Method of using an endoknot pusher surgical instrument

A surgical instrument for positioning and tying knots during endoscopic surgery is provided with an elongate shaft having a ligature restraining aperture for accepting a strand of the ligature.

FIELD OF THE INVENTION 
The present invention is a knot pushing surgical instrument for endoscopic 
procedures. The instrument is used to position and tighten knots formed in 
ligatures during endoscopic surgery. 
BACKGROUND OF THE INVENTION 
Knot pushing and positioning instruments are known in the art. U.S. Pat. 
No. 2,595,086 to LARZELERE, discloses a ring-shaped structure having an 
open slot. In use, a ligature is placed around an anatomical structure and 
both strands of the ligature are positioned on the periphery of a slotted 
ring structure. The knot itself is positioned in a slot formed in the ring 
and the slack strands are taken up together as the knot is pushed onto an 
anatomical structure. The ring structure is attached to a rod which is 
used to manipulate the tool and to push the knot into position. 
FIG. 10 shows the working end of another prior art knotpushing device 
referred to as the Clarke-Reich ligator, which is distributed by Marlow 
Surgical Technologies, and which is intended for endoscopic use. This 
structure shows an aperture which communicates to the outside of the 
instrument through a slot. In use, one strand of the ligature is placed in 
the aperture by passing it through the slot. The tool is pushed causing 
the knot to slip over itself as it moves into position. 
Open structures as taught by this prior art are difficult to use, since the 
instrument may slip off the ligature. Such structures can also have a 
tendency to become tangled with the knot and are not useful for untangling 
a knot. The seat of the Clarke-Riech ligator is particularly problematical 
when it engage an open loop of a loosely tied knot. The geometry of this 
device prevents knots from being effectively tightened. Also, the 
conventional use of the Clarke-Reich ligator on secondary knots frays the 
ligature which weakens it. Most surgeons do not prefer tools which form 
loose knots in frayed ligature. These problems have collectively spawned 
the development of the endoscopic surgical stapler. 
SUMMARY OF THE INVENTION 
In contrast to these prior art structures, the present knot pusher 
invention permits the surgeon to tie a multiple throw surgeon's knot, 
tighten it properly and secure this primary knot with a series of well 
formed secondary hitches. The structure of the present invention includes 
a closed aperture located at the working end of an elongated rod. A relief 
is formed at the location of the aperture to provide a volume or clearance 
space to locate and protect the knot as it is pushed through the 
percutaneous port into the surgical field. A T-shaped handle is provided 
to facilitate use.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 shows a perspective view of the endoknot pusher. The endoknot 
surgical instrument 10 has a substantially T-shaped handle 11, which is 
preferably manufactured from medical grade polysulfone plastic. This 
handle 11 structure is molded onto an elongated stainless steel shaft or 
rod 12, which is preferably 6.5 millimeters in diameter, and approximately 
30 centimeters in length. The working end 13 of the instrument includes a 
ligature restraining aperture 14 formed proximate the tip 15 of the 
instrument. A scalloped relief 16 is formed adjacent or proximate the 
ligature restraining aperture 14 to provide and define a knot reception 
volume 26. 
The ligature restraining aperture 14 is completely deburred and chamfered 
or rounded to prevent snagging of the ligature passed through the 
restraining aperture 14. The ligature restraining aperture 14 has a 
completely closed periphery with a preferred diameter of 0.125 inches. The 
tip 15 of the instrument is partially hemispheric, with a preferred radius 
of approximately 0.125 inches, and is therefore blunt. This ligature 
restraining aperture 14 must be threaded with the ligature in operation. 
FIG. 2 is a highly schematic view, depicting the surgical field where the 
endoknot surgical instrument 10 is used. The patient's abdominal wall 17 
has been punctured with a trocar, and an endoscopic access port 18 has 
been placed in the wall, providing communication to the abdominal cavity 
19. The cavity 19 contains an internal anatomical or prosthetic structure 
20 such as a pedicle, vascular structure or suture ring for ligation. The 
surgeon utilizes tools to place the ligature 21 around the internal 
anatomical structure 20, passing the free standing strand 22 captive and 
the tying strand 23 out of the same percutaneous port 18. 
FIG. 3 should be considered together with FIG. 4 and FIG. 5. Together, the 
figures show a procedure for tying a primary surgeon's knot 24. In FIG. 3 
the surgeon has formed a classic double throw surgeon's knot 24 in the 
captive tying strand 23, by winding it around the free standing strand 22. 
