Patent Publication Number: US-2021169475-A1

Title: Articulating mechanism for surgical instrument

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of and priority to U.S. Provisional Patent Application No. 62/944,745 filed Dec. 6, 2019, the entire disclosure of which is incorporated by reference herein. 
    
    
     FIELD 
     The disclosure relates to surgical devices and, more particularly, to surgical devices that can be articulated. 
     BACKGROUND 
     Surgical instruments are known in the art which can be articulated at angles up to approximately 45 degrees and even greater angles. However, such instruments may require complex operating mechanisms to achieve articulation. 
     SUMMARY 
     The disclosure provides significant and non-obvious advantages over the prior art by enabling articulation over large angles between an endoscopic body portion and a tool assembly such as an anvil and cartridge assembly, thereby enabling significant extension of surgical operating procedural capabilities. 
     In one aspect, the disclosure relates to a surgical instrument including an endoscopic body portion defining a first longitudinal axis and having a proximal end portion and a distal end portion and a tool assembly defining a second longitudinal axis and having a proximal end portion and a distal end portion. The tool assembly is coupled to the endoscopic body portion at an interface connection. The interface connection includes a first angled surface formed on the distal end portion of the endoscopic body portion and a second angled surface formed on the proximal end portion of the tool assembly. The first and second angled surfaces are positioned in abutting relation. 
     The surgical instrument also includes an operating mechanism configured to transition the tool assembly from a first position in which the first and second axes are aligned to second articulated positions in which the first and second axes are misaligned, the operating mechanism including a drive member that extends through the endoscopic body portion and is coupled to the tool assembly such that rotation of the drive member causes rotation of the tool assembly in relation to the endoscopic body portion to transition the tool assembly from the first position to the second articulated positions. 
     In one aspect, the tool assembly includes a clamp member and the drive member is formed from a resilient material that is rigidly connected to the clamp member within the tool assembly such that actuation of the operating mechanism causes the clamp member to rotate the tool assembly around the interface connection of the endoscopic body portion. 
     In another aspect, the operating mechanism includes a rack and pinion gear assembly in operable communication with the drive member, the rack and pinion gear assembly including a rack and a pinion gear engaged with the rack, the pinion gear coupled to the drive member, wherein linear motion of the rack effects rotational movement of the pinion gear to effect corresponding rotation of the drive member. 
     In yet another aspect, the pinion gear of the rack and pinion gear assembly defines an aperture, the drive member being longitudinally movable through the aperture to facilitate longitudinal movement of the clamp member in relation to the tool assembly. 
     In one aspect, the first angled surface defines a first angle at the distal end portion of the endoscopic body portion, the second angled surface defines a second angle at the proximal end portion of the tool assembly, and the sum of the first angle and the second angle forms a third angle that is greater than or equal to 90 degrees. 
     In another aspect, the first angled surface defines a first angle at the distal end portion of the endoscopic body portion, the second angled surface defines a second angle at the proximal end portion of the tool assembly, and the sum of the first angle and the second angle forms a third angle that is less than 90 degrees. 
     In yet another aspect, the tool assembly includes an anvil and cartridge assembly, the anvil and cartridge assembly including a cartridge assembly and an anvil, the anvil and cartridge assembly being pivotably movable to effect the transitioning of the tool assembly from the first position to the second articulated positions. 
     In another aspect, the disclosure relates also to a surgical instrument wherein the tool assembly includes a cartridge assembly and an anvil. The cartridge assembly is pivotably movable in relation to the anvil between spaced and approximated positions. 
     The surgical instrument also includes an endoscopic body portion. The anvil and cartridge assembly and the endoscopic body portion each define respective longitudinal centerline axes and including proximal and distal end portions. The anvil and cartridge assembly are coupled to the endoscopic body portion at an interface connection. The interface connection includes a first angled surface formed on the distal end portion of the endoscopic body portion and a second angled surface formed on the proximal end portion of the anvil and cartridge assembly. The first and second angled surfaces are positioned in abutting relation. 
