Patent Publication Number: US-2009221867-A1

Title: Integral Sling Connection System and Method

Description:
RELATED APPLICATIONS 
     This application claims priority to PCT Application No. PCT/US2006/060225 filed Oct. 25, 2006, which claims the benefit of U.S. Provisional Application No. 60/735,364, filed Nov. 11, 2005; 60/795,348 filed Apr. 27, 2006; and 60/841,479 filed Aug. 31, 2006, all of which are incorporated herein in their entirety by reference. 
    
    
     FIELD 
     The present invention pertains generally to surgically implantable mesh slings adapted to support a patient&#39;s urethra to treat urinary incontinence, to sling fabrication methods, and to sling implantation tools. 
     BACKGROUND 
     Incontinence is a condition characterized by involuntary loss of urine or fecal matter beyond the individual&#39;s control, that results in the loss or diminution of the ability to maintain the urethral or fecal sphincter closed as the bladder or rectum fills with urine or fecal matter. Causes for this condition include damage and/or loss of support to the urethral sphincter, which can occur for a variety of reasons including pelvic accidents and aging related deterioration of muscle and connective tissue supporting the urethra. 
     One recognized method for treating incontinence is to implant a sling to support the urethra and then to secure respective sling ends in the retro pubic space surrounding the urethra. Elongated “self-fixating” or “tension-free” slings do not require physical attachment to tissue or bone, and instead rely on tissue ingrowth into sling pores to stabilize the sling. Such slings are reported for example, in commonly assigned U.S. Pat. Nos. 6,382,214, 6,641,524, 6,652,450, and 6,911,003 and publications and patents cited therein, each of which are hereby incorporated by reference in their entirety. 
     The implantation of tension-free urethral slings involve the use of implantation needles and other instruments that create transvaginal, transobturator, supra-pubic, or pre-pubic exposures or pathways adjacent the urethra. The needles further include a connection system for coupling the sling ends to the needle ends to draw sling end portions through the desired pathways. 
     As exemplified in  FIG. 1 , an implantable urethral sling  10  generally includes an elongate mesh  40  and detachable protective sheaths  26 ,  28  encasing the mesh at each end portion  22 ,  24  of the sling  10 . Pre-formed dilators  12 ,  14  are attached to respective ends of the sheath using an adhesive, or by threading the sheath ends through an aperture in the dilators  12 ,  14  and then heat sealing the sheath ends. 
     The sling  10  is implanted in a patient using a surgical instrument such as the instruments  50  shown in  FIGS. 2 and 3 , which include handles  52  and needles  54 . These needles  50  have opposing helical shapes that are designed to form right and left pathways through each obturator foramen between a lateral incision and an incision in a patient&#39;s vagina. Each instrument  50  is then associated with the dilators  12 ,  14 . The dilators  12 ,  14  provide a relatively permanent attachment to the ends  62  of the needles  50 . The end portions of the sling  10  are then drawn through the respective right and left obturator foramen (ROF/LOF) pathways of the pelvis (P) as shown in  FIGS. 5 and 6  and further described in U.S. applications 2005/0043580 and 2005/0065395 publications and U.S. Pat. No. 6,911,003. 
     Generally speaking, the needle ends  62  are inserted axially into the dilators  12 ,  14 , and the end portions  22 ,  24  of the urethral sling  10  are drawn through the pathways trailing the sling connectors  12 ,  14  and needles to draw a central support portion  30  against the urethra to treat urinary incontinence. The fixation of the needle ends  62  with the dilators  12 ,  14  is robust to inhibit inadvertent detachment as the connectors dilate the pathways and the end portions  22 ,  24  of the urethral sling  10  are drawn through the pathways. The connectors  12 ,  14  are drawn out through the skin incisions, and the urethral sling  10  and encasing sheaths  26 ,  28  are severed adjacent to the connectors  12 ,  14 . The sheath portions  26 ,  28  and connectors  12 ,  14  are withdrawn from the right and left pathways over the sling mesh end portions  42 ,  44  exposing the urethral sling mesh to body tissue. The sling mesh end portions  42 ,  44  may be optionally sutured to subcutaneous tissue layers. Tissue pressure acutely stabilizes the exposed mesh, and tissue in-growth into the mesh pores chronically stabilizes the mesh in the pathway. Similar procedures for installing an elongated urethral sling to support the male urethra to alleviate incontinence are described in the above-referenced &#39;450 patent, and the invention described herein is also suitable for treating male incontinence. 
