Combined interface screws

Abstract

This invention relates to a combined interface screw, comprising a screw body and a fixing member. The screw body has an axial through hole and a radial through hole. The axial through hole extends axially through the proximal end face of the screw body, and the radial through hole extends radially through the side wall of the axial through hole, communicating with the axial through hole. The fixing member includes an elastic part and a retaining tooth part connected together. When the fixing member moves along the axial through hole to the point where the retaining tooth part is opposite to the radial through hole, the elastic part drives the retaining tooth part to extend out of the radial through hole. In this combined interface screw, after the screw body is screwed into the bone tunnel, the fixing member can be moved along the axial through hole to the point where the retaining tooth part is opposite to the radial through hole. This causes the elastic part to drive the retaining tooth part to extend out of the radial through hole, thus embedding the retaining tooth part into the side wall of the bone marrow tract. This increases the resistance to the screw body's back-and-forth movement and rotation within the bone marrow tract, thereby preventing the screw body from moving out of the bone marrow tract and improving the fixation effect.

Description

Technical Field

[0001] This invention relates to the field of orthopedic medical devices, and in particular to a combined interface screw. Background Technology

[0002] When the anterior and posterior cruciate ligaments of the human knee joint are damaged, the damaged ligaments need to be reconstructed and fixed. Currently, clinicians commonly use combination interface screws to fix the ligaments in the bone tunnel by compression.

[0003] However, because the ligaments of the human knee joint bear strong forces during exercise, the interface screws are prone to dislodgement during the postoperative recovery process, losing their fixation function and adversely affecting the patient's normal recovery and the smooth implementation of related medical measures. Summary of the Invention

[0004] Based on this, a combined interface screw is provided to solve the problem of how to prevent the interface screw from moving out.

[0005] This invention provides a combined interface screw, comprising:

[0006] The screw body has an axial through hole and a radial through hole. The axial through hole extends through the near end face of the screw body along the axial direction of the screw body, and the radial through hole extends through the side wall of the axial through hole along the radial direction of the screw body, so as to communicate with the axial through hole.

[0007] The fastener includes an elastic portion and a locking tooth portion connected together. When the fastener moves along the axial through hole to such that the locking tooth portion is opposite to the radial through hole, the elastic portion drives the locking tooth portion to extend out of the radial through hole.

[0008] In one embodiment, when the retaining tooth extends from the radial through hole, the ratio of the height of the retaining tooth protruding from the screw body to the height of the screw thread is in the range of 1:2 to 5:1.

[0009] In one embodiment, the locking tooth has a limiting surface and a tip connected to the limiting surface. When the combined interface screw is implanted into the bone marrow tract, the tip is used to anchor to the sidewall of the bone marrow tract so that the limiting surface restricts the locking tooth from moving out of the bone marrow tract.

[0010] In one embodiment, the retaining tooth has a guide arc surface disposed opposite to the limiting surface, and the tip is formed at the connection between the limiting surface and the guide arc surface. The guide arc surface is used to guide the fixing member into the axial through hole.

[0011] In one embodiment, the elastic part is U-shaped, and both ends of the elastic part are provided with the retaining teeth. The screw body is provided with two radial through holes, and the two radial through holes correspond to the two retaining teeth respectively.

[0012] In one embodiment, the screw body includes a screw head section, a screw middle section, and a screw tail section connected sequentially along its axial direction, and at least one of the screw head section, the screw middle section, and the screw tail section is provided with the radial through hole.

[0013] In one embodiment, at least one location along the axial direction of the screw body is provided with a plurality of radial through holes;

[0014] And / or, the screw body is provided with a plurality of radial through holes arranged along the axial direction of the screw body.

[0015] In one embodiment, the sidewall of the axial through hole is provided with a guide groove, the guide groove is connected to the radial through hole, and the guide groove is used to guide the locking tooth part to move in the axial through hole to be opposite to the radial through hole;

[0016] Alternatively, the axial through hole has a first groove wall and a second groove wall disposed opposite to each other, and the gap between the first groove wall and the second groove wall is used to guide the retaining tooth portion to move opposite to the radial through hole.

