AU696811B2 - Knot tying method and apparatus - Google Patents

Description

WO 95/19139 PCT/US95100831 KNOT TYING METfOD AND APPARATUS FIELD OF THE INVENTION The present invention relates to the broad field of knot tying, and particularly knot tying in the context of medicine such as the tying of sutures. More specifically, the invention has special applicably to the tying of sutures and other knots in the field of laparoscopic surgery.

BACKGROUND OF THE INVENTION Knot tying and suturing as a method to approximate tissue is a critical element of surgery.

Skill in knot tying is so basic to surgery that medical students learn knot tying early in their studies, and they routinely practice tying various kinds of knots with one hand or both hands.

In laparoscopic procedures, the tying of sutures and other knots is especially difficult and it is not uncommon for the tying of a single knot to require an hour or more. In laparoscopy, there is no tactile sense to the surgeon because of the surgeon's lack of direct contact with the tissue, since the surgeon's sense of feel is reduced by the imposition of the laparoscopic instruments. Further, the surgeon is unable to view directly the site of the surgery, but instead must rely upon a two-dimensional video screen which both magnifies the site and eliminates the opportunity for any depth perception.

Another difficulty is presented by the fact that laparoscopic surgery necessarily is conducted in a confined space, and the instruments are preferably positioned in this confined space in a particular orientation in relation to one another and in relation to the patient. For example, it is desirable that within this confined space, the instruments not be too close SUBST1TUTE SHEET (RULE 26) WO 95119139 PCT/US95/00831 -2together or too far apart, that they be visible through the laparoscope, and that they enter the field of view of the laparoscope tangentially rather than coaxially so that they do not obstruct the view too much. It is also desirable that the instruments advance out of their sheaths toward the video screen and away from the laparoscope in order to avoid the surgeon having to operate under "mirror vision". Finally, procedures employing a single operating port encourage the surgeon to use the dominant hand to manipulate the instrument in the port while using the other hand merely to stabilize the laparoscopic sheath. However, knot tying typically requires both hands, and so an assistant or a device is then necessary to stabilize the sheath while both the surgeon's hands tie the knot.

Suturing and other knot tying are applicable to many different laparoscopic procedures. In laparoscopic cholecystectomy, the cystic duct or artery can be ligated using manual suturing or knot tying techniques rather than an automatic clip. In a laparoscopic appendectomy, the surgeon can use slip knots rather than using a disposable linear stapler. Although laparoscopic staplers have been developed, laparoscopic sutures and other knots will still be needed for many purposes such as closing defects in a staple line, placing purse-string sutures for end-to-end stapling, closing mesenteric defects, and ligating large blood vessels.

Knots used in laparoscopy may be tied either intracorporeally or extracorporeally. Internal knotting requires a high level of expertise by the surgeon, and normally requires at least two operating cannulae and associated graspers. For a square knot, a loop is made in a first end of the material using the first grasper; the second grasper is inserted through the loop and used to grasp the second end; the second end is pulled through SUBSUTUTE SHEET (RULE 26) A~DI~CR~1)LIB~TU II WO 95/19139) PCF/US95/00831 -3the loop to produce a flat knot; another loop is made in the first end of the material using the first grasper; the second grasper is inserted through that loop and used to grasp the second end; and the second end is pulled through that loop to produce an opposing flat knot. The resulting square knot can then be tightened with the two graspers. The first throw may be a simple overhead knot or may be a surgeon's knot. Additional throws may be applied over the second throw to provide additional security. It is important that sequential throws are in opposite directions to avoid producing a "granny" knot.

Many other types of knots are possible depending on the characteristics of the material used, the dexterity of the surgeon, and the circumstances at the suture site. Many knots in laparoscopy are slip knots of some kind to allow the knot to be cinched against the sutured material. These include the Roeder knot, a clinch knot and so-called "hangman's" knots.

Extracorporeally tied knots are obviously much easier to tie than intracorporeally tied knots, but extracorporeally tied knots can be very difficult to place effectively. A number of devices have been developed to assist in placing an extracorporeally tied knot including the "Clarke" ligator, the "Weston" ligator (see "A New Cinch Knot", Obstetrics Gynecology, Vol.

78, No. 1, July 1991, 144-47) and other devices. See, e.g. "An Improved Needleholder for Endoscopic Knot Tying", Fertility and Sterility, Vol. 58, No. 3, Sept.

1992, 640-42; "Roeder Knot for Tight Corners in Conventional Abdominal Surgery", J.R. Coll. Surg. Vol.

