Surgical knot pusher and method of use

[0001] This application is a continuation of U.S. patent application Ser. No. 10/011,452 filed on Oct. 30, 2001 now U.S. Pat. No. 6,884,249 which is based on U.S. provisional application 60/269,314, filed on Feb. 16, 2001.

[0002] The invention relates generally to surgical tools for preparing sutures, and to methods pertaining thereto. More particularly, this invention relates to a slip knot pusher for advancing a prepared slip knot down a length of suture without deforming or collapsing the knot.

[0003] Many surgical procedures require a knot to be tied. For example, to reattach torn tissue, a surgeon will typically form a slip knot around the detached tissue to hold the tissue in place, rather than stitch the torn tissue to the surrounding area. Formation of the slip knot requires the surgeon to manually tie a knot on the ligatures, which are long, relatively straight strands of suture material, after the ligature is threaded through the tissues to be sutured together. This procedure is often tedious and time-consuming. There is also a tendency for the slip knot to deform or collapse as the surgeon manually forces the knot down into its proper position. In addition, tying the knot in this manner is often difficult during endoscopic surgeries such as arthroscopies, where the visual field for the surgeon is severely limited by the narrow surgical area. Because of these setbacks, there exists a need for an improved method of tying a slip knot, and for surgical tools that will facilitate such a goal.

[0004] The present invention overcomes the drawbacks inherent in prior art surgical methods and devices by providing a surgical knot pusher device that allows a prepared slip knot to be pushed down a length of suture without deforming or collapsing the knot. In one embodiment, the pusher includes a handle portion and an elongate body extending from the handle portion. The elongate body has a distal tip at a distal end of the elongate body. A groove is formed in a portion of the distal tip. The tip also includes a central channel extending from the groove to a distal end of the distal tip. The distal tip may be tapered and bent with respect to the elongate body. The distal tip can be bent in a range of angles with respect to the elongate body. Alternatively, the distal tip of the surgical knot pusher device can be straight.

[0005] In one embodiment, the pusher is formed from a rigid plastic or metal. However, in another embodiment, the pusher can be formed from a malleable material that enables the surgeon to adjust the angle of the distal tip during surgery.

[0006] The surgical knot pusher device of the present invention can be used with a suture locking device for repairing soft tissue defects. The suture locking device can include a wall anchor attached to a tissue implant by a connecting suture having a preformed slip knot. In an exemplary method, the wall anchor is threaded through a soft tissue defect and placed against the outer wall of the tissue surface, with the connecting suture attached to the wall anchor extending across the defect or tear. The tissue implant can be positioned on an opposite wall of the tissue surface. The surgical knot pusher device of the present invention can then be deployed to force the preformed slip knot down the leg of the suture extending from the tissue implant and into the implant itself. The wall anchor acts as a pulley as tension is applied to the connecting suture, effecting closure of the tear and allowing the tissue implant to be pushed into the opposite wall of the tissue surface. An inserter tool comprising a cannulated needle and a push rod can be utilized to introduce the wall anchor and attached suture through the tissue defect.

[0007] Further features of the invention, its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the drawings and the preferred embodiments.

[0019] Referring now to the drawings and particularly to FIG. 1, a surgical knot pusher device 10 of the present invention is shown. The device 10 includes a handle portion 12 that can comprise a loop 14 for engaging a user's finger. Though handle portion 12 is illustrated with one loop 14, the handle portion 12 may include more than one loop 14 for engaging a plurality of the user's fingers. Alternatively, the handle portion 12 can comprise a gripping surface instead of loop 14. It is contemplated that the handle portion 12 can take any form commonly employed in the surgical tool art such as, e.g., a knob or grip.

[0020] As illustrated in FIGS. 1 and 2, extending from the handle portion 12 is an elongate body 16 having a distal tip 18 at a distal end 20 of the elongate body 16. Distal tip 18 may be curved, or bent, and tapered. For example, the distal tip 18 may extend from the elongate body 16 at an angle in the range of approximately 0° to 35°. In a preferred embodiment shown in detail in FIGS. 3 and 3A, distal tip 18 extends at an angle in the range of approximately 12° to 18° from the elongate body 16. In another embodiment, distal tip 18 can extend at an angle in the range of approximately 27° to 33° with respect to elongate body 16. The bent and tapered distal tip 18 enables a surgeon to maneuver around the curvature of the patient's anatomy. For example, the bent and tapered distal tip 18 can effectively move around the curves of a bone joint, such as the condyles of the knee joint.

