A type of knock-in anti-rotation bone graft screw

Abstract

This invention discloses a hammer-in anti-rotation bone graft screw, comprising a straight, rod-shaped screw body with a flat hammering end and a drill bit at the head end. The outer wall of the screw body is provided with several barbs, and the drill bit is a truncated cone shape with a gradually expanding cross-section from head to tail. This hammer-in anti-rotation bone graft screw is implanted by hammering, thereby anchoring the bone to the defect in the posterior wall of the acetabulum, resulting in a secure connection without causing a foreign body sensation.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a knock-in anti-rotation bone graft screw. Background Technology

[0002] Developmental dislocation of the hip (DDH) is one of the most common and complex diseases in orthopedic surgery. Patients with DDH have dysplasia of the acetabulum and asymmetry of the hip head and acetabulum joints. The final outcome is often secondary osteoarthritis of the hip joint, which requires total hip replacement surgery.

[0003] In current technology, total hip replacement typically involves the use of an acetabular prosthesis in conjunction with a spacer. The spacer is used to fill the hip bone defect. Existing acetabular cups include double-cup acetabular cups, acetabular supports with loops for screw fixation, and some require bone cement. Some require screw fixation to fill bone defects. Currently, total acetabular prosthesis replacement mainly faces the following problems: 1. Effective implantation of the acetabular prosthesis is a crucial factor affecting postoperative efficacy in total hip replacement. If the posterior wall defect is too large, the contact area between the acetabular cup prosthesis and the hip bone is small, increasing the risk of prosthesis loosening and postoperative joint dislocation. 2. In cases with significant posterior wall defects, autologous bone grafting is often used for reconstruction, requiring a large amount of autologous bone. Screws are used to anchor the autologous bone to the posterior wall defect. Postoperative issues include prosthesis loosening and insecure fixation; additionally, the screw head may not be fully implanted below the bone surface.

[0004] Therefore, how to provide a knock-in anti-rotation bone graft screw that solves the above-mentioned technical problems is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a knock-in anti-rotation bone graft screw, which is implanted by knocking in to anchor the bone to the defect in the posterior wall of the acetabulum. This not only provides a firm connection but also avoids the feeling of a foreign body.

[0006] To achieve the above objectives, the present invention provides a hammer-in anti-rotation bone graft screw, comprising a straight rod-shaped screw body, the tail end of which is a flat hammering end face, the head end of which is provided with a drill head, and the outer wall of which is provided with several barbs. The drill head is a truncated cone shape with a gradually expanding cross-section from head to tail.

[0007] Preferably, the nail rod body has a hollow channel inside, which runs through the first and last ends of the nail rod body.

[0008] Preferably, the channel axis of the hollow channel is collinear with the central axis of the nail rod; the hollow channel is a column with a uniform cross-section.

[0009] Preferably, the material of the knock-in anti-rotation bone implant is polylactic acid or polyetheretherketone, which are polymeric materials.

[0010] Preferably, the outer wall of the nail rod body is provided with a plurality of raised ridges, the raised ridges starting from the tail end of the nail rod body and ending at the tail end of the drill bit, and the barbs are provided along the raised ridges and / or between the raised ridges.

[0011] Preferably, any of the protruding ridges is a straight line, and its length direction is the same as the axial direction of the nail rod.

[0012] Preferably, the outer side of the nail shank is provided with a plurality of threading holes. Preferably, all the protruding ridges are evenly arranged along the radial direction of the nail shank, and the barbs provided on the protruding ridges are evenly arranged along the length direction of the protruding ridges.

[0013] Preferably, the nail rod body, the barb, the drill bit, and the protruding ridge are integrally formed.

[0014] Preferably, the barb includes a drilling bevel facing the head end of the nail rod and a locking bevel facing the tail end of the nail rod. The angle between the direction of the drilling bevel and the axial direction of the nail rod is an obtuse angle, and the angle between the direction of the locking bevel and the axial direction of the nail rod is an acute angle or a right angle.

[0015] Compared with the above-mentioned background technology, the hammer-in anti-rotation bone graft nail provided by the present invention includes a nail rod body, the first end of the nail rod body is provided with a drill head, and the outer wall of the nail rod body is provided with a number of barbs; wherein, the nail rod body is a straight rod shape, the tail end of the nail rod body is a flat hammer end face, and the drill head is a variable cross-section frustum shape with a gradually expanding cross-section from the head to the tail.