36, Dec. 1991, 412; "A Simple Method for Ligating with Straight and Curved Needles in Operative Laparoscopy", Obstetrics and Gynecology, Vol. 79, No. 1, Jn. 1992, 143- 47. Most of the devices for placing an extracorporeally tied knot fall into the category of "knot pushers". A SUBSTITUTE SHEET (RULE 26) I s. a ~~all WO 95/19139 PC/US95/0083 -4knot is formed extracorporeally and is pushed through the cannula by sliding it down the material using a device that engages the knot. The Clarke ligator mentioned above was one of the first knot pushers. It simply consists of a grasping end and an end opposite the grasping end with an open ring. It engages the knot by passing the material through the opening in the ring.

There are also a number of patented knot pushers, including those described in U.S. Patent Nos.

5,234,445 by Walker, 5,234,444 by Christondias, 5,217,471 by Burkhart, 5,192,287 by Fournier, 5,163,946 by Li, 5,129,912 by Noda, 5,133,723 by Li, 5,084,058 by Li, 3,871,379 by Clarke, and 2,012,776 by Roeder. There are also a number of patents directed more toward endoscopic knotters, including U.S. Patent Nos. 5,234,443 by Phan, 5,211,650 by Noda, 4,961,741 by Hayhurst, 4,923,461 by Caspari, 4,890,614 by Caspari, 4,641,652 by Hatterer, and 4,602,635 by Mulhollan. It is believed that an important limitation to these devices is that they do not include a SZQ disposable knot carrier in the manner of the present invention.

SUMMARY OF THE INVENTION The present invention is a system for placing a pretied extracorporeal knot, with particular but not exclusive application to laparoscopy. The knot may be a slip knot or some other knot, especially a knot that can be formed by passing the free end through a knot body which incudes a loop or set of loops.

.:3e 1hA SUBSTITUTE SHEET (RULE 26) ~-ra -348 es~LBBls 5 Accordingly, in an embodiment of the present invention there is provided A knot-tying apparatus, having a plunger assembly; a knot carrier having an at least partially tied knot positioned on the plunger assembly; a tube, the plunger assembly with the knot carrier positioned thereon being slidably positionable within the tube; wherein the plunger assembly and the tube each have a proximal end and a distal end, and the plunger assembly distal end includes a clamp; wherein the plunger assembly includes a tubular element in a plunger shaft inside the tubular element, the o9 20 plunger shaft being attached to and for operating the clamp; 9, 9 wherein the plunger assembly further includes a carrier holder that is positioned at least partially inside the tubular element, the carrier holder and the tubular element each having a distal end and being configured such that the distal end of the carrier holder extends beyond the distal end of the tubular element, and the knot carrier being slidably positioned on the carrier holder distal end 30 that extends beyond the tubular element distal end.

4 9* 9e99 H:\Sjoan\Iraep\8oc1\165 9 95 coral oedical.dco 3/06,98 Y- I -6 Although the system is described principally in the preferred embodiment of laparoscopy applications, it can be appreciated that the system is also suitable for many other intracorporeal and extracorporeal applications.

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*5 S S 50 555w C 55 55 H\Suqan3.Keep\qpecj\l569q 95 coral rnedical.c&,c 3/06I98 WO 95/191,39 PCO1N1951MO3 -7- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a perspective view of an apparatus in accordance with the present invention.

FIG. 2 phows a side sectional view of the knot pusher assembly of the invention.

FIG. 3 shows a detailed-side sectional view of the distal end of the knot pusher assembly.

FIG. 4 shows a bottom view of the distal end of the knot pusher assembly.

FIG. 5 shows an end view of the distal end of the knot pusher assembly prepared for the cutting of suture material.

FIG. 6 shows an end view of the distal end of the knot pusher assembly cutting suture material.

FIG. 7 shows a side sectional view of the proximal end of the plunger assembly of the present invention.

FIG. 8 shows a side sectional view of the distal end of the plunger assembly.

FIG. 9 shows a side sectional view of the distal end of the plunger assembly with the clamp jaws in their relaxed open position.

FIG. 10 shows a side sectional view of the knot carrier of the invention.

FIG. 11 shows a side sectional view of the distal end of the invention showing the knot carrier in the carrying position.

FIG. 12 shows a side sectional view of the distal end of the invention showing the knot carrier in the releasing position.

FIGS. 12A-12F show schematically the process of tying, positioning and trimming a knot in accordance with the process of the present invention.

