HK1050469A - Surgical instrument - Google Patents

Description

Surgical instrument

Technical Field

The present invention relates to a surgical instrument and method for placing an elongated member on a patient, and more particularly, to the field of obstetrics and gynecology, and more particularly, to an instrument and method for treating female urinary incontinence.

Technical Field

Female urinary incontinence typically occurs as a result of degeneration or damage to the musculature and ligaments in the pelvic region. As a result, urine flows unintentionally out of the urethra due to the patient's lack of control of pelvic muscles (particularly the urogenital diaphragm and the urethral ligaments). This condition can be cured by building some form of artificial ligament between the abdominal muscles and the urethra, which passes behind the pubic bone.

The applicant is aware of two prior art patents, discussing the same subject matter as the present invention, namely us 5112344 (petiolus) and us 5899909 (kralon). Us patent 5112344 describes a method and apparatus for treating female urinary incontinence. The surgical instrument for applying a filamentary element into the body includes a tubular shaft having a handle at one end and a flexible needle slidably receivable over the shaft and adapted to receive a filamentary element at one end. A method of treating female urinary incontinence comprises looping a filamentary element between the vaginal wall and the rectus abdominus sheath, the loop being located at the anterior wall of the abdominal cavity whereby the filamentary element gathers on each side of the urethra, adjusting the size of the loop to bring the vaginal wall and urethra into correct spaced relation to the pubic bone, allowing growth of scar tissue between the vaginal wall and the anterior wall of the abdominal cavity at the pubic symphysis, and removing the filamentary element.

The clara patent, U.S. patent 5899909, also describes a surgical instrument and method for treating female urinary incontinence. The instrument comprises a shaft having a handle at one end and two curved needle-like elements which are coupled together at one end, each element having at one end a string to be implanted in the body. The elements may be connected together with one end to the rod at one end and the other end to form the end of a curved rod, the elements being passed into the body via the vagina, each element being dimensioned to extend from the inside of the vaginal wall, around the back of the pubic bone, to the outside of the abdominal wall. When the method is performed, the tape is passed into the body through the vagina, initially on one side of the urethra at one end and then on the other side of the urethra at the other end, forming a loop around the urethra between the urethra and the vaginal wall. The tape extends around the pubis, through the abdominal wall and is tightened. The tape ends are then cut at the abdominal wall so that the tape is implanted and left in the body.

Brief description of the invention

In its broadest form, the present invention provides a surgical instrument for placing an elongate member within a patient, the instrument comprising:

an elongate shaft defining an internal passage, said shaft having a cutting tip formed at one end thereof and operating means formed at the other end thereof, the shaft including the operating means being of substantially uniform cross-section along its entire length such that the shaft is capable of entering and passing through the body of a patient, the internal passage being adapted to guide said elongate member into the patient when the apparatus is located therein.

In a preferred form of the invention there is provided a surgical instrument for placing a filamentary element in a female patient to form a circumferential cable or loop around the urethra extending through the back of the pubis to the abdominal wall, the instrument including:

a generally arcuate, curved tubular shaft defining an internal passage, said shaft having a cutting tip formed on one end and operative attachment means formed on the other end, the shaft being of substantially uniform cross-sectional diameter along its entire length;

a handle non-rotatably connected to the operating attachment of the shaft;

a flexible wire element insertable through both ends of said shaft and adapted to be withdrawn through said internal passage at least when the handle is removed from the shaft.

According to another insight of the present invention, there is provided a surgical instrument for placing a wire-like element in a female patient to form a circumferential cable or loop around the urethra, extending around the back of the pubis to the abdominal wall, said instrument comprising:

a generally arcuate, curved tubular shaft defining an internal passage, said shaft having a cutting tip formed on one end and an operating attachment formed on the other end;

a handle, which is non-rotatable relative to the shaft when mounted on the shaft, and is connected to an operation attachment of the shaft;

a flexible wire element insertable from both ends of said shaft and through said internal passage, adapted to be used to withdraw one end of said wire element through said internal passage;

the tubular shaft is curved such that the shaft lies substantially in a single plane;

the cutting tip, when formed, has a transverse angle at least in a plane substantially perpendicular to the single plane and at an acute angle to the axis of the shaft. The leading edge of the tip is preferably located radially inward of the curved tubular shaft.

