Locking line cutting device

Abstract

The invention relates to the field of medical instruments, in particular to a locking line cutting device which comprises a conveying pipe, a locking unit, a suture line and a pushing pipe, the locking unit comprises a locking sleeve and a matching part, the conveying pipe comprises a first groove, a second groove and a third groove, the first groove is formed in the far end of the second groove, and the suture line sequentially penetrates through the interior of the locking sleeve, the first groove, the second groove and the third groove. The suture located between the second groove and the third groove is arranged in the near-end direction of the matching piece; and the pushing pipe comprises a pushing part and a cutting piece arranged in the pushing part.

Description

Technical Field

[0001] The present invention belongs to the field of medical devices, and particularly relates to a thread locking and cutting device. Background Art

[0002] Sutures are widely used in patients to fix two or more layers of soft tissues together, or to fix soft tissues to bones. During open surgical procedures, large incisions provide ready access to the tissues, and it is not difficult for surgeons to pass sutures to the surgical site and then retrieve or withdraw the sutures to provide two free ends on either side of the tissue. Thereafter, the two ends of the suture are knotted or used for further suturing of the tissue. However, during interventional surgeries, such as performing foramen ovale tissue suture, mitral valve leaf suture, tricuspid valve leaf suture, or other endoscopic sutures, the fixation point of the suture is at the lesion location. The operator needs to complete the suture fixation and suture cutting at the lesion outside the body. Due to the limited access to the suture position, the suture is often difficult to handle, the suture effect cannot be guaranteed, and the suture is difficult to cut.

[0003] In the prior art, Patent CN2006800303544 discloses a knot placement device, including: a handle; an elongated shaft having a proximal end and a distal end and a lumen extending therethrough; a knot positioned within the distal end of the elongated shaft within the lumen; a pusher having a proximal end and a distal end slidably disposed within the lumen of the elongated shaft; and an actuator configured to advance the pusher relative to the distal end of the elongated shaft to distally engage the knot; an intermediate tube having a distal end and a proximal end concentrically and slidably disposed between the shaft and the pusher, the proximal end of the intermediate tube extending through the proximal end of the elongated shaft into the handle; the technical defect of this solution is that after the pusher pushes the plug into the knot body, it is necessary to push the intermediate tube to push out the joint and cut the suture. Therefore, at least three layers of pipe fittings are required to release the knot body, the assembly is complex, and two operating steps are required, and the thread locking and cutting cannot be completed in one step.

[0004] Therefore, how to design a device that can achieve thread locking and suture cutting in one operation is an urgent problem to be solved at present. Summary of the Invention

[0005] The object of the present invention is to overcome the deficiencies of the prior art and provide a thread locking and cutting device for the problem that the suture device cannot complete thread locking and cutting in one step.

[0006] The object of the present invention is achieved by the following solutions: A thread sewing and cutting device includes a conveying pipe, a locking unit, a sewing thread, and a pushing pipe. The locking unit includes a locking sleeve and a fitting. The conveying pipe includes a first groove, a second groove, and a third groove. The first groove is provided at the distal end of the second groove. The sewing thread sequentially passes through the inside of the locking sleeve, the first groove, the second groove, and the third groove. The sewing thread between the second groove and the third groove is arranged in the proximal direction of the fitting. Moreover, the pushing pipe includes a pushing part and a cutting part provided inside the pushing part.

[0007] The object of the present invention can also be further achieved by the following technical solutions: In one embodiment, the pushing part pushes the fitting to be connected with the locking sleeve, and the cutting part cuts off the sewing thread between the second groove and the third groove.

[0008] In one embodiment, when pre-assembled, the fitting is arranged at the proximal end of the locking sleeve or partially enters the locking sleeve.

[0009] In one embodiment, both the pushing step of the pushing part and the cutting action of the cutting part are achieved by pushing the pushing pipe.

[0010] In one embodiment, when the pushing pipe is pushed, the pushing part touches the fitting and pushes the fitting to be connected with the locking sleeve. After connection, the pushing pipe is continuously pushed. The locking sleeve and the fitting gradually leave the conveying pipe. During the leaving process, the cutting part moves to contact the sewing thread between the second groove and the third groove and completes the cutting step. After cutting, the pushing pipe is continuously pushed until the locking unit is separated from the conveying pipe.