     The surgical instrument also includes an operating mechanism configured to transition the anvil and cartridge assembly from a first position in which the first longitudinal axis defined by the endoscopic body portion and the second longitudinal axis defined by the anvil and cartridge assembly are aligned to second articulated positions in which the first longitudinal axis defined by the endoscopic body portion and the second longitudinal axis defined by the anvil and cartridge assembly are misaligned. The operating mechanism includes a drive member that extends through the endoscopic body portion and is coupled to the anvil and cartridge assembly such that rotation of the drive member causes rotation of the anvil and cartridge assembly in relation to the endoscopic body portion to transition the anvil and cartridge assembly from the first position to the second articulated positions. 
     In an aspect, the surgical instrument again further includes a clamp member and the drive member is formed from a resilient material that is rigidly connected to the clamp member within the anvil and cartridge assembly such that actuation of the operating mechanism causes the clamp member to rotate the anvil and cartridge assembly around the interface connection of the endoscopic body portion. 
     In an aspect, again the operating mechanism includes a rack and pinion gear assembly in operable communication with the drive member, the rack and pinion gear assembly including a rack and a pinion gear engaged with the rack, the pinion gear coupled to the drive member, wherein linear motion of the rack effects rotational movement of the pinion gear to effect corresponding rotation of the drive member. 
     In an aspect, again the pinion gear of the rack and pinion gear assembly defines an aperture, the drive member being longitudinally movable through the aperture to facilitate longitudinal movement of the clamp member in relation to the tool assembly. 
     In an aspect, again the first angled surface defines a first angle at the distal end portion of the endoscopic body portion, the second angled surface defines a second angle at the proximal end portion of the tool assembly, and the sum of the first angle and the second angle forms a third angle that is greater than or equal to 90 degrees. 
     In an aspect, again the first angled surface may define a first angle at the distal end portion of the endoscopic body portion, the second angled surface defines a second angle at the proximal end portion of the tool assembly, and the sum of the first angle and the second angle forms a third angle that is less than 90 degrees. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate aspects of the disclosure and, together with the detailed description of the aspects of the disclosure given below, serve to explain the principles of the disclosure: 
         FIG. 1  illustrates a perspective view of a distal portion of a surgical instrument exemplified by a stapling device according to aspects of the disclosure including an endoscopic body portion and a tool assembly configured for a stapling device and therefore having an anvil assembly and a cartridge assembly or anvil and cartridge assembly with the tool assembly in an open, non-articulated position aligned with the longitudinal axis of the endoscopic body portion; 
         FIG. 2  is a perspective view of the endoscopic body portion and tool assembly shown in  FIG. 1  with the tool assembly in an articulated position at a first angle with respect to the longitudinal axis of the endoscopic body portion; 
         FIG. 3  is a perspective view of the endoscopic body portion and tool assembly shown in  FIG. 2  with the tool assembly in an articulated position at a 90 degree angle with respect to the longitudinal axis of the endoscopic body portion: 
         FIG. 4  is a perspective view of a portion of the stapling device shown in  FIG. 1  with a distal end of the endoscopic body portion separated from a proximal end of the tool assembly; 
         FIG. 5  is a cross sectional view of an interface connection between the endoscopic body portion and the tool assembly shown in  FIG. 1  with the tool assembly in a non-articulated position; and 
         FIG. 6  is a cross sectional view of the endoscopic body portion and the tool assembly shown in  FIG. 1  in the articulated position shown in  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the disclosure relate to connection and transfer devices that provide significant and non-obvious advantages in the field of surgical devices by enabling articulation between an endoscopic body portion and a tool assembly over large arc segments with a simple articulation mechanism that does not require longitudinal movement of an articulation link, thereby enabling significant extension of surgical operating procedural capabilities. 
     Throughout this description, the term “proximal” refers to the portion of the device closest to the operator and the term “distal” refers to the portion of the device furthest from the operator. 