SUBSTITUTE SHEET (RULE 26) -a lp~ II WO 95/19139 PCITU895/00831 -8- DETAILED DESCRIPTION OF THE INVENTION An overall view of a preferred embodiment of the invention is shown in FIG. 1, including the knot pusher assembly 20 and the plunger assembly 80. As shown in FIG. 1 and also in more detail in the side sectional views of FIG. 2, the knot pusher assembly 20 includes a pusher tube 22 and an inner concentric tube 50. At the proximal end of the knot pusher assembly 20, the pusher tube is attached to a cylindrical handle 24 and the inner concentric tube 50 is attached to a rotator 52 having a longitudinal, radially extending wing 54. The proximal end of the inner concentric tube 50 extends beyond the proximal end of the pusher tube 22 to allow the connection between the inner concentric tube 50 and the rotator 52. The rotator 52 includes a sleeve 56 which extends from the region where the rotator 52 is connected to the inner concentric tube 50, distally over the proximal end of the pusher tube handle 24. An annular space is provided between the rotator sleeve 50 and the inner connector tube 50, which receives a coil spring one end of which is attached to the inner concentric tube or rotator 52, and the other end of which is attached to the pusher tube 22 or pusher tube handle 24. The rotator 52 is capped at the proximal end by a cap 62.

The pusher tube 22 and inner concentric tube are rotatable with respect to one another. This rotation is accomplished by rotating the rotator 52 in relation to the handle 24. The rotation biases and is therefore resisted by the coil spring The distal end of the knot pusher assembly includes the distal ends of the pusher tube 22 and inner connector tube 50, which are better shown in the detail view of FIG. 3-6. FIG. 3 and FIG.. 4 are detailed views showing the distal end of the pusher tube 22 and inner concentric tube 50. As can be seen, the distal end of SUBSTITUTE SHEET (RULE 26) WO 95/19139 'cr/luSIgsI/IOol83 -9the inner concentric tube 50 is slightly recessed from the distal end of the pusher tube 22. Moreover, the ends are specially shaped. The end of the pusher tube 20 has a bevel 30 on one side and has a indentation 32 on the opposite side. At the proximal extreme of the indentation 32 is a pusher tube slot 34 extending longitudinally toward the proximal end of the knot pusher assembly 20. The end of the inner concentric tube includes a bevelled side 66 and a flat portion 68.

Intermediate in the flat portion 68 is an inner concentric tube slot 70 which extends longitudinally toward the proximal end of the knot pusher assembly The inner concentric tube slot 70 aligns with the pusher tube slot 34 when the inner concentric tube is in its unrotated position in relation to the pusher tube 22, or in other words, when the spring 60 in the proximal end of the knot pusher assembly 20 (see FIG. 2) is unbiased. As shown in the end view of FIG. 6, when the inner concentric tube 50 is rotated in relation to the pusher tube 22 to bias the spring 60, the inner concentric tube slot 70 becomes unaligned with the pusher tube slot 34. In the aligned position of FIG. 5, the aligned slots 34 and 70 can receive a length of material 72. By rotating the inner concentric tube 50 in relation to the pusher tube 22, they become unaligned to thereby cut the material 72 as shown in FIG. 6.

The plunger assembly 80 is shown in detail in FIGs. 7-8. The plunger assembly 80 includes a plunger shaft 82 which is a elongated tubular element. The proximal end of the plunger shaft 82 is attached to a plunger handle 84. Inside and concentric with the tubular plunger shaft 82 is a carrier releaser 86 which is also a tubular element. The distal end of the carrier releaser 86 coincides with the distal end of the plunger shaft 82. The proximal end of the carrier releaser 86 SUBSTITUTE SHEET (RULE 26) 4L L ~U Y I WO 95/19139 PC/US9500831 extends past the proximal end of the plunger shaft 82 and into the interior cavity of plunger handle 84 where it engages the mechanism of a carrier release button 88.

The mechanism is any suitable arrangement which drives the carrier releaser 86 distally upon actuation of the carrier release button 88. In the embodiment shown, the proximal end of the carrier releaser 86 is attached to a ramp 90 which engages a sloped surface on the carrier release button 88. Thus by pushing the carrier release button 88 into the plunger handle 84, the sloped surface of the carrier release button 88 engages the ramp 90 at the proximal end of the carrier releaser 86 to drive the carrier releaser distally relative to the plunger shaft 82 and plunger handle 84. This distal displacement has the effect of protruding the distal end of the carrier releaser 86 past the distal end of the plunger shaft 82.

The carrier releaser 86 may be biased toward the proximal end by a suitable spring (not shown) so that it returns proximally each time the carrier release button 88 is released.