[0011] In one embodiment, the distal end of the pushing part is arranged in the distal direction of the distal end of the cutting part, and the two are fixedly connected, and an axial safety distance is provided between the two. The safety distance is greater than the length of the fitting. The purpose of such a design is to prevent the cutting action of the sewing thread before the fitting completely enters the locking sleeve.

[0012] In one embodiment, the second groove and the third groove are arranged in parallel facing each other, and the central plane of the two is perpendicular to the cutting part. Moreover, the distance between the most distal end of the second groove and the most distal end of the conveying pipe is greater than the safety distance.

[0013] In one embodiment, the second groove and the third groove are symmetrically arranged about the center of the conveying pipe.

[0014] In one embodiment, the pushing pipe is sleeved inside the conveying pipe.

[0015] In one embodiment, the pushing tube includes a fourth groove and a fifth groove that are respectively parallel to the second groove and the third groove; and, the widths of the fourth groove and the fifth groove are greater than the widths of the second groove and the third groove.

[0016] In one embodiment, the second groove and the third groove are rectangular grooves or other closed-shaped grooves.

[0017] In one embodiment, the fourth groove and the fifth groove are U-shaped grooves or V-shaped grooves.

[0018] In one embodiment, the lengths of the fourth groove and the fifth groove are greater than the lengths of the second groove and the third groove.

[0019] In one embodiment, the proximal ends of the fourth groove and the fifth groove are in the proximal direction of the proximal end of the cutting member.

[0020] In one embodiment, during the process of pushing the pushing tube towards the distal end, the pushing portion first pushes the fitting member into the locking sleeve, cuts the suture when the cutting member touches the suture located between the second groove and the third groove, and the locking unit disengages from the delivery tube when the pushing portion moves to the distal end of the delivery tube.

[0021] In one embodiment, the center of the locking sleeve is hollow; and, the locking sleeve is pre-installed at the distal end of the delivery tube, the locking sleeve includes a cylinder and a distal step portion, and the length of the first groove is greater than the length of the cylinder.

[0022] In one embodiment, a small hole is provided at the distal end of the locking sleeve for passing the suture.

[0023] In one embodiment, the diameter of the small hole is smaller than the inner surface diameter of the cylinder.

[0024] In one embodiment, the fitting member includes a disc-shaped member and a wire-tightening portion provided at the distal end of the disc-shaped member; and, the diameter of the disc-shaped member does not exceed the size of the cylinder, and the wire-tightening portion fills the inner surface of the cylinder.

[0025] In one embodiment, the fitting member has a certain elasticity, and the fitting member is made of silica gel material.

[0026] In one embodiment, the fitting member includes a plurality of connecting units and fitting units, the connecting units are cylindrical, and the fitting units are in a combined shape of a cylinder and a frustum of a cone.

[0027] In one embodiment, it further includes a handle. The proximal ends of the delivery tube and the push tube are both connected to the handle. The handle includes a housing, a loading space, a squeezing member, an elastic member, a limiting member, and a control release unit. Moreover, the proximal end of the push tube is connected to the limiting member.

[0028] In one embodiment, the elastic member is pre-installed in the loading space. The limiting member is arranged at the distal end of the loading space, and the squeezing member is arranged at the proximal end of the loading space. By operating the squeezing member to enter the loading space, the elastic member is compressed.

[0029] In one embodiment, the squeezing member and the loading space are in a threaded connection.

[0030] In one embodiment, the control release unit is movably connected to the housing. When the limiting member is connected to the control release unit, the elastic member is in a compressed state. When operating the control release unit to separate from the limiting member, the elastic member returns to its natural state and moves towards the distal end, pushing the limiting member to move towards the distal end.

[0031] In one embodiment, a fixing buckle is arranged at the distal end of the control release unit. The fixing buckle clamps the limiting member so that the limiting member does not move axially.

[0032] In one embodiment, the compression amount of the elastic member is equal to the distance between the distal end of the pushing part and the distal end of the delivery tube.

