HK1051798B - Transcutaneous device for treating female urinary incontinence by sub-urethral strip - Google Patents

Description

The present invention relates to urinary incontinence problems in women and in particular to stress urinary incontinence problems. The invention relates in particular to a percutaneous device for the treatment of stress urinary incontinence in women by a strap under the urethra.

These problems are currently treated during surgical procedures under local, regional or general anesthesia and involve the implantation of a band to provide tension-free support of the urethra.

With regional or local anesthesia, the surgeon can immediately check for the restoration of continence with the patient's participation.

Such intervention shall be carried out with appropriate equipment, including specialised instruments.

In particular, a strip which can be implanted under the urethral canal and a band around the band are known to be used for the treatment of urinary incontinence, and the band is removed from the band after the implantation.

A device is known for the treatment of female stress urinary incontinence, including: a flexible, elongated support of the urethra, comprising a band and a protective sheath enveloping the band flat, and a perforating needle with an active distal end and a proximal end connected to a first end of the flexible support.

The procedure for the treatment of incontinence is described in document US-A-5 899 909 as follows: the device described, which allows a strip to be placed under the urethra, has two special needles which are successively attached by screws to a reusable steel insert consisting of a handle and a threaded handle which allows each of the said needles to be manipulated successively.

Each end of the band-gain assembly is fixed to a trunk part of one end of the corresponding needle by means of a polymer ring retracted or glued.

The implantation of the strip is therefore carried out by inserting each needle from a short incision in the anterior vaginal wall, on either side of the central position of the urethra.

The needles, implanted successively with the manipulating rod, then climb up to bypass the bladder and pubic bone, and exit the body through incisions made in the abdominal wall in the suprapubic region.

The two overlapping halves of the garment facing the middle of the strap shall be removed by pulling on the extremes protruding from the suprapubian incisions.

Such a device requires the use of insertion-type handles and rigid intravesical catheter guide, specially designed for this type of surgery.

The known surgical procedure also has a drawback in that the needles are inserted into the anterior wall of the vagina to emerge in the suprapubian region. This pathway from bottom to top is not precisely controllable to bypass the base of the bladder.

The two accessories (handhold and rigid probe guide) must therefore be available to the surgical team during each operation, being washed, packed and sterilised before each use.

Another disadvantage of the known device is the difficulty of repeating the procedure with the same device when cystoscopy shows that the band-sheath has travelled the wrong way.

The belt-guard assembly must then be cut off and the device is no longer usable for another journey, and it may also no longer be sterile by being contaminated during these additional manoeuvres.

The object of the present invention is to remedy the disadvantages of the state of the art in order to obtain a different, easier, faster and safer operating technique (in comparison with the bladder and vessels).

Another purpose of the present invention is to develop a device for the treatment of urinary incontinence which can be readily reused if introduced into the body by an unoptimal route, which, according to the present invention, can only be exceptional in the case of very strong adhesions of the bladder to the pubic as a result of previous interventions.

According to the invention, the proximal end of the drill needle is connected to the first end of the flexible medium by means of an intermediate traction element, the second end of the flexible medium being free or extended by a complementary intermediate traction element.

In a way of making the description according to the invention, the protective sheath completely covers the strap including its first and second ends.

According to one embodiment of the invention, the sheath is cut into two parts which can be separated by sliding in two opposite directions from the band, the said device having a cutting medium between the two central and adjacent ends of the sheath.

According to another embodiment of the device according to the invention, it consists of a thread arranged approximately perpendicular to the longitudinal axis of the sheath, so as to cut the sheath when a pull is applied to the sheath.

According to one design of the device according to the invention, the sheath is made of a fluoro-polymer thermosetting material.

According to a method of manufacture of the device according to the invention, the strip is formed from a macro-porous knitted material. According to one embodiment of the invention, the strip has a central absorbable hydrophilic film which reduces the risk of adhesion or erosion of the urethra.

According to one embodiment of the device according to the invention, the puncture needle has a continuously adjacent curved part with a substantially straight part terminating at its proximal end.

According to one embodiment of the invention, the intermediate traction element is a traction lace.

The device according to the invention has a tip on which the sheath is attached by thermal retraction and on which the tensioning lace is attached.