     The disclosure relates to surgical instruments, for example, a surgical fastener applying apparatus such as disclosed in U.S. Pat. No. 8,292,156 B2 to Kostrzewski. The surgical instrument according to aspects of the disclosure includes a tool assembly, an endoscopic body portion, and an articulation mechanism that articulates the tool assembly in relation to the endoscopic body portion over large arc segments while providing simple operating components. Thus, the range of operation of the surgical instrument and the types of surgical activities that can be performed by the surgeon can be expanded without at the same time requiring complex operating components. 
       FIGS. 1-6  illustrate a surgical instrument including an articulation mechanism according to aspects of the disclosure.  FIG. 1  illustrates a perspective view of a portion of a surgical instrument  100 . The surgical instrument  100  has an endoscopic body portion  110  and a tool assembly  108  according to the aspects of the disclosure with the tool assembly  108  in a spaced apart position and extending linearly along a longitudinal axis X 1 -X 2  of the endoscopic body portion  110  of the surgical instrument  100 . In aspects of the disclosure, the tool assembly  108  is exemplified by an anvil and cartridge assembly of a surgical fastener applying apparatus or stapling device. Alternately, the tool assembly  108  may be in the form of a variety of other surgical devices including graspers, clip appliers, retractors, ligation devices, dissectors, or the like. 
     The tool assembly  108  includes a cartridge  1601  that is operably connected to an anvil  1602  and is movable in relation to the anvil  1602  between a spaced apart position ( FIG. 1 ) and a clamped or closed position (not shown). 
     The endoscopic body portion  110  includes a proximal end  110   a  ( FIG. 1 ) (represented by the break line) and a distal end  110   b  while the tool assembly  108  as exemplified by the anvil and cartridge assembly  160  includes a proximal end  160   a  and a distal end  160   b.  Axis portion X 1  of the axis X 1 -X 2  extends from proximal end  110   a  of the endoscopic body portion  110  to the distal end  110   b  of the endoscopic body portion  110  while axis portion X 2  of the axis X 1 -X 2  extends from the distal end  110   b  of the endoscopic body portion  110 . 
     The tool assembly  108  defines a longitudinal axis Y 1 -Y 2  wherein axis portion Y 1  ranges from an orientation overlapping axis portion X 1  to form an angle θ 1  between axis portion X 1  and axis portion Y 1  equal to zero, as in  FIG. 1 , to an orientation defining an angle of 90 degrees or more as shown in  FIG. 6  with axis X 1  as described below. 
       FIG. 2  is a perspective view of the endoscopic body portion  110  and the tool assembly  108  as shown in  FIG. 1  with respect to the longitudinal centerline axis X 1 -X 2  of the endoscopic body portion  110  and illustrating one aspect of an operating mechanism  120  for articulation of the tool assembly  108  with respect to the longitudinal centerline axis X 1 -X 2  of the endoscopic body portion  110 . The tool assembly  108  defines a longitudinal centerline axis Y 1 -Y 2 . More particularly, the tool assembly  108  now extends at angle θ 2  ( FIG. 2 ) between axis portion X 2  and axis portion Y 2 . Angle θ 1  between axis portion X 1  and axis portion Y 1  is shown and is an acute angle equal to angle θ 2 . 
     The distal end  110   b  of the endoscopic body portion  110  and the proximal end  160   a  of the tool assembly  108 —are configured to interface with one another as further described below. 
     The operating mechanism  120  includes a rack and pinion gear assembly  122  in operable communication with a drive member  128  wherein linear motion of rack  124  in a direction transverse to the axis X 1 -X 2  effects rotational movement of pinion gear  126  by the intermeshing of rack gear teeth  124 ′ with gear teeth  126 ′. The reversible linear motion of the rack  124  as shown by double-sided arrow R rotates the pinion gear  126 , as shown by double sided curved arrow G, which is operably connected to the drive member  128  causing thereby the rotation and flexing of the drive member  128 . 
       FIGS. 4-6  illustrate the interconnection of the elongate body  110  and the tool assembly  108 . The drive member  128  is operably connected to a clamp member  168  of cartridge assembly  1601  (see  FIG. 1 ). Cartridge assembly  1601  includes a longitudinal slot  161  which receives and confines the clamp member  168 . The clamp member  168  is confined within the tool assembly  108  as is known in the art. 