The acute angle is preferably between 20 ° and 70 °, which may be about 45 °. Preferably, the front end of the shaft is curved.

The cutting tip has two inclined surfaces that are inclined to each other at an acute angle. The two inclined surfaces preferably intersect along a line perpendicular to the axis of the shaft.

In one arrangement, the operating attachment includes threads formed on an outer surface of the shaft. Preferably, the shaft tapers towards the working attachment to form a smooth transition between the cylindrical portion of the shaft and the working attachment.

Said internal passage includes one or more notches or detent formations at or towards said other end of the shaft with which said handle engages to ensure said non-rotatable connection.

The handle preferably includes a hand gripping portion which is substantially larger than the shaft portion, the shaft portion being adapted to be axially aligned with the said other end of the tubular shaft when the handle and the tubular shaft are operatively connected. The shaft portion has a tapered distal end adapted to be inserted into the internal passage of the shaft. Preferably, the handle includes an annular flange on said shaft portion adapted to engage said other end of said tubular shaft, a coupling nut slidably mounted on said shaft portion between said annular flange and said handle portion, said coupling nut adapted to engage threads on the tubular shaft to couple the tubular shaft to the handle.

Preferably, the tubular shaft has a generally arcuate portion at a distal end thereof, toward the other end thereof, and a generally straight section toward the handle end thereof.

The tubular shaft has a series of apertures through the wall between the interior passage and the exterior of the shaft, the apertures being spaced along the length of the shaft.

According to another insight of the present invention, there is provided a surgical instrument for placing a wire-like element in a female patient to form a circumferential cable or loop around the back of the pubic bone and out of the abdominal wall at the anterior surface of the vaginal wall, the instrument comprising a curved tubular shaft defining an internal passage, the shaft having at least one aperture through the wall between the internal passage and the outside of the shaft.

Preferably there is a series of such apertures spaced along the length of the shaft. The apertures are preferably located on the outwardly convex side of the shaft. The shaft preferably has a cutting tip at one end and operating attachment at the other end, the shaft having a generally arcuate portion at the end remote from the handle toward the tip, a straight section toward the handle, and apertures at least in the generally arcuate portion.

According to another insight of the present invention, there is provided a method of introducing a filamentary element into a female patient, the method forming a loop or loop extending around the urethra to the anterior surface of the abdominal wall, said method comprising the steps of:

a) inserting an arcuate shaft having a longitudinally extending internal passage into the patient through the anterior surface of the vaginal wall, so as to pass through one side of the urethra between the pubic bone and the bladder, through the abdominal wall, and out of the patient;

b) threading a wire-like member along the internal passage from one end or the other thereof such that the distal end of the wire-like member exits the distal end of the shaft;

c) attaching a thread-like element to the end of the thread-like element, and extracting the thread-like element and the thread-like element through the shaft;

d) withdrawing the shaft from the patient leaving the filamentary element in place in the patient;

e) inserting the shaft into the patient through the anterior surface of the vaginal wall, such that it passes through the side of the urethra between the pubic bone and the bladder, through the abdominal wall, and out of the patient;

f) repeating steps b), c) and d), extracting the filiform element through the shaft; and is

g) The shaft is withdrawn from the patient leaving the filamentary elements in place to form a loop extending around the urethra to the anterior surface of the abdominal wall on the opposite side of the urethra.

The shaft may be tubular or U-shaped in cross-section with a longitudinal slot or groove along the length of the shaft.

The above method may be performed using a single incision or a pair of incisions. The double incision method involves making a pair of paraurethral incisions in or very near the anterior vaginal groove. A blunt incision is made between the urethra and the vaginal wall to create a tunnel extending from each vaginal incision. The end of the filamentary element proximal to the vagina, through the passage, exits the second of the two incisions before proceeding to step (e). Step (f) operates through the second of the two incisions.

It is desirable to allow linear elements to be inserted into the hollow shaft from both ends of the shaft as desired.

