Patent Publication Number: US-2010113866-A1

Title: Atraumatic medical device anchoring and delivery system

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is related and claims priority to U.S. application Ser. No. 12/430,824, filed Apr. 27, 2009, and entitled “Systems and Methods for Treating Stress Urinary Incontinence,” which is related and claims priority to U.S. Provisional Application No. 61/095,231, filed Nov. 3, 2008, and entitled “Systems and Methods for Treating Stress Urinary Incontinence,” each of which are hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to systems and methods for providing medical treatment and, more particularly, to systems and methods for providing medical treatment including means for attaching a structure to a patient and removing the structure without damage, either to the structure or the patient. 
     2. Description of the Related Art 
     Urinary incontinence (UI) is any involuntary leakage of urine. It is a common and distressing problem that may have a profound impact on quality of life. UI often results from an underlying treatable medical condition. 
     Continence and urination involve a balance between urethral closure and detrusor muscle activity. Urethral pressure normally exceeds bladder pressure, resulting in urine remaining in the bladder. The proximal urethra and the bladder are both within the pelvis. Intra-abdominal pressure increases, e.g., from coughing and sneezing, are typically transmitted to both the urethra and the bladder equally, leaving the pressure differential unchanged, resulting in continence. Normal urination is the result of changes in both of these pressure factors, i.e., urethral pressure decreasing and bladder pressure increasing. 
     UI affects women of all ages, however, UI is highly prevalent in women across their adult life span and its severity increases linearly with age. Up to 35% of the total population over the age of 60 years is estimated to have UI, with women twice as likely as men to experience UI. One in three women over the age of 60 years are estimated to have UI. 
     A leading form of UI is known as stress urinary incontinence (SUI). SUI is essentially due to pelvic floor muscle weakness. It results in a loss of small amounts of urine with coughing, laughing, sneezing, exercising or other movements that increase intra-abdominal pressure and thus increase pressure on the bladder. Physical changes resulting from pregnancy, childbirth and menopause often cause SUI. 
     The urethra is supported by fascia of the pelvic floor. If the fascial support is weakened, as it can be from pregnancy, childbirth or normal physiological changes in the body over the course life, the urethra can move downward at times of increased abdominal pressure, resulting in SUI. 
     A surgical procedure for treating SUI employs what is commonly referred to as a sling. A sling may consist of any desired material in any desired shape but often consists of a synthetic mesh material or a mesh of biomaterial, e.g., bovine, porcine or the patients&#39; own tissue, in the shape of a ribbon that is placed under the urethra. In practice, a sling surgically implanted beneath a patient&#39;s urethra replaces the deficient pelvic floor muscles and provides structural support under the urethra that is sufficient to limit or eliminate SUI. 
     A common surgical procedure for implanting a sling is referred to as the transobturator procedure. With this procedure, a pair of incisions are made near the groin at the level of the obturator fossa of the pelvic bone and one in the vagina. Sling carriers are passed through from the groin incisions to the vaginal incision. Extension arms connected to the sling are fixedly attached to the sling carriers and the sling carriers are moved to withdraw the extension arms from the pair of incisions made near the groin and to position the sling under the urethra. Thereafter, the extension arms are cut to free the sling carriers, sling tension is adjusted and the incision is closed. 
     The transobturator procedure involves passing the sling carriers from the two incisions made near the groin at the obturator of the pelvic bone to the vaginal incision. By necessity then, the sling carriers pass through the patient, increasing patient trauma that may include nerve damage. To limit such patient trauma, a less invasive surgical procedure has emerged in which a sling is implanted but only a single vaginal incision is required. However, existing slings, whether implanted using only a vaginal incision or the multiple-incision transobturator procedure, have further limitations, including the inability to reposition the sling. 
     For example, some current slings include an anchoring mechanism, such as a barbed fastener located at each end of the sling for implanting into the patient&#39;s tissue. The anchoring mechanism provides holding strength for the sling until post-surgical tissue growth enables the patient&#39;s tissue to provide supplemental long-term holding strength for the sling. It is not uncommon for a surgeon to improperly implant the sling, i.e., when device placement is not optimum for treatment of SUI. At such times, the surgeon must completely remove the sling from the patient and attempt to properly implant the removed sling. 
     To remove an improperly placed sling, a surgeon typically uses his or her hand, a surgical tool, e.g. a hemostat, or some combination thereof to grasp a portion of the sling and remove it from the patient. The process for removing the sling, once implanted in the patient, is difficult because it is not easy for the surgeon to see and grasp the implanted sling. Moreover, assuming the surgeon can even see or locate an improperly implanted sling, the surgeon must grasp whatever portion of the sling that he or she can to remove the device. Typically, the surgeon grasps an improperly implanted sling at a single position somewhere on the sling and employs considerable force to remove the device. The process of removing an improperly implanted sling using such considerable retraction force applied to a single position on the sling often damages the device. Specifically, the sling is often stretched or torn such that it cannot be reused. In such instances, the surgeon must use another sling to complete the procedure, resulting in increased cost for the procedure. 
     Even for slings that do not include an anchoring mechanism, such as a barbed fastener located at each end of the sling, device removal is an issue for an improperly implanted sling. In such instances, following device implantation with the transobturator procedure, the sling carriers which are fixed to the sling extension arms cannot be backed out to remove the sling from beneath the urethra. Accordingly, it is not possible to remove the sling for repositioning, if desired. 
     Existing slings also have limited holding strength. As noted above, post-surgical tissue growth enables the patient&#39;s tissue to provide supplemental long-term holding strength for the sling. However, until such time that post-surgical tissue growth enables the patient&#39;s tissue to provide supplemental long-term holding strength for the sling, means for providing preliminary holding strength are employed. Such preliminary holding strength systems include those which employ an anchoring mechanism, such as a barbed fastener located at each end of the sling, for implanting into the patient&#39;s tissue. Other slings do not employ an anchoring mechanism and simply rely on a friction fit between the sling and the patient&#39;s tissue to hold the sling in place. Regardless of the type of preliminary holding strength system that is employed, current slings continue to move following surgery, and therefore, would benefit from improved holding strength. 
     A need exists for systems and methods for treatment of SUI, which overcome these and other problems associated with the prior art. And more generally, a need exists for systems and methods for providing medical treatment including means for attaching a structure to a patient and removing the structure without damage, either to the structure or the patient. 
     SUMMARY OF THE INVENTION 
     In accordance with an embodiment of the present invention, a system for providing medical treatment is disclosed, the system comprising a structure for attachment to a patient, the structure having a first end and a second end; a first fastener including at least one retractable barb, said first fastener coupled to the first end of the structure for attachment; and a second fastener including at least one retractable barb, said second fastener coupled to the second end of the structure for attachment. 
     In accordance with another embodiment of the present invention, a method is disclosed for providing medical treatment, the method comprising providing a structure for attachment to a patient, the structure including a first end; a second end; a first fastener including at least one retractable barb, said first fastener coupled to the first end of the structure for attachment; and a second fastener including at least one retractable barb, said second fastener coupled to the second end of the structure for attachment. 
     In accordance with another embodiment of the present invention, a system is disclosed for providing medical treatment, the system comprising a structure for attachment to a patient, the structure having a first end and a second end; and a fastener including at least one retractable barb, said fastener coupled to the first end of the structure for attachment. 
     In accordance with another embodiment of the present invention, a system is disclosed for providing medical treatment, the system comprising a structure for attachment to a patient, the structure having a first end and a second end; and a fastener coupled to the first end of the structure and having a first configuration that provides a first level of holding force while in the patient and a second configuration that provides a second level of holding force while in the patient, the second level of holding force being higher than the first level of holding force, and the fastener being capable of being selectively transferred between the first configuration and the second configuration while in the patient. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed. 
     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a plan view of an embodiment of a medical device for use in treatment of urinary incontinence (UI), in accordance with systems and methods consistent with the present invention. 
         FIG. 1B  is a plan view of the embodiment of the medical device shown in  FIG. 1A , in accordance with systems and methods consistent with the present invention.  FIGS. 1A and 1B  together show part of a sequence for assembly of the medical device. 
         FIG. 1C  is a side elevation view of the embodiment of the medical device shown in  FIG. 1B , in accordance with systems and methods consistent with the present invention. 
         FIGS. 1D and 1E  are partial cross-sectional views taken along line D-D of  FIG. 1F , in accordance with systems and methods consistent with the present invention.  FIGS. 1D and 1E  together show part of a sequence for assembly of the medical device. 
         FIG. 1F  is a partial plan view of the embodiment of the medical device shown in  FIG. 1B , in accordance with systems and methods consistent with the present invention. 