     As the clamp member  168  is rotated by the drive member  128 , the cartridge assembly  1601  is forced to rotate around interface connection  130  which is shown and described in more detail below in  FIG. 4 . The rotation of the clamp member  168  which is confined within the tool assembly  108  causes rotation of the entire tool assembly  108  around the interface connection  130 . 
     Referring again to  FIG. 2 , drive member  128  includes a portion  128 ′ extending along or parallel to longitudinal centerline axis X 1 -X 2  having a square or rectangular cross-section to define four flat surfaces around the longitudinal centerline axis X 1 -X 2 . The portion  128 ′ of drive member  128  is received in aperture  1260  of gear  126  in a slidable manner to enable the drive member  128  to advance and retract longitudinally in relation to the gear  126  along or parallel to the longitudinal centerline axis X 1 -X 2  in the direction of double-sided arrow A. The advancing and retracting of the drive member  128  enables longitudinal movement of the clamp member  169  within the tool assembly  108  to facilitate actuation of the tool assembly  108 , e.g., stapling and cutting of tissue. 
       FIG. 3  is a perspective view of the tool assembly  108  as shown in  FIG. 2  with longitudinal centerline axis Y 1 -Y 2  of the tool assembly  108  extending at a 90 degree angle with respect to the longitudinal axis X 1 -X 2  of the endoscopic body portion  110 . In this position, angle θ 1  between axis portion X 1  and axis portion Y 1  is equal to angle θ 2 , the angle between axis portion X 2  and axis portion Y 2  and both are equal to 90 degrees in  FIG. 3 . 
     As explained below with respect to  FIG. 4 , angle α 3  is the angle between the longitudinal centerline axis X 1 -X 2  and the longitudinal centerline axis Y 1 -Y 2  and is equal to the sum of angles α 1  and α 2  which are further described and defined with respect to  FIGS. 4-6  below. Since the angle α 3  and the angle θ 1  are defined with respect to the axes X 1 -X 2  and Y 1 -Y 2 , the sum of angles α 3  and θ 1  equals 180 degrees. 
       FIG. 4  is a perspective view of the stapling device  100  wherein the endoscopic body portion  110  and the tool assembly  108  are separated from one another showing the internal structure of the interface connection  130  that is configured to enable the endoscopic body portion  110  and the tool assembly  108  to engage and articulate in relation to one another. The interface connection structure  114  of interface connection  130  is configured and disposed on an inclined or angled surface  112  at distal end  110   b  of the endoscopic body portion  110 . Since the endoscopic body portion  110  is illustrated as having a circular cross-section, the inclined surface  112  defines an ellipse having a major axis X 2 ′-X 2 ′. Angle α 1  is the angle between major axis X 2 ′-X 2 ′ and the longitudinal centerline axis X 1 -X 2  of the endoscopic body portion  110  and also represents the angle of the inclined surface  112  with respect to the longitudinal centerline axis X 1 -X 2 . 
     Similarly, since the proximal end  160   a  of the tool assembly  108  also has a circular cross-section, the interface connection  130  includes an inclined or angled surface  162  on the proximal end  160   a  of the tool assembly  108 . Inclined surface  162  also defines an ellipse having a major axis Y 1 ′-Y 1 ′ and angle α 2  is the angle between major axis Y 1 ′-Y 1 ′ and the longitudinal centerline axis Y 1 -Y 2  of the tool assembly  108  and also represents the angle of the inclined surface  162  with respect to the longitudinal centerline axis Y 1 -Y 2 . 
     An aperture  164  is defined in the inclined surface  162  which receives the interface connection structure  114  when the interface connection  130  is established. The interface structure  114  includes a circumferential groove  116  which engages a perimeter  166  of the aperture  164  and enables rotation of the tool assembly  108  around center X of aperture  118  that is defined by the interface connection structure  114  and is assumed to coincide with longitudinal centerline axis X 1 -X 2 . 
