A type of fixation rivet for avulsion fractures

Abstract

This invention discloses a fixation rivet for avulsion fractures, relating to the field of medical device technology. It includes a rivet body with a rivet end cap at its upper end. A hexagonal groove is formed at the center of the upper surface of the rivet end cap to facilitate drilling into the rivet body. A suture hole is formed on the side of the rivet end cap, and a suture hole is formed through the interior of the suture hole. A pressure plate is formed on the upper surface of the rivet end cap. This fixation rivet for avulsion fractures utilizes two sets of medical sutures interlaced with the suture holes. Based on the medical principles of stable suturing and precise positioning, it can reliably and accurately suture and position the pressure plate, effectively preventing positional displacement of the pressure plate due to external forces, tissue peristalsis, or other factors during surgical procedures or postoperative recovery. This ensures the pressure plate remains in the ideal fixed position, providing a solid guarantee for the stable fixation of the avulsed bone fragment or ligament, and significantly improving the accuracy and reliability of surgical treatment.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, specifically to a fixation rivet for avulsion fractures. Background Technology

[0002] Avulsion fractures are often caused by the forceful traction of ligaments or tendons, resulting in bone fragments being torn from the main bone. They are commonly found in the ankle joint (such as the insertion point of the anterior talofibular ligament) and the knee joint (such as the tibial insertion point of the posterior cruciate ligament). Such injuries are often accompanied by ligament rupture, requiring simultaneous repair of the bone-soft tissue connection. When avulsion fractures are accompanied by ligament damage, rivets are commonly used fixation devices. They achieve stable fixation by anchoring the ligament insertion point and distributing stress, and are especially suitable for complex injuries around the joint.

[0003] Prior art 1 (Chinese patent with announcement number CN208176571U, announcement date 2018-12-04) discloses a suture-supported anchor capable of stably connecting tendons and bones, comprising a anchor body, a groove, and a suture. The anchor body has a groove that is open at one end along its axial direction. The outer surface of the anchor body is threaded. One end of the suture is connected to the groove. Connecting one end of the suture to the groove of the anchor body ensures that one end is fixed during use, while the other end can be easily knotted with other sutures on the anchor body for secure fixation. The knot is small, ensuring the contact area between the tendon and bone, which is beneficial for postoperative healing. It provides a firm connection between tendons or bone fragments, enhancing the tendon-bone healing ability. It is particularly advantageous in the treatment of ligament insertion avulsion fractures. Reliable fixation can be achieved simply by screwing anchors around the bone bed or through the bone fragment, and the sutures between different anchors can be knotted together. Furthermore, it can prevent suture dislodgement due to improper operation during arthroscopic operation. It has great potential for widespread application in tendon-bone suture surgery.

[0004] Furthermore, prior art 2 (Chinese patent with announcement number CN206534671U, announcement date 2017-10-03) discloses a novel medical rivet, which includes: a rivet, a pressure plate, a locking screw, and a suture with a needle; the proximal end of the pressure plate is located at the tail end of the rivet, and the distal end of the pressure plate has a first screw hole; the rivet has a second screw hole; the locking screw passes through the first screw hole and the second screw hole, forming a stable "triangular frame" structure with the rivet and the pressure plate; the suture is connected to the pressure plate and is used to suture and reinforce the ligaments to which the avulsed bone fragments are attached, which can apply pressure to fix the avulsed bone fragments of the ligaments or tendons around the joint, promote fracture healing, and repair and reinforce ligaments or tendons, thereby facilitating early functional exercise of the affected limb after surgery and improving the function of the limb after injury.

[0005] Although current technology still requires suturing to position the compression plate when fixing it, the operation is relatively cumbersome. In addition, the use of rivets made of a single material results in slow bone growth and healing, and the use of rivets has certain limitations.