         FIG. 2A  is a plan view of another embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 2B  is a plan view of another embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 3A  is a plan view of another embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 3B  is a plan view of another embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 4A  is a partial perspective view of an embodiment of a fastener for use with any embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 4B  is a partial perspective view of another embodiment of a fastener for use with any embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIG. 4C  is a partial perspective view of another embodiment of a fastener for use with any embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention. 
         FIGS. 4D and 4E  are cross sectional views taken along the line  4 D- 4 D in  FIG. 4C , showing an operational sequence for an embodiment of a retractable fastener, in accordance with systems and methods consistent with the present invention. 
         FIGS. 4F-4H  are partial elevation views of embodiments of fasteners for use with any embodiment of a medical device for use in treatment of UI, in accordance with systems and methods consistent with the present invention.  FIGS. 4F-4H  show exemplary tools for inserting and/or extracting a fastener. 
         FIG. 5A  is a block diagram of an embodiment of a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIG. 5B  is a side elevation view of an embodiment of a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIG. 5C  is a side elevation view of another embodiment of a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIG. 5D  is a plan view of another embodiment of a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIG. 5E  is a plan view of another embodiment of a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIG. 6A  is a side elevation view of an embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 6B-6D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 6A . Each side elevation view includes a cross-section to show interior portions as retractable barbs transition from a stowed state in  FIG. 6B  to a deployed state in  FIG. 6D . 
         FIG. 6E  is a side elevation view of the embodiment of a fastener from  FIG. 6A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 6F and 6G  are cross-sectional views taken respectively along lines  6 F- 6 F and  6 G- 6 G. 
         FIG. 7A  is a side elevation view of another embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 7B-7D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 7A . Each side elevation view includes a cross-section to show interior portions as retractable barbs transition from a stowed state in  FIG. 7B  to a deployed state in  FIG. 7D . 
         FIG. 7E  is a side elevation view of the embodiment of a fastener from  FIG. 7A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 7F and 7G  are cross-sectional views taken respectively along lines  7 F- 7 F and  7 G- 7 G. 
         FIG. 8A  is a side elevation view of another embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 8B-8D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 8A . Each side elevation view includes a cross-section to show interior portions as retractable barbs transition from a stowed state in  FIG. 8B  to a deployed state in  FIG. 8D . 
         FIG. 8E  is a side elevation view of the embodiment of a fastener from  FIG. 8A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 8F and 8G  are cross-sectional views taken respectively along lines  8 F- 8 F and  8 G- 8 G. 
         FIG. 9A  is a side elevation view of another embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 9B-9D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 9A . Each side elevation view includes a cross-section to show interior portions as a retractable barb transitions from an initial state in  FIG. 9B  to a deployed state in  FIG. 9D . 
         FIG. 9E  is a side elevation view of the embodiment of a fastener from  FIG. 9A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 9F and 9G  are cross-sectional views taken respectively along lines  9 F- 9 F and  9 G- 9 G. 
         FIG. 10A  is a side elevation view of another embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 10B-10D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 10A . Each side elevation view includes a cross-section to show interior portions as a retractable barb transitions from an initial state in  FIG. 10B  to a deployed state in  FIG. 10D . 
         FIG. 10E  is a side elevation view of the embodiment of a fastener from  FIG. 10A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 10F and 10G  are cross-sectional views taken respectively along lines  10 F- 10 F and  10 G- 10 G. 
         FIG. 11A  is a side elevation view of another embodiment of a fastener for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. 
         FIGS. 11B-11D  are a sequence of side elevation views of the embodiment of a fastener from  FIG. 11A . Each side elevation view includes a cross-section to show interior portions as a retractable barb transitions from an initial state in  FIG. 11B  to a deployed state in  FIG. 11D . 
         FIG. 11E  is a side elevation view of the embodiment of a fastener from  FIG. 11A , taken from the perspective of looking into the front tip of the fastener. 
         FIGS. 11F and 11G  are cross-sectional views taken respectively along lines  11 F- 11 F and  11 G- 11 G. 
         FIGS. 12A and 12B  are a sequence of side elevation views of an embodiment of a tool for inserting a fastener, in accordance with systems and methods consistent with the present invention. In this exemplary sequence, the fastener embodiment from  FIGS. 6A-6G  is first shown with the retractable barbs stowed in  FIG. 12A  and then deployed in  FIG. 12B . 
         FIG. 13  is a side elevation view of an embodiment of a tool for removing a fastener, in accordance with systems and methods consistent with the present invention. 
         FIG. 14  is a perspective view of an embodiment of a retractable barb member for use with the fastener embodiment depicted in  FIGS. 6A-6G . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the present exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. 
     Referring to  FIG. 1A , a plan view is shown of an embodiment of a medical device (or system)  10  for use in treatment of urinary incontinence (UI), in accordance with systems and methods consistent with the present invention. Medical device  10  comprises what those skilled in the art would refer to as an enhanced sling for treatment of UI. Those skilled in the art also recognize that a sling, such as medical device  10 , may be successful for treating stress urinary incontinence (SUI) and any other type of UI, now known or later discovered. 
     Moreover, those skilled in the art understand that a sling, such as medical device  10 , may be surgically implanted using a well known and minimally invasive procedure employing the insertion of a sling into a single vaginal incision. This procedure involves inserting a sling, such as medical device  10 , into the vaginal incision, positioning the sling under the patient&#39;s urethra and anchoring the ends of the sling into the patient&#39;s tissue to provide support to the urethra. When such urethral support is applied at the correct position, a sling, such as medical device  10 , can successfully ameliorate UI. As the details of this surgical procedure are well known, further details of the procedure are deemed unnecessary to understand the present invention and are therefore not set forth here. 
     Still with reference to  FIG. 1A , medical device  10  may include a strip  12 , one or more fasteners  14  (collectively, elements  14   a  and  14   b ), one or more apertures  16 , one or more aperture covers  20  and one or more cords  18 . 
     Strip  12  may comprise any material now known or later discovered for making slings that may be employed to treat UI. For example, strip  12  may comprise a synthetic mesh material, a mesh of biomaterial or a combination thereof. As is the case with current slings, regardless of the material employed to fabricate strip  12 , strip  12  requires some degree of flexibility. For example, strip  12  should have enough flexibility to permit the ends of strip  12  to be anchored above the center of strip  12 , essentially providing a curved, hammock-like structure to support a portion of the patient&#39;s urethra. At the same time, however, strip  12  should also provide rigidity suitable to support the patient&#39;s urethra. In general, strip  12  may have rigidity and flexibility consistent with now known or later discovered slings that may be employed to treat UI. 
     Strip  12  may have any desired shape and dimensions, however, in an exemplary embodiment, strip  12  may have a length in the range of 7 cm to 9 cm, a width in the range of 1 cm to 2 cm and a thickness in the range of 0.5 mm to 1 mm. Those skilled in the art understand that the aforementioned dimensions may extend outside the recited ranges for any reason, if so desired. For example, a larger patient may require a strip  12  of longer, wider and/or thicker dimensions. The ends of strip  12  may be tapered, as shown, tapered to a different degree or not tapered at all. 
     Strip  12  includes a primary axis, which is not labeled in  FIG. 1A  but extends lengthwise along the center of strip  12 . Strip  12  also includes a secondary axis, which is also not labeled but extends widthwise (or vertically in  FIG. 1A ) and crosses the center of strip  12 . Continuing with the hammock analogy set forth above, during surgical implantation, strip  12  is generally placed such that the patient&#39;s urethra rests orthogonally with respect to the primary axis. To be clear, this arrangement is not analogous to a person sleeping in a hammock in which case the person rests in alignment with the length of the hammock. The surface of strip  12  that is shown in  FIG. 1A  is not the urethra resting surface; the opposite side of strip  12 , as shown in  FIGS. 1C-1E , provides the urethra resting surface. 
     Still with reference to  FIG. 1A , medical device  10  may also include one or more fasteners  14 . As shown, medical device  10  may include a pair of fasteners  14 , one coupled to each end of strip  12 . Fasteners  14  may comprise any structure suitable for anchoring the ends of strip  12  into a patient&#39;s tissue, thereby providing support to the patient&#39;s urethra with strip  12 . Fasteners  14  may also be made from any material suitable for patient implantation and anchoring the ends of strip  12  into patient tissue, such as a plastic, a metal, a composite or any combination thereof suitable for patient implantation. 