     The needles disclosed in U.S. published application 2005/0043580 publication patent have a curvature in a single plane and correspond generally to the BioArc™ SP and SPARC™ single use sling needles sold by American Medical Systems, Inc. U.S. Pat. No. 6,911,003 describes needles having curvature in a three-dimensional space that may be used to advance and position a sling along transobturator pathways. These needles generally correspond to the Monarc™ needles sold by American Medical Systems. 
     Although the implantable slings and surgical needles described above function suitably, there is a need for slings having connections that easily attach to and detach from corresponding surgical needles. There is also a need for cost effective methods for manufacturing such slings. 
     SUMMARY 
     One exemplary embodiment of the present invention provides a process for forming an implantable sling, which includes an elongate mesh material, by reducing the width of the first and second ends of the mesh and then molding a connector over each mesh end. In one embodiment, the molding process is carried out by injection molding. In another embodiment, the mesh ends are enclosed by one or more sheaths, and the connectors are molded over the sheaths. 
     Another embodiment of the present invention provides a system for treating urinary or fecal incontinence. The system includes a sling adapted to be implanted in a tissue pathway to treat urinary or fecal incontinence. The sling includes first and second sling connectors including a base portion injection molded over the first and second ends of the sling, and a filament loop secured to and extending from each base portion. 
     The system further includes first and second surgical instruments for implanting the sling. The first and second surgical instruments have a handle and respective right and left helical needle portions. The helical needle portions include a proximal needle end extending from the handle portion and a distal needle end including structure configured to releasably engage the sling connectors during implantation of the sling in the tissue pathway. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a urethral sling which provides context for the incorporation of embodiments of the present invention. 
         FIG. 2  shows a surgical instrument for implanting a sling that includes a handle and a helical needle for insertion into a transobturator pathway of a patient. 
         FIG. 3  shows a surgical instrument for implanting a sling that includes a handle and a helical needle for insertion into a transobturator pathway of a patient. 
         FIG. 4  shows a connection system for associating a sling end with a surgical instrument. 
         FIG. 5  shows the surgical instrument of  FIG. 3  extending along the left transobturator pathway. 
         FIG. 6  shows the surgical instrument of  FIG. 2  extending along the right transobturator pathway. 
         FIG. 7  shows an implantable sling according to an embodiment of the present invention, which includes connectors having apertures for associating the sling with a surgical instrument. 
         FIG. 8  shows one end of the sling shown in  FIG. 7 , and the end of a surgical instrument having structure capable for associating the instrument with the sling. 
         FIG. 9  shows the sling end and needle end of  FIG. 7  releasably associated as would occur during the implantation of the sling. 
         FIG. 10  shows a sling end according to another embodiment of the present invention, which includes a connector having a loop. 
         FIG. 11  shows a sling end having a loop connector, and a needle end releasably associated with the sling end as would occur during the implantation of the sling. 
         FIG. 12  shows a sling end according to another embodiment of the present invention, which includes a connector having a loop. 
         FIG. 13  shows a sling end according to another embodiment of the present invention, which includes a connector having a loop. 
         FIG. 14  shows a sling end according to another embodiment of the present invention, which includes a connector having a loop. 
         FIG. 15  shows a sling end according to another embodiment of the present invention, which includes a connector having a loop. 
         FIG. 16  shows a needle end according to another embodiment of the present invention, which includes an aperture for receiving a loop or similar sling connector. 
         FIG. 17  shows a sling connection system according to another embodiment of the present invention, which includes a sling connector having a loop and a needle end having a slot and recess for receiving the loop. 
         FIG. 18  shows a sling connection system according to another embodiment of the present invention. 
         FIG. 19  shows a sling connection system according to another embodiment of the present invention, which includes a sling connector having a loop with a reinforced portion and a needle end having a slot for receiving the loop. 
         FIG. 20  shows a needle end having an aperture, slot and recess for releasable association with a sling connector such as a loop connector. 
         FIG. 21  shows a needle end having multiple slots for receiving a sling connector such as a loop connector. 
         FIG. 22  shows multiple needle ends having various slot configurations for releasable association with a sling end connector such as a loop connector. 
         FIG. 23  shows a sling connection system according to another embodiment of the present invention. 
         FIG. 24  shows a sling implantation system or kit according to an embodiment of the present invention. 
         FIG. 25  shows the sling connection system of the implantation system shown in  FIG. 24 . 
         FIG. 26  show an end view of the surgical needle of the implantation system shown in  FIG. 24 . 
         FIG. 27  shows a cross-sectional view of the needle end of the implantation system shown in  FIG. 24 . 
