Patent Publication Number: US-2023157721-A1

Title: Retention anchor for surgical access devices

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/795,809, filed Feb. 20, 2020, the entire contents of which are hereby incorporated by reference herein. 
    
    
     FIELD 
     The present disclosure relates generally to surgical access devices. In particular, the present disclosure relates to a retention anchor for fixing a surgical access device in tissue. 
     BACKGROUND 
     In minimally invasive surgical procedures, including endoscopic and laparoscopic surgeries, a surgical access device permits the introduction of a variety of surgical instruments into a body cavity or opening. A surgical access device (e.g., a cannula or an access port) is introduced through an opening in tissue (e.g., a naturally occurring orifice or an incision) to provide access to an underlying surgical site in the body. The opening is typically made using an obturator having a blunt or sharp tip that may be inserted through a passageway of the surgical access device. For example, a cannula has a tube of rigid material with a thin wall construction, through which an obturator may be passed. The obturator is utilized to penetrate a body wall, such as an abdominal wall, or to introduce the surgical access device through the body wall, and is then removed to permit introduction of surgical instruments through the surgical access device to perform the surgical procedure. 
     Minimally invasive surgical procedures, including both endoscopic and laparoscopic procedures, permit surgery to be performed on organs, tissues, and vessels far removed from an opening within the tissue. In laparoscopic procedures, the abdominal cavity is insufflated with an insufflation gas, e.g., CO 2 , to create a pneumoperitoneum thereby providing access to the underlying organs. A laparoscopic instrument is introduced through a cannula accessing the abdominal cavity to perform one or more surgical tasks. The cannula may incorporate a seal to establish a substantially fluid tight seal about the laparoscopic instrument to preserve the integrity of the pneumoperitoneum. The cannula, which is subjected to the pressurized environment, e.g., the pneumoperitoneum, may include an anchor mechanism to prevent the cannula from backing out of the opening in the abdominal wall, for example, during manipulation of the laparoscopic instrument within the cannula or withdrawal of the laparoscopic instrument therefrom. 
     SUMMARY 
     This disclosure generally relates to a retention anchor for securing a surgical access device within tissue. The retention anchor provides a counter force during insertion and/or articulation of surgical instruments through the surgical access device. In aspects in which the surgical access device includes an anchor mechanism, the retention anchor is utilized in conjunction with the anchor mechanism to limit longitudinal movement of the surgical access device relative to the tissue (e.g., retropulsion and over-insertion) during, for example, receipt, manipulation, and/or withdrawal of surgical instruments therethrough. 
     The retention anchor includes an annular body and a washer affixed to the annular body that is movable relative thereto. This design increases the usability of the retention anchor by maximizing the fixation force on a surgical access device and minimizing the force required to move the retention anchor relative to the surgical access device, and makes manufacturing and assembly easier. 
     In one aspect, the disclosure provides a surgical access assembly including a cannula and a retention anchor. The cannula includes an elongated shaft, and the retention anchor includes an annular body and a washer secured to the annular body. The annular body includes an inner side surface defining an opening therethrough, and the washer includes an inner terminal edge defining an opening defined therethrough that is aligned with the opening of the annular body. The elongated shaft of the cannula extends through the openings of the annular body and the washer. The washer is transitionable between a first configuration in which the inner terminal edge of the washer is coincident with or disposed radially outwardly of the inner side surface of the annular body so that the retention anchor is slidable along the elongated shaft, and a second configuration in which the inner terminal edge of the washer extends radially inwardly of the inner side surface of the annular body and engages the elongated shaft to fix the retention anchor to the elongated shaft. 
     The inner side surface of the annular body may frictionally engage the elongated shaft of the cannula. The inner side surface of the annular body may include ridges. 
     The annular body may include a proximally-facing surface, and the washer may be positioned adjacent to the proximally-facing surface. The washer may include an outer terminal edge affixed to the annular body. The proximally-facing surface of the annular body may define an annular recess therein and, when the washer is in second configuration, the washer may be disposed within the annular recess. 
     In some aspects, when the washer is in the first configuration, the washer has a convex shape and when the washer is in the second configuration, the washer has a concave shape. 
     The washer may be more rigid than the annular body. The washer may be formed from a metal and the annular body may be formed from a rubber. 
