Urinary incontinence affects a large number of women and, consequently, various approaches have been developed to treat female urinary incontinence. Those skilled in the art will be familiar with approaches ranging from pelvic floor exercises to surgical techniques such as Burch colposuspension and Stamey type endoscopic procedures in which the sutures are placed so as to elevate the bladder neck.
One known procedure positions a sling loosely under the urethra. It is generally understood that this treatment alleviates urinary incontinence by occluding the mid-urethra (for example at a time of raised abdominal pressure by coughing or the like).
As is known, a sling is provided in the body using two large curved needles which are provided at each end of the sung, where the sling comprises a long mesh or tape. Each of the needles is carried on an insertion tool (which is basically a handle facilitating manipulation of the needles). The mesh or tape is usually made of knitted polypropylene (such as Prolene®). The mesh or tape is generally covered with a plastics sleeve or polythene envelope to aid smooth insertion, the mesh or tape having rough surfaces to aid retention in the body.
An incision is made in the anterior vaginal wall and the first of the needles is passed through the incision, past one side of the urethra, behind the pubic bone, through the rectus sheath and out through the lower anterior abdominal wall. Likewise, the second needle is passed through the incision, past the other side of the urethra, behind the pubic bone, through the rectus sheath and out through the lower abdominal wall. The needles are separated from their respective insertion tools and also from the mesh or tape such that only the tape and its plastics sleeve are left in the body, passing from a first exit point in the lower abdominal wall, through the rectus sheath, behind the pubic bone, under the urethra, back behind the pubic bone, back through the rectus sheath and out through a second exit point in the lower abdominal wall.
The plastics sleeve is then removed from the tape and the tape adjusted to a suitable tension (such that the tape provides a sling that passes loosely under the urethra, as described above) by maneuvering the free ends of the tape outside the exit points in the lower abdominal wall whilst the urethra is held using a rigid catheter inserted therein. The tape is then cut such that it just falls short of protruding from the exit points in the lower abdominal wall. The exit points and the incision in the upper vaginal wall are then closed by sutures. The tape is held in position by virtue of friction between the tape's rough edges and the surrounding body tissue (such as the rectus sheath and the body tissue behind the pubic bone) and subsequent natural adhesion of the tape with the body tissue as it re-grows around the mesh material.
Whilst highly effective in treating urinary incontinence, this procedure has a number of problems. One such problem is that the needles used for inserting the tape are comparatively large, with the needles having, for example, a diameter of around 5-6 mm and a length of around 200 mm. As well as causing concern for patients viewing such needles before or during the procedure (which is carried out under local anesthetic), this can also lead to a high vascular injury rate.
Similarly, the requirement that the needles exit the lower abdominal wall is disadvantageous due to the trauma to the patient in this area and pain of such abdominal wounds. A further disadvantage is that the tape comprises a relatively large foreign body mass to be retained within the patient and this can lead to related inflammation, infection translocation, erosion, fistula and such like.
Similarly, the nature of the large needles and tape, along with the tools required to insert these in the body, lead to the procedure having a relatively high cost.
In another known procedure which may be used to correct urinary incontinence, as shown in FIGS. 24 and 25, an incision is made in the perinea skin over a patient's first obturator foramen 134 and an incision 117 is made in the wall of the patient's vagina 116, a surgical instrument is inserted through the cutaneous incision, over the first obturator foramen 134 and passed through the obturator foramen (134) at a “safe” zone (138) close to the inferior pubic ramus (140), through the obturator muscle, and through the vaginal incision. A surgical implant is attached to the surgical instrument and the surgical instrument with the implant attached is retracted such that one end of the implant is pulled out of the body via the incision over the obturator foramen. A second incision is provided over the patient's second obturator foramen and the procedure repeated such that the implant is provided under the urethra 118 with a first end of the implant extending out of the first incision made over the first obturator foramen and a second end of the implant extending out of the second incision made over the second obturator foramen.
The requirement that the needles exit the body over the obturator foramen is disadvantageous due to the trauma to the patient in this area and pain of such wounds. A further disadvantage is that the implant comprises a relatively large foreign body mass to be retained within the patient and this can lead to related inflammation, infection translocation, erosion, fistula and such like. Furthermore, anatomical damage to nerves and blood vessels may occur during procedures which penetrate the obturator foramen.