Ligament fixing system

Abstract

The invention relates to a ligament fixing system, which belongs to the technical field of orthopedic medical instruments, and comprises a screw main body, a screw rod, a screw rod and a screw rod, the fixing pin is arranged in the guide groove in a sliding fit manner; the surface of the fixing pin is provided with inverted teeth, and the maximum outer diameter of the inverted teeth in the radial direction of the screw body is larger than the diameter of the screw body. The axial guide groove is formed in the screw body, the fixing pin with the inverted teeth is implanted in the screw body, and due to the fact that the maximum outer diameter of the inverted teeth is larger than the diameter of the screw body, after the fixing pin is implanted into a bone tunnel, the inverted teeth can be embedded into a bone wall to generate strong frictional resistance and physical clamping; the resistance can directly counteract the reverse rotation torque borne by the screw, and the screw is effectively prevented from being reversely rotated and disengaged in the lead angle direction of the thread.

Description

Technical Field

[0001] This invention belongs to the field of orthopedic medical device technology, and in particular relates to a ligament fixation system. Background Technology

[0002] In ligament reconstruction surgery, ligament fixation screws are commonly used to secure ligaments within the bone tunnel. Traditional ligament fixation screws primarily use the threaded structure on their surface to compress and fix the ligament.

[0003] However, existing ligament fixation screws typically rely solely on their threaded structure for fixation. During postoperative rehabilitation and daily activities, the screws are subjected to continuous tensile and torsional stresses from the ligament. Due to the helix angle of the threaded structure, the screw is prone to counter-rotation along the direction of the helix angle, leading to loosening or dislodgement. Furthermore, relying solely on thread compression often results in insufficient initial fixation strength in cases of osteoporosis.

[0004] Based on this, a ligament fixation system is proposed in this publication. Summary of the Invention

[0005] The purpose of this invention is to provide a ligament fixation system that improves the fixation strength of screws within the bone tunnel.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] A ligament fixation system includes: fixation screws and implantation tools;

[0008] The fixing screw includes a screw body and a fixing pin;

[0009] The screw body has an axially extending guide groove on its outer peripheral surface;

[0010] A fixing pin, which fits into the guide groove, and the fixing pin has a tapping guide groove in the axial direction;

[0011] The surface of the retaining pin is provided with reverse teeth, and the maximum outer diameter of the reverse teeth in the radial direction of the screw body is greater than the diameter of the screw body;

[0012] The implantation tool includes a knock-in core, the lower end of which is provided with an abutment mounting head, and the lower end of the abutment mounting head is provided with at least one insert tooth.

[0013] Beneficial effects:

[0014] This disclosure involves setting an axial guide groove on the screw body and inserting a fixing pin with reverse teeth. Since the maximum outer diameter of the reverse teeth is larger than the diameter of the screw body, after the fixing pin is inserted into the bone tunnel, the reverse teeth will embed into the bone wall to generate strong frictional resistance and physical locking. Since the fixing pin is restricted in the guide groove, this resistance can directly offset the counter-rotation torque on the screw, effectively preventing the screw from rotating out in the reverse direction of the thread helix angle.

[0015] This disclosure provides not only resistance to reverse rotation force through the reverse tooth structure of the fixing pin, but also increases the radial compressive stress of the screw as a whole within the bone tunnel. Especially in patients with osteoporosis, the insufficient thread fixation force can be compensated by increasing the implantation of the pin.

[0016] This disclosure provides a tapping tooth with chamfered sides at the front end of the fixation pin. During the tapping process, the tapping tooth can smoothly guide the ligament at the guide groove to separate outwards, avoiding direct severing of the ligament fibers by the edge of the fixation pin, which is beneficial for postoperative tendon and bone healing.

[0017] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the ligament fixation screw in an embodiment of this disclosure;

[0020] Figure 2 This is a schematic diagram of the screw body in an embodiment of this disclosure;

[0021] Figure 3 This is a schematic diagram showing the distribution of the fixed pin guide grooves in an embodiment of this disclosure;

[0022] Figure 4 This is a schematic diagram of the structure of the fixing pin in an embodiment of this disclosure;

[0023] Figure 5 This is a schematic diagram of the fixed pin reciprocating tooth structure in an embodiment of this disclosure;

[0024] Figure 6 This is a schematic diagram of the knock-in guide groove structure of the fixing pin in an embodiment of this disclosure;

[0025] Figure 7 This is a schematic diagram of the two-pin fixing pin structure disclosed in this paper;