[0033] In one embodiment, the proximal end of the suture, that is, the end outside the body, is pulled by the surgeon to keep it in a taut state.

[0034] In one embodiment, the suture is a two-strand thread, and the suture is folded in half after passing through the tissue to be repaired.

[0035] In one embodiment, the suture is composed of multiple threads, and the multiple threads are fixed at one place, and the fixing knot is located on the left atrial surface of the foramen ovale tissue.

[0036] In one embodiment, the delivery tube further includes a limiting track arranged at the proximal end of the second groove. The push tube includes an anti-disengagement block, and the anti-disengagement block moves in the limiting track and will not disengage from the delivery tube.

[0037] Compared with the prior art, the advantages of the present invention are as follows: 1. In the prior art, after the suture is locked, it is necessary to operate other components to cut the proximal end of the suture, so it is necessary to operate the handle at least twice to complete the fixation of the suture. Secondly, in the process of pushing the middle tube toward the distal end to cut the suture, since the middle tube has no driving force and the angle between the suture and the distal end of the middle tube is small, the middle tube may not be able to cut the suture, or because the force pushing the middle tube is too large, the middle tube may exceed the outer tube and scratch the heart tissue, causing secondary injury to the patient. The present application solves the above problems. First, the present application includes a delivery tube pre-installed with a locking unit and a push tube with a push portion and a cutting piece. The push tube moves toward the distal end under the action of elastic potential energy, which can not only push the matching piece into the locking sleeve, but also cut the suture. The present invention realizes the functions of thread locking and thread cutting in one operation step. Secondly, in the process of completing these two actions, only the push tube moves. Since the compression amount of the elastic member is equal to the distance between the distal end of the push part and the distal end of the delivery tube, the movement of the push tube will not exceed the delivery tube and will not damage the lesion tissue. Thirdly, since the second groove and the third groove are arranged in parallel opposite to each other, the center planes of the two are perpendicular to the cutting piece. The suture between the second groove and the third groove is perpendicular to the cutting piece in the axial direction, which ensures the cutting result. Fourthly, after the cutting piece cuts the suture, the push tube still moves toward the distal end, and the locking unit can be pushed out of the delivery tube. Thus, the movement of the push tube toward the distal end realizes the three functions of locking, thread cutting and ejection. The structural design is ingenious and simplifies the surgical steps.

[0038] 2. Different from the prior art, the distal end of the push part of the present application is set at the distal end of the cutting piece, the two are fixedly connected, and an axial safety distance is set between the two, which is greater than the length of the matching piece. The advantage of this design is that it ensures that the cutting piece can cut the suture only after the matching piece is completely inserted into the locking sleeve, ensuring the state of locking the suture; otherwise, the suture will be cut off in advance, and the locking sleeve and the matching piece have not been locked, or the suture in the locking sleeve will be loose, affecting the progress of the operation.

[0039] 3. Different from the prior art, the present application also designs the fourth and fifth grooves. The advantage of this design is that when the push tube pushes the mating piece toward the distal end, the sutures located in the second and third grooves will not interfere with the push part, ensuring that the push step is not hindered. At the same time, since the width of the fourth and fifth grooves is greater than that of the second and third grooves, the sutures located in the second and third grooves have a large space for movement.

[0040] 4. Different from the prior art, the handle of the present application includes a shell, a loading space, an extrusion member, an elastic member, a limiting member and a control release unit. By operating the control release unit, the push tube connected to the limiting member moves toward the distal end, and the movement stroke is equal to the compression amount of the elastic member. In addition, since the compression amount of the elastic member can be controlled by the operator by operating the extrusion member, the movement stroke of the push tube is also controllable, and the operability is strong.

[0041] 5. Different from the prior art, the thread-locking cutting device of the present application is suitable for in vivo knotting surgeries, such as valve leaflet closure and foramen ovale suture, and no matter how many sutures are there at the lesion, or where the lesion is located, it can be connected to the mating piece through the locking sleeve to achieve fixation.

