Abstract:
The present disclosure relates to a surgical apparatus for positioning within an incision in tissue. In one aspect of the present disclosure, the surgical access apparatus includes an elongated seal member configured to removably receive at least one surgical object, and a deployment member. In another of the present disclosure, the surgical access apparatus includes a housing configured to removably receive at least one surgical object, an elongated member, and at least one filament. A method of percutaneously accessing an underlying surgical work site using the surgical apparatus is also disclosed.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 12/467,451, filed May 18, 2009, now U.S. Pat. No. 8,795,161, which claims the benefit of U.S. Provisional Application No. 61/075,548, filed Jun. 25, 2008, and the disclosures of each of the above-identified applications are hereby incorporated by reference in their respective entireties. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a surgical access apparatus for positioning within an incision in tissue. More particularly, the present disclosure relates to a surgical access apparatus that is adapted to removably receive one or more surgical objects, and configured for insertion into, and anchoring within, the incision. 
     2. Background of the Related Art 
     Today, many surgical procedures are performed through small incisions in the skin, as compared to the larger incisions typically required in traditional procedures, in an effort to reduce both trauma to the patient and recovery time. Generally, such procedures are referred to as “endoscopic”, unless performed on the patient&#39;s abdomen, in which case the procedure is referred to as “laparoscopic”. Throughout the present disclosure, the term “minimally invasive” should be understood to encompass both endoscopic and laparoscopic procedures. 
     In general, during a minimally invasive procedure, a surgical access apparatus or portal member is used to facilitate access to the surgical site with surgical instrumentation, e.g., endoscopes, obturators, staplers, and the like. A typical surgical access apparatus defines a passageway or lumen through which the surgical instrumentation is inserted and the procedure is carried out. 
     While many varieties of surgical access apparatus are known in the art, a continuing need exists for a surgical access apparatus that may be releasably and reliably secured within the patient&#39;s tissue throughout the duration of the minimally invasive procedure. 
     SUMMARY 
     The present disclosure relates to a surgical apparatus for positioning within an incision in tissue. In one aspect of the present disclosure, the surgical access apparatus includes an elongated seal member defining a longitudinal axis and a deployment member. 
     The elongated seal member is adapted to transition between first and second conditions. In the first condition, the elongated seal member defines a first transverse dimension sufficient to facilitate securement of the elongated seal member within the incision and a tissue engaging portion configured to engage the tissue in substantially sealed relation. In the second condition, the elongated seal member defines a second transverse dimension, which is less than the first transverse dimension, to facilitate insertion of the elongated seal member within the incision. 
     The elongated seal member is at least partially composed of an at least semi-resilient material such that the elongated seal member is biased towards the first condition thereof. The elongated seal member includes a longitudinal passageway for the reception and passage of a surgical object in substantially sealed relation. 
     The elongated seal member includes a proximal end, which may include a stiffening member, and a distal end, which may include a lip. The stiffening member is adapted to facilitate anchoring of the elongated seal member within the incision, and in one embodiment thereof, may be generally annular in shape. The lip extends outwardly relative to the longitudinal axis, when the elongated seal member is in the first condition, and is dimensioned to engage the tissue to resist removal of the elongated seal member therefrom. 
     In one embodiment, the elongated seal member defines an internal cavity that is configured to retain a fluid therein, and in another embodiment, the elongated seal member defines a variable cross-sectional dimension along the longitudinal axis. 
     The deployment member of the surgical access apparatus is at least partially positionable within the longitudinal passageway of the elongated seal member. The deployment member is secured to the elongated seal member along an internal surface thereof such that distal longitudinal movement of the deployment member along the longitudinal axis causes the elongated seal member to transition from the first condition to the second condition. When subjected to a predetermined force, the deployment member may be detached from the elongated seal member to permit the deployment member to be removed from the longitudinal passageway with the elongated seal member in the first condition, thereby leaving the elongated seal member within the incision to receive the surgical object. The deployment member may be releasably secured to the elongated seal member with an adhesive. 
     In one embodiment, the deployment member includes a sleeve having an opening to receive at least one digit of a user to thereby facilitate grasping and removal of the deployment member from the elongated seal member. 
     In another aspect of the present disclosure, the surgical access apparatus includes a housing configured to removably receive at least one surgical object, an elongated member extending distally from the housing, and at least one filament secured to the elongated member and extending proximally relative thereto. 
