Ligament fixation screw

Abstract

The application relates to the field of medical devices, in particular to a ligament fixation screw. The ligament fixation screw comprises a shank, a cap and a washer; the cap comprises an end plate and a guide pipe arranged on one side of the end plate, a boss and a wire pressing groove are arranged in the guide pipe; a wire pressing head corresponding to the wire pressing groove is arranged on the washer, and the wire pressing head exerts extrusion force on an implant when the wire pressing head cooperates with the wire pressing groove; the implant extends to the space between the washer and the end plate and is fixed; the shank penetrates through the washer and is screwed with the cap. The unique structural design effectively improves the fixing stability and operation convenience of the implant and prolongs the service life of the device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a ligament fixation screw. BACKGROUND

[0002] In ligament repair surgery, fixation screws are widely used to fix the graft on the bone. At the same time, in order to ensure the stability of the fixation screw, a cap is also used, that is, the cap is implanted on the bone first, and the fixation screw is installed on the cap, so as to fix the implant replacing the ligament on the bone. The traditional ligament fixation screw usually adopts a straight implantation method, that is, the implantation direction of the cap is consistent with the screw rotation direction. This method may cause insufficient fixation in some cases, the graft is easy to move or pull out, and the screw fixation effect needs to be improved.

[0003] Therefore, the patent application with publication number WO2020127667A1 specifically discloses a medical fixation device for fixing a graft, in which scheme, the cap and the screw rotation direction have a certain angle, so as to obtain a better fixation effect and have higher stability. In this technical scheme, a gasket is also provided, which is fixed by the screw, so that the gasket cooperates with the cap and is fixed, and the implant is fixed by the extrusion of the gasket and the cap.

[0004] However, the existing fixation screw still has some deficiencies in actual application. Especially when the gasket and the cap are used for fixation, the gasket and the cap will have a large extrusion effect on the implant, causing deformation of the implant. Such deformation not only affects the mechanical properties of the implant, but also causes friction between the implant and the edge of the gasket and the cap due to the action of alternating tension on the implant during the movement of the user, accelerating the wear of the implant, thereby shortening its service life. Therefore, how to reduce the damage to the implant while ensuring the stability of the fixation screw has become a technical problem to be solved. SUMMARY

[0005] The present application provides a ligament fixation screw with high stability, which can reduce the wear of the implant and improve the service life. The following technical scheme is adopted:

[0006] A ligament fixation screw, comprising a shank, a cap and a gasket;

[0007] The cap comprises an end plate and a guide pipe arranged on one side of the end plate; a boss is arranged in the guide pipe, and a wire pressing groove is formed in the boss;

[0008] The end plate is provided with a seal that matches the catheter, and the gasket matches the seal; the gasket is provided with a wire pressing head corresponding to the wire pressing groove; the inner wall of the wire pressing groove and the surface of the wire pressing head are both arc surfaces; when the wire pressing head matches the wire pressing groove, a gap is left between the surface of the wire pressing head and the inner wall of the wire pressing groove, and the wire pressing head and the wire pressing groove apply an extrusion force to the implant;

[0009] The implant extends between the washer and the end plate, and the washer and the end plate cooperate to achieve fixation of the implant;

[0010] The nail body passes through the washer and is screwed to the sealing cap.

[0011] By adopting the above technical solution, the implant can be initially fixed by the combination of the crimping head and the crimping groove. The inner wall of the crimping groove and the surface of the crimping head are both curved, which can reduce friction on the implant. The implant can then be re-fixed by the combination of the washer and the end plate, further ensuring the stability and durability of the implant.

[0012] Preferably, the gasket includes a first pressing piece and a second pressing piece, the pressing head is provided on the first pressing piece, and the implant extends between the first pressing piece and the second pressing piece.

[0013] By adopting the above technical solution, the implant is clamped by the first pressing plate and the second pressing plate, which can further improve the stability and durability of the implant.

[0014] Preferably, a wire groove is provided at the edge of the first pressing sheet, and the implant extends between the first pressing sheet and the second pressing sheet through the wire groove.

[0015] By adopting the above technical solution, the setting of the wire groove can avoid excessive squeezing of the gasket and end plate on the implant, thus ensuring that the implant has sufficient strength. At the same time, the implant is bent at the position of the wire pressing head and the position at the edge of the gasket, so there is a high friction between the implant and the sealing cap, further improving the stability of the implant.

[0016] Preferably, there are two implants, and two corresponding wire grooves are provided. The two implants pass through the two wire grooves respectively and engage with the wire grooves. The part of the implant located in the wire groove is squeezed by the side wall of the wire groove.

[0017] By adopting the above technical solution, the two wire grooves are distributed independently, thereby separating the two implants, which can effectively increase the contact area between the gasket and the implant and improve the fixation effect.