In a manufacturing process according to the invention, the length of the drawstring is approximately equal to the length of the flexible medium.

According to a preferred method of manufacture of the device according to the invention, the intermediate traction element is tubular.

In a manufacturing process for the device according to the invention, the intermediate traction element and the punching needle are joined by screwing.

In one embodiment of the device according to the invention, the traction element consists of two parts of substantially the same length, which are bolted together and assembled to each other in a removable manner, e.g. by screwing with a connection.

According to a method of manufacture of the device according to the invention, the punching needle is unique.

Other features and advantages are also shown in the following detailed, non-limiting description, given by reference to the attached drawing in which: Figure 1 represents a cut-out view of the flexible medium of the device in accordance with the invention,Figure 2 represents a view from above, with partial tearing of the flexible medium shown in Figure 1.Figure 3 partially represents another example of the implementation of the flexible medium in Figure 2,Figure 4 represents a partial view of a device in accordance with the invention,Figures 5 and 6 represent details of Figure 4,Figures 7 and 8 represent another mode of implementation of the flexible medium of the device in accordance with the invention,Figure 9 represents a partial view of another mode of implementation of the device in accordance with the invention,Figures 11a, 11b, 11 and 11 in Figure 19 represent a detailed and schematically representative of the device in accordance with the invention,Figure 20 represents the device in accordance with the invention,Figure 20 represents the device in accordance with the invention,Figure 11 and Figure 12 represent the device in accordance with the invention.

The device partially represented in Figures 1, 2, 3 and 4 comprises an elongated flexible medium 1 usually consisting of a composite strip.

The flexible medium 1 is shown only partially and not in its entirety.

The first end 1a of the flexible medium 1 is likely to be connected to an intermediate traction element 2 (see Figure 4) and the second end 1b is free or extended by an additional intermediate traction element (not shown).

The device according to the invention also has a punching needle 3, e.g. stainless steel, connected to the intermediate traction element.

The flexible means 1 comprises a protective sheath 5 wrapping a strip 6 flat.

The single needle 3 has an active distal end 3a and a proximal end 3b, connected to the first end 1a of the flexible medium 1.

The proximal end 3b of the drill needle 3 is connected to the first end 1a by means of the intermediate traction element 2.

The distal end 3a is at the end of a continuously adjacent curved part with a substantially straight part ending at the proximal end 3b.

The punching needle, for example, has a diameter of 3.5 mm in its curved part.

The proximal end 3b shall also be fitted with a means of attachment to enable the coupling to be made with the intermediate traction element.

The protective lining 5 completely encloses the strap 6, including its first end 6a and its second end 6b.

The material of the sheath 5 is chosen so that it is perfectly watertight to completely isolate the strip 6 intended for implantation into the patient's body from skin and mucous contact during the implementation of the implantation pathways into the patient's body.

The sheath 5 may also have low coefficient of friction properties, which are then found on the inside and outside of the sheath 5, so as to ensure both good separation from the strip 6 and a reduction in friction inside the patient's body when the flexible medium 1 is pulled.

The strip 6 is preferably 6 to 14 mm wide, preferably 10 to 12 mm, and 30 to 50 cm long, preferably around 40 cm.

The strip 6 is preferably formed from a macro-porous knitted material.

The latter consists, for example, of a knit polypropylene monofilament of a thickness of between 0.12 and 0.16 millimetres and is composed of two sheets of two threaded pass-bars each, one full-pass and one empty pass, these two bars being moved symmetrically in open meshes according to the following scale:

The strip 6 is cut in length in the direction of the knitting chain.

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Strip 6 has interesting advantages, in particular a low emission of particles when stretched and a tiles that only appear under high stress (6N).

The 5th strip is preferably cut into two parts 51, 52, which can be separated by sliding in two opposite directions from the 6th strip.

The device according to the invention has a cutting medium 15 for this purpose, situated in the centre of the sheath 5 and having both ends joined with the corresponding and adjacent centre ends 5c, 5d of the sheath 5.

The material of the cutting medium 15 shall be selected from thermoplastic materials approved for surgical applications.

The connection between the centre ends 5c and 5d of the two parts 51 and 52 respectively and the cutting core 15 is made by any means which can make the sheath 5 watertight.

