Patent Publication Number: US-2023136246-A1

Title: Hybrid ball joint for articulation shaft of a surgical instrument

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application Ser. No. 63/274,068 filed Nov. 1, 2021, the entire contents of which being incorporated by reference herein. 
    
    
     FIELD 
     The present disclosure relates to surgical instruments and, more specifically, to linkages and joints associated with articulatable surgical instruments for use in robotic surgical systems. 
     BACKGROUND 
     Robotic surgical systems are increasingly utilized in various different surgical procedures. Some robotic surgical systems include a console supporting a robotic arm. One or more different surgical instruments may be configured for use with the robotic surgical system and selectively mountable to the robotic arm. The robotic arm provides one or more inputs to the mounted surgical instrument to enable operation of the mounted surgical instrument. 
     A surgical forceps, one type of instrument capable of being utilized with a robotic surgical system, relies on mechanical action between its jaw members to grasp, clamp, and constrict tissue. Electrosurgical forceps utilize both mechanical clamping action and energy to heat tissue to treat, e.g., coagulate, cauterize, or seal, tissue. In many instances, the end effector of the forceps must be articulated via articulation cables to properly oriented the jaw members for treating tissue. Guiding these cables and the various internal components (e.g., cutting element, drive cable, electrical connections, etc.) through the shaft can be a challenge for manufacturers. 
     SUMMARY 
     As used herein, the term “distal” refers to the portion that is being described which is farther from an operator (whether a human surgeon or a surgical robot), while the term “proximal” refers to the portion that is being described which is closer to the operator. The terms “about,” substantially,” and the like, as utilized herein, are meant to account for manufacturing, material, environmental, use, and/or measurement tolerances and variations, and in any event may encompass differences of up to 10%. Further, to the extent consistent, any of the aspects described herein may be used in conjunction with any or all of the other aspects described herein. 
     Provided in accordance with aspects of the present disclosure is an articulating surgical instrument which includes a housing having a shaft extending therefrom, the shaft having a proximal segment and a distal segment separated by an articulation section configured to articulate the distal segment relative to the proximal segment upon actuation thereof. The articulating section includes a ball joint having a plurality of opposing spherical segments, each adjacent pair of spherical segments defining a channel therebetween configured to receive an articulation cable therethrough, each channel including an angled surface on opposing sides thereof to allow articulation of each cable along a respective length thereof. The articulating section also includes a pair of casings configured to operably receive and retain the ball joint on opposing ends thereof, each casing including a chamfer defined therein configured to rotationally receive an end of the ball joint therein, each casing including a corresponding number of apertures defined therein each configured to receive a respective articulation cable therethrough. 
     In aspects according to the present disclosure, each angled surface of each channel allows the respective articulation cable to articulate from about zero degrees to about sixty degrees. 
     In aspects according to the present disclosure, the ball joint includes a central aperture defined therethrough configured to centrally guide one or more actuation or electrical components therethrough without being affected by articulation of the distal segment. In other aspects according to the present disclosure, the one or more actuation or electrical components include a drive rod, cutter rod and electrical lead wires. 
     In aspects according to the present disclosure, the opposing casings are configured to abut one another when the distal segment reaches full articulation. 
     In aspects according to the present disclosure, the ball joint is configured to receive four articulation cables arranged in opposing pairs. In other aspects according to the present disclosure, the opposing pairs of articulation cables, when taught, resist rotation of the ball joint relative to the shaft. 
     Provided in accordance with aspects of the present disclosure is an articulating section for a shaft of a surgical instrument that includes a ball joint having a plurality of opposing spherical segments, each adjacent pair of spherical segments defining a channel therebetween configured to receive an articulation cable therethrough. Each channel includes an angled surface on opposing sides thereof to allow articulation of each cable along a respective length thereof. The articulating section also includes a pair of casings configured to operably receive and retain the ball joint on opposing ends thereto. Each casing includes a chamfer defined therein configured to rotationally receive an end of the ball joint therein and a corresponding number of apertures defined therein each configured to receive a respective articulation cable therethrough. 