Inside and concentric with the carrier release is a carrier holder 140 which is fixed in relation to the plunger shaft 82. Inside and concentric with the carrier holder 140 is a clamp holder 96 which extends from the distal end to the proximal end where it is attached to a clamp actuator 98. The clamp actuator 98 is a cylindrical element received by the plunger assembly handle 84. The clamp actuator 98 has a central cavity to contain the inner potion of the carrier release button 88 and the ramp 90 at the proximal end of the carrier releaser 86. The distal end of the clamp actuator 98 abuts against the end of a coil spring 102 contained within the plunger assembly handle 84 so that the clamp actuator 98 and attached clamp holder 96 are biased proximally.

SUBSTrUTE SHEET (RULE 26) WO 95/19139 PCr1US95/0083 I -11- The distal end of the clamp holder 96 is attached to a spring clamp 110, better shown in FIGs. 8- 9, in which the carrier is omitted for clarity. FIG. 8 shows the spring clamp 110 in the closed position, wherein the clamp holder 96 is positioned distally by the relaxed clamp actuator 98 so that the clamp holder 96 is retracted partially into the plunger assembly 80. The proximal retraction of the clamp holder 96 urges the sloped backs 116 of the clamp jaws 118 against the distal end of the carrier holder 86. The distal end of the carrier holder 140 thereby exert an axial force on the backs 116 of the clamp jaws 118, to urge the clamp jaws 118 shut. In FIG. 9, the clamp actuator 98 (see FIG. 7) has been depressed, to displace the clamp holder 96 and attached clamp jaws 118 distally. This causes the backs 116 of the clamp jaws 118 to protrude past the distal end of the carrier holder 140, thereby allowing the clamp jaws 118 to assume their normally open position.

The carrier 220 is shown in detail in FIG. The carrier 120 includes a spool 122 and a sheath 124 over the spool 122. The spool is a tubular element being flared at the distal end 125 with a plurality of longitudinally extending slots 126. The slots 126 allow for space for the flared distal end to deform radially inward to reduce the effective diameter and circumference of the distal end 125. At the proximal end of the spool 122 is a set of threads 130 on the radially outer surface. Between the distal end 125 and proximal end is a radially extending ring 132. A length of material and a knot, together 142, is rolled onto the spool 122 in the region between the extreme digital end 125 and the ring 132.

The sheath 124 is also a tubular element, concentric with the spool 122. At the distal end of the sheath, the radially inner surface is chamfered in the SUBSTITUTE SHEET (RULE 26) I WO 95/19139 PCTUS95/00831 -12region overlying the flared distal end 125 of the sroul.

At the proximal end, the radially inner surface includes a set of threads 136 that mate with the threads 130 in the radially outer surface of the spool 122. The spool 122 and the sheath 124 are held together by the engagement of these respective threads 130 and 136.

A detail of the carrier 120 positioned on the plunger assembly 80 is shown in FIG. II. As can be seen, the carrier 120 slides over the distal end of the carrier holder 140. The extreme distal end of the carrier holder 140 is dimensioned such that it exerts a radially outward force on the flared distal end 125 of the spool 122 of the carrier holder 120. This radially outward force deforms the flared distal end 125 of the spool 122 radially outward to bind the material and knot 142 that is rolled onto the spool 122, between the spool 122 and the sheath 124.

FIG. 12 shows the carrier 120 being released from the carrier holder 140. As explained above, the carrier 120 can be pushed partly off the carrier holder 84 by actuating the carrier release button 88 (see FIG.

7) to protrude the carrier releaser 86 distal end past the plunger shaft 82 distal end. This causes the flared distal end 125 of the carrier 120 to extend past the distal end of the carrier holder 140, thereby allowing the flared distal end 125 of the carrier 126 to relax and contract radially. This relieves the binding force between the spool 122 and the sheath 124 so that the material 142 can come out of the carrier 120.

The operation of the device is shown in FIGs.

12A-12F. As shown in FIG. 12A, the knot pusher assembly is inserted into a cannula 21 prior to the plunger assembly 80 being inserted into the knot pusher. This ensures the safety and security of the needle and suture.

during their insertion. The carrier 120 is then placed SUBSTITUTE SHEET (RULE 26) I WO 95/19139 PCT/US95/O0831 -13over the clamp 110 and onto the carrier 140. A needle 150 is previously attached to the suture material 142.

The carrier 120 is then secured in the clamp 110, and the plunger assembly 80 is inserted into the knot pusher assembly As shown in FIG. 12B, the needle 150 is taken from the clamp 110 by another instrument 160 (such as a needle holder or clamp) passing through another cannula.