         FIG. 28  shows a close-up view of the needle end of the implantation system shown in  FIG. 24 . 
         FIG. 29  shows a sling connection system according to another embodiment of the present invention, which includes a sling having a connector with a ball and cable structure, and a slot for releasably receiving the ball and cable. 
         FIG. 30  shows an alternate embodiment of the connector shown in  FIG. 29 . 
         FIG. 31  shows a top view of an alternate embodiment of the needle end shown in  FIG. 29 . 
         FIG. 32  shows a bottom view of the embodiment shown in  FIG. 31 . 
         FIG. 33  is a block diagram depicting the steps of forming insert molded sling connectors. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description, references are made to illustrative embodiments of methods and apparatus for carrying out the invention. It is understood that other embodiments can be utilized without departing from the scope of the invention. Additionally, various aspects of the disclosed embodiments may be combined with aspects of other disclosed embodiments within the scope of the present invention. In particular, the connection systems described herein may be used with various slings, needles and implantation procedures in accordance with the present invention. 
       FIG. 7  illustrates an incontinence sling  110  for treating urinary or fecal incontinence according to one exemplary embodiment of the present invention. The sling  110  has sling connectors  112 ,  114  at respective end portions of the sling  110 . The sling connectors  112 ,  114  include integrally molded loop portions  146 ,  148 , which are readily attachable to and detachable from a surgical needle such as needle  150  illustrated in  FIGS. 8-9 . A sling body  120  further includes center portion  130  and end portions  132 ,  134  encased within sheaths  122 ,  124 . Each of the sling connectors  112 ,  114  is molded over mesh ends  142 ,  144  and/or respective sheath ends  126 ,  128  by an injection molding process described below with reference to  FIG. 33 . 
     The center portion  130  and end portions  132 ,  134  can be formed from a synthetic material such as a polypropylene mesh. Alternatively some or all of these sling portions can be formed from a biocompatible material such as mammal dermis. 
     As further shown in  FIGS. 8 and 9 , the needle  150  includes a distal end  160  with a hook-shaped needle end  162 . Suitable needle shapes  150  include the helical shapes shown in  FIGS. 1-6 , as well as other surgical needles suitable for implanting incontinence slings. The hook-shaped needle end  162  has a prong or hook  164  dimensioned to be received into the holes  146 ,  148  to draw the end portions  132 ,  134  (see  FIG. 7 ) of the sling  110  through the tissue pathways formed by the needle  150  (see  FIGS. 5 and 6 ). Additional suitable hook configurations described herein may also be used with the sling embodiments illustrated in  FIGS. 7-9 . 
       FIGS. 10-24  depict additional embodiments of the present invention, in which the sling connectors include a suture loop integrally formed with the sling sheath and/or mesh end. Suitable needles for use with this embodiment include the hook-shaped configuration described above and additional configurations described herein. It will be evident to persons of skill in the art that although only one sling end is shown and described, a second sling end having the same features is also present. 
       FIG. 10  illustrates a sling  110  end according to an embodiment of the present invention, which includes a sling connector  112  molded over the sling end  110 , and more particularly over a sheath end  126  and/or a mesh end  142 . The sling connector  112  includes a base portion  150  and a suture loop  154  secured to the base portion  150 . The base portion  150  for this and other embodiments may be formed by injection molding a polymer material such as polypropylene or polyethylene over the sling end  110  as described in greater detail below. Suitable suture loops  154  or other filaments possess sufficient integrity to withstand the implantation process, while still having a significant degree of flexibility. Polyester sutures are suitable for certain embodiments due to its higher melting point. Other embodiments of the present invention include various natural and synthetic fibers and/or filaments, coated sutures (including reinforcement coatings), braided sutures or other suitable filament materials. The length of the suture loop  154  can vary depending on the type of sling being implanted, the configuration of the corresponding needle connector and the preference of the clinician(s) performing the procedure. 
       FIG. 11  shows a suture loop  154  releasably attached to hook  164  of needle  150  according to an embodiment of the present invention. In this manner, the sling  110  may be pulled through surgical pathways as described with reference to  FIGS. 1-6  (or by other conventional implantation procedures), and the needle  150  can then be easily released or disengaged from the suture loop  154 . 
