LOOP/ BUTTON SYSTEM FOR TENDON AND LIGAMENT RECONSTRUCTION

Abstract

The invention relates to a medical implant (1), comprising at least a first cortical fixation device (200) for fixing a ligament or tendon graft (G) in a desired position, wherein said first cortical fixation device (200) comprises a body (201) having a front side (201a) and a rear side (201b), which rear side (201b) faces away from the front side (201a), and wherein said body (201) comprises a first and an adjacent second through-hole (210, 211), which through-holes (210, 211) extend from the front side (201a) to the rear side (201b) of said body. According to the invention the medical implant (1) further comprises a first suture thread (100) extending through the through-holes (210, 211) and forming a twisted loop (104) and a non-twisted loop (105) on the front side (201a) of the body (201), and a sliding knot (108) on the rear side (201b) of the body (201), and wherein the medical implant (1) comprises a second suture thread (300) extending through the sliding knot (108).

Claims

1. A medical implant (1), comprising at least a first cortical fixation device (200) for fixing a ligament or tendon graft (G) in a desired position, wherein said first cortical fixation device (200) comprises a body (201) having a front side (201a) and a rear side (201b), which rear side (201b) faces away from the front side (201a), and wherein said body (201) comprises a first and an adjacent second through-hole (210, 211), which through-holes (210, 211) extend from the front side (201a) to the rear side (201b) of said body, characterized in that the medical implant (1) further comprises a first suture thread (100) extending through the through-holes (210, 211) and forming a twisted loop (104) and a non-twisted loop (105) on the front side (201a) of the body (201), and a sliding knot (108) on the rear side (201b) of the body (201), and wherein the medical implant (1) comprises a second suture thread (300) extending through the sliding knot (108).

2. The medical implant according to claim 1, characterized in that the sliding knot (108) is configured to slide in a direction (S) pointing towards the rear side (201b) of the cortical fixation device (200) for tightening said twisted loop (104) and said non-twisted loop (105), wherein optionally the second suture (300) thread is configured to bring the sliding knot (108) away from the cortical fixation device (200) so as to loosen the twisted and non-twisted loop (104, 105).

3. The medical implant according to claim 1, characterized in that the first suture thread (100) comprises a first and a second free end (101, 102), wherein the free ends (101, 102) are threaded through the two through-holes (101, 102) such that the suture thread (100) forms said twisted loop (104) and said non-twisted loop (105) on the front side (201a) of the body (201).

4. The medical implant according to claim 3, characterized in that the first suture thread (100) comprises a turning loop (103) on the rear side (201b) of the body (201), wherein the turning loop (103) is formed into a Lark's head (106) which comprises two adjacent loops (107) through which said free ends (101, 102) are pulled so that said sliding knot (108) is formed on the rear side (201b) of the body (201).

5. The medical implant according to claim 4, characterized in that the second suture thread (300) extends through the two adjacent loops (107) of the Lark's head (106) such that the second suture thread (300) forms a loop.

6. The medical implant according to claim 1, characterized in that the front side (201a) of the body (201) comprises a slot (202) for receiving the first suture thread (100) for providing a knot-free fixation of the first suture thread (100) to the body (201), which slot (202) extends from the first through-hole (210) to the second through-hole (211).

7. The medical implant according to claim 6, characterized in that the front side (201a) comprises a recess (204), wherein an insert (205) is arranged in the recess (204), which insert (205) forms said slot (202) for receiving the first suture thread (100).

8. The medical implant according to claim 6, characterized in that the slot (202) comprises a structure (203) for enhancing friction, particularly in the form of a plurality of teeth (203), for securing the first suture thread (100).

9. The medical implant according to claim 3, characterized in that that the first free end (101) of the first suture thread (100) is passed through the first through-hole (210) so that the first suture thread (100) comprises a first loop (110) on the rear side (201b) of the body (201), and wherein the second free end (102) of the first suture thread (100) is passed through the second through-hole (211) so that the first suture thread (100) comprises a second loop (111) on the rear side (201b) of the body (201).

10. The medical implant according to claim 9, characterized in that for providing a knot-free fixation of the first suture thread (100), said first free end (101) is further passed through the second through-hole (211) so that a first portion (120) of the first suture thread (100) is embedded in said slot (202), wherein said second free end (102) is further passed through said first through-hole (210) so that a second portion (121) of the first suture thread (100) is embedded in said slot (202) so that the two portions (120, 121) extend along each other from opposite directions and are clamped in said slot (202).