The cutting medium 15 compresses a flat slot 15a through it from one longitudinal end to the other, for the free passage of strip 6.

The cutting medium 15 can be replaced in a way represented in Figures 7 and 8 by an adhesive sleeve 16a that covers both cutting parts 51 and 52 of the sheath 5. This sleeve is weakened, for example, by a partial cut into dots or a line of weakening of the sheath 5. The adhesive sleeve 16a made with a soft material that adheres closely to the central ends 5c, 5d also has a pre-cut tongue 16b to facilitate the tearing of the said sleeve 16a, and consequently the separation of sheath 5 into both parts 51 and 52.

According to another embodiment of the device according to the invention, the monobloc sheath 5 incorporates a 16c wire arranged appreciably perpendicular to the longitudinal axis of the sheath 5 so as to cut the sheath 5 when a pull is applied to the sheath 16c. An example of this is shown in Figure 3.

The sheath 5 is thus sectionable in the central zone 1c of the flexible medium 1 so as to release the strip 6 into the patient's body.

The intermediate traction element is, according to one embodiment of the invention, e.g. made with a traction lace 2 as shown in Figure 4.

The device of the invention also has a tip 4 on which the sheath 5 is thermo-retracted, and the sheath 5, particularly its first end 5a, is thus thermo-retracted tightly on tip 4.

As shown in Figure 2, the tip 4 has anchorage notches 4a into which the thermo-retracted material constituting the sheath 5 is attached.

The advantage of the flexible medium 1 is that it has a 4b knot (see Figure 4) outside the sheath 5. This 4b knot is for example a closed loop and may have a 4c tip, if necessary, to cut through and attach an end of the 2 or any other intermediate traction element.

For example, the 4b tie-tie is made in a monoblock shape at the 4th tip. The latter can also be of a considerably flat and partially truncated shape so as to achieve continuity between different thicknesses of the 2nd tie-tie and the 1st flexible medium. The latter has a wider width than the 2nd tie-tie.

Figure 4 shows a schematic example of the manufacture of the device according to the invention.

The needle 3 comprises the proximal end 3b, on which the first end 2a of the tension lace 2 is attached. The latter has, for example, at each of its ends 2a and 2b a loop 2c (see Figures 5 and 6 respectively), obtained by ultrasonic welding, sewing or any other means.

One of these loops 2c is mounted on the proximal end 3b of the needle 3, while the other is mounted in the eyepiece 4b.

In the operating mode, it is thus possible to attach the end 2a of the drawbar eyelet 2 to the eyelet 4b either by means of the jointed tip 4c of the eyelet 4b or simply by making a point in the wire on the closed loop of the eyelet 4b.

The device according to the invention thus has, for example, a traction lace 2 the length of which is, for example, substantially equal to the length of the flexible medium 1, i.e. a length between 30 and 60 cm. Such dimensions or lengths of the traction lace 2 allow, when referring to the operating mode, to avoid engaging the flexible medium 1 in the body before ensuring that the path taken by the needle 3 and the traction lace 2 is optimal.

Alternatively, the second end 1b of the flexible medium 1 may be provided with an intermediate supplementary traction element, such as an additional lacing, as described above in reference 2.

A complementary and solid traction lacing 2 of the free end 1b, which may also have a tip 4 for this purpose, allows traction to be performed in the opposite direction to its introduction on the flexible medium 1 and to pull it out of its path, in case of poor penetration.

According to another method of manufacturing the device according to the invention, as shown for example in Figure 9, the intermediate traction element is a tubular element 20.

The tube element 20 is preferably semi-rigid so that it can be screwed on a threaded end 3c, which is connected to the proximal end 3b of the needle 3.The other end of the tube element 20 is connected, for example by screw, to the flexible medium 1, which has a threaded end 30 which is connected to the sheath 5, for example by thermo-retraction.The end 30 has a complementary threaded part 30a for this purpose (see Figures 7 and 8).

The flexible medium 1, the tubular element 20 and the two parts 3a, 3b of the drill needle 3 can thus be assembled removably by screwing.

Other known removable means of attachment or hooking may also be appropriate for the purpose of the present invention.

The tubular element is, for example, made up of several parts of substantially the same length, e.g. 20 and 41, which are bolted and joined together by screws in a removable way.