Preferably, the shaft is fitted with a detachable handle, the shaft having a substantially uniform outer diameter along its entire length, allowing the shaft to be withdrawn from the patient from outside the abdominal wall once the handle is removed.

The above, as well as further characteristics of the invention, will become apparent from the following description of an embodiment, given by way of example. In the description, reference is made to the accompanying drawings, but the specific features shown in the drawings should not be considered as limiting the invention.

Brief Description of Drawings

Fig. 1A and 1B show the front end of a prior art surgical instrument of the type described in us patent 5112344.

Fig. 2 shows a perspective view of the front end of the surgical device according to the invention.

Fig. 3 shows a discrete perspective view of the elements required for performing a procedure using the surgical instrument of the present invention.

Fig. 4-6 illustrate the manner in which the surgical instrument actually operates during various stages of the procedure.

Fig. 7 shows another embodiment of the present invention.

Fig. 8 shows another form of the front end of the surgical device of the present invention.

Figure 9 shows another form of connection arrangement between the shaft and the handle.

Fig. 10 illustrates a side view of another embodiment of a surgical device according to the present invention.

3 fig. 3 11 3 shows 3 a 3 perspective 3 view 3 of 3 the 3 portion 3 of 3 fig. 3 10 3 between 3 lines 3 a 3- 3 a 3 and 3 b 3- 3 b 3. 3

3 fig. 3 12 3 shows 3 a 3 cross 3- 3 sectional 3 view 3 along 3 the 3 line 3 a 3- 3 a 3 in 3 fig. 3 10 3. 3

Fig. 13 shows a view similar to fig. 12, however, of yet another embodiment of the present invention.

Fig. 14 shows a view similar to fig. 12, however of a further embodiment of the invention.

Fig. 15 shows a side view of another form of the cutting tip of the present invention.

Fig. 16 shows an end view of the cutting tip shown in fig. 15.

Detailed Description

Referring to fig. 2-6, a surgical instrument 10 according to the present invention is shown in detail. The instrument 10 includes a curved shaft 12 having a cutting tip 14 formed at a leading edge and an operating attachment 16 formed near an opposite end 17. As is clearly shown in the figures, the cutting face of the cutting tip 14 is at an angle to the axis of the shaft, the correct profile of which will be described in more detail below. The shaft 12 is hollow and defines an internal passage 18, the purpose of which will be described in more detail below.

A handle 20 is attached to the end 17 of the shaft 12, the handle 20 including a handle portion 22 which, in use, is held by a surgeon performing a surgical procedure using the present instrument 10. The handle 20 also includes a shaft portion 24 having a tapered front end 26 and interlocking formations 28 which engage corresponding interlocking formations 30 formed on the inner surface of the channel 18. The interlocking formations 28 and 30 are engaged to ensure that the handle is not rotated after it is attached to the shaft 12, so that the surgeon can control the orientation of the shaft as it is inserted into the body cavity by carefully twisting the handle 22 during the procedure. The coupling nut 32 is slidable along the shaft portion 24, which is shown in a retracted position in fig. 3. An annular flange 34 is formed on the shaft portion 24 of the handle. When the reducing portion 26 of the handle is fully inserted into the shaft 12, the flange 34 will abut the end 17 of the shaft, and the coupling nut 32 will be screwed onto the threads 16, thereby securely coupling the handle 20 to the shaft 12. To remove the handle from the shaft 12, the coupling nut 32 is loosened from the threads 16, allowing the handle to be withdrawn from the shaft 12. It is important that the procedure be relatively simple to perform, since during surgery the handle will typically be removed from the shaft 12, while the shaft 12 is still within the patient. Thus, the coupling nut 32 can be tightened and loosened with the fingers.

It should be noted that, particularly from fig. 3, the shaft 12 is arcuate with the portion thereof near the front end 14 being the most pronounced curved portion. The shape of the shaft is selected so that the shaft can pass behind the pubic bone through the anterior surface of the vaginal wall and out through the abdominal wall. The radius of curvature is chosen with this objective in mind. When the shaft is inserted through the body cavity, bypassing the pubic bone, the front end of the shaft will be next to the pubic bone while the tip is kept away from the bladder.