[0017] In one embodiment, a limiting wall is formed inside the screw body, the limiting wall being located on the side of the radial through hole away from the proximal end face of the screw body. When the fastener moves along the axial through hole to abut against the limiting wall, the limiting wall guides the retaining tooth portion to move radially and extend out of the radial through hole.

[0018] In one embodiment, the distal end of the screw body includes a tapered body with a through hole. The through hole extends through the tapered body along the axial direction of the screw body and communicates with the axial through hole. The diameter of the axial through hole is larger than the diameter of the through hole.

[0019] In one embodiment, the axial through hole forms a drive interface on the proximal end face of the screw body, and the cross-sectional shape of the drive interface is cross-shaped, regular polygonal, or quincunx-shaped.

[0020] The aforementioned combined interface screw includes a screw body and a fixing member. The screw body has an axial through hole and a radial through hole. After the screw body is screwed into the bone tunnel, the fixing member can be moved along the axial through hole so that the retaining teeth are opposite to the radial through hole. The elastic part drives the retaining teeth to extend out of the radial through hole, so that the retaining teeth will be embedded in the side wall of the bone marrow tract. This increases the resistance of the screw body to the back-and-forth movement and rotation in the bone marrow tract, thereby preventing the screw body from moving out of the bone marrow tract and improving the fixation effect. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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 embodiments can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the combined interface screw of the present invention;

[0023] Figure 2 for Figure 1 A schematic diagram of the cross-sectional structure of the combined interface screw is shown.

[0024] Figure 3 for Figure 1 The diagram shows a cross-sectional view of the screw body of the combined interface screw along another section.

[0025] Figure 4 A schematic diagram of the structure of the fastener in a combined interface screw according to one embodiment, wherein the elastic part of the fastener is in a compressed state;

[0026] Figure 5 A schematic diagram of the structure of the fastener in a combined interface screw according to one embodiment, wherein the elastic part of the fastener is in an expanded state;

[0027] Figure 6 This is a cross-sectional structural schematic diagram of a combined interface screw according to another embodiment of the present invention.

[0028] Figure 7 for Figure 6 The diagram shows a combined interface screw with the retaining teeth protruding from the radial through hole.

[0029] Figure 8 This is a schematic diagram of the structure of a combined interface screw according to another embodiment of the present invention;

[0030] Figure 9 This is a schematic diagram of the structure of a combined interface screw according to another embodiment of the present invention;

[0031] Figure 10 This is a schematic diagram of another embodiment of the combined interface screw of the present invention.

[0032] Reference numerals: 10, screw body; 11, axial through hole; 12, radial through hole; 10a, drive interface; 10b, tapered body; 10c, through hole; 13, thread; 10d, guide groove; A, screw head section; B, screw middle section; C, screw tail section; 20, fastener; 21, elastic part; 22, retaining tooth part; 22a, limiting surface; 22b, tip; 22c, guide arc surface. Detailed Implementation

[0033] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0034] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0035] It should be noted that when a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0036] Combination Figure 1 and Figure 2As shown, the present invention provides a combined interface screw, including a screw body 10 and a fixing member 20. The screw body 10 can be a flat-head screw, a round-head screw, or a countersunk screw, and is not limited thereto. The screw body 10 has an axial through hole 11 and a radial through hole 12. The axial through hole 11 penetrates the near-end face of the screw body 10 (i.e., the end face of the screw body 10 that connects to a screwdriver or other tool) along the axial direction of the screw body 10. The radial through hole 12 penetrates the sidewall of the axial through hole 11 along the radial direction of the screw body 10, and communicates with the axial through hole 11. It should be noted that the sidewall of the axial through hole 11 refers to the portion of the screw body 10 that encloses and forms the axial through hole 11 and has a certain wall thickness. The fixing member 20 includes an elastic part 21 and a retaining tooth part 22 connected together. When the fixing member 20 moves along the axial through hole 11 so that the retaining tooth part 22 is opposite to the radial through hole 12, the elastic part 21 drives the retaining tooth part 22 to extend out of the radial through hole 12.