11. The medical implant according to claim 9, characterized in that for shortening a length of the twisted loop (104) as well as a length of the non-twisted loop (105), the first and the second loop (110, 111) each comprise a section (130, 131) extending from said sliding knot (108), such that, when these sections (130, 131) are pulled away from the rear side (201b), particularly in an axial direction (A) along which said sections (130, 131) extend, said lengths decrease.

12. The medical implant according to claim 1, characterized in that for increasing the length of the twisted loop (104) and the length of the non-twisted loop (105), a first and a second free end (301, 302) of the second suture thread (300) are configured to be pulled away from the rear side (201b) in order to pull said sliding knot (108) away from the rear side (201b) such that said lengths are increased.

13. The medical implant according to claim 10, characterized in that for securing the twisted and the non-twisted loop (104, 105), the free ends (101, 102) of the first suture thread (100) are configured to be pulled away from the rear side (201b) such that the first and the second loop (110, 111) on the rear side (201b) are tightened while the twisted and the non-twisted loop (104, 105) are secured with help of said portions (120, 121) being arranged in said slot (202).

14. The medical implant according to claim 1, characterized in that the body (201) is formed as an elongated plate that extends along a longitudinal axis (L), wherein said through-holes (210, 211) are arranged side by side in the direction of said longitudinal axis (L).

15. The medical implant according to claim 7, characterized in that the insert (205) is formed out of a synthetic material, such as polyether ether ketone, polyethylene, ultra-high-molecular-weight polyethylene (UHMWPE), poly(propylene), poly(tetrafluoroethylene), poly(methyl methacrylate), ethylene-co-vinylacetate, poly(ether urethane), poly(ethylene terephthalate).

16. The medical implant according to claim 1, characterized in that the two through-holes (210, 220) are inner through holes (210, 211), wherein said body (201) comprises two outer through-holes (220, 221), wherein each outer through-hole (220, 221) extends from the front side (201a) to the rear side (201b), and wherein said outer through-holes (220, 221) face each other in the direction of the longitudinal axis (L), wherein the two inner through-holes (210, 211) are arranged between the two outer through-holes (220, 221).

17. The medical implant according to claim 16, characterized in that the inner diameter of the inner through-holes (210, 211) is larger than the inner diameter of the outer through-holes (220, 221).

18. The medical implant according to claim 1, characterized in that the body (201) is formed out of a metal and/or a synthetic material, wherein particularly said metal is one of: titanium alloy, stainless steel, cobalt-chrome alloy, nickel-titanium alloy, and wherein particularly said synthetic material is one of: biocompatible synthetic material, particularly a high strength biocompatible synthetic material, polyether ether ketone, ultra-high-molecular-weight polyethylene (UHMWPE), poly(tetrafluoroethylene).

19. The medical implant according to claim 1, characterized in that the twisted loop (104) and the non-twisted loop (105) are connected to said tendon or ligament graft (G) which extends through said twisted and non-twisted loop (104, 105).

20. A cortical fixation device (200) for fixing a ligament or tendon graft (G) in a desired position, comprising a body (201) having a front side (201a) and a rear side (201b), which rear side (201b) faces away from the front side (201a), and wherein said body (201) comprises a first and an adjacent second through-hole (210, 211), which through-holes (210, 211) extend from the front side (201a) to the rear side (201b) of said body (201), characterized in that the front side (201a) of the body (201) comprises a slot (202) for receiving a suture thread (100) for providing a knot-free fixation of the suture thread (100) to the body (201), which slot (202) extends from the first through-hole (210) to the second through-hole (211).

21. The cortical fixation device according to claim 20, characterized in that the front side (201a) comprises a recess (204), wherein an insert (205) is arranged in the recess (204), which insert (205) forms said slot (202) for receiving said suture thread (100).

22. The cortical fixation device according to claim 20, characterized in that the slot (202) comprises a structure for enhancing friction, particularly a plurality of teeth (203), for securing said suture thread (100).

23. The cortical fixation device according to claim 20, characterized in that the body (201) is formed as an elongated plate that extends along a longitudinal axis (L), wherein said through-holes (210, 211) are arranged side by side in the direction of said longitudinal axis (L).