     Major axis X 2 ′-X 2 ′ coincides or aligns with major axis Y 1 ′-Y 1 ′ when angle θ 1  and angle θ 2  equal zero as shown in  FIG. 1  and when angle θ 1  and angle θ 2  equal 90 degrees as shown in  FIG. 3 . 
       FIG. 5  is a cross sectional view of interface connection  130  between the endoscopic body portion  110  and the tool assembly  108  when the angle θ 1  and angle θ 2  equal zero, which is also when the longitudinal centerline axis X 1 -X 2  of the endoscopic body portion  110  and the longitudinal centerline axis Y 1 -Y 2  of the tool assembly  108  are aligned and overlapping. In addition, the major axis X 2 ′-X 2 ′ of the endoscopic body portion  110  and the major axis Y 1 ′-Y 1 ′ of the tool assembly  108 —are also aligned. The apertures  118  and  164  are illustrated in cross-sectional view. 
       FIG. 6  is a cross sectional view of the endoscopic body portion  110  and the tool assembly  108  at a 90 degree angle (θ 1 =θ 2 =90 degrees and also α 3 =α 1 +α 2 =90 degrees) with respect to one another as shown in  FIG. 4  and illustrating operating mechanism drive member  128  within an interior volume of space  110 ′ of endoscopic body portion  110 . The drive member  128  enables rotation of the tool assembly  108 —around the interface connection  130  with respect to the endoscopic body portion  110 . 
     The connection  132  between the operating mechanism drive member  128  and the clamp member  168  for the tool assembly  108  as exemplified by the tool assembly  108  illustrates that rotation of the operating mechanism drive member  128  causes rotation of the clamp member  168 . Since the clamp member  168  is non-rotatably positioned within the tool assembly  108 , rotation of the clamp member  168  causes rotation of the tool assembly  108  around the interface connection  130 . The operating mechanism drive member  128  is composed of bendable material that is rigidly connected to the clamp member  168  in an interior portion  160 ′ of the tool assembly  108 . As such, when the drive member  128  is moved longitudinally in relation to the tool assembly  108  with the tool assembly  108  articulated in relation to the endoscopic body portion  110 , the drive member  128  will bend about the axis of articulation X 1 -X 2  such that angles θ 1  and θ 2  vary initially from zero to 90°. When θ 1  and θ 2  are 90°, the major axis X 2 ′-X 2 ′ of the endoscopic body portion  110  and the major axis Y 1 ′-Y 1 ′ of the tool assembly  108 —are also aligned as shown in  FIG. 6 . 
     In an aspect of the disclosure, not shown, surfaces  112  and  162  may be inclined at angles such that the third angle α 3 , which is equal to the sum of the first angle α 1  and the second angle α 2 , is less than 90 degrees, thereby enabling articulation of the tool assembly  108  over arc segments greater than 90 degrees. The portion of operating mechanism drive member  128  coinciding with axis Y 1 -Y 2  would also be further inclined with respect to the portion of operating mechanism drive member  128  coinciding with axis X 1 -X 2  to conform to the shape formed by the now acute angle α 3 . 
     For example, instead of being 45 degrees each, α 1  and α 2  may each be equal to 30 degrees so that α 3  now equals 60 degrees. Therefore, when the surfaces  112  and  162  are aligned as shown in  FIG. 6 , the angles θ 1 =θ 2  now equal 180 degrees minus α 3  or 120 degrees. 
     For other surgical instruments such as forceps, graspers, retractors, clip appliers, ligation devices, or the like, such devices also include endoscopic body portions and tool assemblies that are configured to provide the specific surgical function of the instrument. In such devices, the drive member  128  may have a distal end coupled to the tool assembly in a manner to facilitate rotation of the tool assembly in relation to the endoscopic body portion  110  since such a device may not include a clamp member such as described above. 