     The housing includes locking structure configured to engage the at least one filament and thereby maintain the second condition of the elongated member. The locking structure includes at least one channel formed in the housing that is configured to at least partially receive the at least one filament. In one embodiment, the locking structure may include a locking member that is repositionable between unlocked and locked positions. In this embodiment, the locking member defines a channel therethrough that is configured to at least partially receive the at least one filament. In the unlocked position, the channel of the locking member and the channel formed in the housing are substantially aligned, and in the locked position, the channel of the locking member and the channel formed in the housing are substantially misaligned. The locking member may be biased towards the locked position by a biasing member. 
     The elongated member includes a tubular braid defining an axial lumen that is configured to allow the at least one surgical object to pass therethrough. The braid is formed of a mesh of fibers which may be either substantially elastic, or substantially inelastic. 
     The elongated member is adapted to transition from a first condition, in which the elongated member is configured for at least partial insertion within the incision, and a second condition, in which the elongated member defines a tissue engaging portion configured to facilitate anchoring of the elongated member within the patient&#39;s tissue. 
     The filament, or filaments, are dimensioned for grasping by a user such that drawing the at least one filament proximally transitions the elongated member from the first condition to the second condition. The filament, or filaments, may be disposed within the lumen of the elongated member, or externally thereof. The filament, or filaments, may alternatively be secured to an intermediate or distal portion of the elongated member. 
     In one embodiment, the surgical access apparatus further includes a membrane disposed about at least a proximal portion of the elongated member to facilitate anchoring of the elongated member within the tissue. The membrane may also facilitate passage of the at least one surgical object through the elongated member. 
     In another aspect of the present disclosure, a method of percutaneously accessing an underlying surgical work site is disclosed. The first step of the method includes providing a surgical access apparatus having an elongated seal member and a deployment member. 
     The elongated seal member defines a longitudinal axis, a proximal end, and a distal end. The elongated seal member has a longitudinal passageway for reception and passage of a surgical object and is adapted to transition between a first condition and a second condition. In the first condition, the elongated seal member defines a first transverse dimension, and in the second condition, the elongated seal member defines a second transverse dimension. The elongated seal member comprises an at least a semi-resilient material to be normally biased towards the first condition thereof. 
     The deployment member is at least partially positionable within the longitudinal passageway of the elongated seal member and is secured to the elongated seal member along an internal surface adjacent the distal end thereof. Upon distal longitudinal movement of the deployment member along the longitudinal axis, the elongated seal member is caused to transition from the first condition to the second condition. 
     The deployment member is advanced distally within the longitudinal passageway of the elongated seal member to thereby transition the elongated seal member into the second condition, and secure the elongated seal member within the incision. Subsequently, the surgical access apparatus is inserted into the incision, the deployment member is removed from the elongated seal member, and the surgical object is inserted into the longitudinal passageway and used to perform at least one surgical function. Thereafter, the surgical object is removed from the longitudinal passageway, the elongated seal member is removed from the incision, and the incision is closed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein: 
         FIG. 1  is a perspective view of a surgical access apparatus including a seal member and a sleeve member in accordance with one aspect of the present disclosure. 
         FIG. 2A  is a side cross-sectional view of the seal member of  FIG. 1  shown in a first condition with the sleeve member removed therefrom. 
         FIG. 2B  is a side cross-sectional view of the seal member of  FIG. 1  shown in a first condition with the sleeve member inserted therein and secured thereto. 
         FIG. 3  is a side cross-sectional view of the seal member of  FIG. 1  inserted into an incision in tissue and shown in a first condition with a surgical object extending therethrough. 
         FIG. 4  is a side cross-sectional view of the seal member of  FIG. 1  shown in a second condition with the sleeve member inserted therein and secured thereto. 
         FIG. 5  is a side cross-sectional view of one embodiment of the seal member of  FIG. 1  incorporating a fluid disposed within an internal cavity. 
         FIG. 6  is a side cross-sectional view of a surgical access apparatus including a housing, an elongate member, shown in a first condition, and filaments in accordance with another aspect of the present disclosure. 
         FIG. 7  is a side cross-sectional view of the surgical access apparatus of  FIG. 6  with the elongate member shown in a second condition and inserted into an incision in a patient&#39;s tissue. 
         FIG. 8  is a side cross-sectional view of one embodiment of the surgical access apparatus of  FIG. 6  with the filaments disposed externally of the elongate member. 