     In aspects according to the present disclosure, each angled surface of each channel allows the respective articulation cable to articulate from about zero degrees to about sixty degrees. 
     In aspects according to the present disclosure, the ball joint includes a central aperture defined therethrough configured to centrally guide one or more actuation or electrical components therethrough without being affected by articulation of the articulating section. In other aspects according to the present disclosure, the one or more actuation or electrical components include a drive rod, cutter rod and electrical lead wires. 
     In aspects according to the present disclosure, the opposing casings are configured to abut one another when the articulating section reaches full articulation. 
     In aspects according to the present disclosure, the ball joint is configured to receive four articulation cables arranged in opposing pairs. In other aspects according to the present disclosure, the opposing pairs of articulation cables, when taught, resist rotation of the ball joint relative to a shaft of the surgical instrument. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects and features of the present disclosure are described hereinbelow with reference to the drawings wherein: 
         FIG.  1    is a perspective view of a surgical instrument in accordance with the present disclosure configured for mounting on a robotic arm of a robotic surgical system and including a shaft with an articulation section; 
         FIG.  2    is a rear perspective view of a proximal portion of the surgical instrument of  FIG.  1    with an outer housing removed; 
         FIG.  3    is a schematic illustration of an exemplary robotic surgical system configured to releasably receive the surgical instrument of  FIG.  1   ; 
         FIG.  4    is an enlarged, front view of a ball joint for use with the articulation section of  FIG.  1   ; 
         FIG.  5    is an enlarged, perspective view of the ball joint and surrounding casings for use with the articulation section of  FIG.  1   ; 
         FIG.  6 A  is a side view of the articulation section and ball joint shown in a non-articulated configuration; and 
         FIG.  6 B  is a side view of the articulation section and ball joint shown in an articulated configuration. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS.  1  and  2   , a surgical instrument  10  provided in accordance with the present disclosure generally includes a housing  20 , a shaft  30  extending distally from housing  20 , an end effector assembly  40  extending distally from shaft  30 , and an actuation assembly  100  (shown in phantom in  FIG.  1   ) disposed within housing  20  and operably associated with shaft  30  and end effector assembly  40 . Instrument  10  is detailed herein as an articulating electrosurgical forceps configured for use with a robotic surgical system, e.g., robotic surgical system  500  ( FIG.  3   ). However, the aspects and features of instrument  10  provided in accordance with the present disclosure, detailed below, are equally applicable for use with other suitable surgical instruments (including non-robotic surgical instrument) and/or in other suitable surgical systems (including non-robotic surgical systems). 
     Housing  20  of instrument  10  includes first and second body portion  22   a,    22   b  and a proximal face plate  24  ( FIG.  2   ) that cooperate to enclose actuation assembly  100  therein. Proximal face plate  24  includes apertures defined therein through which inputs  110 - 140  of actuation assembly  100  extend. A pair of latch levers  26  (only one of which is illustrated in  FIG.  1   ) extend outwardly from opposing sides of housing  20  and enables releasable engagement (directly or indirectly) of housing  20  with a robotic arm of a surgical system, e.g., robotic surgical system  500  ( FIG.  3   ). An aperture  28  defined through housing  20  permits thumbwheel  440  to extend therethrough to enable manual manipulation of thumbwheel  440  from the exterior of housing  20  to permit manual opening and closing of end effector assembly  40 . 
     Shaft  30  of instrument  10  includes a distal segment  32 , a proximal segment  34 , and an articulating section  600  disposed between the distal and proximal segments  32 ,  34 , respectively. Articulating section  600  includes one or more articulating components  610 , e.g., links, joints, etc. A plurality of articulation cables  38   a - 38   d,  e.g., four (4) articulation cables, or other suitable actuators, extends through articulating section  600 . More specifically, articulation cables  38   a - 38   d  are operably coupled to distal segment  32  of shaft  30  at the distal ends thereof and extend proximally from distal segment  32  of shaft  30 , through articulating section  600  of shaft  30  and proximal segment  34  of shaft  30 , and into housing  20 , wherein articulation cables  38   a - 38   d  operably couple with an articulation assembly  200  of actuation assembly  100  to enable selective articulation of distal segment  32  (and, thus end effector assembly  40 ) relative to proximal segment  34  and housing  20 , e.g., about at least two axes of articulation (yaw and pitch articulation, for example). Articulation cables  38   a - 38   d  are arranged in a generally rectangular configuration, although other suitable configurations are also contemplated. 