[0037] In the aforementioned combined interface screw, after the screw body 10 is screwed into the bone tunnel, the fixing member 20 can be moved along the axial through hole 11 so that the locking tooth 22 is opposite to the radial through hole 12. Thus, the elastic part 21 drives the locking tooth 22 to extend out of the radial through hole 12, so that the locking tooth 22 will be embedded in the side wall of the bone marrow tract, increasing the resistance of the screw body 10 to the back-and-forth movement and rotation in the bone marrow tract, thereby preventing the screw body 10 from moving out of the bone marrow tract and improving the fixation effect.

[0038] It should be noted that the proximal end face of the screw body 10 is provided with a drive interface 10a, which is used to cooperate with tools such as screwdrivers and electric screwdrivers so that the screw body 10 can be rotated using the tools so that the screw body 10 can be implanted into the bone marrow tract.

[0039] In some embodiments, the axial through hole 11 forms a drive interface 10a on the near end face of the screw body 10. The cross-sectional shape of the drive interface 10a is cross-shaped, regular polygonal, or quincunx-shaped, and is not limited here. The drive interface 10a can be pyramidal, that is, the sidewall of the drive interface 10a has a certain taper, which can play a guiding role and facilitate the quick engagement of tools such as screwdrivers and electric screwdrivers with the drive interface 10a.

[0040] It should be noted that in the embodiment where the axial through hole 11 forms a drive interface 10a on the proximal end face of the screw body 10, the fastener 20 can enter the axial through hole 11 from the drive interface 10a and eventually move along the drive interface 10a to a position where the locking tooth 22 is opposite to the radial through hole 12, so that the locking tooth 22 extends out from the radial through hole 12 and is embedded in the side wall of the bone marrow tract.

[0041] See Figure 2As shown, when the retaining tooth 22 extends from the radial through hole 12, the ratio of the height of the retaining tooth 22 protruding from the screw body 10 to the height of the thread 13 of the screw body 10 ranges from 1:2 to 5:1. For example, the former (the height of the retaining tooth 22 protruding from the screw body 10) is half the height of the latter (the height of the thread 13), or the former is equal to the latter, or the former is 2, 3, 4, or 5 times the height of the latter. With this setting, the height of the retaining tooth 22 protruding from the screw body 10 is neither too large nor too small. If the height of the retaining tooth 22 protruding from the screw body 10 is too high, it may damage the bone because the retaining tooth 22 inserts too deeply into the side wall of the medullary tract. If the height of the retaining tooth 22 protruding from the screw body 10 is too low, the fixation effect on the screw body 10 will be insignificant because the retaining tooth 22 inserts too shallowly into the side wall of the medullary tract.

[0042] In some implementations, see Figure 2 As shown, the distal end of the screw body 10 includes a tapered body 10b, with a perforation 10c. The perforation 10c penetrates the tapered body 10b along the axial direction of the screw body 10 and communicates with an axial through-hole 11. This allows bone debris to enter the axial through-hole 11 through the perforation 10c when the combined interface screw is implanted into the medullary tract, reducing the amount of bone debris between the combined interface screw and the inner wall of the medullary tract, and minimizing compression of the medullary tract during implantation. The diameter of the axial through-hole 11 is larger than the diameter of the perforation 10c to ensure the structural strength of the tapered body 10b at the distal end of the screw body 10.

[0043] Combining 2 and Figure 3 As shown, a guide groove 10d is provided on the side wall of the axial through hole 11. The guide groove 10d is connected to the radial through hole 12. The guide groove 10d is used to guide the retaining tooth part 22 to move within the axial through hole 11 to be opposite to the radial through hole 12. Since the guide groove 10d can provide a good guiding effect for the retaining tooth part 22, when it is necessary to use the fastener 20 to enhance the fixation stability of the screw body 10 in the medullary tract, the guide groove 10d can be used to quickly guide the retaining tooth part 22 to the position opposite to the radial through hole 12, thereby improving the operating efficiency.