24. The cortical fixation device according to claim 21, characterized in that the insert (205) is formed out of a synthetic material.

25. The cortical fixation device according to claim 20, characterized in that the two through-holes (210, 220) are inner through holes (210, 211), wherein said body (201) comprises two outer through-holes (220, 221), wherein each outer through-hole (220, 221) extends from the front side (201a) to the rear side (201b), and wherein said outer through-holes (220, 221) face each other in the direction of the longitudinal axis (L), wherein the two inner through-holes (210, 211) are arranged between the two outer through-holes (220, 221).

26. The cortical fixation device according to claim 25, characterized in that the inner diameter of the inner through-holes (210, 211) is larger than the inner diameter of the outer through-holes (220, 221).

27. The cortical fixation device according to claim 20, characterized in that the body (201) is formed out of a metal.

28. A method for fixing a ligament or tendon graft (G) in a desired position, wherein the method particularly uses a medical implant according to claim 1, wherein a first cortical fixation device (200) is provided that comprises a body (201) having a front side (201a) for butting against a bone to which the ligament or tendon graft (G) is to be fixed and a rear side (201b), which rear side (201b) faces away from the front side (201a), and a slot (202) optionally comprising a structure for enhancing friction (203) on the front side (201a), and wherein said body (201) comprises a first and an adjacent second through-hole (210, 211), which through-holes (210, 211) extend from the front side (201a) to the rear side (201b) of said body (201), wherein a first suture thread (100) is threaded to said through-holes (210, 211), and formed into a twisted twisted loop (104) and an non-twisted loop (105) being arranged on the first side (201a) of the body (201), wherein said twisted and said non-twisted loop (104, 105) are looped around a section of said ligament or tendon graft (G) to hold the latter and fix it to said bone, and wherein the first suture thread is tied to form a sliding knot (108) on the rear side (201b) of the body (201), and wherein a second suture thread (300) is threaded through said sliding knot (108) to allow loosening of the sliding knot (108), and wherein two portions (120, 121) of said first suture thread (100) are clamped within the said slot (202) for providing a knot-free fixation of the first suture thread (100) in said slot (202).

Description

[0065] Further features and advantages of the invention shall be described by means of detailed descriptions of embodiments with reference to the Figures, wherein

[0066] FIG. 1 shows a cortical fixation device (CFD) according to the invention,

[0067] FIG. 2 shows a medical implant according to the invention comprising a first CFD of FIG. 1 and a first suture thread pulled through the inner through-holes of the first CFD,

[0068] FIG. 3 shows the medical implant of FIG. 2 comprising a twisted and a non-twisted loop,

[0069] FIG. 4 shows the medical implant of FIG. 3, wherein the turning loop is formed into a Lark's head,

[0070] FIG. 5 shows the medical implant of FIG. 4, wherein the Lark's head forms a sliding knot together with the free ends of the first suture thread,

[0071] FIG. 6 shows the medical implant of FIG. 5, wherein here a second suture thread extends through the loops of the Lark's head,

[0072] FIG. 7 shows the medical implant of FIG. 6, wherein the free ends of the first suture thread are pulled through the inner through-holes for forming a first and a second loop on the rear side of the first CFD,

[0073] FIG. 8 shows the medical implant of FIG. 7, wherein the free ends of the first suture thread are further pulled through the respective other inner through-hole, wherein the size of the twisted and the non-twisted loop on the front side of the first CFD can be adjusted by pulling sections of the first and second loop on the rear side of the first CFD,

[0074] FIG. 9 shows the medical implant of FIG. 8, wherein the sliding knot is moved away from the rear side of the first CFD to loosen and particularly prolong the twisted and the non-twisted loop,

[0075] FIG. 10 shows the medical implant, wherein the second suture thread is removed,

[0076] FIG. 11 shows the medical implant of FIG. 10, wherein the first suture thread is secured by means of a slot of the first CFD,

[0077] FIG. 12 shows the medical implant of FIG. 11 with tightened sliding knot, the zoomed part shows two portions of the first suture thread that are embedded within the slot on the front side of the first CFD.

[0078] FIG. 13 shows an embodiment of the medical implant having two CFDs for fixing a graft/member that is connected to the CFDs via a first and a third suture thread, and

[0079] FIGS. 14-16 show an embodiment of a CFD according to the invention.