The coupling 40 shall consist of two components, namely an internal coupling chuck 42 and an external clamping socket 43.

The chuck 42 has a threaded nipple 42b engaged in the tubular element 41 part on one side and a 42a head with 42c crests on the other side, intended to be engaged in the tubular element 20 part, as shown in Figures 11b and 11c. The shape and dimensions of the crests 42c tend to oppose the separation of the tubular element 20 part from the chuck 42.

Each chuck 42 is connected to a socket 43 engaged on the part of tubular element 41 so as to enclose a part of that part 41 between the threaded nipple 42b and the socket 43.

The latter is also fitted with a 43a screw-in at the front, which is inserted by screwing into the material constituting the rear end of section 20d.

First, one end of the tube element of part 41 is pointed at the tip of 42b; then the socket 43 is brought to this end of part 41, with the constituent material enclosed between the thread of the tip 42b and the sleeve 43, the latter also enclosing the rest of the chuck 42 except the protruding nipple 42a.

The assembly of the two parts 20 and 41 of the tubular element is carried out by engaging the nipple 42a at one end of said part 20 (Figure 11b) and then screwing the end of the socket 43 on the outer periphery of said part 20 (Figure 11c).

The device according to the invention enables a treatment procedure to be implemented in women with stress urinary incontinence, which will be described below, and which allows the insertion of the strip 6 into the patient's body.

The processing process shall consist of the following steps: (a) form an opening 103a in the anterior vaginal wall 103, (b) make two small incisions above the pubic 106, (c) use the perforating needle 3 connected to an intermediate traction device 2 or 20 to create a first passage around the pubic bone 105 and leading into the opening 103a formed in the anterior vaginal wall 103, (d) use the perforating needle 3 connected to an intermediate traction device to create the second passage around the pubic bone 105 and leading into the opening 103a formed in the anterior vaginal wall 103. (e) check cystoscopically that the separation of these portions has not caused the second traction to occur between the urethra or urethra, (e) pass the two openings between the vaginal opening 103, (e) remove the first and second traction devices from the anterior vaginal wall 103, (f) remove the first and second traction devices from the anterior vaginal wall 103, (g) remove the second traction device 103, (i) remove the second and third traction devices from the anterior vaginal wall 103, (v) and (i) remove the second and third traction devices from the anterior vaginal wall 103, (v) and (i) remove the second and third traction devices from the anterior vaginal wall 103, (v) and (vi) remove the first and second traction devices from the anterior vaginal wall 103, (vi) and (vi) remove the first and second and second traction devices from the anterior vaginal wall 103, (vi) and (vi) remove the first and second and second and third and third and third traction devices from the first and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and third and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and fourth and

According to one use case of the invention, the procedure consists in guiding the paths of the perforating needle 3 along the posterior surface 105a of the pubis, by contact with the surgeon's finger 50 inserted through the opening 103a, formed in the anterior vaginal wall 103, to the lower edge 105b of the same side of the pubis 105.

In a mode of operation of the device according to the invention, the flexible medium 1 is attached to the intermediate element 2 or 20, after the verification as described in step (e).

According to a method of operation of the device according to the invention, the opening 103a in the anterior vaginal wall 103 is vertical.

The procedure involves inserting a 60° FOLEY urethral tube into the patient.

A conforming treatment process using the device of the invention uses two intermediate traction elements 2 or 20, connected end to end during step (f).

In another treatment using the device of the invention, the punching needle 3 is separated from the intermediate traction element 2 or 20, after the verification according to step (e) has been carried out and the flexible medium 1 has been introduced according to the first path.

All the previously defined steps are now described with a device in accordance with Figures 7 to 11 and the description relating thereto.

The first step (a) is shown in Figure 12. The patient is placed in a gynecological position and a sterile operating area is established. A urethral balloon probe 60 is placed in bladder 101 and is connected to a sterile slide pocket to empty and flatten bladder 101. A short vertical incision 103a, not more than 30 mm long, is made in the middle of the vaginal wall 103, centered in the central third of the urethral canal 100 leading to urinary metatarsum 100a. Each lip 103b of the vaginal incision 103a is detached from the underlying tissue using scissors 71 and appropriate instruments 70, as shown in Figure 13.