The shaft portion near the handle is relatively straight, while the front portion of the shaft is significantly curved. The curvature lies in a single plane, i.e. in use the plane of curvature will be substantially coplanar with the plane of the sagittal suture of the patient.

The cutting tip 14 has a cutting surface at an angle to the axis of the shaft, the tip lying in a plane perpendicular to the aforementioned plane of curvature. The forwardmost tip 36 of the cutting tip is located radially inwardly 38 of the curved shaft, with the remainder of the cutting tip sloping rearwardly from the tip 36 at an acute angle to the axis 40 of the shaft. The cutting tip 14 lies in a plane which intersects the shaft axis 40 at an acute angle α of between 20 ° and 70 °, but preferably approximately 45 °. The shape of the tip, particularly the radially inner tip 36, always keeps the sharp front end of the tip away from the bladder, thereby reducing the likelihood of the tip 36 puncturing the bladder. The angle of the cut always pushes the bladder away from the tip 36, further avoiding the possibility of puncture.

Although in this specification reference is made to a "cut" at an angle to the axis of the shaft for a cutting tip, it will be understood that the production process does not require such an actual cutting operation and any production process that provides a cutting tip with an surgically sharp angle is considered to fall within the scope of the term "cut".

In use, at the start of a procedure, shaft 12 is attached to handle 20 in the manner described above, inserted into the patient, typically via the vagina, from a position inward of the urethra and bladder junction, and the cutting tip is passed into the body cavity, through the side of urethra 44 between bladder 42 and pubic bone 46. The cutting tip is then passed out of abdominal wall 48. The fully inserted position of the shaft is shown in figure 4.

Patients requiring a two-incision procedure will make two paraurethral vaginal incisions in or very near the vaginal canal. A blunt dissection is made between the urethra and the vaginal wall to create a tunnel extending between the two paraurethral incisions. The two incisions and tunnels will typically be formed prior to the first insertion of the shaft into the body cavity of the patient.

After the shaft is fully inserted, the handle 20 is removed from the shaft 12, while the shaft 12 remains stationary during this period of time within the body cavity. A linear element 50 is passed through the internal passage of the shaft in the manner shown in figure 5. It is important to note that the threadlike element 50 may be threaded into the shaft 12 from either end of the shaft 12. The thread-like element 50 has a small gripping portion 52 on one end and a hook 54 on the opposite end. The hook 54 is intended to grip a filiform element 56, which filiform element 56 is equipped for this purpose with a loop 58. The filamentary element 56 is typically made of a material such as "pluron" (tm) or "phillips" (tm), which is manufactured by eicoko. The threadlike element 50 is then pulled out of the shaft 12, dragging the threadlike element 56 thereon, drawing the threadlike element 56 through the hollow shaft 12. With the filamentary element 56 fully in place, the shaft 12 will be withdrawn from the patient. It is important to note that the shaft 12 may be withdrawn from the patient's ventral side or the patient's vaginal side, as the shape and configuration of the shaft is designed for this purpose. The wire-like element 50 may of course also be used to push the wire-like element through the shaft.

It should be noted that the shaft 12 has a tapered portion 60 near its trailing end 17 which provides a smooth transition between the cylindrical central portion of the shaft and the threaded end 17. The design of the tapered portion 60 is such as to allow the shaft to be pulled forward through the patient's body without causing any further tissue damage to the patient. The taper angle of the tapered portion should be made small, i.e., about 5 ° or less. Another possible connection configuration does not substantially result in an increase in diameter. For example, an internal thread configuration is one possibility. Other options are discussed below.

When the double incision approach is preferred, the vaginal end of the wire will be guided through the aforementioned tunnel and out of the second incision. The handle is then reattached to the shaft, which is inserted back into the patient's body, passing once again between the bladder 42 and the pubic bone 46 on the opposite side of the urethra, and out the abdomen 48. Thereafter, the handle is removed from the shaft and, working on the abdominal side of the patient, the thread-like element is fed through the hollow shaft. A hook on one end of the linear element is then used to capture the wire, pulling the wire through the hollow shaft and out the abdominal side of the patient. The hollow shaft is then removed from the ventral side of the patient, leaving a loop of U-shaped wire-type material in the patient's body that extends around the urethra. Such a procedure is not possible with respect to the prior art instruments described above.