[0080] FIG. 1 shows in conjunction with FIGS. 14 to 16 and FIGS. 2 to 12 a medical implant 1 according to the invention which may comprise a graft G (cf. FIG. 13) or some other flexible (e.g. elongated) member for replacing a defect ligament or tendon, particularly an ACL, which can be connected to a twisted loop 104 and an non-twisted loop 105 formed by a first suture thread 100 of the implant 1.

[0081] The implant 1 comprises a first cortical fixation device (CFD) 200 which comprises four through-holes 210, 211, 220, 221, namely two inner through-holes 210, 211 and two optional outer through-holes 220, 221 having an inner diameter that is particularly smaller than the diameters of the inner through-holes 210, 211.

[0082] According to FIG. 1 said first cortical fixation device 200 comprises an e.g. elongate body 201 having a front side 201a and a rear side 201b, which rear side 201b faces away from the front side 201a. The front side 201a is configured to make contact with a bone (e.g. tibia or femur) in order to suspend the graft G (cf. FIG. 13) from the respective bone.

[0083] The through holes 210, 211, 220, 221 extend from said front side 201a to the rear side 201b of said body 201 of the first CFD 200.

[0084] Furthermore, the first side 201a comprises a slot 202 for receiving a first suture 100 thread 100 of the implant 1, which slot 202 extends on the first side 201a from the first through-hole 210 to the second through-hole 211. For fixing the first suture thread 100, the slot 202 preferably comprises a structure for enhancing friction, particularly plurality of teeth 203, which may extend perpendicular to the longitudinal axis L.

[0085] Particularly, as shown in FIGS. 14 to 16, the first side 201a of the body 201 may comprise a recess 204 (cf. FIG. 15), wherein an insert 205 (cf. FIG. 16) is arranged in the recess 204, which insert 205 forms said slot 202 for receiving the first suture thread 100, which slot comprises said teeth 203.

[0086] Particularly, in order to configure the implant 1 according to the invention, a first and a second free end of the first suture thread 100 are e.g. guided through the first inner through-hole 210 starting on the rear side 201b of the body 201. Then the two free ends 101, 102 are inserted into the other (second) inner through-hole 211 from the front side 201a and are pulled through, to establish the configuration shown in FIG. 2, which in detail comprises a twisted and a non-twisted loop 104, 105 (cf. FIG. 3) on the first side 201a of the first CFD 200 and a turning loop 103 and the two free ends 101, 102 of the first suture thread 100 on the rear side 201b of the body 201.

[0087] As shown in FIG. 4, the implant 1 further comprises a sliding knot 108 formed out of a Lark's head 106 that comprises two adjacent loops 107 through which the two free ends 101, 102 are pulled to form the knot 108.

[0088] For this, one may fold the turning loop 103 of the first suture thread 100 upwards in FIG. 3 and place it on top of the still aligned sections of the first suture thread 100 to achieve the configuration shown in FIG. 4, which comprises the two adjacent (e.g. raindrop-shaped) loops 107. Pulling the two free suture thread ends 101, 102 through the adjacent loops 107 yields a self-tightening sliding knot 108.

[0089] In order to add a loosening structure, i.e. a means to move/loosen the sliding knot 108, the implant 1 preferably comprises a second suture thread 300 which is inserted into the loops 107 of the sliding knot 108 as shown in FIG. 6.

[0090] The second suture thread 300 allows to pull the sliding knot 108, loosen the knot 108, and to elongate the twisted and non-twisted loop 104, 105 in order to adjust the loop length of the device 1. Thus, advantageously, the implant 1 according to the invention comprises a retightenable twisted and non-twisted loop 104, 105.

[0091] Particularly, in an embodiment, the sliding knot 108 is configured to slide in a direction S pointing towards the rear side 201b of the cortical fixation device 200 for tightening said twisted loop 104 and said non-twisted loop 105 against motion in the reverse direction R, wherein preferably the second suture thread 300 is configured to bring the sliding knot 108 away from the cortical fixation device 200 so as to loosen the twisted and the non-twisted loop 104, 105 and permit motion in the reverse direction R as indicated in FIG. 6.