         FIG. 9A  is a side cross-sectional view of one embodiment of locking structure for use with the surgical access apparatus of  FIG. 6  shown in a locked condition. 
         FIG. 9B  is a side cross-sectional view of the locking structure of  FIG. 9A  shown in an open condition. 
         FIGS. 10A-10B  are side cross-sectional views of another embodiment of the surgical access apparatus of  FIG. 6  including a membrane disposed about the elongate member, the elongate member being respectively shown in its first and second conditions. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     In the drawings and in the description which follows, in which like references numerals identify similar or identical elements, the term “proximal” will refer to the end of the apparatus which is closest to the user during use, while the term “distal” will refer to the end which is furthest from the user. Additionally, the term “incision” should be understood as referring to any opening in a patient&#39;s tissue, whether formed by the user or pre-existing. 
     With reference to  FIGS. 1A-3 , a surgical access apparatus  10  is disclosed that is removably positionable within a percutaneous incision  12  formed in a patient&#39;s tissue “T” during the course of a surgical procedure, e.g., a minimally invasive procedure, to facilitate access to a patient&#39;s underlying cavities, tissues, organs, and the like with one or more surgical objects “I” ( FIG. 3 ). In one aspect of the present disclosure, surgical access apparatus  10  includes a deployment member  100  that is releasably secured to an elongated seal member  200 . 
     Deployment member  100  is secured to an internal surface  210  of elongated seal member  200  such that at least a portion of deployment member  100  extends proximally of elongated seal member  200 . Deployment member  100  may be secured to internal surface  210  through any means suitable for the intended purpose of allowing deployment member  100  to be detached from elongated seal member  200  at the election of the user, including but not being limited to the use of a biocompatible adhesive. In one embodiment, as seen in  FIGS. 1A-3 , deployment member  100  is configured as a sleeve defining an opening  102  that extends at least partially therethrough. Opening  102  is configured to facilitate grasping of deployment member  100  by a user, e.g., by placing one or more digits therein. 
     Elongated seal member  200  includes a proximal portion  202 , an intermediate portion  204 , a distal portion  206 , and a passageway  208  defined by internal surface  210  and extending longitudinally through elongated seal member  200  along a longitudinal axis “A”. 
     Proximal portion  202  includes a proximal surface  212  extending outwardly with respect to the longitudinal axis “A” along a transverse axis “B”, and defines a first dimension D 1 . In one embodiment, as seen in  FIGS. 1-3 , proximal surface  212  may include at least one stiffening member  214 . Stiffening member  214  may extend distally from proximal portion  202  and at least partially into intermediate portion  204 , as depicted. Alternatively, stiffening member  214  may be substantially annular in configuration and disposed solely within proximal portion  202 . Stiffening member  214  may be formed of any biocompatible material suitable for the intended purpose of rigidifying elongated seal member  200  to facilitate the anchoring thereof within tissue, as discussed below. 
     Intermediate portion  204  extends distally from proximal portion  202 . Intermediate portion  204  and defines a second dimension D 2  along transverse axis “B” and a length “L”. The second dimension D 2  of intermediate portion  204  may be either substantially constant along its length “L”, or variable. 
     Distal portion  206  includes a lip  216  extending in transverse relation to the longitudinal axis “A”, along axis “B”, and defines a third dimension D 3 . Lip  216  is configured to engage tissue “T” ( FIG. 3 ) when elongated seal member  200  is disposed within percutaneous incision  12 , and thereby resist the removal of elongated seal member  200 . 
     The respective first and third dimensions D 1 , D 3  of proximal and distal portions  202 ,  206  are each greater than the second dimension D 2  of intermediate portion  204  such that elongated seal member  200  defines an “hour-glass” shape or configuration to assist in anchoring elongated seal member  200  within tissue “T” ( FIG. 3 ). However, an embodiment in which the second dimension D 2  of intermediate portion  204  is substantially equivalent to the respective dimensions D 1 , D 3  of proximal and distal portions  202 ,  206  is also within the scope of the present disclosure. Additionally, the third dimension D 3  of distal portion  206  may be appreciably smaller than the first dimension D 1  of proximal portion  202 , as shown in  FIGS. 1-3 , or alternatively, the respective first and third dimensions D 1 , D 3  of proximal and distal portions  202 ,  206  may be substantially equal. 