[0006] Therefore, we propose a fixation rivet for avulsion fractures to solve the problems mentioned above. Summary of the Invention

[0007] The purpose of this invention is to provide a fixation rivet for avulsion fractures, in order to solve the problems mentioned in the background art, where the current market requires suturing to position the compression piece, which is a rather cumbersome operation. At the same time, the use of rivets made of a single material results in slow bone growth and healing, and the use of rivets has certain limitations.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a fixation rivet for avulsion fractures, comprising a rivet body, a rivet end cap at the upper end of the rivet body, and a hexagonal groove at the center of the upper surface of the rivet end cap to facilitate auxiliary drilling of the rivet body; a threading hole at the side of the rivet end cap, with a threading hole penetrating through the interior of the threading hole; a pressure plate on the upper surface of the rivet end cap; an abutting mechanism between the rivet end cap and the interior of the rivet body, the abutting mechanism providing auxiliary limiting of the pressure plate through the movement of the fixation pin contained therein; and a limiting mechanism inside the rivet body, the limiting mechanism improving the stability of rivet body insertion through the movement of the auxiliary pin contained therein.

[0009] Preferably, the threading holes are arranged in a circular array of four groups about the center point of the rivet end cap, and the threading holes at the corresponding oblique angle positions are provided with the same sewing thread running through them. There are two groups of sewing threads, and the two groups of sewing threads are arranged alternately.

[0010] Preferably, the suture is laid through the pressure plate and knotted and tightened, and the pressure plate is located between the suture and the upper surface of the rivet end cap. The pressure plate can fix the ripped bone fragments and ligaments.

[0011] Preferably, the rivet body is made of metal, and the outer side of the rivet body is coated with a coating, which is an HA coating that promotes bone growth and healing.

[0012] Preferably, the abutting mechanism includes an abutting through hole, which is located at the center of the rivet end cap. The rivet body has an auxiliary cavity and a sliding groove inside, and the diameter of the auxiliary cavity is greater than the maximum value of the diameters of the abutting through hole and the sliding groove. The abutting through hole is connected to the auxiliary cavity through the sliding groove.

[0013] Preferably, a fixing pin is slidably connected to the rivet end cap, and the upper end of the fixing pin is tapered, while the inner side of the lower end of the fixing pin is inclined. At the same time, the lower end of the fixing pin is located at the auxiliary cavity position, and the fixing pins are arranged in a ring array about the center point of the rivet end cap.

[0014] Preferably, the sliding groove is slidably connected to an inner rod, and the upper end of the inner rod is fixedly connected to a flexible pad. The flexible pad is initially located at the hexagonal groove position and is located at the auxiliary cavity position when the flexible pad is adjusted. The fixing pin forms a sliding structure with the rivet end cap through the abutment action of the flexible pad. When the flexible pad is located below the fixing pin, the conical part of the fixing pin abuts against the lower surface of the pressure plate.

[0015] Preferably, the limiting mechanism includes a receiving groove, which is opened on the side of the rivet body and is arranged in a ring array about the center point of the rivet body. An auxiliary pin is slidably connected inside the receiving groove, and the outer end of the auxiliary pin is set in a conical structure, and the upper surface of the inner end of the auxiliary pin is set in an inclined structure.

[0016] Preferably, when the auxiliary nail is not in use, the tapered end is located inside the storage groove, and the inclined inner end of the auxiliary nail is located inside the sliding groove. The lower side of the inner rod is arranged in an arc shape, and when the inner rod is not in use, the lower end is located above the auxiliary nail. The auxiliary nail and the storage groove form a sliding structure through the inner rod.

[0017] Compared with the prior art, the beneficial effects of the present invention are:

[0018] (1) Four sets of threading holes are set, and two sets of medical sutures are interlaced and threaded through the holes. Based on the medical principle of stable suturing and precise positioning, reliable and precise suturing and positioning of the compression piece can be implemented. This effectively avoids the compression piece from shifting in position due to external force, tissue peristalsis and other factors during the operation or postoperative recovery. It ensures that the compression piece is always in the ideal fixed position, thus providing a solid guarantee for the stable fixation of avulsed bone fragments or ligaments, and significantly improving the accuracy and reliability of surgical treatment.

[0019] (2) The rivet body is made of metal material. Metal material has good biocompatibility and mechanical properties, which can provide a suitable micro-environment for bone growth. In addition, an HA coating is applied to the outside of the rivet body. Hydroxyapatite, as an inorganic component of human bone, has excellent osteoconductivity and osteoinductive properties. Through the synergistic effect of the HA coating and the metal rivet body, the local conditions for bone growth can be further optimized, the bonding strength between the rivet body and the surrounding bone tissue can be significantly enhanced, making the fixation more reliable, and thus effectively promoting the healing process of the fracture site.