[0092] Further, as shown in FIG. 7, the first free end 101 of the first suture thread 100 is inserted into the first inner through-hole 210 and the second free end 102 of said first suture thread 100 is inserted into the second inner through-hole 211 in order to create a first and a second loop 110, 11 of the first suture thread 100 on the rear side 201b of the body 201.

[0093] Then, the respective free end 101, 102 is pulled back through the respective other inner through-hole 211, 210 on the front side 201a of the body 201 of the first CFD 200, so that portions 120, 121 of the first suture thread lie on top of the structure/teeth 203 within the slot 202 of the first CFD 200 which is shown in FIG. 8 (cf. FIG. 12 for details).

[0094] Advantageously, said first and second loop 110, 111 enable a knot-free fixation by e.g. axial pulling.

[0095] To make the loop length of the twisted and the non-twisted loop 104, 105 shorter, the aligned sections 130, 131 of the first suture thread 100 extending from the sliding knot 108 can be pulled away (e.g. along axis A) from the rear side 201b of the body 201 as indicated in FIG. 8. It is possible to alternate pulling on each section 130, 131 incrementally.

[0096] In case an over-pulling situation happens, the surgeon can loosen the twisted and non-twisted loop 104, 105 by taking both free ends 301, 302 of the second suture thread 300 and by pulling them away from the rear side 201b of the body 201. The loosening effect elongates the loop length of the whole device 1, as shown in FIG. 9.

[0097] Once the desired length of the twisted and the non-twisted loop 104, 105 is achieved, the loop can be re-tightened again be repeating the step in FIG. 8. Then, the second suture thread 300 can be pulled out and discarded, e.g. by pulling on only one free end 301, 302, e.g. on free end 301 as indicated in FIG. 10.

[0098] In order to finally tighten the first and second loop 110, 111, both free ends 101, 102 can be taken and pulled in a direction away from the rear side 201b of the body 201 of the first CFD 200 as indicated in FIG. 11 (e.g. along axis A). In a clinical setting the direction in which the free ends 101, 102 of the first suture thread 100 need to be pulled could be e.g. in the axial direction A of the femoral tunnel FT (cf. e.g. FIG. 13).

[0099] Finally, the first suture thread 100 is secured by pulling (knot-free), wherein the securing effect stems from the friction at the portions 120, 121 that are embedded in the slot 202 comprising said structure/teeth 203 as shown in the detail of FIG. 12, and particularly the course of the first and second loop 110, 111. The secured implant 1 is shown in FIG. 12. For additional security, several half hitches in opposite directions with the free ends 101, 102 of the first suture thread 100 can be applied as an option.

[0100] The CFD 200 according to the invention is preferably used within the framework of the present invention. However, the configuration of the suture threads 100, 300 can also be combined with standard buttons/endobuttons, or any other compatible CFDs.

[0101] The implant 1 according to the invention can particularly be used for human or veterinary soft tissue such as tendon/ligament/synthetic graft fixation/repair/reconstruction on one side, or on both sides.

[0102] In this regard, FIG. 13 shows an example of a hamstring graft G that is held on both sides, namely by a first CFD 200 and a second CFD 400 that can be designed like the first CFD 200.

[0103] Particularly, here, the first suture thread 100 extends in a tibial tunnel TT that extends along axis A while a third suture thread 500 that may be configured as the first suture thread 100 (see FIG. 13) extends through a femural tunnel FT along axis A. Here, the first side 201a of the body 201 of the first CFD 200 butts against the tibia T, while the first side (with slot) of the body of the second CFT 400 butts against the femur F, so that the graft G is suspended from the CFTs 200, 400 via the first and third suture threads 100, 500.

[0104] The CFD 200, 400 according to the invention can be made of an (particularly biocompatible) metal such as titanium alloy, stainless steel, cobalt-chrome alloy, nickel-titanium alloy, etc. Or a preferably high strength biocompatible polymer, such as polyether ether ketone (PEEK), ultra-high-molecular-weight polyethylene (UHMWPE), poly(tetrafluoroethylene), etc., or a combination of both. FIGS. 14 to 16 show a hybrid design of the CFD 200, 400 already described above, wherein the body 201 can be made of a metal, while said insert 205 that may be connected to the body 201 e.g. by means of a force-fit connection can be made of a polymer. This design reduces the production barrier of a slot 202 with teeth 203 and allows to optimize/choose the slot size in order to fit/adapt with different suture threads 100, 500.