     In an exemplary embodiment, fasteners  14  may include a shaft  14   b  coupled to an end of strip  12  and one or more barbs  14   a  coupled to shaft  14   b . As shown in  FIG. 1A , fasteners  14  include a plurality of barbs  14   a , however, a single barb  14   a  may be employed. Moreover, fasteners  14  are not limited to the structure, as shown in  FIG. 1A . Rather, fasteners  14  may employ any structure suitable for anchoring the ends of strip  12  into patient tissue. 
     Additionally, and as will be discussed in detail below, fasteners  14  may be retractable. More specifically, fasteners  14  may have selectable positions. For example, fasteners  14  may include a first position in which the barb  14   a  or barbs  14   a  are extended, as shown in  FIG. 1A , for anchoring into patient tissue, and a second position in which the barb  14   a  or barbs  14   a  are retracted to minimize tissue trauma when fastener  14  is removed from the patient&#39;s tissue. Moreover, it may be desirable to have the barb  14   a  or barbs  14   a  retracted during implanting of medical device  10 . While an exemplary embodiment for providing a retractable fastener  14  is set forth below in connection with the description of  FIGS. 4C-4E , those skilled in the art understand that fasteners  14  may be constructed in any one of a variety of different ways to provide a retractable fastener. 
     Again with reference to  FIG. 1A , medical device  10  may also include one or more apertures  16 , one or more aperture covers  20  and one or more cords  18 . 
     The one or more apertures  16  may take any shape or size and may be positioned anywhere along strip  12 . In an exemplary embodiment, however, strip  12  may include a pair of apertures  16 , each being located closer to a respective end of strip  12  than to the opposing end of strip  12 . For example, as shown in  FIG. 1A , apertures  16  are located in proximity to the two ends of strip  12 . As also shown in  FIG. 1A , apertures  16  may be circular in shape and include a diameter larger than the diameter of the smaller spaces between the mesh strands forming strip  12 . 
     As shown in  FIGS. 1D and 1E , strip  12  may provide an extension or support shelf  24  within each aperture  16  that provides a seating surface for a corresponding aperture cover  20 . Support shelves  24  may also provide locations where the ends of cords  18  may be fixedly attached. For each aperture  16  shown in  FIG. 1A , a cord  18  may extend through the apertures in aperture cover  20  and be fixedly attached at both ends to the respective support shelf  24 . Cords  18  may be made from any material suitable for patient implantation, such as a plastic, a metal, a composite or any combination thereof suitable for patient implantation. 
     The one or more apertures  16 , one or more aperture covers  20  and one or more cords  18  collectively provide two separate functions for medical device  10 . First, they enable the medical practitioner to remove an improperly placed strip  12 , without damaging strip  12 . For example, as noted for each aperture  16  shown in  FIG. 1A , a cord  18  may extend through the apertures in an aperture cover  20  and be fixedly attached at both ends to a respective support shelf  24 . Accordingly, if a medical practitioner is dissatisfied with the placement of strip  12 , once it is anchored to the patient with fasteners  14 , the practitioner may grasp aperture covers  20  (either by hand or with a suitable surgical instrument) and pull back on aperture covers  20  to remove fasteners  14  from patient tissue. Unlike prior art systems, this may be done without damaging strip  12 , thereby permitting reuse of the same strip  12 . Moreover, in embodiments of medical device  10  with 14 retractable fasteners  14 , the barb  14   a  or barbs  14  may be retracted  14  prior to removal of strip  12  to minimize patient trauma. 
     A second function of medical device  10  that is collectively provided by the one or more apertures  16 , one or more aperture covers  20  and one or more cords  18  is the ability to provide additional holding support for strip  12 . For example, assuming that the medical practitioner has anchored strip  12  to a desired position, the practitioner may cut each cord  18  (approximately at its midpoint), slide aperture covers  20  along their respective cords  18  and tie cords  18  snugly against their respective aperture covers  20  such that aperture covers  20  press firmly against respective support shelves  24 , creating a force applied against the patient&#39;s tissue to help hold medical device  10  in place (hereinafter the “seating force”). Aperture covers  20  may be made from any desired material that is suitable for patient implantation and more rigid than strip  12 , such as a plastic, a metal, a composite or any desired combination thereof. This rigidity differential between aperture cover  20  and strip  12  improves the effectiveness of the seating force holding medical device  10  in place. 
     Additionally, as shown in  FIG. 1C , an array of protrusions  22  may extend from strip  12  in proximity to apertures  16 . As such, the seating force will be applied near the array of protrusions  22 , which should further enhance the effectiveness of the seating force holding medical device  10  in place. The array of protrusions  22  may take any form or shape. As shown in  FIGS. 1C-1E , the array of protrusions  22  is circular and arranged in proximity to the perimeter of apertures  16 , though the array of protrusions  22  may take any other desired shape and may or may not reside in proximity to the perimeter of apertures  16 . The protrusions forming array  22  are in a curved shape bending outwardly with respect to apertures  16 . Those skilled in the art understand, however, that any other shape or arrangement may be employed for the protrusions forming array  22 , such as inwardly bending protrusions. The protrusions comprising array  22  may comprise any material suitable for patient implantation and for supplementing the holding support for medical device  10  such as a plastic, a metal, a composite or any combination thereof. 
     In an exemplary embodiment of medical device  10 , medical device  10  comprises an integral device in that the strip  12 , the one or more fasteners  14 , the one or more apertures  16 , the one or more aperture covers  20  and the one or more cords  18  are all fabricated into a single device in which no additional parts are required (although there may be tools, which are not part of the medical device  10 , that may be employed to insert and/or remove medical device  10 ). In a variation of medical device  10 , medical device  10  may comprise an integral device except for the following distinction, namely, that the cords  18 , as shown in  FIG. 1A , would be precut, such that each cord  18  would have an end attached to a respective support shelf  24  and an opposite free end. In this instance, the aperture covers  20  would not be held by a closed loop of a cord  18 ; instead the medical practitioner would thread each cord  18  into the respective apertures in the aperture covers  20  when he was ready to synch down the aperture covers  20  and tie them in place with the cords  18 . Thus, in this variation, medical device  10  may be considered an integral device, except for the aperture covers  20 , which are separate and installed during the surgical procedure. 
     Referring to  FIG. 1B , a plan view is shown of the embodiment of medical device  10  shown in  FIG. 1A .  FIGS. 1A and 1B  together show part of a sequence for assembly of medical device  10 . In  FIG. 1B , we assume that fasteners  14  are anchored in patient tissue and the medical practitioner is satisfied with device placement. Accordingly, the practitioner has cut each cord  18  (assuming the integral embodiment of medical device  10 ) and slid aperture covers  20  along their respective cords  18  in preparation to tie cords  18  snugly against their respective aperture covers  20 , creating the seating force to help hold medical device  10  in place. We note for the sake of clarity, however, that no patient is shown and that the angular positioning of medical device  10  does not reflect what angular positioning would actually look like installed in a patient (e.g., fasteners  14  would be canted up, instead of lying flat, as shown). 
     Referring to  FIG. 1C , a side elevation view is shown of the embodiment of medical device  10  of  FIG. 1B . As in  FIG. 1B , we assume that fasteners  14  are anchored in patient tissue and the medical practitioner is satisfied with device placement. Accordingly, the practitioner has cut each cord  18  (assuming the integral embodiment of medical device  10 ) and slid aperture covers  20  along their respective cords  18  in preparation to tie cords  18  snugly against their respective aperture covers  20 , creating the seating force to help hold medical device  10  in place. Again, we note for the sake of clarity, however, that no patient is shown and that the angular positioning of medical device  10  does not reflect what angular positioning would actually look like installed in a patient (e.g., fasteners  14  would be canted up, instead of lying flat, as shown). 
     Referring to  FIGS. 1D and 1E , partial cross-sectional views are shown of the embodiment of medical device  10  in  FIG. 1B .  FIGS. 1D and 1E  together show the seating of aperture cover  20  against support shelf  24 . In  FIG. 1D , the ends of cord  18  are shown fixedly attached to support shelf  24 .  FIG. 1D  also shows that the attachment points for cord  18  are not aligned with the apertures in aperture cover  20 , though they could be, if desired, however, having a slight alignment offset improves the holding strength once cord  18  is severed and tied down against aperture cover  20 . It also bears mentioning that the space between the outer edge of aperture cover  20  and the wall forming aperture  16  may be exaggerated, i.e., there may be a snug mechanical fit between the outer edge of aperture cover  20  and the wall forming aperture  16 . 