The detachment is carried out until the surgeon's index 50 introduced by the resulting opening 103a can reach the lower edge 105b of pubis 105, outside urethra 100 and periurethral tissue (Figure 14).

Next, a very small skin incision 106, 107 less than 10 mm long is made in the abdominal skin immediately above pubis 105, on either side of the midline and about 20 mm from it, to allow the needle 3 to pass through the skin by shaving the posterior 105a side of pubis 30 in the direction of the vagina 104.

The surgeon's index 50 is inserted into the vaginal opening prepared by detachment, and the active distal end 3a of the needle 3 follows a path to come into direct contact with this index 50. The path of the perforation needle 3 is therefore perfectly controlled. The needle 3 can then be removed through the vaginal opening 103a and the bladder 101 is completely protected from needle injury.

The end of the intermediate traction element, e.g. the tubular element 20, protrudes behind the needle 3 through the vaginal opening 103a. This end of the traction element 20 is, for example, unscrewed from the proximal end 3b of the needle 3 and separated from the latter by the S-arrow in Figure 15.

The needle 3 is then passed through the second passage (left side, Figure 16) in the same way as the first (right) passage. Once the distal part 3a of the needle 3 is well outside the vaginal opening 103a, it can be detached by unscrewing its proximal portion 3b. This separation is shown by the T arrow in Figure 16.

The proximal portion 3b is long enough to protrude during the percutaneous incision 107.

As a variant of the invention, the proximal portion 3b may be extended by an additional tubular element 20 protruding out of the abdominal incision 107.

The next step is to connect the end of the tube 20 traction element on the first track to the proximal section 3b or to the additional tube 20 on the second track.

The connection is made by means of the connector 40 shown in Figure 17.

The proximal portion 3b is then pushed out through the abdomen by pulling in the direction of the V-arrow shown in Figure 18.

Before the soft medium 1 enters the patient's body, the tubular element 20 thus forms a loop around the urethra and its two ends emerge through the two abdominal skin incisions 106 and 107 (Figure 18) respectively.

The urethral tube 60 is then removed and a cystoscopy is performed to check for bladder perforation.

Once the check is completed, the end of tube 20 leading out of abdominal incision 106 is screwed to the threaded end 30a of the soft medium 1 (gain 5 plus strip 6), and the assembly is pulled (arrow V of line 18) through the right and left tracts to position soft medium 1 under the urethra 100. When this positioning corresponding to step (g) is completed, the ends 1a, 1b of soft medium 1 emerge from the abdominal incisions 106, 107, as shown in Figure 21.

Then separate sheath 5 from strip 6 by cutting sheath 5 into its central zone 1c and removing each of the halves 51 and 52 thus obtained by the corresponding abdominal incision 106, 107 in accordance with step (h) (W arrows in Figure 19).

The strip 6 is then released, positioned and adjusted under the lower face of urethra 100, usually in a central position, without tension and without crushing, as shown in Figure 20.

After removal of the sheath 5 through each abdominal incision 106 and 107, section at the base of the abdominal wall, with the parts of the strip 6 protruding out from the abdominal incisions 106 and 107, leaving these parts in a subcutaneous site.

The incisions are closed using conventional methods.

The strip 6 conveniently bypasses pubic bone 105 along its pelvic or deep face, to the controlateral abdominal wall.

The resulting vaginal incision 103a is then closed in the vaginal wall 103 after verifying the final position of strip 6 under urethra 100.

Alternatively, the traction lace 2 is also suitable for the application of this method.

The method used is remarkable in that it is a percutaneous surgical technique, since the size of the abdominal skin incisions is minimal, just for the needle passage, and the paths taken by needle 3 are from top to bottom, i.e. entering through abdominal incisions 106 and 107, and exiting through the corresponding vaginal opening 103a, previously determined and prepared.

This has a huge safety advantage in relation to the risk of perforation of the bladder 101 on the one hand and of the iliac vessels on the other.

This is a considerable advantage over the known surgical technique, whereby a path control can be performed by cystoscopy.

If the path is not suitable, the intermediate traction element 2 or 20 may be removed to make a second path through the abdominal cut 106 without introducing the flexible medium 1 into the body.