In most procedures, the shaft is withdrawn from the ventral side of the patient during the second phase of the procedure. In the case of withdrawal from the ventral side of the patient, the end 17 of the shaft needs to pass through the patient's body, which is why a smooth taper 60 (see above) is provided, and the fact that the diameter of the thread 16 is not significantly larger than the central or cylindrical portion of the shaft.

Once the filamentary element has passed twice through the body cavity of the patient, the free end thus created will be cut off. A U-shaped loop will be left, generally permanently, in the patient forming an artificial ligament around the urethra, significantly improving urinary control for the patient.

The wire may be left permanently in the patient or may be removed at some later stage, both of which are discussed above in the prior art.

It should be noted that the shaft 12 is provided with a series of small holes 64 through the wall of the shaft into the internal passage 18. These apertures are located radially outward 66 of the curved portion of the shaft 12, that is, the side of the shaft 12 that will face the patient's bladder during the surgical procedure described above.

During the foregoing procedure, the shaft passes very close to the patient's bladder, but importantly, the bladder cannot be punctured or damaged in any way during this procedure. The prior art devices often fail to indicate such damage to the bladder that may occur during such procedures, particularly where the disruption caused by such procedures is minimal.

It has been found that with the use of the small holes 64 located along the length of the shaft, once such damage occurs, urine leaks from the bladder and seeps out of the end 17 of the shaft through the holes. The surgeon is thus immediately aware that a bladder failure has occurred. This is considered to be a significant improvement over prior art devices which do not provide any such tamper-evident features.

It should be noted that removal of the shaft from the ventral side of the patient is an important insight of the invention. The instrument has a handle attached to it, which of course must first be removed from the shaft before removal of the shaft from the ventral side can occur. As shown in FIG. 7, however, removal of the handle from the shaft is not necessary. The shaft 70 shown in fig. 7 has a handle end 72 with a series of annular grooves 74 that the surgeon can hold during the procedure described above. The passage through the shaft 70 extends all the way to the handle portion 72, exiting at the trailing end 76 of the shaft. Thus, the linear element 50 and the filiform element 56 are fitted with the shaft 70 and used in the same manner as described above, but the handle removal step is not necessary.

In the embodiment shown in fig. 7, the handle portion 72 has a slightly larger diameter than the shaft portion 78 to provide a slightly better grip on the shaft 70. If it is found that the slightly enlarged diameter of the handle portion 72 causes difficulty in passing the instrument through the patient's body, the diameter of the handle portion 72 may be made exactly the same as the diameter of the shaft portion 78.

It will be appreciated that the gripping arrangement of the handle may be of different forms, one arrangement of particular note being that the handle portion 72 is formed with gripping grooves or ridges arranged in a longitudinal row.

The advantage of the device shown in figure 7 is that the cost of manufacturing the device is far less expensive because it is a one-piece construction. Also, the device does not have to be removed midway through the procedure. However, the torsional force on the device is greatly reduced because the torsional force on the shaft is poor due to the absence of a laterally extending handle at the end.

Of course, the internal passageway need not extend all the way to the forwardmost end of the shaft. As shown in FIG. 8, in some instances it is preferred to close the front end 14 of the shaft to form an end wall 80 and to form a lateral opening 82 through the shaft sidewall immediately adjacent the front end 14. A lateral opening 82 of the type shown in fig. 8 still allows the linear member 50 to be inserted into the shaft interior passage 18, but the end wall provides a steep front face for the instrument, ensuring minimal resistance to the instrument as it passes through the body cavity. It will be clear that the opening 82 can be used to draw a wire through the passage 18 in exactly the same manner as described above. Then, in some procedures, as shown in FIG. 2, it was found that the opening was difficult to pass through body tissue.