[0016] During the operation of this hammer-in anti-rotation bone graft screw, taking the acetabulum as an example, the hammering end face of the screw shaft is hammered to implant the hammer-in anti-rotation bone graft screw in a hammering manner, thereby anchoring the bone to the defect in the posterior wall of the acetabulum. The barbs are used to prevent the screw shaft from shifting or being pulled out. Unlike traditional screws, which can become loose due to rotation after connection, this hammer-in anti-rotation bone graft screw solves this problem. Not only does the barb make the connection of the screw shaft firm, but the hammering end face of the screw shaft is also flat, so there is no protrusion and no foreign body sensation. Attached Figure Description

[0017] 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention;

[0019] Figure 2 A cross-sectional schematic diagram of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention;

[0020] Figure 3 A longitudinal sectional view of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of another knock-in anti-rotation bone graft screw provided in an embodiment of the present invention.

[0022] in:

[0023] 10-Nailing rod body, 11-Barb, 12-Drill head, 13-Protruding ridge, 14-Threading hole, 101-Hollow channel, 111-Drilling slope, 112-Locking slope. Detailed Implementation

[0024] 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.

[0025] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Please refer to Figures 1 to 4 ,in, Figure 1 This is a schematic diagram of the structure of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention. Figure 2 This is a cross-sectional schematic diagram of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention. Figure 3 This is a longitudinal sectional view of the knock-in anti-rotation bone graft screw provided in an embodiment of the present invention. Figure 4 This is a schematic diagram of another knock-in anti-rotation bone graft screw provided in an embodiment of the present invention.

[0027] In a first specific embodiment, the hammer-in anti-rotation bone graft screw provided by the present invention includes a screw rod 10, a drill head 12 at the head end of the screw rod 10, and a plurality of barbs 11 on the outer wall of the screw rod 10; wherein, the main structure of the screw rod 10 is a straight rod shape, the tail end structure of the screw rod 10 is a flat hammer end face, the drill head 12 is a variable cross-section frustum shape, the head and tail directions of the drill head 12 are the same as the head and tail directions of the screw rod 10, and the cross-section of the variable cross-section frustum shape gradually expands from the head to the tail.

[0028] In this embodiment, the rear end of the hammer-in anti-rotation bone graft is a hammering end face that can be hammered, and the front end of the hammer-in anti-rotation bone graft is the head end of the drill bit 12 with the smallest and sharpest cross-section.

[0029] Taking the acetabulum as an example, this knock-in anti-rotation acetabular bone graft screw is specifically a knock-in anti-rotation acetabular bone graft screw. During use, a pre-prepared hole with a diameter slightly larger than the tip of the drill bit 12 and smaller than the outer diameter of the screw shaft 10 is prepared at the site requiring connection, such as the area where the autologous bone and the posterior wall defect of the acetabulum need to be connected. Then, the knock-in anti-rotation acetabular bone graft screw is aligned with the autologous bone and the posterior wall defect of the acetabulum and driven in. The knock-in anti-rotation acetabular bone graft screw, implanted by knocking, anchors the bone to the posterior wall defect of the acetabulum, and the barbs 11 prevent displacement and pull-out of the screw shaft 10.

[0030] The aforementioned hammer-in anti-rotation bone graft screw differs from traditional screws. Traditional screws use threaded connections, which can rotate and loosen after implantation, leading to bone fragment dislodgement. Traditional screw fixation can result in adverse events such as prosthesis loosening and dislocation. The hammer-in anti-rotation bone graft screw solves this problem. It not only provides greater pull-out resistance through the barbs 11 and ensures a firm connection of the screw shaft 10, but also features a flat hammer end face at the tail end of the screw shaft 10 that is flush with the surrounding structure without protrusion, thus eliminating the feeling of a foreign body.

[0031] It should be noted that the nails described in this embodiment are used in various applications, including but not limited to the fixation of fracture fragments and transplanted bone, and should also fall within the scope of this embodiment.

[0032] Based on this, a sharp structure can be added to the tip of the drill head 12, so that the drill head 12 and the sharp structure as a whole are conical, which is more conducive to the drilling of the aforementioned knock-in anti-rotation bone graft screws, even in the case of no pre-hole.