[0042] 6. Different from the prior art, the delivery tube of the present application also includes a limit track arranged in the proximal direction of the second groove. The anti-slip block is connected with the limit track so that the push tube will not slip out of the limit track. The designer sets the length of the limit track and its distance from the end of the delivery tube to limit the movement of the push tube, which can further prevent the push tube from excessive movement, thereby preventing the risk of the distal end of the push tube scratching the tissue.

[0043] The embodiments of the present application can achieve other advantageous technical effects that are not listed one by one. These other technical effects may be partially described below and are predictable and understandable to those skilled in the art after reading this application. Brief Description of the Figures

[0044] The above features and advantages of these embodiments and other features and advantages and the ways to achieve them will be more obvious, and the embodiments of the present application can be better understood by referring to the following description together with the accompanying drawings, in which: Figures 1 - 3 This is a schematic diagram of the overall structure of the thread-locking cutting device of the present invention.

[0045] Figures 4 - 6 This is a schematic diagram of the working principle of the thread-locking cutting device of the present invention.

[0046] Figure 7 and Figure 8 This is a schematic diagram of the handle structure of the present invention.

[0047] Figure 9 is another embodiment of the present invention.

[0048] The names of the parts referred to by the numbers in the drawings are as follows: 1 - thread-locking cutting device, 2 - conveying tube, 21 - first groove, 22 - second groove, 23 - third groove, 24 - limiting track, 3 - locking unit, 31 - locking sleeve, 311 - small hole, 312 - cylinder, 313 - distal step portion, 32 - mating part, 321 - disc-shaped part, 322 - wire-tightening portion, 4 - suture, 5 - pushing tube, 51 - pushing portion, 52 - cutting part, 53 - safety distance, 54 - fourth groove, 55 - fifth groove, 56 - anti-disengagement block, 6 - handle, 61 - housing, 62 - loading space, 63 - pressing part, 64 - elastic part, 65 - limiting part, 66 - control release unit, 661 - fixing buckle. Embodiment

[0049] In the following description of the drawings and the specific embodiments, the details of one or more embodiments of the present application will be set forth. From these descriptions, the drawings, and the claims, other features, objects, and advantages of the present application will be apparent.

[0050] It should be understood that the embodiments illustrated and described are not limited in application to the details of the construction and arrangement of the components set forth in the following description or illustrated in the drawings. The illustrated embodiments may be other embodiments and can be implemented or carried out in various ways. The examples are provided by way of explanation of the disclosed embodiments rather than limitation. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present application without departing from the scope or essence of the disclosure of the present application. For example, features illustrated or described as part of one embodiment can be used with another embodiment to still produce additional embodiments. Accordingly, the disclosure of the present application covers such modifications and variations that fall within the scope of the appended claims and their equivalent elements.

[0051] Similarly, it can be understood that the phrases and terms used herein are for the purpose of description and should not be considered restrictive. The use of "including", "comprising", or "having" and their variants herein is intended to open-endedly include the items listed thereafter and their equivalents as well as additional items.

[0052] The present application will be described in more detail below with reference to different embodiments and examples of several aspects of the present application.

[0053] In the present application, the terms "proximal" or "proximal side" refer to the end or side closer to the surgical operator, and "distal" or "distal side" refer to the end or side farther from the surgical operator. Embodiment 1

[0054] As Figures 1 to 3As shown in the figure, a thread-locking and cutting device 1 is illustrated, which includes a conveying pipe 2, a locking unit 3, a sewing thread 4, and a pushing pipe 5. The locking unit 3 includes a locking sleeve 31 and a fitting 32. The conveying pipe 2 includes a first groove 21, a second groove 22, and a third groove 23. The first groove 21 is provided at the distal end of the second groove 22. The sewing thread 4 sequentially passes through the inside of the locking sleeve 31, the first groove 21, the second groove 22, and the third groove 23. The sewing thread 4 between the second groove 22 and the third groove 23 is arranged in the proximal direction of the fitting 32, as Figure 4 shown; and the pushing pipe 5 includes a pushing portion 51 and a cutting member 52 provided inside the pushing portion 51.