[0018] Preferably, the first pressing plate and the second pressing plate are both provided with wire pressing teeth on the side walls opposite to each other.

[0019] By adopting the technical scheme, the setting of the line pressing teeth can effectively improve the fixing effect of the first pressing plate and the second pressing plate on the implant and improve the stability of the implant.

[0020] Preferably, opposite side walls of the first pressing plate and the second pressing plate are further provided with accommodating grooves, and the implant is arranged in the accommodating grooves; and the line pressing teeth are arranged in the accommodating grooves.

[0021] By adopting the technical scheme, the accommodating grooves provide space for placing the implant, avoid excessive extrusion of the first pressing plate and the second pressing plate on the implant, and ensure the strength of the implant.

[0022] Preferably, an edge of the second pressing plate is provided with a buried line groove, and the end of the implant is located in the buried line groove.

[0023] By adopting the technical scheme, since the implant is relatively long, the implant needs to be cut after being fixed. The implant passes through the buried line groove and is cut close to the gasket, so as to reduce the residual length of the cut implant. In addition, if the residual part of the implant is relatively long, the residual part can also be inserted into the buried line groove to realize no residual or less residual of the cut implant and improve the use performance.

[0024] Preferably, the shank includes a first segment and a second segment, a first insertion hole is arranged on the first pressing plate, the first insertion hole is in plug-in cooperation with the first segment, and the diameter of the first insertion hole is smaller than the diameter of the second segment; a deformation seam is further arranged on the first pressing plate, the deformation seam is in communication with the first insertion hole, and the position between adjacent two deformation seams is a deformation part.

[0025] A second insertion hole is arranged on the second pressing plate, and the second insertion hole is in plug-in cooperation with the second segment.

[0026] By adopting the technical scheme, in the initial state, the first pressing plate and the second pressing plate are separated and have a gap. With the screwing of the shank, the stepped surface between the first segment and the second segment pushes the first pressing plate and the line pressing head to tightly fix the implant. Then, when the shank is continuously screwed, the deformation part deforms to make the second segment cooperate with the first insertion hole, and the first pressing plate and the second pressing plate abut against each other, so as to clamp and fix the implant located therebetween, thereby realizing the fixation of the implant.

[0027] Preferably, the inner wall of the sealing cover has a first plane, the side walls of the first pressing plate and the second pressing plate are correspondingly provided with a second plane, and the first plane and the second plane abut against each other when the first pressing plate and the second pressing plate cooperate with the sealing cover.

[0028] By adopting the technical scheme, the first pressing plate and the second pressing plate can only translate through cooperation of the first plane and the second plane, so that the first pressing plate and the second pressing plate are prevented from rotating with the nail body when the nail body is screwed, thereby facilitating fixation of the implant.

[0029] In summary, the present application has at least one of the following beneficial technical effects:

[0030] 1. By cooperation of the wire pressing head and the wire pressing groove, appropriate extrusion force can be applied to the implant when the implant enters the wire pressing groove, so that preliminary fixation is achieved, over-extrusion and deformation of the implant are reduced, and mechanical properties and service life of the implant are improved;

[0031] 2. The inner wall of the wire pressing groove and the surface of the wire pressing head are both arc surfaces, so that friction between the implant, the gasket and the cap is reduced, wear of the implant during movement is reduced, and service life of the implant is prolonged;

[0032] 3. By cooperation of the gasket and the end plate, secondary fixation of the implant is achieved, fixation effect is enhanced, stability and durability of the overall structure are improved, and clinical requirements are better met. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 is a schematic diagram of the overall structure of the ligament fixation screw in the embodiment of the present application;

[0034] Figure 2 is a sectional view of the ligament fixation screw in the embodiment of the present application;

[0035] Figure 3 is a schematic diagram of the exploded structure of the ligament fixation screw in the embodiment of the present application;

[0036] Figure 4 is a schematic diagram of the exploded structure of the ligament fixation screw in the embodiment of the present application.

[0037] In the drawings, 1 is a nail body, 11 is a first segment, 12 is a second segment, 2 is a cap, 21 is an end plate, 211 is a sealing portion, 212 is a first plane, 22 is a guide pipe, 23 is a boss, 231 is a wire pressing groove, 3 is a gasket, 31 is a first pressing plate, 311 is a wire passing groove, 312 is a deformation seam, 32 is a second pressing plate, 321 is a wire embedding groove, 33 is a wire pressing head, 34 is a containing groove, and 35 is a second plane. DETAILED DESCRIPTION

[0038] The following will be described in detail with reference to the accompanying drawings Figures 1-4 The present application will be further described in detail.