     With respect to articulation of end effector assembly  40  relative to proximal segment  34  of shaft  30 , actuation of articulation cables  38   a - 38   d  is effected in pairs. More specifically, in order to pitch end effector assembly  40 , the upper pair of cables  38   a,    38   d  is actuated in a similar manner while the lower pair of cables  38   b,    38   c  is actuated in a similar manner relative to one another but an opposite manner relative to the upper pair of cables  38   a,    38   b.  With respect to yaw articulation, the right pair of cables  38   a,    38   b  is actuated in a similar manner while the left pair of cables  38   c,    38   d  is actuated in a similar manner relative to one another but an opposite manner relative to the right pair of cables  38   a,    38   b.    
     Distal segment  32  of shaft  30  defines a clevis portion of end effector assembly  40  that supports first and second jaw members  42 ,  44 , respectively. Each jaw member  42 ,  44  includes a proximal extension portion  43   a,    45   a  and a distal body portion  43   b,    45   b,  respectively. Distal body portions  43   b,    45   b  define opposed tissue-contacting surfaces  46 ,  48 , respectively. Proximal extension portions  43   a,    45   a  are pivotably coupled to one another about a pivot pin  50  and are operably coupled to one another via a cam drive mechanism  52  (described in greater detail below) to enable pivoting of jaw member  42  relative to jaw member  44  and distal segment  32  of shaft  30  between a spaced-apart position (e.g., an open position of end effector assembly  40 ) and an approximated position (e.g., a closed position of end effector assembly  40 ) for grasping tissue between tissue-contacting surfaces  46 ,  48 . As an alternative to this unilateral configuration, a bilateral configuration may be provided whereby both jaw members  42 ,  44  are pivotable relative to one another and distal segment  32  of shaft  30 . 
     A translating cutting element (not shown) is provided and selectively advanceable to enable cutting of tissue grasped between tissue-contacting surfaces  46 ,  48  of jaw members  42 ,  44 , respectively. A cutting drive assembly  300  of actuation assembly  100  provides for selective actuation of a cutting rod  490  which, in turn, translates the cutting element to cut tissue grasped between tissue-contacting surfaces  46 ,  48 . Cutting drive assembly  300  is operably coupled to third input  130  of actuation assembly  100  such that, upon receipt of appropriate rotational input into third input  130 , cutting drive assembly  300  advances the cutting rod  490  to translate the cutting element between jaw members  42 ,  44  to cut tissue grasped between tissue-contacting surfaces  46 ,  48 . 
     Continuing with reference to  FIGS.  1  and  2   , a drive rod  484  ( FIG.  4   ) of cam drive mechanism  52  is operably coupled to end effector assembly  40  such that longitudinal actuation of drive rod  484  pivots jaw member  42  relative to jaw member  44  between the spaced-apart and approximated positions, as detailed below. More specifically, urging drive rod  484  proximally pivots jaw member  42  relative to jaw member  44  towards the approximated position while urging drive rod  484  distally pivots jaw member  42  relative to jaw member  44  towards the spaced-apart position. However, the reverse configuration is also contemplated. Drive rod  484  extends proximally from end effector assembly  40  through shaft  30  and into housing  20  wherein drive rod  484  is operably coupled with a jaw drive assembly  400  of actuation assembly  100  to enable selective actuation of end effector assembly  40  to grasp tissue therebetween and apply a closure force within an appropriate jaw closure force range, e.g., in response to an appropriate rotational input into fourth input  140 . 