     In addition, it should be noted that while the endoscopic body portion  110  is illustrated in  FIGS. 1-6  as having a constant cross-sectional diameter from proximal end  110   a  to the interface connection  130  at distal end  110   b,  the endoscopic body portion  110  may be configured with a convex or concave flaring arrangement wherein the cross-sectional diameter varies along the longitudinal centerline axis X 1 -X 2  and in the vicinity of the interface connection  130 . The proximal end  160   a  of the tool assembly  108  may also be configured in a similar manner in the vicinity of the interface connection  130 . 
     In view of the foregoing description, referring to  FIGS. 1-6 , those skilled in the art will recognize and understand that surgical instrument  100  includes endoscopic body portion  110  defining first longitudinal axis X 1 -X 2  and having proximal end portion  110   a  and distal end portion  110   b  and tool assembly  108  defining second longitudinal axis Y 1 -Y 2  and having proximal end portion  160   a,  and distal end portion  160   b.  The tool assembly  108  is coupled to the endoscopic body portion  110  at interface connection  130 . The interface connection  130  includes a first angled surface, represented by inclined or angled surface  112  at distal end  110   b  of the endoscopic body portion  110 , and a second angled surface, represented by inclined or angled surface  162  at proximal end  160   a  of tool assembly  108 . The first and second angled surfaces  110   b  and  160   a,  respectively, are positioned in abutting relation. 
     The operating mechanism  120  is configured to transition the tool assembly  108  from a first position in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are aligned, as shown in  FIG. 1  and  FIG. 5 , to second articulated positions in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are misaligned, as shown in  FIGS. 2, 3, 4, and 6 . Referring most particularly to  FIGS. 2 and 6 , the operating mechanism  120  includes drive member  128  that extends through the endoscopic body portion  110  and is coupled to the tool assembly  108  such that rotation of the drive member  128  causes rotation of the tool assembly  108  in relation to the endoscopic body portion  110  to transition the tool assembly  108  from the first position to the second articulated positions. 
     The tool assembly  108  includes clamp member  168  and the drive member  128  is formed from a resilient material that is rigidly connected to the clamp member  168  within the tool assembly  108  such that actuation of the operating mechanism, or operating mechanism drive member  128 , causes the clamp member  168  to rotate the tool assembly  108  around the interface connection  130  of the endoscopic body portion  110 . 
     Referring most particularly to  FIG. 2 , in an aspect, the operating mechanism  120  includes rack and pinion gear assembly  122  that is in operable communication with the drive member  128 . The rack and pinion gear assembly  122  includes rack  124  and pinion gear  126  engaged with the rack  124 . The pinion gear  126  is coupled to the drive member  128 , wherein linear motion of the rack  124  effects rotational movement of the pinion gear  126  to effect corresponding rotation of the drive member  128 . 
     In an aspect, pinion gear  126  of the rack and pinion gear assembly  122  defines aperture  1260 . The drive member  128  is longitudinally movable through the aperture  1260  to facilitate longitudinal movement of the clamp member  168  in relation to the tool assembly  108 . 
     In an aspect, the first inclined or angled surface  112  defines the first angle α 1  at the distal end portion  110   b  of the endoscopic body portion  110  while the second inclined or angled surface  162  defines the second angle α 2  at the proximal end portion  160   a  of the tool assembly  108 , and the sum of the first angle α 1  and the second angle α 2  forms third angle α 3  that is greater than or equal to 90 degrees. 
     In an aspect, the first inclined or angled surface  112  defines the first angle α 1  at the distal end portion  110   b  of the endoscopic body portion  110  while the second inclined or angled surface  162  defines the second angle α 2  at the proximal end portion  160   a  of the tool assembly  108 , and the sum of the first angle α 1  and the second angle α 2  forms third angle α 3  that is less than 90 degrees. 
     In an aspect of the disclosure, the tool assembly  108  includes anvil and cartridge assembly  160 . The anvil and cartridge assembly  160  includes cartridge assembly  1601  and anvil  1602 . The anvil and cartridge assembly  160  is pivotably movable to effect the transitioning of the tool assembly  108  from the first position in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are aligned, as shown in  FIG. 1  and  FIG. 5 , to the second articulated positions in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are misaligned, as shown in  FIGS. 2, 3, 4, and 6 . 