All the components of the device conforming to the invention can therefore be reused in case of improper handling or if the path inside the patient's body is to be improved or optimized.

In addition, the described surgical technique requires neither the use of a needle inserter nor an endovegetable rod to remove bladder 101 and urethra 100 at each passage of needle 3 on a top-down path. This is an interesting simplification, since the surgical technique presented in the present state of the art requires the use of a double endovegetable rod, i.e. after each passage of each of the two needles making a bottom-up path.

It is noted that the device according to the invention is a percutaneous device, which is advantageous over the known device which enters through the vaginal mucosa and exits through the skin into its abdominal suprapubic region.

It is noteworthy that the extreme simplicity of the device in accordance with the invention contributes not only to reducing its cost and number of components, but also to increasing patient safety and quality of the result when implementing the surgical technique described in the present invention.

The control of the effect on the continence and the adjustment of the tension of the strap 6 are not justified for two reasons: continence in the reclined position is not comparable to the standing position and the effectiveness of the strap is explained not by a tightening effect (which may lead to stenosis) but by a supporting supporting effect.

The operator shall also select the position of the strip 6 in relation to the urethral tube 100 according to the clinical case under consideration.

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Claims (16)

1. Device for treating urinary stress incontinence in women, comprising:

   - a flexible and elongate means (1) comprising a tape (6) for supporting the urethra (100) and a protective sheath (5) lying flat and enveloping said tape (6);

   - a puncturing needle (3) with an active distal end (3a) and a proximal end (3b) connected to a first end (1a) of the flexible means (1),

   characterized in that the proximal end (3b) of the puncturing needle (3) is connected to the first end (1a) of the flexible means (1) by virtue of an intermediate traction element (2, 20), the second end (1b) of the flexible means (1) being free or extended by an additional intermediate traction element.
2. Device according to Claim 1, characterized in that the protective sheath (5) completely envelopes the tape (6), including its first and second ends.
3. Device according to Claim 1 or 2, the sheath of which can be split into two parts that can be separated by sliding them in two opposite directions relative to the tape (6), characterized in that it comprises a splittable means (15) between the two central and adjacent ends (5c, 5d) of the sheath (5).
4. Device according to Claim 1 or 2, the sheath of which can be split into two parts that can be separated by sliding them in two opposite directions relative to the tape (6), characterized in that it comprises a filament (16c) arranged roughly at right angles to the longitudinal axis of the sheath (5), so as to cut said sheath (5) when traction is exerted on said filament (16c).
5. Device according to any of Claims 1 to 4, characterized in that the sheath (5) is made of a fluoropolymer-based heat-shrinkable material.
6. Device according to any of Claims 1 to 5, characterized in that the tape (6) is formed from a macroporous knitted material.
7. Device according to any of Claims 1 to 6, characterized in that the tape (6) in its central region has a resorbable hydrophilic film reducing the risk of adhesion to or the risk of erosion of the urethra (100).
8. Device according to any of Claims 1 to 7, characterized in that the puncturing needle (3) has a curved part continuously adjacent to a roughly straight part ending in its proximal end (3b).
9. Device according to any of Claims 1 to 8, characterized in that the intermediate traction element is a traction lace (2).
10. Device according to Claim 9, characterized in that it comprises an end piece (4) onto which the sheath (5) is heat shrunk and to which the traction lace (2) attaches.
11. Device according to Claim 9 or 10, characterized in that the traction lace (2) has a length roughly equal to the length of the flexible means (1).
12. Device according to any of Claims 1 to 8, characterized in that the intermediate traction device is a tubular element (20).
13. Device according to Claim 12, characterized in that the tubular traction element (20) and the puncturing needle (3) are assembled by screwing.
14. Device according to Claim 12 or 13, characterized in that the tubular traction element consists of two parts of roughly the same length, placed end to end and joined together removably, for example by screwing using a coupling (40).
15. Device according to any of Claims 1 to 14, characterized in that the puncturing needle (3) is the only puncturing needle.
16. Device according to any of Claims 1 to 15, characterized in that the tape (6) is cut from an open knit made up of two layers formed by two threaded guide bars each - one full guide and one empty guide - these two bars being moved symmetrically for open mesh.