     The outermost surfaces of proximal and distal portions  202 ,  206  are substantially planar in configuration. However, an embodiment is also contemplated herein in which either or both of proximal and distal surfaces  202 ,  206 , respectively, define surfaces that are substantially arcuate to facilitate the insertion of elongated seal member  200  within incision  12 . 
     Passageway  208  is configured to removably receive surgical object “I” ( FIG. 3 ), as discussed in further detail below. Passageway  208  defines an inner dimension “D P ” that is smaller than the outer dimension “D I ” of surgical object “I” such that the introduction of surgical object “I” to elongated seal member  200  causes passageway  208  to expand or enlarge outwardly with respect to the longitudinal axis “A” along transverse axis “B”. Although the outer dimension “D I ” of surgical object “I” will generally lay within the range of about 3 mm to about 15 mm, the employ of surgical objects have substantially larger or smaller outer dimensions is also within the scope of the present disclosure. 
     Referring now to  FIG. 4  as well, elongated seal member  200  is adapted to transition from a first (or normal) condition ( FIGS. 1-3 ) to a second (or extended) condition ( FIG. 4 ). In the first condition, seal member  200  defines an overall length “L 1 ”, and the dimension D 2  of intermediate portion  204  is greater than that of the incision  12  to thereby facilitate the anchoring of elongated seal member  200 , as discussed in further detail below. To further assist in the anchoring of elongated seal member  200 , intermediate portion  204  exhibits a substantially irregular profile in the first condition in which a plurality of tissue engaging surfaces  218  are defined. The contact between tissue engaging surfaces  218  and tissue “T” may also form a substantially fluid-tight seal therebetween. When in the first condition, lip  216  extends outwardly along transverse axis “B” to further facilitate the anchoring of elongated seal member  200  within tissue “T” and resist the removal of seal member  200  therefrom. In the second condition, elongated seal member  200  defines an overall length “L 2 ” that is greater than the length “L 1 ” of the elongated seal member  200  when in the first condition, and intermediate portion  204  exhibits a profile that is substantially more uniform, in that tissue engaging surfaces  218  are substantially less prominent. Additionally, when in the second condition, lip  216  extends generally in the distal direction so as not to inhibit the insertion of elongated seal member  200  within incision  12 . 
     To facilitate the transition of elongated seal member  200  from the first condition to the second condition, the user grasps deployment member  100  and applies a force “F” thereto that is directed distally, thereby advancing deployment member  100  in that direction. As deployment member  100  is advanced, the engagement between deployment member  100  and internal surface  210  causes intermediate portion  204  to elongate, and lip  216  to deflect, in the distal direction. It should be noted that the elongation of elongated seal member  200  during the transition thereof from the first condition to the second condition may cause portions of elongated seal member  200 , e.g., intermediate and distal portions  202 ,  206 , respectively, to deform inwardly along transverse axis “B”, thereby reducing the dimensions of elongated seal member  200 , e.g., the respective dimensions D 2 , D 3  of intermediate and distal portions  202 ,  206 , and further facilitating the insertion of elongated seal member  200  within incision  12 . 
     Elongated seal member  200  may be formed of any suitable biocompatible material that is at least semi-elastic and deformable in nature, e.g., silicon or memory foam. Forming elongated seal member  200  of an elastic material allows elongated seal member  200  to resiliently transition between the first and second conditions thereof, and acts to return elongated seal member  200  to its first condition upon the removal of force “F” from deployment member  100 . Forming elongated seal member  200  of a material that is also deformable in nature allows intermediate portion  204  to conform to both the smaller dimensions of incision  12  upon the insertion of elongated seal member  200  therein, and permits passageway  208  to accommodate the larger dimensions of surgical object “I”. 
     Referring to  FIG. 5 , in one embodiment, the resiliency and deformability of elongated seal member  200  is achieved through the incorporation of one or more fluids  220 . Fluid  220  is retained within an internally defined cavity  222 . In this embodiment, fluid  220  may be any suitable biocompatible fluid, including but not being limited to air, water, or saline. 
     With respect now to  FIGS. 1-4 , the use and function of elongated seal member  200  during the course of a typical minimally invasive procedure will be discussed. Initially, the peritoneal cavity (not shown) may be insufflated with a suitable biocompatible gas such as, e.g., CO 2  gas, such that the cavity wall is raised and lifted away from the internal organs and tissue housed therein, providing greater access thereto. The insufflation may be performed with an insufflation needle or similar device, as is conventional in the art. It should be noted that the present disclosure also contemplates the employ of surgical access apparatus  10  during the course of a procedure in which insufflation is not required or utilized. 