     Tissue-contacting surfaces  46 ,  48  of jaw members  42 ,  44 , respectively, are at least partially formed from an electrically conductive material and are energizable to different potentials to enable the conduction of electrical energy through tissue grasped therebetween, although tissue-contacting surfaces  46 ,  48  may alternatively be configured to supply any suitable energy, e.g., thermal, microwave, light, ultrasonic, etc., through tissue grasped therebetween for energy-based tissue treatment. Instrument  10  defines conductive pathways extending through housing  20  and shaft  30  to end effector assembly  40  that may include lead wires, contacts, and/or electrically-conductive components to enable electrical connection of tissue-contacting surfaces  46 ,  48  of jaw members  42 ,  44 , respectively, to an energy source (not shown), e.g., an electrosurgical generator via an electrosurgical cable extending therebetween, for supplying energy to tissue-contacting surfaces  46 ,  48  to treat, e.g., seal, tissue grasped between tissue-contacting surfaces  46 ,  48 . The electrically conductive pathways to tissue-contacting surfaces  46 ,  48  of jaw members  42 ,  44 , are illustrated, for example, as respective first and second lead wires  85   a,    85   b  ( FIG.  4   ). 
     Actuation assembly  100  is disposed within housing  20  and includes articulation assembly  200 , cutting drive assembly  300 , and jaw drive assembly  400 . Articulation assembly  200  is operably coupled between first and second inputs  110 ,  120 , respectively, of actuation assembly  100  and articulation cables  38  such that, upon receipt of appropriate rotational inputs into first and/or second inputs  110 ,  120 , articulation assembly  200  manipulates cables  38  ( FIG.  1   ) to articulate end effector assembly  40  in a desired direction, e.g., to pitch and/or yaw end effector assembly  40 . Cutting drive assembly  300 , as noted above, enables reciprocation of the cutting element (not shown) between jaw members  42 ,  44  to cut tissue grasped between tissue-contacting surfaces  46 ,  48  in response to receipt of appropriate rotational input into third input  130 . Jaw drive assembly  400  is operably coupled between fourth input  140  of actuation assembly  100  and drive rod  484  such that, upon receipt of appropriate rotational input into fourth input  140 , jaw drive assembly  400  pivots jaw members  42 ,  44  between the spaced-apart and approximated positions to grasp tissue therebetween and apply a closure force within an appropriate closure force range. 
     Actuation assembly  100  is configured to operably interface with a robotic surgical system  500  ( FIG.  3   ) when instrument  10  is mounted on robotic surgical system  500 , to enable robotic operation of actuation assembly  100  to provide the above-detailed functionality. That is, robotic surgical system  500  selectively provides rotational inputs to inputs  110 - 140  of actuation assembly  100  to articulate end effector assembly  40 , grasp tissue between jaw members  42 ,  44 , and/or cut tissue grasped between jaw members  42 ,  44 . However, it is also contemplated that actuation assembly  100  be configured to interface with any other suitable surgical system, e.g., a manual surgical handle, a powered surgical handle, etc. For the purposes herein, robotic surgical system  500  is generally described. 
     Robotic surgical system  500  is configured for use in accordance with the present disclosure. Aspects and features of robotic surgical system  500  not germane to the understanding of the present disclosure are omitted to avoid obscuring the aspects and features of the present disclosure in unnecessary detail. 
     Robotic surgical system  500  generally includes a plurality of robot arms  502 ,  503 ; a control device  504 ; and an operating console  505  coupled with control device  504 . Operating console  505  may include a display device  506 , which may be set up in particular to display three-dimensional images; and manual input devices  507 ,  508 , by means of which a person, e.g., a surgeon, may be able to telemanipulate robot arms  502 ,  503  in a first operating mode. Robotic surgical system  500  may be configured for use on a patient  513  lying on a patient table  512  to be treated in a minimally invasive manner. Robotic surgical system  500  may further include a database  514 , in particular coupled to control device  504 , in which are stored, for example, pre-operative data from patient  513  and/or anatomical atlases. 
     Each of the robot arms  502 ,  503  may include a plurality of members, which are connected through joints, and a mounted device which may be, for example, a surgical tool “ST.” One or more of the surgical tools “ST” may be instrument  10  ( FIG.  1   ), thus providing such functionality on a robotic surgical system  500 . 