[0055] The composition and connection methods of each component in this embodiment will be described in detail below with reference to the accompanying drawings: In this embodiment, the pushing portion 51 pushes the fitting 32 to be connected with the locking sleeve 31, and the cutting member 52 cuts off the sewing thread 4 between the second groove 22 and the third groove 23.

[0056] In this embodiment, when pre-installed, the fitting 32 is arranged at the proximal end of the locking sleeve 31 or partially enters the locking sleeve 31.

[0057] In this embodiment, both the pushing step of the pushing portion 51 and the cutting action of the cutting member 52 are realized by pushing the pushing pipe 5.

[0058] In this embodiment, when the pushing pipe 5 is pushed, the pushing portion 51 touches the fitting 32 and pushes the fitting 32 to be connected with the locking sleeve 31. After the connection, the pushing pipe 5 is continuously pushed. The locking sleeve 31 and the fitting 32 gradually leave the conveying pipe 2. During the leaving process, the cutting member 52 moves to contact the sewing thread 4 between the second groove 22 and the third groove 23 and completes the cutting step. After the cutting, the pushing pipe 5 is continuously pushed until the locking unit 3 is separated from the conveying pipe 2, as Figures 4 to 6 shown.

[0059] In this embodiment, the distal end of the pushing portion 51 is arranged in the distal direction of the distal end of the cutting member 52. The two are fixedly connected, and an axial safety distance 53 is provided between the two. The safety distance 53 is greater than the length of the fitting 32. The purpose of such a design is to prevent the cutting action of the sewing thread 4 before the fitting 32 completely enters the locking sleeve 31, as Figure 3 shown.

[0060] In this embodiment, the second groove 22 and the third groove 23 are arranged parallel to each other and face each other, and their central planes are perpendicular to the cutting member 52; moreover, the distance between the farthest ends of the second groove 22 and the farthest end of the conveying pipe 2 is greater than the safety distance 53.

[0061] In this embodiment, the second groove 22 and the third groove 23 are arranged symmetrically about the center of the conveying pipe 2.

[0062] In this embodiment, the pushing pipe 5 is sleeved inside the conveying pipe 2.

[0063] In this embodiment, the pushing pipe 5 includes a fourth groove 54 and a fifth groove 55 that are respectively parallel to the second groove 22 and the third groove 23; moreover, the widths of the fourth groove 54 and the fifth groove 55 are greater than the widths of the second groove 22 and the third groove 23.

[0064] In this embodiment, the second groove 22 and the third groove 23 are rectangular grooves; the fourth groove 54 and the fifth groove 55 are U-shaped grooves.

[0065] In this embodiment, the lengths of the fourth groove 54 and the fifth groove 55 are greater than the lengths of the second groove 22 and the third groove 23.

[0066] In this embodiment, the proximal ends of the fourth groove 54 and the fifth groove 55 are in the proximal direction of the proximal end of the cutting member 52.

[0067] In this embodiment, during the process of pushing the pushing pipe 5 to move towards the distal end, the pushing portion 51 first pushes the cooperating member 32 into the locking sleeve 31, as Figure 5 shown, when the cutting member 52 touches the sewing thread 4 located between the second groove 22 and the third groove 23, the sewing thread 4 is cut, and when the pushing portion 51 moves to the distal end of the conveying pipe 2, the locking unit 3 disengages from the conveying pipe 2, as Figure 6 shown.

[0068] In this embodiment, the center of the locking sleeve 31 is hollow; moreover, the locking sleeve 31 is pre-installed at the distal end of the conveying pipe 2, the locking sleeve 31 includes a cylinder 312 and a distal step portion 313, and the length of the first groove 21 is greater than the length of the cylinder 312.

[0069] In this embodiment, the distal end of the locking sleeve 31 is provided with a small hole 311 for passing the sewing thread 4; moreover, the diameter of the small hole 311 is smaller than the inner surface diameter of the cylinder 312, as Figure 4 shown.

[0070] In this embodiment, the fitting 32 includes a disc-mounted part 321 and a tightening part 322 disposed at the distal end of the disc-mounted part 321; and the diameter of the disc-mounted part 321 does not exceed the size of the cylinder 312, and the tightening part 322 fills the inner surface of the cylinder 312.