This knot 24 is formed extracorporally. After knot 24 formation, the 
surgeon threads the captive tying strand 23 into the restraining aperture 
14 of the endoknot pusher surgical instrument 10. It is highly preferred 
to tag the terminal end of the captive tying strand 23 with a forceps as 
indicated by forceps 30. In use the surgeon may hold the endoknot pusher 
instrument 10 in his hand, and the forceps 30 on the strand 23 apply 
slight traction to the standing strand 22 to transfer the knot 24 to the 
tying strand 23 as shown in FIG. 4, and to prevent the knot from becoming 
tangled. 
In FIG. 4 the bubble 28 indicates that the surgeon presses the tying strand 
23 against the rod 12, as the rod 12 and tying strand 23 are is advanced 
toward the anatomical internal structure 20. During this process the knot 
24 lies adjacent the relief 16, trailing behind the restraining aperture 
14. In practice, the knot 24 is quite small and lies in contact with the 
relief 16, within the knot reception volume 26. 
FIG. 5 depicts the advancement of the rod through the port (not shown). In 
the figure, the knot 24 has been positioned on the anatomical structure 20 
and the tip 15 is pushed pass the structure 20 to tighten the knot 24. 
During this process the standing stand 22 is withdrawn away from the 
anatomical structure 20 as indicated by arrow 29 to take up the slack. 
With this knot 24 tightened, the strands 22 and 23 are no longer capable 
of relative motion past the anatomical internal structure 20. This 
prevents the passage of another surgeon's knot onto the ligature 21. 
However additional security hitches or other secondary knots may be placed 
to secure the surgeon's knot 24 as shown in connection with FIG. 6, FIG. 
7, and FIG. 8. 
In FIG. 6 the captive tying strand is tagged with a forceps. Slight 
traction is applied to the tying strand 23 to permit formation of a simple 
hitch 32 in the standing strand 22. In practice, this hitch is easily 
formed while the surgeon grasps the endoknot pusher surgical instrument 10 
in one hand. This practice speeds hitch formation by the surgeon. Next, 
the surgeon moves the free standing strand 22 and the captive tying strand 
23 together and holds them both in one hand with a slight amount of slack 
in the captive tying strand 23 as shown in FIG. 7. This grasping action is 
depicted in the figure. Next, the surgeon inserts the endoknot pusher 
surgical instrument 10 through the port 18 and pushes the handle. This is 
depicted in FIG. 8. Since the strands 22 and 23 are immobile with respect 
to each other at the primary knot 24 and at the surgeon's hand, the hitch 
32 slides over itself as it is passed through the port and into contact 
with the primary knot 24. During passage of the hitch through the port 18, 
the hitch lies in contact with the relief 16 as the ligature 21 slides 
through the knot restraining aperture 14. Advancement of the endoknot 
pusher past the primary knot 24. As shown in FIG. 7, tightens the hitch 32 
onto the primary knot 24. 
Although the preferred primary knot 24 is the surgeon's knot which is the 
preferred primary knot for most surgical procedures, other knots may be 
used with great facility. In a similar fashion, the preferred secondary 
knot 32 is shown as a simple hitch 32 but other knots may be used as well. 
The fact that the ligature 21 strand is captive or trapped in the ligature 
restraining aperture 14 of the instrument, permits the surgeon to 
positively control the tying strand 23 with one hand throughout the tying 
procedure. If the surgeon "lets go" of the instrument intentionally or 
accidentally, the captive strand will not disengage or come off the 
instrument 10. Thus the captive strand provides instant orientation to the 
surgeon as to which strand is which during the knot tying operation. This 
helps the surgeon to develop a variety of methods to un-tangle knots or to 
place additional knots or hitches on the ligature without twisting. 
The T-shaped handle 11 is small and has a bilateral symmetry around the 
plane shown in FIG. 1 by reference line 25. This handle permits use of the 
tool by both right and left-handed surgeons with equal facility. The 
handle is asymmetrical in the plane defined by section lines 36 which be 
provides an indication of the angular orientation of the relief 16 and the 
ligature restraining aperture 14. This provides a visual and tactile 
reference to the physician outside of the surgical field. Although other 
handle shapes are contemplated within the scope and spirit of the 
invention they should be ambidextrous with an indexing structure to permit 
instinctive orientation of the relief within the surgical field. Also 
although variations on the aperture and relief are possible it is 
important to ensure that the relationship between the handle and relief be 
preserved.