[0021] In one embodiment, distal tip 18 begins to bend from the elongate body 16 at about 3.00 inches from the distal end 20 of distal tip 18. Along a portion of the distal tip 18 is a dimple, or groove 22 located approximately 0.25 inches from the distal end 20 of the elongate body 16. FIGS. 3 and 3A show in detail the groove 22 having a contoured surface 24, the groove 22 being angled with respect to the surface of tip 18. Groove 22 is situated on the surface of distal tip 18 facing the bend and enables a length of suture extending out of the groove 22 to lie against the elongate body 16 without substantially increasing the overall diameter of the surgical knot pusher device 10.

[0022] Distal tip 18 also includes a central channel 26 that runs from the groove 22 to the distal end 20 of the distal tip 18. Central channel 26 has a proximal end that is formed by a radiused wall, and channel 26 has a diameter in the range of approximately 0.025 inches, which provides sufficient clearance for a strand of suture to pass therethrough. As shown in FIGS. 4 and 4A, approximately 0.10 inches from the distal end 20, the tip 18 tapers from a 0.08 inch outer diameter to a 0.06 inch outer diameter. At this same position, central channel 26 within distal tip 18 begins to flare out to a conical opening 28 having an angle in the range of approximately 41° and a depth in the range of approximately 0.047 inches. The conical opening 28 should be of sufficient shape and dimensions to cover at least 50% of the knot intended to be pushed forward. The distal end 20 of distal tip 18 is blunt so as not to damage tissue when inserted into a patient's body.

[0023] Though illustrated with a bent distal tip 18, surgical knot pusher device 10 can also include a straight distal tip 18 that has no bend. Typically, the overall length of the surgical knot pusher device 10, including the handle 12, is in the range of about 7.5 inches, while the elongate body 16 and distal tip 18 together are in the range of about 5.78 inches long. Elongate body 16 can have a diameter in the range of about 0.093 inches. It is understood that all dimensions are merely exemplary and can be modified and altered as deemed appropriate.

[0024] Surgical knot pusher device 10 can be formed from a rigid material and can be made of either biocompatible metal or plastic. For example, device 10 may be formed of surgical grade stainless steel, titanium, or titanium alloys. However, it is contemplated that pusher 10 can be formed from a malleable metal or plastic to enable the surgeon to manually adjust the angle of the distal tip 18 as deemed appropriate. Examples of such materials include stainless steel.

[0025] Surgical knot pusher device 10 of the present invention can be used with conventional suture locking systems 80 such as shown in FIG. 5 where an outer wall anchor 40 and a tissue implant 50 are positioned on the outer wall 74 and inner wall 72, respectively, of a tissue surface 70 having a tear 76 or defect. A connecting suture 60 attached to the outer wall anchor 40 and tissue implant 50 is extended across the tear 76, the anchor 40 acting as a pulley to effect closure of the soft tissue defect 76 when force is applied to the suture 60. The suture 60 connecting outer wall anchor 40 to tissue implant 50 can be tied with a slip knot for ease in locking the suture 60.

[0026] FIGS. 6A and 6B illustrate in detail an example of a suture locking system 80 suitable for use with the device 10 of the present invention. Suture locking system 80 includes an outer wall anchor 90 and an inner wall implant 100. Outer wall anchor 90 comprises a generally cylindrical base 92 having a semi-circular flange 94 extending therefrom. A hole 96 is provided on flange 94 for attaching a suture. Outer wall anchor can have a total width in the range of about 5.0 mm and a total height in the range of about 2.5 mm. Inner wall implant 100 is shaped like a tophat and comprises a generally cylindrical base 102 having thereon a generally oval top surface 104. A through-hole 106 extends through the top surface 104 and out the cylindrical base 102 for threading a suture therethrough. Implant 100 has a total height in the range of about 1.0 mm and a width in the range of about 3.0 to 4.5 mm. Through-hole 106 is dimensioned so as to be able to firmly engage a surgical knot.

[0027] Suture locking system 80 can be deployed using inserter tool 120 illustrated in FIG. 7. Inserter tool includes a cannulated needle 122 having a push rod 124 extending therethrough. As shown, a connecting suture 110 connects anchor 90 to implant 100. The connecting suture 110 can extend into a slip knot as it exits from the through-hole 102 of the implant 100. A slot 126 on the cannulated needle 122 enables the anchor 90 to be seated within the cannulated needle 122 while the connecting suture 110 extends out of the cannulated needle 122. Implant 100, which is connected to connecting suture 110, can reside outside of the cannulated needle 122 entirely.