     Robot arms  502 ,  503  may be driven by electric drives, e.g., motors, connected to control device  504 . Control device  504 , e.g., a computer, may be configured to activate the motors, in particular by means of a computer program, in such a way that robot arms  502 ,  503 , and, thus, their mounted surgical tools “ST” execute a desired movement and/or function according to a corresponding input from manual input devices  507 ,  508 , respectively. Control device  504  may also be configured in such a way that it regulates the movement of robot arms  502 ,  503  and/or of the motors. 
     Turning now to  FIGS.  4 - 6 B , the articulation section  600  and the various components associated therewith are depicted in further detail. More particularly, articulation section  600  includes a ball joint  610  and a pair of opposing casings  620   a  and  620   b  that are configured to, upon assembly, encase ball joint  610  at least partially therein ( FIG.  6 A- 6 B ). Ball joint  610  seats within opposing chamfers  621   a,    621   b  defined in respective casings  620   a,    620   b  such that the ball joint  610  is freely rotatable, e.g., articulatable, therein. Articulation cables, e.g., cables  38   a - 38   d,  feed through the ball joint  610  as described below. 
     Ball joint  610  includes one or more spherical segments  610   a - 610   d  which, together, make of the outer surface of the ball joint  610  and which are configured to rotationally seat within the respective interfaces or chamfers  621   a,    621   b  defined in casings  620   a,    620   b.  Although referred to herein as chamfers  621   a,    621   b,  other interfaces are envisioned, e.g., spherical interfaces. Cable guide channels are defined between each respective pair of the segments, e.g., channel  611   a  defined between segments  610   a,    610   d,  channel  611   b  defined between segments  610   a,    610   b,  channel  611   c  a defined between segments  610   b,    610   c,  and channel  611   d  defined between segments  610   c,    610   d.  Each channel, e.g.,  611   a,  is configured to receive a corresponding articulation cable, e.g., cable  38   a,  therein such that, as described in detail above, each opposing cable pair, e.g., cables  38   a,    38   c,  may slide in opposite directions within its respective channel  611   a,    611   c  to articulate the ball joint  610  and corresponding distal segment  32  of the shaft  30  in a given direction. 
     Each casing  620   a,    620   b,  includes apertures defined therein configured to correspondingly receive respective cables therethrough, e.g., cable  38   a  is configured to feed through aperture  623   a  defined in casing  620   b,  then through channel  611   a  in ball joint  610 , then through aperture  622   a  in casing  620   a,  cable  38   b  is configured to feed through aperture  623   b  defined in casing  620   b,  then through channel  611   b  in ball joint  610 , then through aperture  622   b  in casing  620   a,  etc. 
     An angled surface is defined on each respective side of each channel in communication with the same, e.g., angled surface  612   a  is defined on each side of channel  611   a,  angled surface  612   b  is defined on each side of channel  611   b,  angled surface  612   c  is defined on each side of channel  611   c,  and angled surface  612   d  is defined on each side of channel  611   d.  Angled surfaces, e.g., angled surface  612   a,  are each configured to allow respective cables, e.g., cable  38   a,  to angle from a substantially straight or in-line orientation ( FIG.  6 A ) to an angled orientation ( FIG.  6 B ) to articulate (pitch and yaw) distal segment  32  at a desired angle a ( FIG.  6 B ). Angled surfaces  612   a - 612   d  facilitate cable  38   a - 38   d  length changes and guide the cables  38   a - 38   d  through a smooth and gradual arc-like transition between casings  620   a,    620   b.  Angle a may range from about zero degrees (0°) to about sixty degrees (60°) depending upon a particular purpose. Other ball joints  610  may be utilized that have greater articulation angles. Alternatively, multiple ball joints  610  may be utilized for higher angles in a compounding fashion 
     As can be appreciated, designing the articulation section  600  with a single ball joint  610  capable of articulating sixty degrees (60°) in any direction simplifies the overall design and decreases overall surgical instrument expense. Moreover, a shaft  30  having a single ball joint  610  facilitates smoother articulation as the shaft  30  articulates about a single articulation plane. Casings  620   a,    620   b  may be configured to contact one another at full articulation in any one direction along the articulation plane and, as such, act as a hard stop to the desire articulation angle, e.g., sixty degrees (60°). The casings  620   a,    620   b  may be dimensioned to accommodate any maximum angle or hard stop. 