       FIGS. 12-16  show various approaches for securing the suture loops  154  to the base portion  150  of the connector  112 , to the sheath end  126  and/or to the mesh end  142 .  FIG. 12  shows a cross-sectional view of another embodiment of the present invention in which each end  160 ,  162  of a loop is inserted into a through-hole  164  in the base portion  150  and a knot  166  is then formed proximal to the base portion  150  to complete the suture loop  154  and to prevent the suture loop  154  from pulling through the base portion  150  during implantation. In this embodiment, the suture end  160  can be tied directly to the mesh end  142  or to the sheath end  126 . If two sutures are used, another knot can be formed at the distal end of the sutures to complete the suture loop. The embodiment shown in  FIG. 13  is similar to  FIG. 12  except that the suture ends  160 ,  162  are each inserted through separate through-holes  164 ,  165 . 
       FIGS. 14 and 15  illustrate embodiments in which the suture loop  154  is secured to the base portion  150  during a molding process such as the injection molding process described with reference to  FIG. 33 . In the embodiment shown in  FIG. 14 , the through-hole  164  extends transversely to the length of the base portions  150 . 
       FIGS. 16-23  show additional embodiments of the present invention that utilize slings having suture loops at each end and connectors that releasably attach to the suture loops.  FIG. 16  shows an embodiment in which a needle end  160  includes a through-hole  170 , and the suture loop  154  is releasably associated with the needle end  160  by threading the suture loop  154  through the through-hole  170  and then hooking the loop  154  around the needle end  160 . Alternatively, the needle end  160  could include both a through-hole  170  and a hook such that the suture loop  154  is first threaded through the through-hole  170 , and is then further retained by the hook. 
       FIG. 17  shows an embodiment in which the suture loop  154  has a narrowed portion  172  which fits into a corresponding slot  174  and recess  175  in the needle end  160  such that the loop  154  is retained in the recess  175  during implantation unless the narrowed portion  172  is aligned with the slot  174 . 
       FIG. 18  shows an embodiment in which the base portion  150  includes a tube  176  into which the needle end  160  can be inserted in order to align the base portion  150  with the needle end  160  during implantation.  FIG. 19  shows an embodiment in which a portion of the suture loop  154  includes a stiffener or bead  178 , which can be inserted and releasably retained in a corresponding slot arrangement  180  that includes an opening  182  for receiving the bead  178  and a narrow slot  184  that retains the bead  178 . 
       FIG. 20  shows a needle-hook embodiment having a slot  174 , a recess  186  and a through-hole  188 . In this embodiment, a suture loop can be threaded through the slot  174  and the through-hole  188  and is then looped back over the needle end  160  and into the slot  174  such that it is retained in the recess  186 . This arrangement may reduce the chance that the loop unintentionally detaches from the needle end  160 . 
       FIG. 21  shows an embodiment in which the needle end  160  includes multiple (2 or more) holes  188  and  190  through which a suture loop can be threaded prior to retaining the loop over the needle end  160 . The needle end  160  may optionally include a hook or similar retention structure as well.  FIG. 22  shows additional needle end  160  structure which include various slots  192  for retaining a suture loop. 
       FIG. 23  shows an embodiment in which the suture loop  154  is inserted through a through-hole  194  in the needle end  160 , and is then hooked onto the base portion  150  of the sling connector instead of the needle end  160  as shown in previous embodiments. The base portion  150  in the illustrated embodiment includes a tube portion  196  to assist with aligning the needle end  160 . The base portion  150  could also include a recess, slot, notch or other structure to further retain the loop during sling implantation. 
       FIG. 24  shows an sling implantation assembly  200  according to an embodiment of the present invention. The assembly  200  includes a container  205 , a sling  210 , and surgical needles  212 ,  214 . The sling  210  includes sling ends  216 ,  218  with connectors  220 ,  222 . The connectors  220 ,  222  include respective base portions  224 ,  226  and loops  228 ,  230 . The needles  212 ,  214  have opposing helixes  232 ,  234  for creating tissue pathways through the right obturator foramen and left obturator foramen of a patient, and needle ends  236 ,  238  for releasable association with the sling connectors  220 ,  222 . As further shown in  FIGS. 25-28 , the needle ends  236 ,  238  include slots  240 ,  242  for receiving loops  228 ,  230 , and recesses  244 ,  246  for releasably retaining the loops  228 ,  230  during implantation. From the perspective shown in  FIG. 27 , the slots  240 ,  242  and recesses  244 ,  246  form “H” shaped connectors. 
       FIG. 29  illustrates an additional embodiment of the present invention, in which each sling end includes a connector  112  having a base portion  250 , a cable  252  extending from base portion  250  and a ball portion  254  formed at a distal end of the cable  252 . A corresponding needle end  160  includes a slot  256  with an opening  258  at one end. In use, the ball portion  254  can be inserted into the opening  258  and the cable  252  can then be pulled through the slot  256  to provide releasable association. 