     Either prior or subsequent to insufflation, incision  12  is created in the patient&#39;s tissue “T”. The dimensions of incision  12  may be varied dependent upon the nature of the procedure. However, when surgical apparatus  10  is employed during the course of procedure performed in an insufflated workspace, for reasons explained just below, it is particularly desirable to incise the tissue “T” so as to create an incision  12  defining dimensions smaller than those defined by intermediate portion  204  when elongated seal member  200  is in its first condition. 
     Prior to its insertion, elongated seal member  200  is in its first condition. In the first condition, the dimensions of elongated seal member  200 , e.g., the respective dimensions D 2 , D 3  of the intermediate and distal portions  202 ,  206 , may prohibit the insertion of elongated seal member  200  into incision  12 . To allow for the insertion of elongated seal member  200 , the user applies a force “F” to deployment member  100 , advancing deployment member  100  distally and transitioning elongated seal member  200  into its second condition. In the second condition, elongated seal member  200  is subject to a proximally directed biasing force “F B ” that is created by virtue of the resilient nature of the material comprising elongated seal member  200 . Biasing force “F B ” resists the influence of force “F” and is exerted upon deployment member  100  through the association between deployment member  100  and elongated seal member  200 . Upon transitioning into the second condition, elongated seal member  200  is inserted into incision  12  and force “F” is removed from deployment member  100 . Upon the removal of force “F”, biasing force “F B ” returns elongated seal member  200  to its first condition, thereby urging deployment member  100  proximally. After being restored to its first condition, tissue engaging surfaces  218  engage tissue “T” to thereby assist in securing elongated seal member  200  within the patient&#39;s tissue “T”. The user may then disengage deployment member  100  from internal surface  210  of passageway  208  by applying a predetermined force thereto, e.g., by pulling or drawing deployment member  100  proximally. Subsequently, the user may introduce one or more surgical objects “I” into passageway  208  such that the minimally invasive procedure may be carried out through apparatus  10 . 
     As indicated above, the deformable nature of the material comprising elongated seal member  200  allows intermediate portion  204  to conform to the smaller dimensions of incision  12  in addition to allowing passageway  208  to expand and accommodate the larger dimensions of surgical object “I”. Accordingly, elongated seal member  200  may create substantially fluid-tight seals with both tissue “T” and surgical object “I”, thereby substantially preventing the escape of insufflation gas, if any, and facilitating the secure anchoring of elongated seal member  200  within tissue “T” throughout the course of the procedure. 
     After completing the procedure and withdrawing surgical object “I”, elongated seal member  200  may be removed from incision  12 . It should be noted that the material comprising elongated seal member  200  allows for the deformation thereof during its withdrawal from incision  12  to thereby avoid any unnecessary trauma to the patient&#39;s tissue “T”. Thereafter, incision  12  may be closed. 
     Referring now to  FIGS. 6-7 , in an alternate aspect of the present disclosure, surgical access apparatus  10  includes a housing  300 , an elongated member  400  extending distally from housing  300 , and one or more filaments  500  that are secured to the elongated member  400 . 
     Housing  300  defines a longitudinal axis “A” and may be fabricated from any suitable biocompatible material including moldable polymeric materials, stainless steel, titanium or the like. Housing  300  is configured for manual engagement by a user and includes an opening (not shown) extending therethrough that is configured for the reception and passage of a surgical object “I”. Housing  300  includes an outer wall  302  which defines a flange  304  having a distal surface  306  and may, optionally, include an internal seal or valve (not shown), such as a duck-bill or zero-closure valve, adapted to close in the absence of surgical object “I”. Examples of such an internal seal or valve may be seen in commonly assigned U.S. Pat. No. 5,820,600 to Carlson, et al. and U.S. Pat. No. 6,702,787 to Racenet et al., which issued Oct. 13, 1998 and Mar. 9, 2004, respectively, the entire contents of which are incorporated by reference herein. Housing  300  further includes locking structure  308 , which is discussed in further detail below. 