[0044] Furthermore, the guide groove 10d extends along the axial direction of the screw body 10. Based on the guiding effect of the guide groove 10d on the locking tooth 22, the guide groove 10d can also restrict the locking tooth 22 from rotating relative to the screw body 10 in the axial direction of the screw body 10, so that the locking tooth 22 moves smoothly relative to the screw body 10.

[0045] Combination Figure 4 and Figure 5 As shown, where, Figure 4 This shows that the elastic part 21 of the fastener 20 is in a compressed state. Figure 5 The elastic portion 21 recovers its deformation, causing the retaining tooth portion 22 to open outward. Specifically, the retaining tooth portion 22 has a limiting surface 22a and a tip 22b connected to the limiting surface 22a. When the combined interface screw is implanted into the bone marrow tract, the tip 22b is used to anchor to the side wall of the bone marrow tract, so that the limiting surface 22a restricts the retaining tooth portion 22 from moving out of the bone marrow tract. In this embodiment, the tip 22b of the retaining tooth portion 22 can be easily inserted into the side wall of the bone marrow tract so that the limiting surface 22a can play a good limiting role and prevent the screw body 10, which is limited by the retaining tooth portion 22, from moving out of the bone marrow tract.

[0046] Furthermore, the locking tooth 22 has a guide arc surface 22c that is disposed opposite to the limiting surface 22a. A tip 22b is formed at the connection between the limiting surface 22a and the guide arc surface 22c. The guide arc surface 22c is used to guide the fixing member 20 into the axial through hole 11, making it easier to insert the fixing member 20 into the axial through hole 11.

[0047] Continue reading Figure 4 and Figure 5 As shown, in some embodiments, the elastic portion 21 is U-shaped, and both ends of the elastic portion 21 are provided with retaining teeth 22. It can be understood that, as... Figure 2 As shown, the screw body 10 is provided with two radial through holes 12, which correspond to two locking teeth 22 respectively. With this structure, the U-shaped elastic part 21 can exert an elastic driving effect on the two locking teeth 22, so that the two locking teeth 22 extend from opposite sides of the screw body 10 and insert into the side wall of the bone marrow tract to strengthen the anchoring force on the screw body 10.

[0048] It should be noted that the fixation member 20 can be pre-loaded in the axial through hole 11, or it can be inserted into the axial through hole 11 after the screw body 10 is implanted and moved along the axial through hole 11 so that the retaining tooth 22 protrudes from the radial through hole 12. In this way, the retaining tooth 22 is inserted into the side wall of the bone marrow tract, thereby improving the stable anchoring force and strengthening the stability of the screw body 10 in the bone marrow tract so that it is not easy to move out.

[0049] For example, in some embodiments, before the screw body 10 is implanted into the bone marrow tract, the fixing member 20 is not placed in the axial through hole 11 of the screw body 10. First, the drive interface 10a of the screw body 10 is connected using a screwdriver, electric screwdriver, or other tools, and the screw body 10 is screwed into the bone tunnel. After screwing to the predetermined position, the tools are removed, and then the fixing member 20 is squeezed to compress the elastic part 21, thereby facilitating the insertion of the fixing member 20 from the proximal end face of the screw body 10 into the axial through hole 11. Then, the retaining teeth 22 of the fixing member 20 are moved along the guide groove 10d to be opposite to the radial through hole 12. In this way, the retaining teeth 22 can extend from the radial through hole 12 and embed into the side wall of the bone marrow tract under the elastic force of the elastic part 21, thereby achieving an anchoring effect, strengthening the fixation of the screw body 10, and preventing the screw body 10 from moving out of the bone marrow tract.