     As can be appreciated, when the cables  38   a - 38   d  are translated to articulate the distal segment  32  and held taught, the four (4) cables  38   a - 38   d  act as an anti-rotation feature and prevent unintended rotation of the distal segment  32  (and ball joint  610 ). This allows for more accurate and precise control of the distal segment  32  and, in turn, the end effector assembly  40 . 
     Ball joint  610  also includes a central aperture  625  defined therethrough configured to route and guide the cutting rod  490 , drive rod  484  and lead wires  85   a,    85   b  centrally therethrough in such a manner so as not to be affected by articulation of the distal segment  32 . The distal ends of the spherical segments  610   a - 610   d  may converge toward the central aperture  625  creating a cover-like appearance when viewed from the distal end. One or more portions of the clover-like central aperture  625  along with the distal ends of the spherical segments  610   a - 610   d  may be configured to guide or house one or more respective internal components therein. 
     It will be understood that various modifications may be made to the aspects and features disclosed herein. For example and as mentioned above, various electromechanical surgical instruments and/or electrosurgical instruments may be configured to be detachably couplable and controllable by a robotic surgical system. One exemplary robotic surgical system may generally include a plurality of surgical robotic arms each having an instrument drive unit with one or more electromechanical surgical instruments and/or electrosurgical instruments removably attached thereto; a control device; and an operating console coupled with the control device. 
     The operating console includes a display device, which is set up in particular to display three-dimensional images; and manual input devices by means of which a person, for example, a surgeon, is able to telemanipulate the robotic arms in a first operating mode, as known in principle to a person skilled in the art. Each of the robotic arms may be composed of a plurality of members, which are connected through joints. The robotic arms may be driven by electric drives that are connected to the control device. The control device (e.g., a computer) is set up to activate the drives, in particular by means of a computer program, in such a way that the robotic arms, the attached instrument drive units, and thus the various electromechanical surgical instruments and/or electrosurgical instruments execute a desired movement according to a movement defined by means of the manual input devices. The control device may also be set up in such a way that it regulates the movement of the robotic arms and/or of the drives. 
     The robotic surgical system is configured for use on a patient lying on a surgical table to be treated in a minimally invasive manner by means of the various electromechanical surgical instruments and/or electrosurgical instruments. The robotic surgical system may also include more than two robotic arms, the additional robotic arms likewise being connected to the control device and being telemanipulatable by means of the operating console. The various electromechanical surgical instruments and/or electrosurgical instruments may also be attached to the additional robotic arm. 
     The control device may control a plurality of motors, with each motor configured to drive movement of the robotic arms in a plurality of directions. Further, the control device may control the activation of the instrument drive unit to drive various operations of the various electromechanical surgical instruments and/or electrosurgical instruments, and may control a rotation of an internal motor pack of the instrument drive unit to ultimately rotate the various electromechanical surgical instruments and/or electrosurgical instruments about a longitudinal axis thereof. 
     The robotic surgical system may further include a surgical instrument holder configured to be coupled with or to the robotic arm. The surgical instrument holder holds the instrument drive unit and the various electromechanical surgical instruments and/or electrosurgical instruments. The surgical instrument holder supports or houses a motor, which receives controls and power from the control device to effect a rotation of an internal motor pack of the instrument drive unit, which results in a rotation of the various electromechanical surgical instruments and/or electrosurgical instruments about a longitudinal axis thereof. The surgical instrument holder may be slidably mounted onto a rail of the robotic arm and moved along the rail via a motor driven chain or belt or the like to adjust a position of the various electromechanical surgical instruments and/or electrosurgical instruments. 
     For a detailed description of the construction and operation of a robotic surgical system, reference may be made to U.S. Patent Application Publication No. 2012/0116416, filed on Nov. 3, 2011, entitled “Medical Workstation,” the entire contents of which are incorporated by reference herein. 
     Therefore, the above description should not be construed as limiting, but merely as exemplifications of various aspects and features. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended thereto.