     Alternatively, there may be a small space between the outer edge of aperture cover  20  and the wall forming aperture  16 . Additionally, whether there is a space or a snug mechanical fit between the outer edge of aperture cover  20  and the wall forming aperture  16 , various additional mechanical interfaces may be employed. For example, a ring or other protrusion (not shown) may extend slightly from the outer edge of aperture cover  20  and a corresponding notch (not shown) may be produced in the wall forming aperture  16 , such that the ring or other protrusion mates with the notch to provide a tactile sensation to the medical practitioner when aperture cover  20  is in place (prior to tying cords  18 ). Similarly, one or more posts or other protrusions (not shown) may extend slightly from the bottom surface of aperture cover  20  for mating with one or more corresponding apertures (not shown), which may be produced in support shelf  24 , such that the one or more posts or other protrusions provide a tactile sensation to the medical practitioner when aperture cover  20  is in place, as well as assisting in proper alignment of aperture cover  20 . 
     Referring to  FIG. 1F , a partial plan view is shown of the embodiment of medical device  10  shown in  FIG. 1B . In this view, the practitioner has cut cord  18  (assuming the integral embodiment of medical device  10 ) and slid aperture cover  20  along cord  18  in preparation to tie cords  18  snugly against aperture cover  20 , creating the seating force to help hold medical device  10  in place. In this view, it is clear that the diameter of aperture  16  exceeds the diameter of any aperture in the regular pattern of apertures formed by the mesh strands in strip  12 . 
     Referring to  FIG. 2A , a plan view is shown of another embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. The embodiment of medical device  10  shown in  FIG. 2A  differs from the embodiment shown in  FIGS. 1A-1F  by including more than one fastener  14  on each end of strip  12 . Moreover, in the embodiment of medical device  10  shown in  FIG. 2A , each fastener  14  has an independent shaft  14   b  connected to an end of strip  12 . The use of multiple fasteners  14  on one or more ends of strip  12  may be called for in certain circumstances. For example, a larger patient having a larger pelvis may require more support that may be provided through use of multiple fasteners  14  on one or more ends of strip  12 . 
     Referring to  FIG. 2B , a plan view is shown of another embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. The embodiment of medical device  10  shown in  FIG. 2B  differs from the embodiment shown in  FIGS. 1A-1F  by including more than one fastener  14  on each end of strip  12 . Moreover, in the embodiment of medical device  10  shown in  FIG. 2B  each fastener  14  has an independent shaft  14   b  connected to a common member that is connected to an end of strip  12 . Again, the use of multiple fasteners  14  on one or more ends of strip  12  may be called for in certain circumstances. 
     Referring to  FIG. 3A , a plan view is shown of another embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. The embodiment of medical device  10  shown in  FIG. 3A  differs from the embodiment shown in  FIGS. 1A-1F  by including more than one aperture  16 , more than one aperture cover  20  and more than one cord  18  in proximity to each end of strip  12 . The use of more than one aperture  16 , more than one aperture cover  20  and more than one cord  18  in proximity to each end of strip  12  may be called for in certain circumstances. 
     Referring to  FIG. 3B , a plan view is shown of another embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. The embodiment of medical device  10  shown in  FIG. 3B  differs from the embodiment shown in  FIGS. 1A-1F  by including an aperture  16  and aperture cover  20  that is a shape other than circular (in this case, elliptical, though one may employ any desired shape) and located in proximity to each end of strip  12 . The use of an elliptically-shaped aperture  16  and aperture cover  20  (or other shape) may improve holding strength, as compared to a circularly-shaped aperture  16  and aperture cover  20 . 
     Referring to  FIG. 4A , a partial perspective view is shown of an embodiment of a fastener  14  for use with any embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. Fastener  14 , as shown in  FIG. 4A , corresponds to fastener  14 , as shown in  FIGS. 1A-1C ,  FIGS. 2A-2B  and  FIGS. 3A-3B . Fastener  14  may include a shaft  14   b  coupled to an end of strip  12  (not shown) and one or more barbs  14   a  coupled to shaft  14   b . As shown in  FIG. 4A , fastener  14  includes a plurality of barbs  14   a , however, a single barb  14   a  may be employed. Additionally, the barbs  14   a  shown in  FIG. 4A  traverse the entire perimeter of shaft  14   b , however and more generally, fastener  14  and any other fastener that may be employed with medical device  10  may include one or more barbs that traverse only a portion of the perimeter of the respective shaft. Moreover, fastener  14  and any fastener that may be employed with medical device  10  are not limited to the exemplary structures shown in this or any other figure of the application. Simply put, fasteners used with medical device  10  may employ any structure suitable for anchoring the ends of strip  12  into patient tissue. 
     Referring to  FIG. 4B , a partial perspective view is shown of another embodiment of a fastener  30  for use with any embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. Fastener  30  may include a shaft  30   b  coupled to an end of strip  12  (not shown) and one or more barbs  30   a  coupled to shaft  30   b . As shown in  FIG. 4B , fastener  30  includes a plurality of barbs  30   a , however, a single barb  30   a  may be employed. Additionally, the barbs  30   a  shown in  FIG. 4B  traverse less than the entire perimeter of shaft  30   b , however and more generally, fastener  30  and any other fastener that may be employed with medical device  10  may include one or more barbs that traverse a smaller portion of the perimeter of the respective shaft. Moreover, fastener  30  and any fastener that may be employed with medical device  10  are not limited to the exemplary structures shown in this or any other figure of the application. Simply put, fasteners used with medical device  10  may employ any structure suitable for anchoring the ends of strip  12  into patient tissue. 
     Referring to  FIG. 4C , a partial perspective view is shown of another embodiment of a fastener  32  for use with any embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention. Fastener  32  may include a shaft  32   b  coupled to an end of strip  12  (not shown) and one or more barbs  32   a  coupled to shaft  32   b . As shown in  FIG. 4C , fastener  32  includes a plurality of barbs  32   a , however, a single barb  32   a  may be employed. Additionally, the barbs  32   a  shown in  FIG. 4C  traverse less than the entire perimeter of shaft  32   b , however and more generally, fastener  32  and any other fastener that may be employed with medical device  10  may include one or more barbs that traverse a smaller or greater portion of the perimeter of the respective shaft. Moreover, fastener  32  and any fastener that may be employed with medical device  10  are not limited to the exemplary structures shown in this or any other figure of the application. Simply put, fasteners used with medical device  10  may employ any structure suitable for anchoring the ends of strip  12  into patient tissue. Fastener  32  also represents an exemplary embodiment of a retractable fastener, as will be discussed below with reference to  FIGS. 4D and 4E . 
     Referring to  FIGS. 4D and 4E , cross sectional views are shown taken along the line  4 D- 4 D in  FIG. 4C , showing an operational sequence for an embodiment of a retractable barbed fastener  32 , in accordance with systems and methods consistent with the present invention. In this exemplary embodiment, a system resides within shaft  32   b  for deploying and retracting barbs  32   a . This system may include an operating mechanism  32   c , a drive shaft  32   h , barb actuators  32   i  and  32   j  and a biasing spring  32   g . As shown in  FIG. 4D , barbs  32   a  are deployed, in response to the default position of operating mechanism  32   c  and biasing spring  32   g , i.e., the normal position of fastener  32  is open with barbs  32   a  deployed. Those skilled in the art appreciate that any retractable fastener employed with medical device  10  may alternatively have a normally closed or retracted fastener. Operating mechanism  32   c  may include an operating post  32   d , a guide member  32   e  and a spring  32   f.    
     To retract barbs  32   a , a medical practitioner depresses operating post  32   d  such that it depresses spring  32   f  and moves operating post  32   d  below the interior wall of shaft  32   b . As such guide member  32   e , which does not move below the outer wall of shaft  32   b , may be moved (to the right in  FIG. 4D ) along the outer surface of shaft  32   b , while operating post  32   d  slides (to the right in  FIG. 4D ) within a slot cut into the interior wall of shaft  32   b . The medical practitioner may employ a general purpose surgical instrument or a specifically-designed tool to operate operating mechanism  32   c , as described, such a tool design being within the capability of those skilled in the art. As guide member  32   e  continues to move (to the right in  FIG. 4D ) along the outer surface of shaft  32   b , it moves drive shaft  32   h , which similarly moves barb actuators  32   i  and  32   j  (to the right in  FIG. 4D ) to compress spring  32   g  and retract barbs  32   a . At a predetermined position located at the end of the interior guide slot for operating post  32   d , operating post  32   d  reaches an aperture in shaft  32   b , which frees operating post  32   d  to pop up in response to an expansion of spring  32   f  and barbs  32   a  are retracted, as shown in  FIG. 4E . 