[0050] For example, combining Figure 6 As shown, before the screw body 10 is implanted into the bone marrow tract, the fixation member 20 is pre-placed into the axial through hole 11 along the guide groove 10d. After connecting the drive interface 10a of the screw body 10 using tools such as screwdrivers or electric screwdrivers, and screwing the screw into the bone tunnel, a rod-shaped instrument can be inserted into the axial through hole 11 through the drive interface 10a and pushed towards the side where the radial through hole 12 is located. This ultimately causes the retaining teeth 22 of the fixation member 20 to move along the guide groove 10d to be opposite to the radial through hole 12, so that the elastic part 21 recovers its deformation and drives the retaining teeth 22 to protrude from the radial through hole 12 out of the screw body 10 (see...). Figure 7 As shown, the screw body 10 is anchored to the bone marrow tract by using the toothed part 22 to embed into the side wall of the bone marrow tract, so that the screw body 10 is not easy to move out of the bone marrow tract.

[0051] It should be noted that the elastic part 21 can also be other shapes, such as V-shaped or W-shaped, or other irregular shapes, as long as it can provide elastic force for the retaining tooth part 22 to move radially relative to the screw body 10.

[0052] The shape of the axial through hole 11 is not limited in this embodiment. As long as the fastener 20 can be moved from the proximal end face of the screw body 10 to the point where the retaining teeth 22 are opposite to the radial through hole 12, the retaining teeth 22 can extend out of the radial through hole 12 to engage with the side wall of the bone marrow tract, thereby improving the anchoring force between the screw body 10 and the bone marrow tract. For example, in some embodiments, the cross-sectional shape of the axial through hole 11 is cross-shaped, triangular, quadrilateral, pentagonal, or hexagonal, and is not limited here.

[0053] Furthermore, in some embodiments, the sidewall of the axial through hole 11 can itself be used to guide the movement of the retaining tooth 22. That is, in this case, it is not necessary to form a guide groove 10d in the sidewall of the axial through hole 11. Specifically, the axial through hole 11 has a first groove wall and a second groove wall disposed opposite to each other. The gap between the first groove wall and the second groove wall is used to guide the retaining tooth 22 to move within the axial through hole 11 to be opposite to the radial through hole 12. In this embodiment, when the fastener 20 is generally elongated, the cross-section of the axial through hole 11 can be an elongated shape adapted to the shape of the fastener 20, thereby using the first groove wall and the second groove wall of the axial through hole 11 to guide the fastener 20.

[0054] It should be noted that the orthographic projection shape of the fastener 20 on the plane near the end face of the screw body 10 along the axial direction of the screw body 10 can also be a rectangle, square, ellipse, or other shapes. In this case, as long as the cross-sectional shape of the axial through hole 11 corresponds to the orthographic projection shape, the groove wall of the axial through hole 11 can guide the retaining tooth 22 to move within the axial through hole 11 to be opposite to the radial through hole 12. The cross-sectional shape of the axial through hole 11 and the orthographic projection shape of the fastener 20 on the plane near the end face of the screw body 10 along the axial direction of the screw body 10 will not be described in detail here.

[0055] In some embodiments, a limiting wall 121 is formed inside the screw body 10. Specifically, the limiting wall 121 is located on the side of the radial through hole 12 away from the proximal end face of the screw body 10. When the fastener 20 moves along the axial through hole 11 to abut against the limiting wall 121, the fastener 20 will not be able to continue moving towards the side away from the proximal end face of the screw body 10 due to the limiting wall 121. Finally, the limiting wall 121 guides the retaining tooth portion 22 to move radially so that the retaining tooth portion 22 protrudes from the radial through hole 12.

[0056] It should be noted that the limiting wall 121 can be formed by extending part of the sidewall of the radial through hole 12, or it can be formed by the groove wall of the axial through hole 11 near the end face away from the screw body 10. In other embodiments, the axial through hole 11 can form a stepped groove at the position corresponding to the radial through hole 12, thereby forming the limiting wall 121 at the position where the radial dimension of the stepped groove changes. The formation method of the limiting wall 121 is not limited here, as long as the fixing member 20 can move along the axial through hole 11 to abut against the limiting wall 121, so that the limiting wall 121 can restrict the fixing member 20 from continuing to move in the direction away from the end face of the screw body 10, so as to guide the retaining tooth 22 to extend out of the radial through hole 12. That is, when the retaining tooth 22 moves to abut against the limiting wall 121, the retaining tooth 22 is axially limited in the limiting wall 121. As the elastic part 21 recovers its deformation, the retaining tooth 22 moves along the limiting wall 121 and extends out of the radial through hole 12.