[0020] (3) After the rivet body is inserted, downward pressure is applied to the flexible pad. The flexible pad moves downward under the pressure. Since the lower surface of the flexible pad is provided with an inner rod, the inner rod will slide down synchronously along the pre-set sliding groove as the flexible pad moves. During the process of the inner rod sliding down along the sliding groove, the auxiliary pin will move outward along the receiving groove according to the mechanical principle. As the auxiliary pin moves, the tapered part provided at its outer end will extend outward from the outside of the rivet body, so that the tapered part can interact with the surrounding tissue or structure in the lateral direction, thereby forming an effective limiting effect on the rivet body, significantly enhancing the stability of the rivet body at the implantation site, and ensuring that it can play a long-term and reliable fixing function.

[0021] (4) When the flexible pad is displaced to a specific position in the auxiliary cavity, the edge or contact surface of the flexible pad will make physical contact with the inclined part of the fixation pin, driving the fixation pin to move upward. After the flexible pad completes the contact and driving with the fixation pin, its own position is in the lower area of ​​the fixation pin, effectively preventing the fixation pin from returning downward under the influence of other external forces or its own weight, thereby ensuring the relative position stability of the fixation pin at the implantation site. At this time, the pressure plate is placed in the predetermined position and the pressure plate is fixed with sutures. The lower surface of the pressure plate is supported by the upward force of the fixation pin, and its upper surface is pulled downward by the sutures, forming a downward limiting mechanism. The double limiting mechanism of the upper and lower surfaces significantly enhances the stability of the pressure plate at the implantation site, enabling it to perform its predetermined function reliably and for a long time in the complex and ever-changing human physiological environment, meeting the needs of medical applications. Attached Figure Description

[0022] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0023] Figure 2 This is a three-dimensional structural diagram of the present invention in its assembled state;

[0024] Figure 3 This is a three-dimensional structural diagram of the rivet end cap of the present invention;

[0025] Figure 4 This is a three-dimensional cross-sectional view of the assembled structure of the present invention;

[0026] Figure 5 This is a schematic diagram of the three-dimensional cross-sectional structure of the present invention in its unassembled state;

[0027] Figure 6 This is a schematic diagram of the three-dimensional structure of the fixing nail of the present invention;

[0028] Figure 7 This is a schematic diagram of the three-dimensional structure of the flexible gasket of the present invention;

[0029] Figure 8 For the present invention Figure 5 Enlarged structural diagram at point A in the middle;

[0030] Figure 9 For the present invention Figure 5 Enlarged structural diagram at point B.

[0031] In the diagram: 1. Rivet body; 2. Rivet end cap; 3. Hexagonal groove; 4. Thread hole; 5. Pressure plate; 6. Coating; 7. Inner rod; 8. Flexible gasket; 9. Storage groove; 10. Sewing thread; 11. Auxiliary nail; 12. Fixing nail; 13. Sliding groove; 14. Abutment through hole; 15. Auxiliary cavity. Detailed Implementation

[0032] 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.

[0033] Example 1: To effectively promote the healing process of the fracture site, an HA hydroxyapatite coating 6 is applied to the outer side of the metal rivet body 1, thereby further promoting bone growth. Simultaneously, staggered sutures 10 are used to further improve the stability of the compression piece 5. Figure 1 - Figure 5 The present invention provides the following technical solution for fixing avulsion fractures: A rivet for fixing fractures is disclosed, wherein a rivet end cap 2 is provided at the upper end of the rivet body 1, and a hexagonal groove 3 is provided at the center of the upper surface of the rivet end cap 2 to facilitate auxiliary drilling of the rivet body 1; a threading hole 4 is provided on the side of the rivet end cap 2, and a threading hole 4 is provided through the interior of the threading hole 4; a pressure plate 5 is provided on the upper surface of the rivet end cap 2; and the threading holes 4 are arranged in a ring array about the center point of the rivet end cap 2. There are four sets of thread holes 4 at the corresponding oblique angles, and the same suture 10 is installed inside them. There are two sets of suture 10, and the two sets of suture 10 are arranged alternately. The suture 10 is installed through the pressure plate 5 and tied and tightened. The pressure plate 5 is located between the suture 10 and the upper surface of the rivet end cap 2. The ripped bone fragments and ligaments can be fixed by the pressure plate 5. The rivet body 1 is made of metal and the outer side of the rivet body 1 is coated with a coating 6. The coating 6 is an HA coating 6 that is conducive to bone growth and healing.