     In another aspect, the disclosure provides a retention anchor for a surgical access device including an annular body and a washer secured to the annular body. The annular body includes an inner side surface defining an opening therethrough, and the washer includes an inner terminal edge defining an opening defined therethrough that is aligned with the opening of the annular body. The washer is transitionable between a first configuration in which the inner terminal edge of the washer is coincident with or disposed radially outwardly of the inner side surface of the annular body, and a second configuration in which the inner terminal edge of the washer extends radially inwardly of the inner side surface of the annular body. 
     The inner side surface of the annular body may include ridges. 
     The annular body may include a proximally-facing surface, and the washer may be positioned adjacent to the proximally-facing surface. The washer may include an outer terminal edge affixed to the annular body. The proximally-facing surface of the annular body may define an annular recess therein and, when the washer is in second configuration, the washer may be disposed within the annular recess. 
     In some aspects, when the washer is in the first configuration, the washer has a convex shape and when the washer is in the second configuration, the washer has a concave shape. 
     The washer may be more rigid than the annular body. The washer may be formed from a metal and the annular body may be formed from a rubber. 
     In yet another aspect, a method of securing a surgical access device to tissue includes: positioning an elongated shaft of a cannula within tissue; sliding a retention anchor disposed on the elongated shaft of the cannula distally until the retention anchor abuts an outer surface of the tissue, the retention anchor including an annular body having an inner surface defining an opening therethrough and a washer secured to the annular body and having an inner terminal edge defining an opening therethrough that is aligned with the opening of the annular body, the elongated shaft of the cannula extending through the openings of the annular body and the washer, the washer disposed in a first configuration in which an inner terminal edge of the washer is coincident with or disposed radially outwardly of an inner surface of the annular body so that the retention anchor is slidable along the elongated shaft; and moving the washer of the retention anchor to a second configuration in which the inner terminal edge of the washer extends radially inwardly of the inner side surface of the annular body and engages the elongated shaft to fix the retention anchor to the elongated shaft. 
     Moving the washer may include pressing the washer into an annular recess defined in the annular body of the retention anchor. 
     The method may further include expanding an expandable anchor of the cannula against an inner surface of the tissue. 
     The details of one or more aspects of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the aspects described in this disclosure will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of a surgical access assembly including a cannula and a retention anchor in accordance with an aspect of the disclosure; 
         FIG.  2    is a perspective view of the retention anchor of the surgical access assembly of  FIG.  1   ; 
         FIG.  3    is cross-sectional view of the surgical access assembly of  FIG.  1   , taken along section line  3 - 3  of  FIG.  1   , shown with the retention anchor in a first configuration; 
         FIG.  4    is a cross-sectional view of the surgical access assembly of  FIG.  3   , shown with the retention anchor in a second configuration; and 
         FIG.  5    is a side view of the surgical access assembly of  FIG.  1   , shown disposed within tissue. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the disclosure are described hereinbelow with reference to the accompanying drawings; however, it is to be understood that the disclosed aspects are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure. 
     Like reference numerals refer to similar or identical elements throughout the description of the figures. Throughout this description, the term “proximal” refers to a portion of a structure, or component thereof, that is closer to a user, and the term “distal” refers to a portion of the structure, or component thereof, that is farther from the user. 
       FIG.  1    illustrates a surgical access system  1  including a surgical access device or cannula  10  and a retention anchor  20 . The cannula  10  generally includes an elongated shaft  12  supporting an instrument housing  14  on a proximal or first end portion  12   a  thereof and an expandable anchor  16  (e.g., an inflatable anchor, such as a balloon, or a contractable anchor, such as a collapsible flange) on a distal or second end portion  12   b  thereof. The expandable anchor  16  secures the cannula  10  against an inner surface of a body wall, such as an abdominal wall, as seen in  FIG.  5   . 
     The retention anchor  20  is supported on the elongated shaft  12  of the cannula  10 . The retention anchor  20  is releasably engageable with the elongated shaft  12 , and slidable therealong to adjust the position of the retention anchor  20  on the elongated shaft  12 . The retention anchor  20  secures the cannula  10  against an outer surface of the body wall and stabilizes the cannula  10  relative to the body wall. 