[0057] The shape of the elastic part 21 and the number of the retaining teeth 22 are not limited here. Figure 3 As shown, in some embodiments, the screw body 10 includes a screw head section A, a screw middle section B, and a screw tail section C connected sequentially along its axial direction. At least one of the screw head section A, screw middle section B, and screw tail section C is provided with a radial through hole 12. Specifically, the radial through hole 12 can be formed in the screw head section A, the screw middle section B, or the screw tail section C. Alternatively, the screw head section A, the screw middle section B, and the screw tail section C can all be provided with radial through holes 12. Multiple retaining teeth 22 extend sequentially from the corresponding radial through holes 12, and the anchoring force between the multiple retaining teeth 22 and the sidewall of the bone marrow tract enhances the stability of the screw body 10 within the bone marrow tract.

[0058] In some embodiments, at least one location on the axial side of the screw body 10 is provided with a plurality of radial through holes 12. Figure 8 As shown, two radial through holes 12 are provided at two positions along the axial direction of the screw body 10. This allows for the arrangement of a corresponding number of retaining teeth 22 at these two axial positions, enhancing the connection stability between the screw body 10 and the bone marrow tract. For example, in an embodiment where the fixing member 20 includes two retaining teeth 22, the two retaining teeth 22 extend from the corresponding two radial through holes 12. It is understood that multiple retaining teeth 22 can be connected by an elastic part 21. For example, one elastic part 21 can be connected to four retaining teeth 22, with the four retaining teeth 22 positioned opposite each other at different axial positions of the screw body 10. This utilizes the anchoring force between the four retaining teeth 22 and the sidewall of the bone marrow tract to enhance the stability of the screw body 10, making it less likely for the screw body 10 to dislodge from the bone marrow tract.

[0059] In some embodiments, the screw body 10 is provided with a plurality of radially arranged through holes 12 along the axial direction of the screw body 10, so that corresponding retaining teeth 22 can pass through these radially arranged through holes 12. The more retaining teeth 22 are anchored to the sidewalls of the bone marrow tract, the greater the stability of the screw body 10 within the bone marrow tract, and consequently the less likely it is to be dislodged from the bone marrow tract. For example, combined with Figure 9 As shown, four radial through holes 12 are provided at one position of the screw body 10, so that the retaining teeth 22 extending radially through the four radial through holes 12 extend out of the screw body 10 in order to enhance the anchoring force on the screw body 10 and make the screw body 10 less likely to be dislodged from the bone marrow tract.

[0060] In other embodiments, one location of the screw body 10 is provided with three or more radial through holes 12, which are arranged around the axial direction of the screw body 10. The number of radial through holes 12 is not limited here.

[0061] In other embodiments, multiple radial through holes 12 are respectively provided at multiple locations along the axial direction of the screw body 10 to accommodate corresponding fasteners 20, such that the retaining teeth 22 of the fasteners 20 protrude from these radial through holes 12, thereby strengthening the fixation of the screw body 10 and preventing the screw body 10 from moving out of the medullary tract. For example, combined with Figure 10 As shown, four radial through holes 12 are provided at two positions along the axial direction of the screw body 10. In this way, after the corresponding fastener 20 is configured, the retaining teeth 22 of the fastener 20 protrudes from the corresponding radial through holes 12 to enhance the fixation effect between the screw body 10 and the bone marrow tract.

[0062] In an embodiment where the screw body 10 includes a screw head section A, a screw middle section B, and a screw tail section C connected sequentially along its axial direction, the radial through hole 12 located at the same axial position of the screw body 10 may be formed in at least one of the screw head section A, screw middle section B, and screw tail section C.