[0071] In this embodiment, a handle 6 is further included. The proximal ends of the delivery tube 2 and the push tube 5 are both connected to the handle 6. The handle 6 includes a housing 61, a loading space 62, an extrusion member 63, an elastic member 64, a restriction member 65, and a control release unit 66; and the proximal end of the push tube 5 is connected to the restriction member 65, as shown in Figure 7 and Figure 8 As shown.

[0072] In this embodiment, the elastic member 64 is pre-installed in the loading space 62, the limiting member 65 is arranged at the distal end of the loading space 62, and the extruding member 63 is arranged at the proximal end of the loading space 62. The elastic member 64 is compressed by operating the extruding member 63 to enter the loading space 62.

[0073] In this embodiment, the extrusion member 63 is threadedly connected to the loading space 62.

[0074] In this embodiment, the control release unit 66 is movably connected to the housing 61. When the limiting member 65 is connected to the control release unit 66, the elastic member 64 is in a compressed state. When the control release unit 66 is separated from the limiting member 65, the elastic member 64 moves toward the distal end to restore the natural state and push the limiting member 65 to move toward the distal end.

[0075] In this embodiment, a fixing buckle 661 is provided at the distal end of the control release unit 66, and the fixing buckle 661 clamps the limiting member 65 so that the limiting member 65 does not move axially.

[0076] In this embodiment, the compression amount of the elastic member 64 is equal to the distance between the distal end of the pushing portion 51 and the distal end of the delivery tube 2.

[0077] In this embodiment, the proximal end of the suture 4, i.e., the end outside the body, is pulled by the operator to keep it in a taut state.

[0078] In this embodiment, the suture 4 is composed of three threads, and the multiple threads are fixed to the distal surface of the tissue to be repaired.

[0079] The working process steps of the present invention are as follows: (1) Tighten the suture 4 proximally, operate the control release unit 66 of the handle 6 so that the elastic member 64 is unrestricted, the elastic member 64 returns to its original state, and the elastic member 64 drives the push tube 5 to move distally; (2) During the movement of the push tube 5 distally, the pushing portion 51 pushes the mating member 32 to connect with the locking sleeve 31, the cutting member 52 cuts the suture 4 located between the second groove 22 and the third groove 23, and the locking unit 3 is pushed out by the pushing portion 51; (3) Recover a part of the suture 4 and the suture locking and cutting device 1 controlled by the operator to complete the implantation. Embodiment 2

[0080] The difference from Embodiment 1 is that: In this embodiment, the delivery tube 2 further includes a limiting track 24 provided in the proximal direction of the second groove 22. The push tube 5 includes an anti - detachment block 56. The anti - detachment block 56 moves within the limiting track 24, and the anti - detachment block 56 does not detach from the delivery tube 2.

[0081] This embodiment discloses a suture locking and cutting device 1, including a delivery tube 2, a locking unit 3, a suture 4 and a push tube 5. The locking unit 3 includes a locking sleeve 31 and a mating member 32. The delivery tube 2 includes a first groove 21, a second groove 22 and a third groove 23. The first groove 21 is provided at the distal end of the second groove 22. The suture 4 sequentially passes through the inside of the locking sleeve 31, the first groove 21, the second groove 22 and the third groove 23. The suture 4 located between the second groove 22 and the third groove 23 is arranged in the proximal direction of the mating member 32, as Figure 4 shown; and the push tube 5 includes a pushing portion 51 and a cutting member 52 provided within the pushing portion 51.

[0082] In the second embodiment, the delivery tube 2 includes two such limiting tracks 24, and the push tube 5 includes two such anti - detachment blocks 56, as Figure 9 shown.

[0083] In the second embodiment, the compression amount of the elastic member 64 is greater than the distance between the distal end of the pushing portion 51 and the distal end of the delivery tube 2. Thus, the cutting force received by the suture 4 is large, further ensuring the occurrence of the cutting action.

[0084] In the second embodiment, the anti - detachment block 56 and the pushing portion 51 are detachably connected.