[0034] The device is equipped with four sets of threading holes 4, and two sets of sutures 10 are interlaced through the threading holes 4, enabling precise and reliable suturing and positioning of the compression piece 5. This effectively prevents the compression piece 5 from shifting during operation. Simultaneously, the interlaced layout of the sutures 10 further optimizes the positioning process of the compression piece 5, significantly improving operational efficiency and ensuring that the compression piece 5 can more firmly and accurately fix the avulsed bone fragments or ligaments. The rivet body 1 is made of metal, which possesses excellent biocompatibility and superior mechanical properties. Its biocompatibility ensures that it will not trigger a significant immune rejection reaction after implantation in the human body, providing a safe physiological environment for the adhesion, proliferation, and differentiation of bone cells on the rivet surface. Its excellent mechanical properties can withstand various stresses borne by the fracture site, maintaining the stability of the fracture ends, thereby creating a suitable environment for bone growth. The micromechanical environment is supported by an HA coating 6 on the outer side of the rivet body 1. Hydroxyapatite, as an inorganic component of human bone, has unique osteoconductivity and osteoinductive properties. Osteoconductivity allows bone cells to grow and extend along the surface of the HA coating 6, while osteoinductive properties can stimulate surrounding mesenchymal cells to differentiate into osteoblasts, promoting the formation of new bone. Through the synergistic effect of the HA coating 6 and the metal rivet body 1, the two complement each other and can further optimize the local conditions for bone growth. On the one hand, the HA coating 6 enhances the interaction between bone cells and the rivet; on the other hand, the metal rivet provides stable mechanical support. The combined effect of the two significantly enhances the bonding strength between the rivet body 1 and the surrounding bone tissue, making the fixation more reliable, thereby effectively promoting the healing process of the fracture site, shortening the rehabilitation time, and improving the treatment effect.

[0035] Example 2: To further improve the stability of the tablet press 5 and prevent its position from shifting, an abutting mechanism is provided. This mechanism double-limits the upper and lower surfaces of the tablet press 5, further ensuring its stability. Figure 4 - Figure 7 and Figure 9The present invention provides the following technical solution: a fixation rivet for avulsion fractures, wherein the rivet end cap 2 and the rivet body 1 are provided with an abutment mechanism. The abutment mechanism achieves auxiliary limiting of the pressure plate 5 by moving the fixation pin 12 contained therein. The abutment mechanism includes an abutment through hole 14, which is opened at the center of the rivet end cap 2. The rivet body 1 has an auxiliary cavity 15 and a sliding groove 13 inside, and the diameter of the auxiliary cavity 15 is greater than the maximum value of the diameter of the abutment through hole 14 and the sliding groove 13. The abutment through hole 14 is connected to the auxiliary cavity 15 through the sliding groove 13. The fixation pin 12 is slidably connected to the rivet end cap 2, and the fixation pin 12... The upper end of 2 is tapered, and the lower inner side of the fixing pin 12 is inclined. The lower end of the fixing pin 12 is located in the auxiliary cavity 15. The fixing pins 12 are arranged in a ring array about the center point of the rivet end cap 2. The inner rod 7 is slidably connected inside the sliding groove 13, and the upper end of the inner rod 7 is fixedly connected to the flexible pad 8. The flexible pad 8 is initially located in the hexagonal groove 3, and in the adjusted state, it is located in the auxiliary cavity 15. The fixing pin 12 forms a sliding structure with the rivet end cap 2 through the abutment of the flexible pad 8. When the flexible pad 8 is below the fixing pin 12, the tapered part of the fixing pin 12 abuts against the lower surface of the pressure plate 5.