[0026] Figure 8 This is a schematic diagram of the single-pin fixing pin structure disclosed in this paper;

[0027] Figure 9 This is a schematic diagram of the implantation tool structure disclosed herein;

[0028] Figure 10 This is a diagram illustrating the effect of using the implantation tool disclosed herein;

[0029] Figure 11 The results are shown for the currently mainstream ligament fixation screws;

[0030] Figure 12 This is a schematic diagram of the striking block structure in an embodiment of this disclosure;

[0031] Figure 13 This is a schematic diagram of the outer protective sleeve structure in an embodiment of this disclosure;

[0032] Figure 14 This is a schematic diagram of the internal structure of the implantation tool in an embodiment of this disclosure;

[0033] Figure 15 This is a schematic diagram of the striking head structure in an embodiment of this disclosure;

[0034] Figure 16 This is a schematic diagram of the internal structure of the knock-in device in an embodiment of this disclosure;

[0035] Figure 17 This is a cross-sectional view of the implantation tool in an embodiment of this disclosure. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] This embodiment discloses a ligament fixation system, including fixation screws and an implantation tool 3;

[0038] The fixing screw includes a screw body 1 and a fixing pin 2.

[0039] The screw body 1 is provided with an axially extending guide groove 1.1, and the fixing pin 2 is provided with a hammer-in guide groove 2.2 in the axial direction;

[0040] The fixing pin 2 slides within the guide groove 1.1, and its surface is provided with reverse teeth 2.1. The maximum outer diameter of the reverse teeth 2.1 is larger than the diameter of the screw body 1. With this design, when the fixing pin 2 enters the bone channel, the reverse teeth 2.1 will embed into the bone wall, avoiding obstruction of the screw 1 from reversing along the thread helix angle direction.

[0041] like Figure 12 As shown, the implantation tool 3 includes an indenter core 3.4, and the lower end of the indenter core is provided with an abutment mounting head 3.4.0. The lower end of the abutment mounting head 3.4.0 is provided with at least one inserting tooth 3.4.1. With this design, the lower end of the abutment mounting head 3.4.0 applies pressure to the fixing pin 2 to fix the pin 2. During installation, the inserting tooth 3.4.1 can be inserted into the indenter guide groove 2.2 to prevent the indenter from bending during the indentation process.

[0042] In some disclosures, the abutment mounting head 3.4.0 is composed of at least one triangular abutment plate, which is fixedly disposed at the lower end of the inner core 3.4 of the knocker.

[0043] like Figures 9-17 As shown, the accompanying implantation tool 3 also includes an outer protective sleeve 3.3;

[0044] The inner core 3.4 is located inside the outer protective sleeve 3.3, and the upper end of the outer protective sleeve 3.3 is provided with a striking block 3.1;

[0045] The striking block 3.1 has a mounting groove at its lower end for mounting the outer protective sleeve 3.3, and striking sliders 3.1.2 are provided on both sides of the mounting groove;

[0046] The outer protective sleeve 3.3 is installed in the mounting groove at the lower end of the striking block 3.1. The outer protective sleeve 3.3 has a slider groove 3.3.1 on its side that cooperates with the striking block 3.1. During installation, the striking block 3.1 is installed in the slider groove 3.3.1. The outer protective sleeve 3.3 has a through hole in the center for installing the inner core 3.4. The through hole has movable slide rails 3.3.2 on both sides.

[0047] The inner core 3.4 has slide rail grooves 3.4.2 on both sides of its upper end, which cooperate with the movable slide rail 3.3.2; the inner core 3.4 has bolt holes 3.4.3 on its end face, and a striking head 3.2.2 is installed in the bolt holes 3.4.3. The striking head 3.2.2 is installed by a threaded rod 3.2.1 at its lower end that cooperates with the bolt holes 3.4.3.

[0048] During installation, 3.1.2 tap the slider into the slider groove of 3.3.1. When the tapping block 3.1 is tapped, the outer protective sleeve 3.3 moves downward, and the moving slide rail 3.3.2 is installed into the slide rail groove 3.4.2. When the outer protective sleeve 3.3 moves downward, it drives the inner core 3.4 of the tapper to move. The insert tooth 3.4.1 cooperates with the tapping guide groove 2.2, so that the fixing pin 2 moves along the fixing pin guide groove 1.1, and the installation is completed.