     In one aspect of the disclosure, surgical instrument  100  includes cartridge assembly  1601  and anvil  1602 . The cartridge assembly  1601  is pivotably movable in relation to the anvil  1602  between spaced and approximated positions. 
     The surgical instrument  100  includes endoscopic body portion  110  and anvil and cartridge assembly  160  wherein the endoscopic body portion  110  and the anvil and cartridge assembly  160  each define respective first and second longitudinal centerline axes X 1 -X 2  and Y 1 -Y 2 , respectively, and include proximal end portions  110   a  and  160   a  and distal end portions  110   b  and  160   b,  respectively. The anvil and cartridge assembly  160  is coupled to the endoscopic body portion  110  at interface connection  130 . The interface connection  130  includes first inclined or angled surface  112  formed on the distal end portion  110   b  of the endoscopic body portion  110  and second inclined or angled surface  162  formed on the proximal end portion  160   a  of the anvil and cartridge assembly  160 . The first and second angled surfaces  112  and  162  are positioned in abutting relation. 
     The operating mechanism  120  is configured to transition the anvil and cartridge assembly  160  from the first position in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are aligned, as shown in  FIG. 1  and  FIG. 5 , to the second articulated positions in which the first and second axes X 1 -X 2  and Y 1 -Y 2 , respectively, are misaligned, as shown in  FIGS. 2, 3, 4, and 6 . 
     The operating mechanism  120  includes drive member  128  that extends through the endoscopic body portion  110  and is coupled to the anvil and cartridge assembly  160  such that rotation of the drive member  128  causes rotation of the anvil and cartridge assembly  160  in relation to the endoscopic body portion  110  to transition the anvil and cartridge assembly  160  from the first position to the second articulated positions, as indicated above. 
     In an aspect, the surgical instrument  100  also includes clamp member  168 , as shown in  FIG. 6 , and the drive member  128  is again formed from a resilient material that is rigidly connected to the clamp member  168  within the anvil and cartridge assembly  160  such that actuation of the operating mechanism  120  causes the clamp member  168  to rotate the anvil and cartridge assembly  160  around the interface connection  130  of the endoscopic body portion  110 . 
     In an aspect, the operating mechanism  120  also includes rack and pinion gear assembly  122  that is in operable communication with the drive member  128 . The rack and pinion gear assembly  122  includes rack  124  and pinion gear  126  engaged with the rack  124 . The pinion gear  126  is coupled to the drive member  128 , wherein linear motion of the rack  124  effects rotational movement of the pinion gear  126  to effect corresponding rotation of the drive member  128 . 
     In an aspect, pinion gear  126  of the rack and pinion gear assembly  122  also defines aperture  1260 . The drive member  128  is longitudinally movable through the aperture  1260  to facilitate longitudinal movement of the clamp member  168  in relation to the tool assembly  108 . 
     In an aspect, the first inclined or angled surface  112  also defines the first angle α 1  at the distal end portion  110   b  of the endoscopic body portion  110  while the second inclined or angled surface  162  defines the second angle α 2  at the proximal end portion  160   a  of the tool assembly  108 , and the sum of the first angle α 1  and the second angle α 2  forms third angle α 3  that is greater than or equal to 90 degrees. 
     In another aspect, the first inclined or angled surface  112  also defines the first angle α 1  at the distal end portion  110   b  of the endoscopic body portion  110  while the second inclined or angled surface  162  defines the second angle α 2  at the proximal end portion  160   a  of the tool assembly  108 , and the sum of the first angle α 1  and the second angle α 2  forms third angle α 3  that is less than 90 degrees. 
     While several aspects of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as examples of particular aspects of the disclosure. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. 
     Although the foregoing disclosure has been described in some detail by way of illustration and example, for purposes of clarity or understanding, it will be obvious that certain changes and modifications may be practiced within the scope of the appended claims.