As noted above, it is not necessary to connect the handle 20 and the shaft 12 by a threaded connection. Other forms of connection, such as bayonet connections or even some form of interlocking slot connection, are equally satisfactory as long as the engagement and disengagement between the shaft and the handle is easily achieved and can be made relatively straightforward. Another form of mechanical connection is shown in figure 9. The handle 20 is shown as having a reduced diameter stub at its forward end sized to fit within the interior passage 18 of the shaft 12. The shaft 12 is fitted with an aperture 86 through the shaft wall adjacent the rearward end 17. A retractable pin 88 is mounted on the post 84 and is operated by a retraction button 90 located below the shaft of the handle 12. Pressing the retract button 90 will retract the pin 88. Thus, to engage handle 20 with shaft 12, pin 88 is inserted into passage 18 of shaft 12, and if properly inserted, pin 88 will drop into hole 86, thereby locking handle 20 to shaft 12 without rotation. To remove handle 20 from shaft 12, button 90 is depressed to retract pin 88, allowing handle 20 to be removed from shaft end 17. It will be apparent that other forms of mechanically operated interlock configurations on the handle side of the instrument may be employed.

The instrument shown in fig. 10 is similar to that of the previously illustrated embodiment and includes a generally hollow shaft 90 having a cutting tip 92 at one end and a manipulator 94 at the opposite end. The shaft 90 is a generally tubular structure having an internal passage that may extend the entire length of the shaft 90 or may terminate just forward of the end of the shaft 90 as shown by the dashed line 98. A slit 100 extends through the wall 102 of the shaft 90, the slit 100 being longitudinally aligned with the shaft axis, thereby forming a lateral passageway communicating with the internal passageway 96. The slots and channels are best shown in figure 11.

It is considered that the slit 100 is formed radially inward of the bending axis 90.

It is contemplated that in some instances, the wire need not be pulled longitudinally from within the shaft when the shaft is removed from the patient's body cavity. In some cases the wire may be removed laterally from the shaft. In this process, it is avoided that the shaft has to be pulled through the patient's body from the ventral side of the patient. Where the second arm of the U-shaped loop of filamentary material is inserted around the urethra, the filamentary material is then left in the patient, provided it can be removed laterally through the slit 100, and the shaft can then be withdrawn from the vaginal side of the patient. This requires only a single incision on the ventral side. Indeed, it is possible to perform procedures from the vaginal side of the patient, provided that the filamentary material can be drawn laterally out of the internal passage 96 prior to removal of the shaft from the patient.

Fig. 13 depicts another version of the instrument. In this version, the shaft 104 is composed of a solid core material with a relatively shallow groove 106 formed in one side thereof, the groove 106 extending along the entire length of the shaft, or at least along a major length of the shaft. The embodiment shown in fig. 14 is similar to the embodiment shown in fig. 13, but with the grooves 108 being significantly deeper than the grooves 106. It should also be noted that the shaft 110 shown in FIG. 14 is a non-circular cross-sectional structure.

Fig. 15 and 16 depict another version of the cutting tip of the instrument. As shown in fig. 15 and 16, the cutting tip is composed of two side inclined surfaces, reference numerals 112 and 114, the surface 112 being a major surface and the surface 114 being a minor surface. Each of the angled surfaces 112 and 114 is planar and the two surfaces intersect along a line 116 that is perpendicular to the longitudinal axis 118 of the shaft 120, forming the sharpened leading end of the instrument. It is contemplated that the straight line 116 will be offset radially outward from the centerline 118 toward the axis of curvature. This means that in the above described operation, the actual tip of the instrument (i.e. the edge where the two inclined surfaces meet) will be closer to the pubic bone than the bladder as it passes through the body cavity. Moving the sharp cutting edge radially inward of the axis will ensure that the sharp cutting edge does not cut or scrape the pubic bone. When in operation the instrument is passed closely adjacent the bladder, however, the sharp cutting edge will be away from the bladder and the bevel 112 will always push the bladder away from the cutting edge 116.

While the above detailed description has shown, described, and pointed out fundamental novel features of the invention as applied to the above described embodiments, it will be understood that various omissions, substitutions, and changes in the form and details of the device illustrated may be made by those skilled in the art without departing from the spirit of the invention. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. The applicant does not concede that the prior art to which reference is made forms part of the common general knowledge in australia in the art.