     Using  FIG. 4E  as a starting point to deploy or redeploy barbs  32   a , the medical practitioner depresses operating post  32   d  such that it depresses spring  32   f  and moves operating post  32   d  below the interior wall of shaft  32   b . The now-compressed biasing spring  32   g  expands, moving operating mechanism  32   c  (to the left in  FIG. 4E ) until reaching a predetermined position located at the opposing end of the interior guide slot for operating post  32   d . At this point, operating post  32   d  reaches an aperture in shaft  32   b , which frees operating post  32   d  to pop up in response to an expansion of spring  32   f , deploying barbs  32   a , as shown in  FIG. 4D . For the sake of clarity, the system set forth above for providing a retractable fastener  32  is merely exemplary. Moreover, it is well within the skills of persons in the art to create a wide variety of retractable fasteners, any of which may be employed with any embodiment of medical device  10 . 
     Referring to  FIGS. 4F-4H , partial elevation views are shown of embodiments of fasteners  14  for use with any embodiment of medical device  10  for use in treatment of UI, in accordance with systems and methods consistent with the present invention.  FIGS. 4F-4H  also show exemplary tools  34 - 38  for inserting and/or extracting a fastener  14 . In  FIG. 4F , tool  34  is inserted within shaft  14   b  to drive barbs  14   a  into patient tissue, thereby inserting fastener  14 . While not explicitly shown in  FIG. 4F , those skilled in the art appreciate that tool  34  may be employed to disengage Fastener  14 , as well, using any one of a variety of different designs within the level of experience of those skilled in the art. In  FIG. 4G , tool  36  engages a position along shaft  14   b  for extracting fastener  14  (whether barbs  14  are retractable or not). In  FIG. 4H , tool  38  engages a position along shaft  14   b  to drive barbs  14   a  into patient tissue, thereby inserting fastener  14 . For the sake of clarity, the tools  34 - 38  set forth above for inserting and/or extracting fastener  14  (or any other fastener) are exemplary. Moreover, it is well within the skill level of those persons skilled in the art to create a wide variety of tools for inserting and/or extracting fastener  14  (or any other fastener), any of which may be employed with any embodiment of medical device  10 . 
     Referring to  FIG. 5A , a block diagram is shown of an embodiment of a system  40  for providing medical treatment, in accordance with systems and methods consistent with the present invention. System  40  may include any structure  42  that may be used for any medical purpose, including diagnosis, therapy, surgery or any other medical purpose for a patient. In an exemplary embodiment, structure  42  may comprise a strip of mesh for attachment to a patient under treatment for UI. 
     Structure  42  may be attached to the patient using fasteners  44 , which are coupled to structure  42 . Each fastener  44  may include one or more retractable barbs for attachment to the patient. The barbs may be retracted during insertion of fasteners  44  into the patient and then deployed for attachment to the patient. Having the barbs retracted during insertion of fasteners  44  will minimize patient trauma. If placement of the system  40  is deemed incorrect or otherwise undesired, the practitioner may remove system  40 , without damage thereof, and then reattach system  40  to the patient. In this regard, the practitioner may remove system  40  either with the barbs deployed or retracted, however, retracting the barbs prior to removal will minimize patient trauma. 
     Referring to  FIG. 5B , a side elevation view is shown of another embodiment of a system  46  for providing medical treatment, in accordance with systems and methods consistent with the present invention. System  46  may include any structure that may be used for any medical purpose, including diagnosis, therapy, surgery or any other medical purpose for a patient. In an exemplary embodiment, system  46  includes a strip  48  of mesh for attachment to a patient under treatment for UI. Mesh strip  48  differs from the other strips previously disclosed herein. For example, mesh strip  48  may not include one or more aperture covers  20 , one or more cords  18  or one or more arrays of protrusions  22 , as shown in  FIGS. 1A-1C . If desired, however, mesh strip  48  could include any of these features or any others disclosed above. 
     Mesh strip  48  may be attached to a patient using fasteners  44 , which are coupled to mesh strip  48 . Each fastener  44  may include one or more retractable barbs for attachment to the patient. The barbs for system  46  may be employed, as described above with respect to system  40 . System  46  may also include a cord  50  that is operably coupled to both fasteners  44  such that a practitioner may pull on cord  50 , causing the barbs to retract and the fasteners  44  to be removed from a patient. A ring  52  may also be coupled to cord  50  for convenience when pulling on cord  50  to retract the barbs and remove fasteners  44 . 
     Referring to  FIG. 5C , a side elevation view is shown of another embodiment of a system  54  for providing medical treatment, in accordance with systems and methods consistent with the present invention. System  54  may include any structure that may be used for any medical purpose, including diagnosis, therapy, surgery or any other medical purpose for a patient. In an exemplary embodiment, system  54  includes a strip  48  of mesh for attachment to a patient under treatment for UI. As noted with respect to  FIG. 5B , mesh strip  48  differs from the other strips previously disclosed herein. For example, mesh strip  48  does not include one or more aperture covers  20 , one or more cords  18  or one or more arrays of protrusions  22 , as shown in  FIGS. 1A-1C . If desired, however, mesh strip  48  could include any of these features or any others disclosed above. 
     Mesh strip  48  may be attached to a patient using fasteners  44 , which are coupled to mesh strip  48 . Each fastener  44  may include one or more retractable barbs for attachment to the patient. The barbs for system  54  may be employed, as described above with respect to system  40 . System  54  may also include a cord  50  that is coupled to each fastener  44 , on a one-per-fastener basis, as shown. Each cord  50  may be operably coupled to a respective fastener  44  such that a practitioner may pull on cord  50 , causing the respective barbs to retract and the respective fastener  44  to be removed from a patient. A ring  52  may also be coupled to each cord  50  for convenience when pulling on a respective cord  50  to retract the associated barbs and remove the respective fastener  44 . 
     Referring to  FIGS. 5D and 5E , plan views are shown of other embodiments of systems  56  and  62 , respectively, for providing medical treatment, in accordance with systems and methods consistent with the present invention. Systems  56  and  62  are analogous to system  54 , as shown in  FIG. 5C , as each fastener  44  is coupled to a dedicated cord  50  and ring  52  for barb retraction and fastener removal. 
     The plan view of  FIG. 5D  shows that the mesh strip  58  includes a portion  60  of maximum width between the first end of the strip  58  and the second end of the strip  58 . Wider portion  60  has a length parallel to the primary axis of the strip  58  that constitutes less than half the distance between the first end of the strip  58  and the second end of the strip  58 . Wider portion  60  affords greater surface area contact and support of a patient&#39;s urethra, once the strip  58  is attached beneath the urethra for treatment of UI, as described herein. The greater surface area contact and support associated with strip  58  is apparent when comparing the planar view of the strip  58  against the planar view of existing mesh strips, which have a basic linear shape as depicted in  FIG. 1A  (although without the apertures  16 ). 
     As shown in  FIG. 5E , the strip  61  also includes a wider portion between the ends of the strip  61 , which in this case is simply the midpoint since the strip  61  has an elliptical shape. As such, the strip  61  similarly provides greater surface area contact and support of a patient&#39;s urethra, once the strip  61  is attached beneath the urethra. Other shapes and configurations of mesh strips may be employed, as long as a portion of maximum width is between the first end of the strip and the second end of the strip and this wider portion has a length parallel to the primary axis of the strip that constitutes less than half the distance between the first end of the strip and the second end of the strip. This manner of increasing surface area contact and support of a patient&#39;s urethra may be employed with any system or method set forth herein. 
     While an exemplary embodiment for providing a retractable fastener  14  or  44  was previously set forth above in connection with the description of  FIGS. 4C-4E , those skilled in the art understand that retractable fasteners  14  or  44  may be constructed in any one of a variety of different ways. Described below with respect to  FIGS. 6-11  are a series of additional exemplary embodiments for providing fasteners  14  or  44  that are retractable. The fasteners shown in  FIGS. 6-11  are identified using specific reference numbers  64 ,  94 ,  120 ,  152 ,  162  and  180  which differ from the general reference numbers used elsewhere herein to represent fasteners, i.e.,  14  or  44 . This numbering convention is intended to indicate that there are several different fastener embodiments and that any fastener embodiment may be utilized in any combination with any system described herein. 
     Regarding  FIG. 6A , a side elevation view is shown of an embodiment of a fastener  64  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  64  may include a shaft  66  including one or more apertures  68  for allowing passage of one or more retractable barbs  82  and  84 . Fastener  64  may include a conical front portion  70  and a tip  72  of a size and shape to minimize resistance from insertion of fastener  64  into a patient. A cord  50  and a ring  52  may be coupled to fastener  64  to facilitate removal of fastener  64 , if and when desired. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  for removal of fastener  64 , if desired. 