       FIG. 30  illustrates an embodiment in which the base portion  250  is formed from a separate material than the cable  252  and ball  254  portions. In these embodiments, the base portion  250  may be molded over the sling end  142 ,  126  and  144  and  128  and around the cable  252  and ball  254  portions as described with reference to  FIG. 33 . One end of the cable  252  may also include an anchor  260  to retain the cable in the base portions  250 . The cable  252  and ball  254  portions may be formed from the same type of material as the base portion  250 . Alternatively, the base portion  250  could be formed from a polymer, and the cable  252  and ball  254  portions could be formed from a metal or a different polymer. 
       FIGS. 31 and 32  show various views of a needle end  160  having a slot and opening arrangement according to another embodiment of the present invention. As illustrated, the needle end includes a through-hole  270 , a seat  272  located on one side of the needle, and a channel  274  extending therebetween. On the side of the needle end  160  opposite the seat  272 , the channel  274  extends to a distal tip  276  of the needle end  160 . In this embodiment, through-hole  270  is sized to receive the ball portion  254  of the sling connector (see  FIG. 29 ) and to allow the ball portion  254  to extend through both sides of the through-hole  270 . The channel  274  is configured to allow the cable portion  252  to pass through until the ball portion  254  is received by the recess  272 . The seat  272  is sized such that the ball portion  254  is retained in the seat  272 . Once the ball portion  254  is retained in the seat  272 , the cable  252  can be aligned in the channel  274  up to the distal tip  276 . The sling connector can be released from the needle end  160  by sliding the cable  252  in the opposite direction in the channel and then by extracting the ball portion  254  through the through-hole  270 . 
     The needle embodiments shown in  FIGS. 31 and 32  could be modified such that either side of the slot arrangement could retain the ball and cable by including a recess and groove on both sides of the needle. Additionally, although the foregoing embodiments illustrate a ball portion at the end of the cable, other shapes, including a half circle, cone cylinder, or disk could also be used. A slot portion could also be molded onto each sling end, and the ball and cable could be attached to the end of the needle in another embodiment. 
     The steps of forming and integrally attaching the sling connectors to the sheath and/or mesh ends for select embodiments is described in  FIG. 33 . In step S 100 , a suitable injection mold is provided that has a mold cavity shaped to receive an end portion of the sling body and to integrally form a base portion over each sling end. The sling is formed in step S 102  following any suitable fabrication process that forms an elongate mesh sling that is generally contained within a protective sheath. End segments of the resulting sling are trimmed, longitudinally folded or otherwise formed into a generally conical configuration in step S 104  to fit into a portion of the mold cavity. A molding compound including a polymer such as polypropylene or a derivative thereof is injected into the mold cavity and cured in step S 106 . The sling connector is removed from the mold and trimmed after curing in step S 108 . 
     In embodiments in which the base portion and other portions of the connector (e.g., suture loop) are formed from discrete components, the discrete connection components can be separately formed and then inserted into the mold cavity prior to molding the base portion over the sling ends. In this manner, the discrete connection component is integrally formed with the base portion. In other embodiments, the discrete connection components are attached to the base portion and/or sling ends after the base portion is molded over the sling ends via through-holes, interference fits and the like. 
     There are several potential benefits to securing the sling ends and connectors in this manner. For example, injection molding tends to be more efficient because a separate dilator need not be formed. Also, injection molding may be easier to automate on a commercial scale. Further, injection molding allows discrete connection components such as a suture loop to be secured to the sling end in a single step. 
     Various alternative embodiments are also contemplated as part of the present invention. For example, the mesh portions of the sling described herein could include a bioactive material at the central portion. Additionally, the central portion could be formed with an increased width compared to the sling ends to accommodate fecal incontinence treatment by implanting the sling via suprapubic, retropubic, transvaginal, transurethral, transobturator or near-obturator pathways. In further embodiments, the sling ends described herein could be replaced with tissue anchors that can be easily associated with surgical needle and fixed in hard or soft tissue via at least one vaginal or perineal incision. 
     Although embodiments of the present invention have been described with reference to the treatment of female urinary continence, it should be appreciated that many of these embodiments would also be suitable to implant and repair a variety of pelvic conditions in both males and females. For example, embodiments of the present invention would be suitable for a variety of pelvic floor repairs and/or treatments, including pelvic organ prolapse repair, levator hiatus repair, fecal incontinence treatment, male urinary incontinence treatment, perineal body support and hysterectomy support. 
     All patents, applications, and publications referenced herein are hereby incorporated by reference in their entireties.