Claims (35)

1. A surgical instrument for positioning an elongate member within a patient, said instrument comprising an elongate shaft defining an internal passage, said shaft having a cutting tip formed at one end thereof and an operating means formed at the other end thereof, the shaft including an operating means which is of uniform cross-section along its entire length such that the shaft is insertable through the patient's body, the internal passage being adapted to guide a said elongate member into the patient's body when the instrument is positioned therein.

2. A surgical instrument according to claim 1, wherein the operation device comprises a handle portion which is non-rotatably connected to said other end of the shaft.

3. A surgical instrument according to claim 1 or 2, characterized in that the shaft is arcuately curved.

4. A surgical instrument according to any one of claims 1 to 3, wherein the shaft is tubular.

5. A surgical instrument according to any one of claims 1 to 3, wherein the shaft has a longitudinally extending slit, groove or channel formed therein, the channel extending at least part way along the length and defining at least part of said internal passage.

6. A surgical instrument according to claim 5, characterized in that the shaft is of tubular construction, through the wall of which said longitudinally extending slit is formed.

7. A surgical instrument according to any one of claims 1 to 6, wherein the cutting tip lies in a transverse plane which intersects the axis of the shaft at an angle.

8. A surgical instrument according to any one of claims 1 to 6, wherein the cutting tip lies in two intersecting inclined planes, said inclined planes intersecting along a line which is perpendicular to the longitudinal axis of the shaft.

9. A surgical instrument according to claim 8, wherein a line intersecting the two inclined planes is laterally offset to one side of the longitudinal centerline of the shaft.

10. A surgical instrument according to any one of claims 1 to 9, wherein the shaft has a series of spaced apertures along at least a portion of its length, said apertures extending through the shaft wall into said internal passage.

11. A surgical instrument according to any one of claims 1 to 10, wherein the internal passage terminates behind the cutting tip.

12. A surgical instrument for placing a filamentary element in a female patient to form a loop or loop around the back of the pubic bone and extending around the urethra to the abdominal wall, said instrument comprising:

an arcuately curved tubular shaft defining an internal passage, said shaft having a cutting tip formed on one end thereof and an operating attachment formed on the other end thereof, the shaft being of uniform cross-section along its entire length;

a handle non-rotatably connected to the shaft operating attachment and detachable from the shaft during a surgical procedure;

a flexible thread-like member insertable into and through the internal passage and adapted to pull an end of the filament through the internal passage.

13. A surgical instrument for placing a filamentary element in a female patient to form a loop or loop around the urethra and around the back of the pubic bone to the abdominal wall, said instrument comprising:

an arcuately curved shaft defining a longitudinally extending interior passage, said shaft having a cutting tip formed on one end thereof and an operating attachment formed on the other end thereof;

a handle non-rotatably connected to the shaft operating attachment;

a flexible thread-like member insertable through said internal passage from either end of said shaft, adapted to pull an end of said thread through said internal passage;

the tubular shaft is curved so that the shaft lies in a single plane;

the cutting tip is at least partially in the form of an inclined plane lying in a plane perpendicular to said single plane and intersecting the axis of the shaft at an acute angle.

14. A surgical instrument according to claim 13, characterized in that the acute angle is between 20 ° and 70 °.

15. A surgical instrument according to claim 14, characterized in that the acute angle is 45 °.

16. A surgical instrument according to any one of claims 13 to 15, wherein the cutting tip lies in two intersecting inclined planes which intersect along a line perpendicular to the axis of the shaft.

17. A surgical instrument according to any one of claims 13 to 16, wherein the operating attachment means comprises a screw thread formed on a radially outer surface of the shaft.

18. A surgical instrument according to claim 17, wherein the shaft tapers toward the working attachment to form a smooth transition between the cylindrical central portion of the shaft and said working attachment.

19. A surgical instrument according to any one of claims 13 to 18, wherein the inner surface of said internal passage at or towards the other end of the shaft includes one or more score or detent formations with which said handle engages to provide said non-rotatable connection.

20. A surgical instrument according to any one of claims 13 to 19, wherein said handle includes a hand gripping portion which is substantially larger than said shaft; and an elongated connecting portion adapted to be axially aligned with said other end of the shaft when the handle and the shaft are operatively connected together.