     Generally, the cannula  10  is employed during surgery (e.g., laparoscopic surgery) to access a surgical site and may, in various aspects, provide for the sealed insertion of surgical instruments into an insufflated body cavity, such as an abdominal cavity. The cannula  10  is usable with an obturator (not shown). The obturator generally includes an elongated body supporting a tip on a distal end thereof. The tip can have a bladed or non-bladed (e.g., blunt) penetrating distal end that can be used to incise or separate tissue of the body wall so that the cannula  10  can be introduced therethrough. The cannula  10  and the obturator may be capable of being selectively connected together. For example, the obturator may be inserted into and through the cannula  10  until a handle housing of the obturator engages, e.g., selectively locks into, the instrument housing  14  of the cannula  10 . In this initial position, the cannula  10  and the obturator, which together form a trocar assembly, are employed to tunnel through a body wall, e.g., an abdominal wall, either by making a new passage through the body wall or by passing through an existing opening through the body wall. Once the trocar assembly has tunneled through the body wall, the obturator is removed, leaving the cannula  10  in place, e.g., in an incision created by the trocar assembly. The instrument housing  14  of the cannula  10  may include an insufflation port  15  that provides insufflation fluid (e.g., gases) into the body cavity, seals and/or valves (not shown) that allows surgical instrument to be inserted into the body cavity while preventing the escape of the insufflation fluid therefrom, and an anchor inflation port  17  which is in fluid communication with the expandable anchor  16  to expand and/or contract the expandable anchor  16 . 
     For a detailed description of the structure and function of exemplary surgical access devices suitable for use with a retention anchor of the present disclosure, reference may be made to U.S. Pat. Nos. 7,691,089; 8,926,508; and 10,299,778, the entire contents of each of which are hereby incorporated by reference herein. 
     Turning now to  FIG.  2   , in conjunction with  FIG.  1   , the retention anchor  20  includes an annular body  22  having a first or proximally-facing surface  24 , a second or distally-facing surface  26 , an outer side surface  28 , and an inner side surface  30 . The outer and inner side surfaces  28 ,  30  extend between and interconnect the first and second surfaces  24 ,  26  and respectively define outer and inner terminal edges  28   a ,  30   a  of the retention anchor  20 . 
     The inner side surface  30  defines an opening  23  through the annular body  22  that is sized and shaped to accommodate the elongated shaft  12  of the cannula  10  in a friction fit manner. The inner side surface  30  of the annular body  22  includes ridges  32  extending into the opening  23  to enhance the grip of the annular body  22  about the elongated shaft  12  of the cannula  10  and to limit movement of the retention anchor  20  relative to the cannula  10 . It should be understood that in addition to or as an alternative to the ridges  32 , the inner side surface  30  of the annular body  22  may include protrusions, bumps, projections, or other textured finishes to aid in retaining the retention anchor  20  on the elongated shaft  12  of the cannula  10  while allowing movement of the annular body  22  relative to the elongated shaft  12 . 
     As shown in  FIGS.  3  and  4   , the annular body  22  includes an annular recess  25  defined in the first surface  24 . The annular recess  25  extends from the inner side surface  30  of the annular body  22  radially outwardly towards the outer side surface  28 , but is spaced inwardly of the outer terminal edge  28   a  such that the annular recess  25  extends across a majority of the first surface  24  (e.g., across more than about 50% of the surface area of the first surface  24  and, in some aspects, across more than 75% of the surface area of the first surface  24 ). The annular recess  25  is sized and shaped to retain a washer  34  therein. 
     The washer  34  is a thin, flat annular disk including an inner terminal edge  34   a  defining an opening  35  therethrough, and an outer terminal edge  34   b . The opening  35  is aligned with the opening  23  defined through the annular body  22  to accommodate the elongated shaft  12  of the cannula  10  therethrough. The washer  34  is positioned adjacent to the first surface  24  of the annular body  22  and is transitionable between a first or clearance configuration having a convex shape, as seen in  FIG.  3   , and a second or interference configuration having a concave shape, as seen in  FIG.  4   . 