[0039] The ligament fixation screw provided in the embodiment of the present application, with reference to Figure 1 and Figure 2, including a nail body 1, a cap 2 and a gasket 3. The cap 2 comprises an end plate 21 and a guide pipe 22 arranged on one side of the end plate 21; the guide pipe 22 is provided with a boss 23, and the boss 23 is provided with a wire pressing groove. The end plate 21 is provided with a sealing hole 211 which is in communication with the guide pipe 22, and the gasket 3 is matched with the sealing hole 211. The gasket 3 is provided with a wire pressing head 33 which is matched with the wire pressing groove; the inner wall of the wire pressing groove and the surface of the wire pressing head 33 are both arc surfaces; when the wire pressing head 33 is matched with the wire pressing groove, a gap is left between the surface of the wire pressing head 33 and the inner wall of the wire pressing groove, and the wire pressing head 33 and the wire pressing groove exert an extrusion force on the implant, so as to preliminarily fix the implant. The nail body 1 passes through the gasket 3 and is screwed with the cap 2, so as to relatively fix the gasket 3 and the end plate 21 and secondarily fix the implant.

[0040] Specifically, the nail body 1 comprises a first segment 11 and a second segment 12; the diameter of the first segment 11 is smaller, and the diameter of the second segment 12 is larger; and a stepped surface is formed between the first segment 11 and the second segment 12. The gasket 3 comprises a first pressing piece 31 and a second pressing piece 32, and the wire pressing head 33 is arranged on the first pressing piece 31. The first pressing piece 31 is provided with a first insertion hole, the first insertion hole is matched with the first segment 11 in a plug-in manner, and the diameter of the first insertion hole is smaller than the diameter of the second segment 12. The second pressing piece 32 is provided with a second insertion hole, and the second insertion hole is matched with the second segment 12 in a plug-in manner.

[0041] In an initial state, the first pressing piece 31 and the second pressing piece 32 are separated and have a gap. With the screwing of the nail body 1, the stepped surface between the first segment 11 and the second segment 12 pushes the first pressing piece 31 to move close to the boss 23, and the wire pressing head 33 is matched with the groove; at this time, the implant is located in the groove, so that the wire pressing head 33 can press the implant into the groove, and the wire pressing head 33 exerts a clamping force on the implant, thereby realizing the fixation of the implant.

[0042] Subsequently, with the continuous screwing of the nail body 1, the nail body 1 moves relative to the first pressing piece 31, and the first pressing piece 31 moves to the second segment 12.

[0043] Referring to Figure 3 and Figure 4 , in order to facilitate the cooperation between the first pressing piece 31 and the second segment 12, the first pressing piece 31 is further provided with a deformation seam 312 which is in communication with the first insertion hole, so as to form a plurality of deformation portions around the first insertion hole.

[0044] During the relative movement between the nail body 1 and the first pressing piece 31, the deformation portions are deformed, so that the second segment 12 is matched with the first insertion hole; with the continuous screwing of the nail body 1, the second pressing piece 32 is tightly attached to the first pressing piece 31; before this, the implant needs to be arranged between the first pressing piece 31 and the second pressing piece 32, so that the first pressing piece 31 and the second pressing piece 32 can clamp and fix the implant.

[0045] The inner wall of the sealing cap 211 has a first plane 212, and the side wall of the first pressing piece 31 and the second pressing piece 32 is correspondingly provided with a second plane 35, and when the first pressing piece 31 and the second pressing piece 32 are matched with the sealing cap 211, the first plane 212 and the second plane 35 abut. Through the cooperation of the first plane 212 and the second plane 35, the first pressing piece 31 and the second pressing piece 32 can only be translated, avoiding the first pressing piece 31 and the second pressing piece 32 from rotating with the nail body 1 when the nail body 1 is screwed, thereby facilitating the fixation of the implant.

[0046] Through the cooperation of the wire pressing head 33 and the wire pressing groove, the implant can be preliminarily fixed, and the inner wall of the wire pressing groove and the surface of the wire pressing head 33 are both arc surfaces, which can reduce the friction on the implant. And through the cooperation of the gasket 3 and the end plate 21, the implant is fixed again, further ensuring the stability and durability of the implant. The implant is gradually fixed, further improving the fixation effect and reliability.

[0047] Further, the edge of the first pressing piece 31 is provided with a wire passing groove 311, and the implant extends to the space between the first pressing piece 31 and the second pressing piece 32 through the wire passing groove 311. The wire passing groove 311 can avoid the excessive extrusion of the gasket 3 and the end plate 21 on the implant, thereby ensuring that the implant has sufficient strength. At the same time, the implant is located at the position of the wire pressing head 33 and the position of the edge of the gasket 3, and both positions are bent, so that the implant has high friction with the sealing cap 2, further improving the stability of the implant.

[0048] In the embodiment of the application, the wire passing groove 311 can be one or two. Since the implant needs to be folded in specific use, the implant is provided with two. When the wire passing groove 311 is one, the two implants are arranged in the wire passing groove 311. When the wire passing groove 311 is two, the two implants pass through the two wire passing grooves 311 and are clamped and matched with the wire passing grooves 311. Specifically, the two wire passing grooves 311 are independently distributed, so that the two implants are separated, which can effectively increase the contact area of the gasket 3 and the implant and improve the fixation effect.

