, the shaft rotation mechanism comprising a rotation actuator rotatably mounted on the housing and operably coupled to the flexible shaft.   
     
     
         2 . An interface joint according to  claim 1 , wherein the actuation rod extends through the longitudinal passage of the flexible shaft. 
     
     
         3 . An interface joint according to  claim 1 , wherein the rotation actuator comprises a collar mounted around a distal portion of the housing. 
     
     
         4 . An interface joint according to  claim 1 , wherein the rotation actuator is rotatable relative to the housing around an axis that is aligned with a direction in which the flexible shaft passes through the outlet. 
     
     
         5 . An interface joint according to  claim 1 , wherein the housing includes an internal watertight branched conduit that provides a fluid flow path between the second inlet and the outlet, the branched conduit comprising:
 a main conduit fixed to the housing, and   a rotating luer lock, fitting rotatably mounted to a distal end of the main conduit,   wherein the flexible shaft is non-rotatably coupled to the rotating luer lock fitting, and   wherein the rotation actuator is operable to rotate the rotating luer lock fitting relative to the main conduit.   
     
     
         6 . An interface joint for interconnecting an electrosurgical generator and an electrosurgical instrument, the interface joint comprising:
 a housing made of electrically insulating material, the housing having:
 a first inlet for receiving radiofrequency (RF) electromagnetic (EM) ene rgy or microwave frequency EM energy from the electrosurgical generator, 
 a second inlet for receiving fluid, and 
 an outlet; 
   a flexible shaft for connecting the housing to the electrosurgical instrument, the flexible shaft extending through the outlet and having a longitudinal passage therein, which provides a fluid flow path that is in fluid communication with the second inlet, and which conveys a coaxial transmission line that is connected to the first inlet;   an actuation mechanism operably connected to the electrosurgical instrument to control deployment of a fluid delivery structure, the actuation mechanism comprising:
 an actuation rod extending out of the housing through the outlet, 
 an actuator arm pivotably mounted on the housing, the actuator arm having a first portion that protrudes from the housing, and a second portion operably connected to the actuation rod. 
   
     
     
         7 . An interface joint according to  claim 6 , wherein the actuation mechanism comprises a guide element slidably mounted in a reciprocal manner with respect to the housing, wherein the guide element is connected to a proximal end of the actuation rod, and wherein the second portion of the actuator arm is connected to the guide element by a drive arm. 
     
     
         8 . An interface joint according to  claim 7 , wherein the housing, comprises a track for constraining the guide element to be movable only in a longitudinal direction that is aligned with a direction in which the flexible shaft passes through the outlet. 
     
     
         9 . An interface joint according to  claim 6 , wherein the actuator arm is connected to the housing at a pivot point, and wherein the second portion is further from the pivot point than the first portion. 
     
     
         10 . An interface joint according to  claim 6 , wherein the housing includes an internal watertight branched conduit that provides a fluid flow path between the second inlet and the outlet. 
     
     
         11 . An interface joint according to  claim 5 , wherein the branched conduit has a first port adjacent to the first inlet for admitting the coaxial cable. 
     
     
         12 . An interface joint according to  claim 11 , wherein the first port comprises a plug which defines a watertight passage for the coaxial cable. 
     
     
         13 . An interface joint according to  claim 11 , wherein the branched conduit defines a second port adjacent the actuation mechanism for admitting the actuation rod. 
     
     
         14 . An interface joint according to  claim 13 , wherein the second port comprises a plug which defines a watertight passage for the actuation rod. 
     
     
         15 . An interface joint according to  claim 1  having a connector rotatably mounted at the first inlet, wherein the connector Is arranged to connect to a coaxial cable. 
     
     
         16 . An interface joint according to  claim 15 , wherein the connector is mounted within a bearing unit that is fixed to the housing. 
     
     
         17 . An interface joint according to  claim 1 , wherein a distal end of the actuation rod is connected to a proximal end of a needle ferrule, which has an internal volume in fluid communication with the fluid flow path through the flexible shaft, and wherein a needle is mounted in the distal end of the needle ferrule, the needle being in fluid communication with the internal volume.