     Elongated member  400  defines an axial lumen  402  that extends therethrough, along longitudinal axis “A”. Lumen  402  is configured for the reception and passage of a surgical object “I”. Elongated member  400  is configured as a braid  404  formed of a mesh of biocompatible fibers  406 . In one embodiment of elongated member  400 , fibers  406  may be formed of a substantially elastic material such that elongated member  400  may expand along an axis “B” that is transverse, e.g., orthogonal, in relation to longitudinal axis “A”. However, in an alternate embodiment, fibers  406  may be formed of a substantially inelastic material, e.g., polyamide fiber, stainless steel, or the like, such that elongated member  400  experiences a measure of shortening along longitudinal axis “A” upon the introduction of surgical object “I”, further details of which may be obtained through reference to U.S. Pat. No. 5,431,676 to Dubrul et al., the entire contents of which are incorporated by reference herein. The braid  404  may be comprised of fibers  406  having any suitable configuration, including but not being limited to round, flat, ribbon-like, or square. 
     Filaments  500  have proximal ends  502  that extend proximally beyond housing  300  and distal ends  504  that are secured to elongated member  400  at attachment points  506 . Attachment points  506  may be located at any suitable position along elongated member  400  proximal of a distal-most end  408  thereof, e.g., at a proximal section  410 , an intermediate section  412 , or a distal section  414 . As seen in  FIGS. 6-7 , in one embodiment, filaments  500  are disposed within lumen  402  of elongated member  400 , whereas in an alternate embodiment, filaments  500  are disposed externally of elongated member  400 , as seen in  FIG. 8 . In yet another embodiment, filaments  500  may be interlaced within the mesh comprising the elongated member  400 . Filaments  500  may be secured to elongated member  400  at attachment points  506  through any suitable means, such as adhesives. Alternatively, filaments  500  may be integrally formed with elongated member  400  such that filaments  500  constitute proximal extensions of fibers  406 . Filaments  500  are used to facilitate the transition of elongated member  400  from a first (or initial) condition ( FIG. 6 ) to a second (or activated) condition ( FIG. 7 ). 
     In the first condition, elongated member  400  defines an initial length “L 1 ” and an initial outer dimension “D 1 ”. Length “L 1 ” may vary depending on the intended usage for apparatus  10 , but in general, “L 1 ” will lie substantially within the range of about 10 cm to about 25 cm, although elongate members  400  that are substantially longer or shorter are also contemplated herein. The initial outer dimension “D 1 ” of elongate member is smaller than the dimensions of incision  12  such that elongated member  400  may be inserted and advanced distally through incision  12  will little or no resistance. 
     Upon the application of a force “F” to filaments  500  in the direction of arrow “B”, e.g., by pulling or drawing filaments  500  proximally, elongated member  400  is shortened along the longitudinal axis “A”, thereby transitioning into the second condition. In the second condition, elongated member  400  defines a length “L 2 ” that is appreciably less than its initial length “L 1 ”. Additionally, in the second condition, elongated member  400  defines a tissue engaging portion  416  having an outer dimension “D 2 ” that is appreciably greater than the outer dimension “D 1 ” of the elongated member  400  in the first condition. Tissue engaging portion  416  contacts the patient&#39;s tissue “T” about incision  12  and, in conjunction with flange  304  of housing  300 , facilitates the anchoring of apparatus  10 . Additionally, tissue engaging portion  416  acts to at least partially form a seal with tissue “T”. 
     As previously indicated, housing  300  of apparatus  10  includes locking structure  308 . Locking structure  308  acts to maintain elongated member  400  in the second condition thereof. As seen in  FIGS. 5-6 , in one embodiment, locking structure  308  includes one or more channels  310  formed in housing  300  and one or more engagement members  312 . Channels  310  extend at least partially through housing  300  and have an egress  314  formed either in a proximal-most surface  316  or outer wall  302  of housing  300 . In this embodiment, filaments  500  extend through channels  310  such that the proximal ends  502  thereof may be grasped by the user to thereby transition elongated member  400  into the shortened condition thereof. To maintain elongated member  400  in the second condition, the proximal ends  502  of filaments  500  are secured about engagement members  312 , e.g., by tying. Engagement members  312  may be any structure suitable for the intended purpose of releasably receiving filaments  500 , such as a hook. 