[0036] During the downward movement of the flexible pad 8 under external pressure, it will first come into contact with and form an abutment with the contact hole 14. The diameter of the contact hole 14 is smaller than the initial size of the flexible pad 8. During the continuous downward movement, the flexible pad 8 will undergo corresponding elastic deformation based on the flexibility and deformation characteristics of the material, thereby overcoming the spatial constraints and continuing to move downward. When the flexible pad 8 moves to the position of the auxiliary cavity 15, since the space of the auxiliary cavity 15 is larger than the volume of the flexible pad 8, the flexible pad 8 will gradually unfold and return to its original shape after losing its constraint. The side of the unfolded flexible pad 8 will come into contact with the inclined part of the fixing nail 12 and generate an abutment force. According to the principles of mechanics, the resisting force will drive the fixing pin 12 to move upward gradually along its axis. After the flexible pad 8 is fully unfolded, its position is below the fixing pin 12, forming a mechanical limit on the downward movement of the fixing pin 12, preventing the fixing pin 12 from returning to its downward position. At this time, the pressure plate 5 will be placed, and the pressure plate 5 will be precisely limited by the suture 10 through the sewing operation. Under this structure, the pressure plate 5 is limited by the upward support of the fixing pin 12 on the lower surface and the downward pull of the suture 10 on the upper surface, forming a double limiting mechanism, which significantly improves the stability of the pressure plate 5 at the implantation site and ensures that it can function reliably and for a long time in the human physiological environment.

[0037] Example 3: To improve the stability of rivet body 1 insertion, a limiting mechanism is provided. This limiting mechanism creates a lateral force on the side of rivet body 1, enhancing the stability of rivet body 1 at the insertion site. Figure 4 , Figure 5 and Figure 8 The present invention provides the following technical solution: a fixation rivet for avulsion fractures, wherein the rivet body 1 is provided with a limiting mechanism inside. The limiting mechanism improves the stability of the rivet body 1 during insertion by moving the auxiliary nail 11 contained therein. The limiting mechanism includes a receiving groove 9, which is opened on the side of the rivet body 1 and is arranged in a ring array about the center point of the rivet body 1. The auxiliary nail 11 is slidably connected inside the receiving groove 9. The outer end of the auxiliary nail 11 is tapered and the upper surface of the inner end of the auxiliary nail 11 is inclined. When the auxiliary nail 11 is not in use, the tapered end is located inside the receiving groove 9 and the inclined part of the inner end of the auxiliary nail 11 is located inside the sliding groove 13. The lower side of the inner rod 7 is arc-shaped and the lower end of the inner rod 7 is above the auxiliary nail 11 when it is not in use. The auxiliary nail 11 forms a sliding structure with the receiving groove 9 through the inner rod 7.

[0038] During the insertion of the rivet body 1, the auxiliary pin 11 is placed inside the storage slot 9. This ensures that the auxiliary pin 11 will not obstruct the smooth insertion of the rivet body 1, guaranteeing the smoothness and accuracy of the insertion operation. After the rivet body 1 is inserted, a vertical downward pressure is applied to the flexible pad 8. Under this pressure, the flexible pad 8 will move downward in the vertical direction. Since the lower surface of the flexible pad 8 is fixedly provided with an inner rod 7, the inner rod 7 will slide downward along the pre-designed sliding groove 13 synchronously with the movement of the flexible pad 8. During the process of the inner rod 7 sliding down along the sliding groove 13, the inner rod 7 will... When the auxiliary pin 11 comes into contact with the inner rod 7, its upper surface is designed to be inclined. When it is subjected to the force of the inner rod 7, it will generate a component force along the receiving groove 9 outward according to the principle of inclined plane force in mechanics. This will drive the auxiliary pin 11 to move outward along the receiving groove 9. As the auxiliary pin 11 continues to move, the conical part of the auxiliary pin 11 will gradually extend outward to the external tissue environment of the rivet body 1. The auxiliary pin 11 interacts with the surrounding tissue and constructs a mechanical constraint mechanism on the rivet body 1 in the lateral dimension. This will significantly improve the biomechanical stability of the rivet body 1 at the implantation site and ensure its long-term reliable fixation in the human physiological environment.