[0063] In addition, combined Figures 7 to 10 As shown, in an embodiment where multiple retaining teeth 22 extend from the screw body 10, the inner wall of the axial through hole 11 is provided with multiple guide grooves 10d, so that the corresponding retaining teeth 22 can move along the guide grooves 10d to the corresponding radial through hole 12. The number of guide grooves 10d is not limited here; it can be equal to or unequal to the number of retaining teeth 22. Specifically, in a structure where the retaining teeth 22 move along the axial through hole 11 to the radial through hole 12 and extend from it, the guide grooves 10d are not necessary. In embodiments with guide grooves 10d, the guide grooves 10d provide good guidance for the retaining teeth 22, reducing the difficulty of aligning the retaining teeth 22 with the radial through hole 12, allowing the retaining teeth 22 to move quickly to the corresponding radial through hole 12, thereby improving operational efficiency.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A combined interface screw, characterized in that, include: The screw body has an axial through hole and a radial through hole. The axial through hole extends through the near end face of the screw body along the axial direction of the screw body, and the radial through hole extends through the side wall of the axial through hole along the radial direction of the screw body, so as to communicate with the axial through hole. The fastener includes an elastic portion and a retaining tooth portion connected together. When the fastener moves along the axial through-hole to such that the retaining tooth portion is opposite to the radial through-hole, the elastic portion drives the retaining tooth portion to extend out of the radial through-hole. The retaining tooth portion has a limiting surface and a tip connected to the limiting surface. When the combined interface screw is implanted into the bone marrow tract, the tip is used to anchor against the sidewall of the bone marrow tract so that the limiting surface restricts the retaining tooth portion from moving out of the bone marrow tract. The retaining tooth portion has a guide arc surface disposed opposite to the limiting surface. The tip is formed at the junction of the limiting surface and the guide arc surface. The guide arc surface is used to guide the fastener into the axial through-hole. A limiting wall is formed inside the screw body. The limiting wall is located on the side of the radial through-hole away from the proximal end face of the screw body. When the fastener moves along the axial through-hole to abut against the limiting wall, the limiting wall guides the retaining tooth portion to move radially and extend out of the radial through-hole.

2. The combined interface screw according to claim 1, characterized in that, When the retaining tooth extends from the radial through hole, the ratio of the height of the retaining tooth protruding from the screw body to the height of the screw thread is in the range of 1:2 to 5:

1.

3. The combined interface screw according to claim 1, characterized in that, The elastic part is U-shaped, and the two ends of the elastic part are provided with the retaining teeth. The screw body is provided with two radial through holes, and the two radial through holes correspond to the two retaining teeth respectively.

4. The combined interface screw according to claim 1, characterized in that, The screw body includes a screw head section, a screw middle section, and a screw tail section connected sequentially along its axial direction, and at least one of the screw head section, the screw middle section, and the screw tail section is provided with the radial through hole.

5. The combined interface screw according to claim 1 or 4, characterized in that, At least one location on the axial direction of the screw body is provided with a plurality of radial through holes.

6. The combined interface screw according to claim 5, characterized in that, The screw body is provided with a plurality of radial through holes arranged along the axial direction of the screw body.

7. The combined interface screw according to claim 1 or 4, characterized in that, The screw body is provided with a plurality of radial through holes arranged along the axial direction of the screw body.

8. The combined interface screw according to claim 1, characterized in that, The sidewall of the axial through hole is provided with a guide groove, which is connected to the radial through hole. The guide groove is used to guide the locking teeth to move within the axial through hole to be opposite to the radial through hole.

9. The combined interface screw according to claim 1, characterized in that, The axial through hole has a first groove wall and a second groove wall disposed opposite to each other, and the gap between the first groove wall and the second groove wall is used to guide the retaining tooth portion to move to be opposite to the radial through hole.

10. The combined interface screw according to claim 1, characterized in that, The distal end of the screw body includes a tapered body with a through hole. The through hole extends through the tapered body along the axial direction of the screw body and communicates with the axial through hole. The diameter of the axial through hole is larger than the diameter of the through hole.

11. The combined interface screw according to claim 10, characterized in that, The axial through hole forms a drive interface on the near end face of the screw body, and the cross-sectional shape of the drive interface is cross-shaped, regular polygonal, or quincunx-shaped.

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