     As seen in  FIGS. 9A-9B , in an alternate embodiment, locking structure  308  includes channels  310  and a locking mechanism  318 . Locking mechanism  318  includes a locking member  320  having an aperture  322  formed therein, a handle portion  324 , and a biasing member  326 . Aperture  322  is configured to receive filaments  500  and handle portion  324  is configured for manual engagement by the user to facilitate the transition of locking mechanism  318  between a locked condition ( FIG. 9A ) and an open condition ( FIG. 9B ). In the locked condition, aperture  322  is in misalignment with channel  310  such that a portion  508  of filament  500  is disposed between the housing  300  and the locking member  320 , effectively prohibiting any movement of filaments  500  and thereby maintaining the second condition of elongated member  400 . When locking mechanism  318  is in the open condition, however, at least a portion of aperture  322  is aligned with channel  310  such that filament  500  may freely extend therethrough. Biasing member  326  urges locking mechanism  318  towards the locked condition and may be comprised of any structure or mechanism suitable for this intended purpose, e.g., a spring. 
     In alternative embodiments, locking mechanism  318  may comprise a single locking member  320  and a single biasing member, or a plurality of locking members engagable with one or more biasing members  326 . 
     Referring again to  FIGS. 6-7 , the use and function of seal member apparatus  10  will be discussed during the course of a typical minimally invasive procedure subsequent to the formation of incision  12  in the patient&#39;s tissue “T”. 
     Prior to the insertion of apparatus  10 , elongated member  400  is in its first condition such that distal-most end  408  of elongated member  400  may be inserted into incision  12 . The user then advances apparatus  10  distally until flange  304  abuts tissue “T”. Thereafter, the user draws filaments  500  proximally, thereby transitioning elongated member  400  into its second condition and forming tissue engaging portion  416 . The user may then secure filaments  500  to locking structure  308  to thereby maintain the second condition of elongated member  400  and anchor apparatus  10  within incision  12 . Surgical object “I” may then be inserted into and advanced distally through lumen  402  of elongated member  400  to carry out the surgical procedure through apparatus  10 . It should be noted that the insertion of surgical object “I” may dilate elongated member  400  outwardly, thereby forcing tubular braid  404  outwardly along transverse axis “B” and into tighter engagement with tissue “T”, thereby further securing apparatus  10  and enhancing the quality of the seal formed by the engagement of tissue “T” with flange  304  and tissue engaging portion  416 . 
     After completing the procedure and withdrawing surgical object “I”, filaments  500  may be disengaged from locking structure  308 , e.g., untied, such that elongate member may return to its initial condition. Apparatus  10  may then be withdrawn from incision  12  and incision  12  may be closed. 
     Referring now to  FIGS. 10A-10B , in another embodiment, apparatus  10  further includes a membrane  510  that is disposed about elongated member  400 . Membrane  510  may be composed of any suitable biocompatible material that is at least semi-resilient in nature and substantially impervious to fluids, e.g., blood or insufflation gas. The incorporation of membrane  510  may facilitate the insertion and passage of one or more surgical objects “I” into and through lumen  402  of elongated member  400 , and may constitute the means by which filaments  500  are secured to elongated member  400 . Membrane  510  may be disposed about elongated member  400  along its entire length, or in the alternative, membrane  510  may be selectively disposed about individual sections of elongated member  400 , e.g. proximal section  410 , intermediate section  412 , and/or distal section  414 . 
     When disposed about proximal section  410  of elongated member  400 , membrane  510  engages the patient&#39;s tissue “T” upon the transition of elongated member  400  from the first condition ( FIG. 10A ) into the second condition ( FIG. 10B ) thereof. The engagement of membrane  510  with tissue “T”, in conjunction with flange  304  of housing  300 , creates a substantially fluid-tight seal about incision  12 , thereby substantially preventing the escape of any fluids, e.g. blood or insufflation gas, if any, about apparatus  10 . 
     As previously discussed with respect to the embodiment of  FIGS. 6-7 , the introduction of surgical object “I” to elongated member  400  forces tubular braid  404  outwardly along transverse axis “B”. In the embodiment of  FIGS. 10A-10B , membrane  510  would also be forced outwardly and into tighter engagement with tissue “T”. Accordingly, membrane  510  may act to further anchor apparatus  10  within tissue “T” and tighten the seal created therewith by tissue engaging portion  416  and flange  304 . 
     Although the illustrative embodiments of the present disclosure have been described herein with reference to the accompanying drawings, the above description, disclosure, and figures should not be construed as limiting, but merely as exemplifications of particular embodiments. It is to be understood, therefore, that the disclosure is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the disclosure.