[0028] FIGS. 8A-8M illustrate generally a method for surgically repairing a standard repairable meniscus tear 206 using the surgical knot pusher device 10 of the present invention in combination with the suture locking system 80 described above. First, the meniscus tear 206 is evaluated and prepared in the usual manner. Then, the suture locking system 80 is preloaded onto an inserter tool 120. To effect repair of the meniscus tear 206, cannulated needle 122 of inserter tool 120 containing the outer wall anchor 90 attached by connecting suture 110 to tissue implant 100 is inserted through a standard medial or lateral portal. The needle 122 is passed through the tissue body, or meniscus 200, and into the pericapsular tissue posteriorly. Care should be taken to aim the needle away from the popliteal fossa and avoid any neurovascular injury during the procedure.

[0029] Connecting suture 110 can be tied in a slip knot to attach tissue implant 100 to the outer wall anchor 90. As shown in FIG. 8C, cannulated needle 122 is extended through the meniscus tear 206 to the outside wall 204 of the meniscus 200, whereupon the push rod 124 of inserter tool 120 is actuated and outer wall anchor 90 ejected from the cannulated needle 122 through to the outer wall 204 of the meniscus 200. Inserter tool 120 is then removed, leaving the anchor 90 against outer wall 204 with suture 110 extending through the meniscus tear 206 as illustrated in FIG. 8F. The limb of the connecting suture 110 can be pulled to assure capture and fixation of the outer wall anchor 90.

[0030] The free end of connecting suture 110 can then be threaded through conical opening 28 and the central channel 26 of the surgical knot pusher device 10, exiting out from the channel 26 to groove 22 as shown in FIG. 8G. Contoured groove 22 enables the surgeon to rest the leg of the connecting suture 60 against the groove 22 and along the length of the elongate body 16 without significantly affecting the overall diameter of the device 10 or encumbering the workspace of the surgeon. In FIG. 8H, distal tip 18 of device 10 is placed against the slip knot 112 such that about 50% of the knot 62 is surrounded by conical opening 28. Using gentle pressure while holding the leg of suture 110 taut against the device 10, the surgeon can initiate a pulling/pushing action to slide the surgical knot pusher device 10 towards the tissue implant 100, until the slip knot 112 moves down the suture strand 110 and against the tissue implant 100, as in FIG. 8I. Slightly more pressure should be applied to pull the connecting suture 110 than is applied to the pusher device 10. This will prevent the accumulation of slack in the connecting suture 110, allowing the tissue implant 100 and slip knot 112 to slide smoothly.

[0031] The limb of the connecting suture 110 should continue to be pulled to advance the slip knot 112 and the tissue implant 100 down to the inner wall 202 of the meniscus 200. The tissue implant 100 should be seated snugly, i.e., “dimpled” into the inner wall 202 of the meniscus 200, and the slip knot 112 abutting the top surface 104 of the implant 100, as shown in FIG. 8K. Tension should continue to be applied to the connecting suture 110 with the pusher device 10 until the slip knot 112 is tightened. The slip knot 112 can then be lodged in the through-hole 106 of the tissue implant 100 by applying pressure against the slip knot 112 with the pusher device 10. With tension on the connecting suture 110, the outer wall anchor 90 provides support against the outer wall 204. As the connecting suture 110 tightens, anchor 90 acts as a pulley, enabling the connecting suture 110 to pull the tissue surrounding the meniscus tear 206 together to promote healing of the meniscus 200.

[0032] Typically the knot-engaging tissue implant 100 is formed from a pliable and resilient material having a configuration that enables knot 112 to become lodged therein. By exerting force on the distal tip 18 of device 10, the surgeon can force the tissue implant 90 into the inner wall 202 of the meniscus 200. As seen in FIGS. 8K and 8L, once the tissue implant 90 is pushed firmly against the inner wall 202 of the meniscus 200, and the slip knot 112 tightened, the device 10 can be retracted. The connecting suture 110 is then cut with an arthroscopic cutter (not shown) to leave approximately about 2 mm of suture length. As shown in FIG. 8M, the above procedure can be repeated until the desired amount of sutures is placed across the meniscus tear 206. Finally, when the procedures are complete, the meniscus 200 is probed to assure a stable repair.

[0033] While the present invention is described for use with a slip knot, it is contemplated that the pusher 10 can be utilized with any type of surgical knot. Further, the pusher 10 can be effective in surgical procedures other than tissue repairs, the pusher 10 being effective for knot pushing in any surgical procedure requiring suturing.

[0034] It will be understood that the foregoing is only illustrative of the principles of the invention, and that various modifications can be made by those skilled in the art without departing from the scope and spirit of the invention. All references cited herein are expressly incorporated by reference in their entirety.