[0039] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A fixing rivet for avulsion fractures, comprising a rivet body (1), wherein a rivet end cap (2) is provided at the upper end of the rivet body (1), and a hexagonal groove (3) is provided at the center of the upper surface of the rivet end cap (2) to facilitate auxiliary drilling into the rivet body (1), characterized in that, The rivet end cap (2) has a wire hole (4) on its side, and the wire hole (4) is provided inside the wire hole (4). The upper surface of the rivet end cap (2) is provided with a pressure plate (5). The rivet end cap (2) and the rivet body (1) are provided with an abutment mechanism. The abutment mechanism achieves auxiliary limiting of the pressure plate (5) by moving the fixing pin (12) contained therein. The rivet body (1) is also provided with a limiting mechanism. The limiting mechanism improves the stability of the rivet body (1) by moving the auxiliary pin (11) contained therein. The abutting mechanism includes an abutting through hole (14), which is located at the center of the rivet end cap (2). The rivet body (1) has an auxiliary cavity (15) and a sliding groove (13) inside. The diameter of the auxiliary cavity (15) is greater than the maximum diameter of the abutting through hole (14) and the sliding groove (13). The abutting through hole (14) is connected to the auxiliary cavity (15) through the sliding groove (13). A fixing pin (12) is slidably connected on the rivet end cap (2). The upper end of the fixing pin (12) is tapered, and the lower end of the fixing pin (12) is inclined. The lower end of the fixing pin (12) is located at the auxiliary cavity (15). The fixing pins (12) are arranged in a ring array about the center point of the rivet end cap (2).

2. The fixation rivet for avulsion fractures according to claim 1, characterized in that: The threading holes (4) are arranged in a circular array around the center point of the rivet end cap (2), and the same sewing thread (10) is provided inside the threading holes (4) at the corresponding oblique angle positions. There are two sets of sewing threads (10), and the two sets of sewing threads (10) are arranged alternately.

3. The fixation rivet for avulsion fractures according to claim 2, characterized in that: The suture (10) is laid through the pressure plate (5) and knotted and tightened. The pressure plate (5) is located between the suture (10) and the upper surface of the rivet end cap (2). The avulsed bone fragments and ligaments can be fixed by the pressure plate (5).

4. The fixation rivet for avulsion fractures according to claim 1, characterized in that: The rivet body (1) is made of metal, and the outer side of the rivet body (1) is coated with a coating (6), and the coating (6) is an HA coating (6) that is conducive to bone growth and healing.

5. A fixation rivet for avulsion fractures according to claim 4, characterized in that: The sliding groove (13) is slidably connected to an inner rod (7), and the upper end of the inner rod (7) is fixedly connected to a flexible pad (8). The flexible pad (8) is initially located at the position of the hexagonal groove (3), and in the adjusted state, it is located at the position of the auxiliary cavity (15). The fixing pin (12) forms a sliding structure with the rivet end cap (2) through the abutment action of the flexible pad (8). When the flexible pad (8) is located below the fixing pin (12), the conical part of the fixing pin (12) abuts against the lower surface of the pressure plate (5).

6. A fixation rivet for avulsion fractures according to claim 5, characterized in that: The limiting mechanism includes a storage groove (9), which is opened on the side of the rivet body (1). The storage groove (9) is arranged in a ring array about the center point of the rivet body (1). An auxiliary pin (11) is slidably connected inside the storage groove (9). The outer end of the auxiliary pin (11) is set in a conical structure, and the upper surface of the inner end of the auxiliary pin (11) is set in an inclined structure.

7. A fixation rivet for avulsion fractures according to claim 6, characterized in that: When the auxiliary pin (11) is not in use, the tapered end is located inside the storage groove (9), and the inclined inner end of the auxiliary pin (11) is located inside the sliding groove (13). The lower side of the inner rod (7) is arranged in an arc shape, and the lower end of the inner rod (7) is located above the auxiliary pin (11) when it is not in use. The auxiliary pin (11) forms a sliding structure with the storage groove (9) through the inner rod (7).

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