     While shaft  66  may have any desired shape, in an exemplary embodiment, shaft  66  may include a generally tubular base portion coupled to a conical front portion  70 , as shown. Additionally, shaft  66  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  66  (from the end of the base to the tip  72 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  66  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 6B-6D , may be sized to be generally proportional to the overall length and width of shaft  66 . Shaft  66  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. 
     Referring to  FIG. 6B , the remaining fastener components are shown. A retractable barb member  74  (or member  74 ) may comprise an integral structure having a shaft  76  coupled to a pair of arms  78  and  80  and retractable barbs  84  and  82 , respectively. Member  74  may be biased to push arms  78  and  80  away from each other. While member  74  may comprise an integral structure, those skilled in the art understand that member  74  may comprise multiple parts, e.g., a pair of separate arms coupled together at a common point, such as the apex, and having means for providing force to move the arms apart. An interior wall  90  includes an aperture  92 , as shown in  FIG. 6G  (this cross section view removes member  74  to show aperture  92 ), to properly align member  74  such that the retractable barbs  82  and  84  are aligned for selective passage through one or more apertures  68 . Arms  78  and  80  may also include support fins  86  and  88  for support against an interior surface of shaft  66  when the retractable barbs  82  and  84  are deployed, as shown in  FIG. 6D . 
     Referring to  FIGS. 6B-6D , a sequence of side elevation views demonstrate a manner of deploying the retractable barbs  82  and  84  of the embodiment of fastener  64 .  FIG. 6B  depicts the retractable barbs  82  and  84  in an initial retracted position. From this condition, a practitioner may insert a tool (not shown here, however, an exemplary tool  192  is shown in  FIGS. 12A and 12B  and described below) in through the opening in the base of shaft  66  to apply force against shaft  76  and move member  74  toward tip  72 , causing the retractable barbs  82  and  84  to move apart and pass through apertures  68  into a deployed position, as shown in  FIG. 6D . As is evident from  FIGS. 6B-6D , in order for the retractable barbs  82  and  84  to transition between the stowed and deployed positions and vice versa, arms  78  and  80 , which swing across each other as shown during the transition, may be offset from each other such that they are generally not coplanar. 
     This aspect of retractable member  74  is also shown in a further embodiment of a retractable barb member  300  (or member  300 ), as shown in  FIG. 14 . Member  300  is largely similar to member  74  and may be employed in a fastener embodiment similar to fastener  64 , as shown in  FIGS. 6A-6G . In particular, member  300  includes a shaft  301  coupled to arms  302  and  303  and retractable barbs  304  and  306 , respectively. Like member  74 , member  300  may be biased such that arms  302  and  303  may move apart from one another into a deployed state, as shown in  FIG. 14 . Saying that member  300  may be biased such that arms  302  and  303  may move apart from one another into a deployed state means that arms  302  and  303  may move apart from one another unless restricted from doing so, such as from having member  300  stowed in a fastener shaft, like that shown in  FIG. 6B . As is evident from  FIG. 14 , arms  302  and  303  are generally not coplanar, allowing them to swing across one another during barb deployment and stowage operations. In proximity to a point of intersection  307  between shaft  301  and arms  302  and  303  are regions  308  and  309  that may provide a cam action during barb stowage. While member  300  is largely similar to member  74 , member  300  does not include the support fins  86  and  88 , as shown in  FIGS. 6B-6D , however, outer surfaces of each arm  302  and  303  may provide this support function, resting in contact with an internal shaft surface once deployed. 
       FIGS. 12A and 12B  show a sequence of side elevation views of an embodiment of a tool  192  for inserting fastener  64 , in accordance with systems and methods consistent with the present invention. In this exemplary sequence, fastener  64  is first shown with the barbs  82  and  84  stowed in  FIG. 12A  and then deployed in  FIG. 12B . Tool  192  may include a handle  194 , an actuator  196  coupled to a shaft  198  for moving a driver  200  against shaft  76  of fastener  64 . 
     Typically, the practitioner will have inserted fastener  64  into the patient with a tool, such as tool  192 , that may be placed around the edge of the base of shaft  66  to apply force against the base edge (this prevents inadvertent barb deployment while inserting fastener  64  into patient). During the insertion of fastener  64  into the patient, the retractable barbs  82  and  84  are typically left in the retracted or stowed position, as shown in  FIG. 6B , to limit patient trauma during fastener insertion. Once inserted, the retractable barbs  82  and  84  may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  64  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may employ tool  202 , as shown in  FIG. 13 . Tool  202  is an exemplary embodiment of a removal tool and those skilled in the art understand the other tool designs will suffice. In operation, the practitioner may locate ring  52  for fastener  64  an pull it taught, taking care not to move fastener  64  while the retractable barbs  82  and  84  are deployed. Then, the practitioner may engage the cord  50  with the slot located in the tip of tool  202 , so that the practitioner may easily guide the tool tip up to the base of shaft  66 . In this position, the practitioner may apply a holding force against the base of shaft  66 , while the practitioner pulls back on ring  52 , thereby drawing member  74  back to the stowed position, as shown in  FIG. 6B . Once the retractable barbs  82  and  84  are stowed, the practitioner may remove tool  202  and pull on ring  52  to remove fastener  64 , while minimizing patient trauma with retracted barbs  82  and  84 . Assuming other fasteners  64  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Regarding  FIG. 7A , a side elevation view is shown of an embodiment of a fastener  94  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  94  may include a shaft  96  including one or more apertures  98  for allowing passage of one or more retractable barbs  110  and  112 . Fastener  94  may include a conical front portion  100  and a tip  102  of a size and shape to minimize resistance from insertion of fastener  94  into a patient. A cord  50  and a ring  52  may be coupled to fastener  94  to facilitate removal of fastener  94 , if and when desired. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  for removal of fastener  94 , if desired. 
     While shaft  96  may have any desired shape, in an exemplary embodiment, shaft  96  may include a generally tubular base portion coupled to a conical front portion  100 , as shown. Additionally, shaft  96  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  96  (from the end of the base to the tip  102 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  96  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 7B-7D , may be sized to be generally proportional to the overall length and width of shaft  96 . Shaft  96  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. 
     Referring to  FIG. 7B , the remaining fastener components are shown. A retractable barb member  104  (or member  104 ) may comprise an integral structure having a pair of arms  106  and  108  and retractable barbs  110  and  112 , respectively. Member  104  may comprise an integral piece of material, such as a plastic, formed into arms  106  and  108  and the respective retractable barbs  110  and  112 , the two arms being coupled at an apex and biased to pull arms  106  and  108  toward each other. Appropriate biasing may determine the initial condition (stowed) of the retractable barbs  110  and  112 , such that they remain stowed within shaft  96 . While member  104  may comprise an integral structure, those skilled in the art understand that member  104  may comprise multiple parts, e.g., a pair of separate arms coupled together at a common point, such as the apex, and having means for providing force to move the arms toward each other. As shown in  FIG. 7B , a first portion of member  104  contacts the interior of shaft  96  in proximity to tip  102 , while the opposing portion of member  104  comprising the retractable barbs  110  and  112  rests against an actuator  116 . Actuator  116  may be coupled to a rotatable shaft  114 , which may be supported by interior shaft wall  118  including a threaded aperture to accommodate rotatable shaft  114 . 
     Referring to  FIGS. 7B-7D , a sequence of side elevation views demonstrate a manner of deploying the retractable barbs  110  and  112  of the embodiment of fastener  94 .  FIG. 7B  depicts the retractable barbs  110  and  112  in an initial retracted position. From this condition, a practitioner would insert a tool (not shown) in through the opening in the base of shaft  96  to engage the head of rotatable shaft  114  and rotate it. Rotation of shaft  114  causes linear translation of actuator  116  toward the apex of member  104 , causing the retractable barbs  110  and  112  to move apart and pass through apertures  98  into a deployed position, as shown in  FIG. 7D . The practitioner may pull back on ring  52  to apply a counterforce during the deployment of the retractable barbs  110  and  112 , to maintain fastener position. Indeed, this technique may be employed with any embodiment disclosed herein. 