21. A surgical instrument according to claim 20, wherein the elongate connecting portion has a reduced diameter distal end adapted for insertion into the internal passage of the shaft.

22. A surgical instrument according to claim 20 or 21, wherein the handle comprises a ring-like flange on said elongate connecting portion adapted to abut said other end of the shaft, a coupling nut on said elongate connecting portion between the ring-like flange and the handle portion, slidable on said shaft portion, said coupling nut being adapted to engage with a thread formed on the shaft to couple the shaft and the handle together.

23. A surgical instrument according to any one of claims 13 to 22, wherein the shaft has an arcuate portion towards said one end thereof and a linear portion towards said other end thereof.

24. A surgical instrument according to any one of claims 13 to 23, wherein the instrument has at least one aperture extending through the wall thickness between the internal passage and the outer face of the shaft.

25. A surgical instrument according to claim 24 wherein a series of apertures are provided on the radially outer side of said curved shaft spaced along the length of the shaft.

26. A surgical instrument for positioning a filamentary element in a female patient, the filamentary element forming a loop or loop extending around the urethra, around the back of the pubic bone and to the abdominal wall, the instrument comprising a curved tubular shaft defining an internal passage, the shaft having at least one aperture extending through the wall of the tube between the internal passage and the outside of the shaft.

27. A surgical instrument according to claim 26, wherein the aperture is located on the convex side of the shaft.

28. A surgical instrument according to claim 27 wherein the shaft has a cutting tip formed at one end thereof and operative attachment means at the other end thereof, the shaft having an arcuate portion toward said one end thereof and a linear portion toward said other end thereof, the aperture being located in the arcuate portion.

29. A surgical instrument according to any one of claims 26 to 28, wherein there is a series of said apertures spaced along at least part of the length of the shaft.

30. A method of introducing a filamentary element into a female patient, the filamentary element forming a loop or loop extending around the urethra to the abdominal wall, said method comprising the steps of:

a) inserting a curved shaft having a longitudinally extending internal channel into the patient through a first incision in the anterior surface of the vaginal wall, so as to exit the patient through the abdominal wall and through one side of the urethra between the pubic bone and the bladder;

b) threading a wire-like member through the internal passage from one end or the other so that the distal end of the wire-like member passes out of the distal end of the internal passage;

c) attaching a filamentary element to the end of the filamentary element, pulling the filamentary element through the internal passage with the filamentary element;

d) withdrawing the hollow shaft from the patient while the filamentary element remains in place within the patient;

e) inserting the shaft into the patient through the anterior surface of the vaginal wall, such that it passes through the other side of the urethra between the pubic bone and the bladder;

f) pulling the filamentary element through the internal channel to a position using the filamentary element; and

g) the shaft is withdrawn from the patient leaving the filamentary elements in place, thereby forming a loop extending around the urethra to the abdominal wall.

31. A method according to claim 30, wherein the filamentary element is pulled through the patient's body from the ventral side of the patient by the patient's body, the filament being pulled through the patient's body in steps c) and f).

32. A method according to claim 30 or 31, wherein, prior to performing step e), a second incision is made through the anterior surface of the vaginal wall, a passage being created between the first incision and the second incision, the end of the filamentary element adjacent the vagina passing through said passage and exiting said second incision.

33. A method according to any one of claims 30 to 32, characterised in that the shaft withdraws the patient from the ventral side of the patient.

34. A surgical instrument, comprising:

a) a hollow curved tubular shaft defining an internal passage, the shaft having a first sharply cut end surface defining a sharp point; and a non-rotatable handle detachably connected to the other end;

b) a flexible wire-like member at least as long as the shaft, the wire-like member and shaft adapted to draw a wire-like member through the shaft through the internal passage when the handle is removed; and

c) the shaft is shaped and configured for passage through the female patient's body from the anterior wall of the vagina to the anterior wall of the abdomen, through the abdominal wall and into the internal passage, the filamentary element forming a sub-urethral circumferential cable therein extending partially around the back of the pubic bone to the abdominal wall.

35. A surgical instrument substantially as hereinbefore described with reference to the elements of figure 3 of the accompanying drawings.