[0049] like Figure 4 As shown, in some disclosures, the end face of the fixing pin 2 is provided with a guide positioning hole 2.3;

[0050] The inner core 3.4 has a positioning pin 3.2 at its front end. The positioning pin 3.2 is set in the guide positioning hole 2.3 so that the fixing pin 2 forms a rigid connection with the tool 3 before implantation.

[0051] During implantation, the impact force is transmitted to the inner core 3.4 by applying an impact to the striking block 3.1. The inner core 3.4 drives the fixing pin 2 to slide in along the guide groove 1.1 and finally settle in the fixing groove 1.2.

[0052] like Figure 6 As shown, in some embodiments, the front end of the fixing pin 2 is provided with a tapping tooth 2.5, and the front ends of the tapping tooth 2.5 are chamfered. During the tapping process, the tapping tooth 2.5 can separate the ligament located at the guide groove outward, avoiding the fixing pin from directly cutting the ligament, and at the same time making the ligament fit more tightly to the bone wall to facilitate recovery.

[0053] like Figure 3 As shown, in some embodiments, the screw body 1 is provided with four axially extending guide grooves 1.1, the screw head is provided with four symmetrically distributed fixing grooves 1.2, and the fixing pin 2 is provided with four corresponding pin bodies.

[0054] Furthermore, the number of guide grooves 1.1 on the screw body 1 can be designed to adapt to the patient's bone condition and the required tightening force, such as... Figures 7-8 As shown, the pin body of fixing pin 2 can be set to one or two.

[0055] It should be understood that the number of guide grooves 1.1 provided on the screw body 1 is not limited to the number recorded in this specification. Those skilled in the art can choose and set them reasonably as needed. It should also be noted that the number of pins of the fixing pin 2 provided in this disclosure can be less than the number of guide grooves 1.1 provided on the screw body 1. With this design, pins can be selectively inserted according to the surgical procedure for patients with severe osteoporosis.

[0056] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0057] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A ligament fixation system, characterized in that, Includes: fixing screws and implantation tools; The fixing screw includes a screw body and a fixing pin; The screw body has an axially extending guide groove on its outer peripheral surface; A fixing pin, which fits into the guide groove, and the fixing pin has a tapping guide groove in the axial direction; The surface of the retaining pin is provided with reverse teeth, and the maximum outer diameter of the reverse teeth in the radial direction of the screw body is greater than the diameter of the screw body; The implantation tool includes a knock-in core, the lower end of which is provided with an abutment mounting head, and the lower end of the abutment mounting head is provided with at least one insert tooth.

2. The ligament fixation system according to claim 1, characterized in that, The implantation tool also includes an outer protective sleeve, the inner core is located inside the outer protective sleeve, and a striking block is provided at the upper end of the outer protective sleeve; The striking block has a mounting groove at its lower end for installing an outer protective sleeve, and striking sliders are provided on both sides of the mounting groove; The outer protective sleeve is set in the mounting groove at the lower end of the striking block. The side of the outer protective sleeve is provided with a slider groove that cooperates with the striking block. The center of the outer protective sleeve is provided with a through hole for installing the inner core. The two sides of the through hole are provided with movable slide rails. The inner core has slide rail grooves on both sides of its upper end that cooperate with the movable slide rail; the end face of the inner core has bolt holes, and a striking head is installed in the bolt holes. The striking head is installed by a threaded rod at its lower end that cooperates with the bolt holes.

3. The ligament fixation system according to claim 1, characterized in that, The end face of the screw body is provided with a fixing groove that communicates with the guide groove, and the tail end of the fixing pin is adapted to the fixing groove.

4. The ligament fixation system according to claim 1, characterized in that, The front end of the fixing pin is provided with a hammering tooth, and the front ends of the hammering tooth are chamfered on both sides.

5. A ligament fixation system according to claim 1, characterized in that, The end face of the fixing pin is provided with a guide positioning hole.

6. A ligament fixation system according to claim 1, characterized in that, The end face of the fixing pin is also provided with a striking groove.

7. A ligament fixation system according to claim 1, characterized in that, The number of guide grooves is multiple, and the fixing pin includes multiple pin bodies that are respectively adapted to the guide grooves; The number of teeth on the implantation tool corresponds to the number of pins on the fixing pin.

8. A ligament fixation system according to claim 7, characterized in that, The number of guide grooves is four, and the four guide grooves are evenly distributed along the circumference of the screw body.

9. A ligament fixation system according to claim 7, characterized in that, The number of pins in the fixed pin is less than the number of guide grooves.

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