[0085] In the second embodiment, when the push tube 5 is loaded inside the delivery tube 2, the anti - detachment block 56 extends beyond the outer periphery of the push tube 5 and fits with the delivery tube 2.

[0086] The above content is only a preferred embodiment of the present invention. For those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manners and application scopes. The content of this specification should not be construed as a limitation to the present invention.

Claims

1. A thread-locking cutting device, characterized in that: It includes a delivery tube, a locking unit, a suture and a push tube, the locking unit includes a locking sleeve and a matching piece, the delivery tube includes a first groove, a second groove and a third groove, the first groove is arranged at the distal end of the second groove, the suture passes through the interior of the locking sleeve, the first groove, the second groove and the third groove in sequence, and the suture located between the second groove and the third groove is arranged in the proximal direction of the matching piece; and the push tube includes a push part and a cutting piece arranged in the push part.

2. The thread-locking cutting device according to claim 1, characterized in that: The pushing part pushes the matching piece to connect with the locking sleeve, and the cutting piece cuts the suture between the second groove and the third groove; and when the matching piece is pre-installed, it is arranged at the proximal end of the locking sleeve or partially enters the locking sleeve.

3. The thread-locking cutting device according to claim 1, characterized in that: The distal end of the pushing portion is arranged in the distal direction of the distal end of the cutting piece, the two are fixedly connected, and an axial safety distance is arranged between the two, and the safety distance is greater than the length of the matching piece.

4. The thread-locking cutting device according to claim 3, characterized in that: The second groove and the third groove are arranged in parallel and opposite to each other, and the center planes of the two grooves are perpendicular to the cutting piece; and the distance between the farthest end of the second groove and the farthest end of the conveying tube is greater than the safety distance.

5. The thread-locking cutting device according to claim 1, characterized in that: The push tube includes a fourth groove and a fifth groove which are parallel to the second groove and the third groove respectively; and the width of the fourth groove and the fifth groove is greater than the width of the second groove and the third groove.

6. The thread-locking cutting device according to claim 1, characterized in that: In the process of pushing the pushing tube toward the distal end, the pushing portion first pushes the matching piece into the locking sleeve, and cuts the suture when the cutting piece touches the suture between the second groove and the third groove, and the locking unit disengages from the conveying tube when the pushing portion moves to the distal end of the conveying tube.

7. The thread-locking cutting device according to claim 1, characterized in that: The center of the locking sleeve is hollowed out; and the locking sleeve is pre-installed on the distal end of the delivery tube, the locking sleeve comprises a cylinder and a distal step portion, and the length of the first groove is greater than the length of the cylinder.

8. The thread-locking cutting device according to claim 7, characterized in that: The fitting part comprises a disk-shaped part and a tightening wire portion arranged at the distal end of the disk-shaped part; and the diameter of the disk-shaped part does not exceed the size of the cylinder, and the tightening wire portion fills the inner surface of the cylinder.

9. The thread-locking cutting device according to claim 1, characterized in that: It also includes a handle, the proximal ends of the delivery tube and the push tube are both connected to the handle, the handle includes a shell, a loading space, an extrusion member, an elastic member, a restriction member and a control release unit; and the proximal end of the push tube is connected to the restriction member.

10. The thread-locking cutting device according to claim 9, characterized in that: The elastic member is pre-installed in the loading space, the limiting member is arranged at the distal end of the loading space, and the extruding member is arranged at the proximal end of the loading space. The elastic member is compressed by operating the extruding member to enter the loading space.

11. The thread-locking cutting device according to claim 9, characterized in that: The control release unit is movably connected to the shell. When the restriction member is connected to the control release unit, the elastic member is in a compressed state. When the control release unit is operated to separate from the restriction member, the elastic member recovers its natural state and moves toward the distal end and pushes the restriction member to move toward the distal end. Moreover, the compression amount of the elastic member is equal to the distance between the distal end of the pushing portion and the distal end of the delivery tube.

12. The thread-locking cutting device according to claim 1, characterized in that: The delivery tube further comprises a limiting track arranged in the proximal direction of the second groove, and the push tube comprises an anti-slip block, which moves within the limiting track and will not detach from the delivery tube.

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