     Typically, the practitioner will have inserted fastener  94  into the patient with a tool (not shown) that may be applied around the edge of shaft  96 . During the insertion of fastener  94  into the patient, the retractable barbs  110  and  112  are typically left in the retracted or stowed position, as shown in  FIG. 7B , to limit patient trauma during fastener insertion. Once inserted, the retractable barbs  110  and  112  may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  94  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may employ tool  202 , as shown in  FIG. 13 . In operation, the practitioner may locate ring  52  for fastener  94  and pull it taught, taking care not to move fastener  94  while the retractable barbs  110  and  112  are deployed. Then, the practitioner may engage the cord  50  with the slot located in the tip of tool  202 , so that the practitioner may easily guide the tool tip up to the base of shaft  96 . In this position, the practitioner may apply a holding force against the base of shaft  96 , while a second tool is inserted into shaft  96 , as previously described, to engage shaft  114 . Shaft  114  may then be rotated to reverse translation of shaft  114 , thereby moving actuator  116  back to the stowed position, as shown in  FIG. 7B . As actuator  116  retracts, the retractable barbs  110  and  112  return to the retracted position, as shown in  FIG. 7B , due to the biasing of member  104  to pull arms  106  and  108  towards one another. Once the retractable barbs  110  and  112  are stowed, the practitioner may remove tool  202  and pull on ring  52  to remove fastener  94 , while minimizing patient trauma with retracted barbs  110  and  112 . Assuming other fasteners  94  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Regarding  FIG. 8A , a side elevation view is shown of an embodiment of a fastener  120  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  120  may include a shaft  122  including one or more apertures  124  for allowing passage of one or more retractable barbs  136  and  138 . Fastener  120  may include a conical front portion  126  and a tip  128  of a size and shape to minimize resistance from insertion of fastener  120  into a patient. A cord  50  and a ring  52  may be coupled to fastener  120  to facilitate removal of fastener  120 , if and when desired. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  for removal of fastener  120 , if desired. 
     While shaft  122  may have any desired shape, in an exemplary embodiment, shaft  122  may include a generally tubular base portion coupled to a conical front portion  126 , as shown. Additionally, shaft  122  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  122  (from the end of the base to the tip  128 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  122  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 8B-8D , may be sized to be generally proportional to the overall length and width of shaft  122 . Shaft  122  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. 
     Referring to  FIG. 8B , the remaining fastener components are shown. A retractable barb member  130  (or member  130 ) may comprise an integral structure having a pair of arms  132  and  134  and retractable barbs  136  and  138 , respectively. Member  130  may comprise an integral piece of material, such as a plastic, formed into arms  132  and  134  and the respective retractable barbs  136  and  138 , the two arms being coupled at an apex and biased to pull arms  132  and  134  toward each other. Appropriate biasing may determine the initial condition (stowed) of the retractable barbs  136  and  138 , such that they remain stowed within shaft  122 . While member  130  may comprise an integral structure, those skilled in the art understand that member  130  may comprise multiple parts, e.g., a pair of separate arms coupled together at a common point, such as the apex, and having means for providing force to move the arms toward each other. As shown in  FIG. 8B , a first portion of member  130  contacts the interior of shaft  122  in proximity to tip  128 , while the opposing portion of member  130  comprising the retractable barbs  136  and  138  rests against an actuator  150 . Actuator  150  may be coupled to a shaft  140 , which may be supported by interior shaft wall  142  including an aperture to accommodate shaft  140 . Shaft  140  may include a pair of detents  146  and  148  for holding shaft  140  in a retracted position (detent  148 ) or a deployed position (detent  146 ). 
     Referring to  FIGS. 8B-8D , a sequence of side elevation views demonstrate a manner of deploying the retractable barbs  136  and  138  of the embodiment of fastener  120 .  FIG. 8B  depicts the retractable barbs  136  and  138  in an initial retracted position. From this condition, a practitioner would insert a tool (not shown) in through the opening in the base of shaft  122  to engage and push against the end of shaft  140 . Pushing the tool against the end of shaft  140  with sufficient force will exceed the holding force associated with detent  148 , thereby allowing movement of actuator  150  toward the apex of member  130 , causing the retractable barbs  136  and  138  to move apart and pass through apertures  124  into a deployed position, as shown in  FIG. 8D . In the deployed position, detent  146  will have engaged interior shaft wall  142 , thereby holding retractable barbs  136  and  138  in a deployed position. An additional ring  52  and cord  50  may be coupled to shaft  122  so the practitioner may pull back on this ring  52  to apply a counterforce during the deployment of the retractable barbs  136  and  138  which maintains fastener position. 
     Typically, the practitioner will have inserted fastener  120  into the patient with a tool (not shown) that may be applied around the base edge (to prevent inadvertent barb deployment while inserting fastener  120  into patient). During the insertion of fastener  120  into the patient, the retractable barbs  136  and  138  are typically left in the retracted or stowed position, as shown in  FIG. 8B , to limit patient trauma during fastener insertion. Once inserted, the retractable barbs  136  and  138  may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  120  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may employ tool  202 , as shown in  FIG. 13 . In operation, the practitioner may locate ring  52  for fastener  120  an pull it taught, taking care not to move fastener  120  while the retractable barbs  136  and  138  are deployed. Then, the practitioner may engage the cord  50  with the slot located in the tip of tool  202 , so that the practitioner may easily guide the tool tip up to the base of shaft  122 . In this position, the practitioner may apply a holding force against the base of shaft  122 , while pulling on ring  52  to move actuator  150  back to the stowed position, as shown in  FIG. 8B . As actuator  150  retracts, the retractable barbs  136  and  138  return to the retracted position, as shown in  FIG. 8B , due to the biasing of member  130  to pull arms  132  and  134  towards one another. Once the retractable barbs  136  are stowed, the practitioner may remove tool  202  and pull on ring  52  to remove fastener  120 , while minimizing patient trauma with retracted barbs  136  and  138 . Assuming other fasteners  120  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Regarding  FIG. 9A , a side elevation view is shown of an embodiment of a fastener  152  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  152  may include a shaft  154  having one or more thinned portions  160  forming one or more living hinges that may be selectively employed to form a retractable barb on an end of shaft  154 . Fastener  152  may include a conical front portion  157  and a tip  158  of a size and shape to minimize resistance from insertion of fastener  152  into a patient. A cord  50  and a ring  52  may be coupled to fastener  152  to facilitate removal of fastener  152 , if and when desired. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  for removal of fastener  152 , if desired. 
     While shaft  154  may have any desired shape, in an exemplary embodiment, shaft  154  may include a generally tubular base portion coupled to a conical front portion  157 , as shown. Additionally, shaft  154  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  154  (from the end of the base to the tip  158 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  154  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 9B-9D , may be sized to be generally proportional to the overall length and width of shaft  154 . Shaft  154  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. 
     Referring to  FIG. 9B , the remaining fastener components are shown. A shaft  161  may be rotatably coupled at one end to a bearing located near the tip  158  and on the inside of shaft  154 . An interior wall  158  including a threaded aperture provides further support to shaft  161 . The opposite end of shaft  161  provides a position for a tool to engage and rotate shaft  161  to selectively deploy and retract the retractable barb formed by the leading end of shaft  154 . 
     Referring to  FIGS. 9B-9D , a sequence of side elevation views demonstrate a manner of deploying the retractable barb formed by the leading end of shaft  154 .  FIG. 9B  depicts the retractable barb in an initial retracted position. From this condition, a practitioner would insert a tool (not shown) in through the opening in the base of shaft  154  to engage the head of shaft  161  and rotate it. Rotation of shaft  161  causes a linear translation that pulls tip  158  toward the base of shaft  154 , causing the living hinges formed by thinned portions  160  to deform, as shown in  FIGS. 9C and 9D . Once the translation is complete, the retractable barb is formed (or deployed) by the end of shaft  154 , as shown in  FIG. 9D . The practitioner may pull back on ring  52  to apply a counterforce during the deployment of the retractable barb which maintains fastener position. 
     Typically, the practitioner will have inserted fastener  152  into the patient with a tool (not shown) that may be applied around the edge of the base. During the insertion of fastener  152  into the patient, the retractable barb is typically left in the retracted or stowed position, as shown in  FIG. 9B , to limit patient trauma during fastener insertion. Once inserted, the retractable barb may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  152  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may employ tool  202 , as shown in  FIG. 13 . In operation, the practitioner may locate ring  52  for fastener  152  an pull it taught, taking care not to move fastener  152  while the retractable barb is deployed. Then, the practitioner may engage the cord  50  with the slot located in the tip of tool  202 , so that the practitioner may easily guide the tool tip up to the base of shaft  154 . In this position, the practitioner may apply a holding force against the base of shaft  154 , while a second tool is inserted into shaft  154 , as previously described, to engage the head of shaft  161 . Shaft  161  may then be rotated to reverse translation of shaft  161 , pushing toward the tip  158  of shaft  154  and returning shaft  154  to its initial configuration, as shown in  FIG. 9B  in which the barb is retracted. Once the barb is retracted, the practitioner may remove tool  202  and pull on ring  52  to remove fastener  152 , while minimizing patient trauma with retracted barb. Assuming other fasteners  152  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Regarding  FIG. 10A , a side elevation view is shown of an embodiment of a fastener  162  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  162  may include a shaft  164  having one or more thinned portions  170  forming one or more living hinges that may be selectively employed to form a retractable barb on an end of shaft  164 . Fastener  162  may include a conical front portion  168  and a tip  166  of a size and shape to minimize resistance from insertion of fastener  162  into a patient. A cord  50  and a ring  52  may be coupled to fastener  162  to facilitate barb deployment. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  when desired. 