     The annular body  22  of the retention anchor  20  is formed from a flexible material, such as rubber, plastic, or other suitable polymer (e.g., elastomers). The washer  34  is formed from a material that is more rigid than the annular body  22 , such as a metal (e.g., a thin sheet of metal). The washer  34  is affixed to the annular body  22  by over-molding or insert molding the annular body  22  to the washer  34  such that the outer terminal edge  34   b  of the washer  34  is retained within the annular body  22  to securely attach the washer  34  to the annular body  22 . The washer  34  is affixed to the annular body  22  only at the outer terminal edge  34   b  such that the inner terminal edge  34   a  is movable relative to the annular body  22 . 
     The washer  34  has an outwardly biased dome shape, as shown in  FIG.  3   , with the outer terminal edge  34   b  of the washer  34  disposed within the annular body  22  and the inner terminal edge  34   a  of the washer  34  extending upwardly away from the first surface  24  of the annular body  22 . In this first configuration, the washer  34  has a convex shape, and the inner terminal edge  34   a  of the washer  34  is coincident with or disposed radially outwardly of the inner side surface  30  of the annular body  22  so that only the annular body  22  is engaged with the elongated shaft  12  of the cannula  10  and the retention anchor  20  is free to slide along the elongated shaft  12 . 
     The washer  34  is transitionable to the second configuration, as shown in  FIG.  4   , by pressing the washer  34  towards the annular body  22 . Since the outer terminal edge  34   b  of the washer  34  is affixed to the annular body  22 , the inner terminal edge  34   a  of the washer  34  is moved downwardly into the annular recess  25  of the first surface  24  of the annular body  22 . In this second configuration, the washer  34  has a concave shape, and the inner terminal edge  34   a  of the washer  34  extends radially inwardly of the inner side surface  30  of the annular body  22  and engages the elongated shaft  12  of the cannula  10  thereby fixing the retention anchor  20  to the elongated shaft  12  (e.g., locking the retention anchor  20  onto the cannula  10  by friction fit). 
       FIG.  5    illustrates the surgical access assembly  1  disposed within tissue “T,” e.g., an abdominal wall. The retention anchor  20  is secured to the cannula  10  prior to introducing the cannula  10  into the tissue “T” (e.g., the retention anchor  20  may be pre-installed on the cannula  10  during manufacture or may be placed on the cannula  10  prior to use in the operating room). The elongated shaft  12  of the cannula  10  is received through the tissue “T” (e.g., by utilizing an obturator (not shown) to facilitate entry of the cannula  10  through the tissue “T”), and the expandable anchor  16  is inflated within a body cavity “C” to prevent the cannula  10  from being withdrawn through the tissue “T.” The retention anchor  20 , is disposed on the elongated body  12  of the cannula  10  in the first configuration ( FIG.  3   ) and is slid distally along the elongated shaft  12  of the cannula  10  until the retention anchor  20  abuts or presses on the tissue “T.” 
     The retention anchor  20  is then transitioned to the second configuration ( FIG.  4   ) by pressing the washer  34  down into the annular recess  25  of the annular body  22  of the retention anchor  20 , in the direction of arrow “A,” to lock the retention anchor  20  onto the elongated shaft  12  of the cannula  10  by friction fit between the washer  34  and the elongated shaft  12 . The tissue “T” is thus sandwiched between the expandable anchor  16  and the retention anchor  20  to prevent the cannula  10  from being withdrawn from or over-inserted into the tissue “T.” In this manner, the surgical access assembly  1  is secured to the tissue “T” and longitudinal movement of the cannula  10  relative to the tissue “T” is prevented or minimized throughout insertion, withdrawal, and/or manipulation of a surgical instrument “S” through the cannula  10 . 
     Following the surgical procedure, the expandable anchor  16  is deflated to permit the withdrawal of the cannula  10  from the tissue “T.” The retention anchor  20  may remain secured to and disposed about the elongated shaft  12  of the cannula  10  in the second configuration during withdrawal of the cannula  10 , or may be moved to the first configuration prior to removal of the cannula  10  from the tissue “T” (e.g., by applying a force against the second surface  26  of the annular body  22  towards the first surface  24  to pop the washer  34  back into the first configuration). 
     While 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. It is to be understood, therefore, that the disclosure is not limited to the precise aspects described, and that various other changes and modifications may be effected by one skilled in the art without departing from the scope or spirit of the disclosure. Therefore, the above description should not be construed as limiting, but merely as exemplifications of aspects of the disclosure. Thus, the scope of the disclosure should be determined by the appended claims and their legal equivalents, rather than by the examples given.