[0049] In addition, whether the wire passing groove 311 is one or two, the part of the implant located in the wire passing groove 311 will be extruded by the side wall of the wire passing groove 311, increasing the friction between the implant and the gasket 3 and further improving the stability of the implant.

[0050] The opposite side walls of the first pressing sheet 31 and the second pressing sheet 32 are also provided with accommodating grooves 34, in which the implants are arranged. The accommodating grooves 34 provide space for the placement of the implants, avoid excessive extrusion of the implants by the first pressing sheet 31 and the second pressing sheet 32, and ensure the strength of the implants. The accommodating grooves 34 are also provided with pressing line teeth, which can occlusively fix the implants, and further enhance the fixing effect of the implants.

[0051] Further, the edge of the second pressing sheet 32 is provided with an implant embedding groove 321, in which the end of the implant is arranged. The arrangement of the implant embedding groove 321 enables the implant to be closely cut against the gasket 3 when the implant needs to be cut after being fixed, thereby reducing the residual length of the implant after cutting. In addition, if the residual part of the implant is relatively long, the residual part can also be inserted into the implant embedding groove 321 to achieve no residual or less residual of the implant after cutting, and improve the use performance.

[0052] The embodiments of the specific implementation are the preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore, any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A ligament fixation screw, characterized in that: It comprises a nail body (1), a sealing cap (2) and a washer (3); The sealing cap (2) comprises an end plate (21) and a conduit (22) provided on one side of the end plate (21); a boss (23) is provided in the conduit (22), and a wire pressing groove is provided on the boss (23); The end plate (21) is provided with a sealing opening (211) that matches the catheter (22), and the gasket (3) matches the sealing opening (211); the gasket (3) is provided with a wire pressing head (33) corresponding to the wire pressing groove; the inner wall of the wire pressing groove and the surface of the wire pressing head (33) are both cambered surfaces; when the wire pressing head (33) matches the wire pressing groove, a gap is left between the surface of the wire pressing head (33) and the inner wall of the wire pressing groove, and the wire pressing head (33) and the wire pressing groove apply an extrusion force to the implant; The implant extends between the washer (3) and the end plate (21), and the washer (3) and the end plate (21) cooperate to achieve fixation of the implant; The nail body (1) passes through the washer (3) and is screwed to the sealing cap (2); The washer (3) comprises a first pressing piece (31) and a second pressing piece (32), the pressing head (33) is provided on the first pressing piece (31), and the implant extends between the first pressing piece (31) and the second pressing piece (32); The nail body (1) comprises a first segment (11) and a second segment (12); a first insertion hole is provided on the first pressing plate (31), the first insertion hole is plugged into the first segment (11), and the diameter of the first insertion hole is smaller than the diameter of the second segment (12); a deformation seam (312) is also provided on the first pressing plate (31), the deformation seam (312) is connected to the first insertion hole, and the position between two adjacent deformation seams (312) is a deformation portion; A second jack is provided on the second pressing plate (32), and the second jack is plug-fitted to the second segment (12).

2. The ligament fixation screw according to claim 1, characterized in that: A wire groove (311) is provided at the edge of the first pressing sheet (31), and the implant extends between the first pressing sheet (31) and the second pressing sheet (32) via the wire groove (311).

3. The ligament fixation screw according to claim 2, characterized in that: Two implants are provided, and two corresponding wire grooves (311) are provided. The two implants pass through the two wire grooves (311) respectively and are engaged with the wire grooves (311). The portion of the implant located in the wire grooves (311) is squeezed by the side walls of the wire grooves (311).

4. The ligament fixation screw according to claim 1, characterized in that: Wire pressing teeth are provided on the opposite side walls of the first pressing plate (31) and the second pressing plate (32).

5. The ligament fixation screw according to claim 4, characterized in that: The side walls opposite to the first pressing plate (31) and the second pressing plate (32) are further provided with a receiving groove (34), and the implant is arranged in the receiving groove (34); the wire pressing teeth are arranged in the receiving groove (34).

6. The ligament fixation screw according to claim 1, characterized in that: A wire embedding groove (321) is provided at the edge of the second pressing sheet (32), and the end of the implant is located inside the wire embedding groove (321).

7. The ligament fixation screw according to claim 1, characterized in that: The inner wall of the seal (211) has a first plane (212), and the side walls of the first pressing piece (31) and the second pressing piece (32) are correspondingly provided with a second plane (35), and when the first pressing piece (31) and the second pressing piece (32) are matched with the seal (211), the first plane (212) and the second plane (35) are in contact with each other.

Images