     While shaft  164  may have any desired shape, in an exemplary embodiment, shaft  164  may include a generally tubular base portion coupled to a conical front portion  168 , as shown. Additionally, shaft  164  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  164  (from the end of the base to the tip  166 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  164  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 10B-10D , may be sized to be generally proportional to the overall length and width of shaft  164 . Shaft  164  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. 
     Referring to  FIG. 10B , the remaining fastener components are shown. A shaft  174  may be coupled at one end to the interior and near the tip  166  of shaft  164 . An interior wall  172  including an aperture provides further support to shaft  174 . Shaft  174  may include a pair of detents  176  and  178  for holding shaft  174  in a retracted position (detent  176 ) or a deployed position (detent  178 ). 
     Referring to  FIGS. 10B-10D , a sequence of side elevation views demonstrate a manner of deploying the retractable barb formed by the leading end of shaft  164 .  FIG. 10B  depicts the retractable barb in an initial retracted position. From this condition, a practitioner would pull on ring  52  and cord  50  to pull shaft  174  in a direction away from tip  166 . Use of tool  202 , as previously discussed, may be useful to hold fastener  162  in place during the operation to deploy the retractable barb. Pulling shaft  174  in a direction away from tip  166  causes the living hinges formed by thinned portions  170  to deform, as shown in  FIGS. 10C and 10D . Once the translation is complete, the retractable barb is formed (or deployed) by the end of shaft  164 , as shown in  FIG. 10D . 
     Typically, the practitioner will have inserted fastener  162  into the patient with a tool (not shown) that may be applied around the edge of the base. During the insertion of fastener  162  into the patient, the retractable barb is typically left in the retracted or stowed position, as shown in  FIG. 10B , to limit patient trauma during fastener insertion. Once inserted, the retractable barb may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  162  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may employ a second cord  50  and ring  52 . The first cord  50  and ring  25  may be attached, as shown in  FIG. 10B , for deploying the retractable barb. The second cord  50  and ring  25  (not shown) may be attached to shaft  164  for holding fastener  162  in place during the stowing operation of the retractable barb, as hereafter described. The practitioner may locate the second ring  25 , as previously discussed, and use it to apply a counterforce to shaft  164 , holding it in place during the stowing operation of the retractable barb. A tool (not shown) may be inserted in through the opening in the base of shaft  164  to apply force against shaft  174 . This will move shaft  174  toward the tip  166  of shaft  164  and return shaft  164  to its initial configuration, as shown in  FIG. 10B , in which the barb is retracted. Once the barb is retracted, the practitioner may use the second ring  25  to withdraw the fastener  162 , while minimizing patient trauma with retracted barb. Assuming other fasteners  162  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Regarding  FIG. 11A , a side elevation view is shown of an embodiment of a fastener  180  for use in a system for providing medical treatment, in accordance with systems and methods consistent with the present invention. Fastener  180  may include a shaft  182  having a conical front portion  186  and a tip  184  of a size and shape to minimize resistance from insertion of fastener  180  into a patient. A cord  50  and a ring  52  may be coupled to fastener  180  to facilitate removal of fastener  180 , if and when desired. The three dots shown in-line with cord  50  indicate that cord  50  may have any desired length, however, cord  50  is generally long enough for a practitioner to easily find ring  52  for removal of fastener  180 , if desired. 
     While shaft  182  may have any desired shape, in an exemplary embodiment, shaft  182  may include a generally tubular base portion coupled to a conical front portion  186 , as shown. Additionally, shaft  182  may be manufactured to any desired size or dimension, however, in an exemplary embodiment, the length of shaft  182  (from the end of the base to the tip  184 ) may fall in the range of 0.25 of an inch to 1.5 inches and the outer diameter of shaft  182  may fall in the range of 0.005 to 0.350 of an inch. The remaining fastener components, as shown in  FIGS. 11B-11D , may be sized to be generally proportional to the overall length and width of shaft  182 . Shaft  182  may also comprise an integrally formed structure made of any material suitable for patient implantation, such as a plastic. The base of shaft  182  may be sealed, except for an aperture. 
     Referring to  FIG. 11B , the remaining fastener components are shown. A hollow shaft  188  passes through the aperture in the base of shaft  182 . The opposing end of hollow shaft  188  may pass through an aperture in the tip  184  of shaft  182 . An inflatable body  190  may extend around the opening in the leading end of shaft  188  and be sealed such that fluid flow from the opening in the leading end of shaft  188  inflates inflatable body  190 . The opening in the leading end of shaft  188  need not extend outside of shaft  182 , but may instead be coplanar with the aperture in the tip  184  of shaft  182  or reside beneath the aperture in the tip  184  of shaft  182 , as long as the inflatable body  190  may be inflated as desired. 
     Referring to  FIGS. 11B-11D , a sequence of side elevation views demonstrate a manner of deploying the retractable barb formed by the inflatable body  190 .  FIG. 11B  depicts the retractable barb in an initial retracted position. From this condition, a practitioner would place a tool (not shown) around the aperture in the hollow shaft  188  extending outside of the base of shaft  182 . This tool may selectively force fluid into inflatable body  190 , causing deployment of the retractable barb, as shown in  FIGS. 11C and 11D . Once inflation is complete, the retractable barb is formed (or deployed) by inflatable body  190 , as shown in  FIG. 11D . The ring  52  and cord  50  may be employed to counterbalance any force applied by the inflating tool, which may cause the fastener  182  to move in an undesired manner. Inflation fluids may comprise any desired gas or liquid. In an exemplary embodiment, the inflation fluid comprises a gas, such as compressed air. Once a desired placement of fastener  180  is reached, a permanent fluid may be utilized (following drainage of the initial inflation fluid), such as a curable polymer, e.g., a curable polymer liquid, gel, foam, epoxy or the like, or a two-part curable system, e.g., a polyurethane, a collagen, a polyethylene glycol or the like. 
     Typically, the practitioner will have inserted fastener  180  into the patient with a tool (not shown) that may make contact with the base of shaft  182 . During the insertion of fastener  180  into the patient, the retractable barb is typically left in the retracted or stowed position, as shown in  FIG. 11B , to limit patient trauma during fastener insertion. Once inserted, the retractable barb may be deployed, as described above. Assuming the practitioner is not satisfied with the placement of fastener  180  or its related medical structure (not shown, but analogous to any such structure shown in any system embodiment described herein), the practitioner may remove the system (i.e., the medical structure and its related barb or barbs) without damage thereto or to the patient and then reattach the system in the desired location. 
     To remove the system, the practitioner may use the inflation tool to deflate inflatable body  190  (or simply drain the inflation fluid without use of the inflation tool). Once the inflation fluid has been drained, the retractable barb is returned to its initial configuration, as shown in  FIG. 11B . Once the retractable barb is stowed, the practitioner may use ring  52  to withdraw the fastener  180 , while minimizing patient trauma with retracted barb. Assuming other fasteners  180  are included with the subject system, the practitioner may similarly remove them and the related medical structure, intact and undamaged, for reuse. 
     Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. 
     For example, embodiments of the present invention may include a structure for attachment to a patient, the structure being coupled to one or more fasteners, wherein each fastener includes a source for providing variable friction (or holding force). A retractable barb provides variable friction (or holding force), however, there may be other fasteners that provide such variable friction (or holding force). 
     For example, one could envision a fastener including an controllable inflation source having an expandable stent-like device around it. Once the fastener was inserted to a desired location in a patient, the practitioner may inflate the controllable inflation source, expanding the stent-like device and increasing local friction. Once the stent-like device was expanded, the practitioner may deflate the controllable inflation source and remove it, leaving an expanded stent-like device providing increased local friction (or holding force). This exemplary system is not reversible, i.e., once the stent-like device is expanded, it remains so, meaning device retraction may produce patient trauma. 
     Thus, more generally, embodiments of the present invention may include any structure for attachment to a patient, wherein the structure is coupled to one or more fasteners that include any source for providing variable friction (or holding force) once implanted in the patient, whether the source is reversible or not. 
     It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.