The needle 150 is passed through or around a feature, such as through tissue or around a vessel 170, and handed back to the clamp 110. As shown by FIG. 12C, the knot and material 142 is released from the carrier 120 by actuating the carrier release 86 to protrude the carrier 120 past the distal end of the carrier holder 140 so that the flared distal end 125 of the carrier spool 122 relaxes radially inward to relieve the binding on the knot and material 142 (see FIG. 12). This releasing of the knot and material provides the necessary slack in the material to accomplish the suturing or tying. The releasing of the knot allows the knot to lightly cinch down on the lead end of the material which is now grasped by the clamp 110.

As shown in FIG. 12D, pulling on the plunger assembly within the knot pusher assembly 20 while pushing on the knot pusher assembly 20 retracts and tensions the leads of the material 140 which allows the knot pusher assembly 20 to engage the leads. Specifically, the leads pass into the aligned pusher tube slot 34 and inner concentric tube slot 70 (see FIG. Continued pulling on the plunger assembly 80 while pushing on the knot pusher assembly 20 tightens and drives the knot 142 into position against the vessel 170 to tightly tie the vessel 170.

The leads of material 140 may then be cut, either immediately adjacent to the knot or away from the SUBS1TFU'E SHEET (RULE 26) WO 95/19139 PCI'US95/00831 -14knot to leave longer loose ends as desired. The cutting is accomplished by positioning the knot pusher assembly at the cutting site, still with the material in the aligned pusher tube slot 34 and inner concentric tube slot 70 (see FIG. 4 again). The inner concentric tube is then rotated in relation to the pusher tube 22 (see FIG. 6) by rotating the rotator 52 while grasping the handle 24 (see FIG. 2) to unalign the pusher tube slot 34 and the inner concentric tube slot 70. This leaves a tied knot on a vessel 170 as shown in FIG. 12F.

The plunger assembly 80 is then withdrawn from the knot pusher assembly 20, and the carrier 120 and material leads including the needle are discarded. The instrument is then ready to be reloaded with a new carrier 120 and needle for tying the next knot or suture.

SUBSTITUTE SHEET (RULE 26) I I I--

Claims (7)

1. A knot-tying apparatus, having a plunger assembly; a knot carrier having an at least partially tied knot positioned on the plunger assembly; a tube, the plunger assembly with the knot carrier positioned thereon being slidably positionable within the tube; wherein the plunger assembly and the tube each have a proximal end and a distal end, and the plunger assembly distal end includes a clamp; wherein the plunger assembly includes a tubular element in a plunger shaft inside the tubular element, the plunger shaft being attached to and for operating the 20 clamp; wherein the plunger assembly further includes a carrier holder that is positioned at least partially inside the tubular element, the carrier holder and the tubular element each having a distal end and being configured such that the distal end of the carrier holder extends beyond the distal end of the tubular element, and the knot carrier being slidably positioned on the carrier holder distal end that extends beyond the tubular element distal end.

2. The knot-tying apparatus of claim 1, wherein the clamp includes a pair of opposing clamp jaws that are biased apart, each jaw being attached to the plunger shaft and each jaw having a shaped surface engaged by the carrier holder distal end to close the jaws when the plunger shaft is in a first position in relation to the carrier holder and to allow the jaws to open when the plunger shaft is in Ht\Susan\Keep\pec\lS6? 95 coral medical.doc 3106198 i 16 a second position in relation to the carrier holder which is distal from the first position.

3. The knot-tying apparatus of claim 1 or claim 2, wherein the plunger assembly further includes a carrier releaser that is at least partially inside the tubular element and slidably engaged with respect thereto, the carrier releaser having a distal end engageable with the knot carrier and operable from the plunger assembly proximal end, whereby the operation of the carrier releaser distal end slides the carrier releaser distal end to push the knot carrier in the distal direction of the carrier holder.

4. The knot-tying apparatus of any one of claims 1 to 3, wherein the knot carrier includes a spool end, a sheath over the spool to define an angular space there between to receive the knot. 20

5. The knot-tying apparatus of claim 4, wherein the spool includes a central hole to receive the carrier S* holder. **0

6. The knot-tying apparatus of any one of claims 1 to 5, wherein the carrier holder has a distal end and the carrier central hole is flared radially inward at the distal end, so that the spool is urged radially outward by the carrier holder when the carrier distal end is 30positioned on the carrier holder, whereby the knot is held 30 between the spool and sheath and the spool relaxes radially inward when the carrier distal end is not positioned on the carrier holder, whereby the knot is no longer held between the spool and the sheath. good 6 9 9 95 coral medical.d=c 3/06/98 17

7. A knot-tying apparatus, substantially as herein described with reference to the accompanying drawings. Dated this 3rd day of June 1998 CORAL MEDICAL By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent Attorneys of Australia H.,\Susan\Xeep\9peci\15 6 9 9 95 coral medical.doo 3/06198 M