[0033] In the preparation of the knock-in anti-rotation bone graft screw, the material used is a polymer material, which can be a natural polymer material or a synthetic polymer material, and should be within the scope of this embodiment.

[0034] Preferably, the material of the knock-in anti-rotation bone graft is polylactic acid or polyether ether ketone, which are polymeric materials.

[0035] Furthermore, the interior of the aforementioned knock-in anti-rotation bone graft screw is designed as a hollow structure.

[0036] Specifically, the nail rod body 10 has a hollow channel 101 inside, which runs through the first and last ends of the nail rod body 10.

[0037] In this embodiment, the hollow channel 101 has multiple functions, including but not limited to connecting the air pressure at both ends, allowing other equipment to pass through and be clamped and moved, allowing other equipment or materials to pass through and be transported, and reducing weight, etc., which should also be within the scope of this embodiment.

[0038] For example, in the description of the function of a hollow channel 101, the hollow channel 101 serves as a central hole, and its main purpose is to guide. After being positioned by Kirschner wires, the nail hole passes through the Kirschner wires and is hammered into the nail hole along the Kirschner wires.

[0039] Furthermore, the channel axis of the hollow channel 101 is collinear with the central axis of the nail rod 10, meaning that the hollow channel 101 is located at the center of the nail rod 10.

[0040] It should be noted that this embodiment only provides the hollow structure of the hollow channel 101, and does not limit its specific structural form or shape, such as circular cross-section, polygonal cross-section, etc., which should also fall within the scope of this embodiment.

[0041] For example, the hollow channel 101 is a column with a uniform cross-section everywhere.

[0042] In this embodiment, the overall structure of the nail rod 10 is an axisymmetric structure, and the centroid and center of gravity of the nail rod 10 are located at the same point.

[0043] Furthermore, the outer wall of the nail rod 10 is provided with several raised ridges 13, and the barbs 11 can be provided either along the raised ridges 13 or between the raised ridges 13.

[0044] In this embodiment, the raised ridge 13 is a strip-shaped ridge on the outer wall of the nail rod body 10. The strip-shaped ridge starts from the tail end of the nail rod body 10 and ends at the tail end of the drill bit 12. It is raised and located outside the outer diameter of the nail rod body 10.

[0045] In one configuration of the barbs 11, the barbs 11 are positioned along the raised ridge 13, such as... Figures 1 to 3 As shown, the ends of the barbs 11 converge at a single point, and the barbs 11 are generally shaped like spikes. At this time, the barbs 11 are located outside the height of the raised ridge 13. At this time, the barbs 11 may not be provided on the outer wall of the nail rod body 10 except for the part of the raised ridge 13.

[0046] In the second configuration of the barbs 11, the barbs 11 are positioned between the raised ridges 13, such as... Figure 4 As shown, the ends of the barbs 11 converge into a line, and the barbs 11 as a whole are stepped. At this time, part of the barbs 11 is lower than the height of the raised ridge 13, and the outer edge of the barbs 11 exceeds the height of the raised ridge 13.

[0047] It should be noted that the number of raised ridges 13 is not limited; in the embodiment where the barbs 11 are provided on the raised ridges 13, since the main function of the raised ridges 13 is to prevent rotation, the number of raised ridges 13 should be as large as possible. In this case, multiple raised ridges 13 are arranged as densely as possible around the outer periphery of the nail rod body 10, thereby improving the anti-rotation effect; in the embodiment where the barbs 11 are provided between the raised ridges 13, since the main function of the barbs 11 is to resist pull-out, the barbs 11 should be as wide as possible and the structural strength of the barbs 11 should be as high as possible, thereby improving the anti-pull-out effect.

[0048] Based on this, the barbs 11 can be set both between and on the raised ridges 13, thus achieving the aforementioned anti-rotation and anti-pull-out effects.

[0049] In addition, each raised edge 13 can be a continuous edge or multiple discontinuous edges, both of which should be within the scope of this embodiment; the arrangement of the barbs 11 can be continuous and equidistant or discontinuous and unequal, both of which should be within the scope of this embodiment.

[0050] Taking the setting of barbs 11 on the raised ridge 13 as an example, the raised ridge 13 is the basis for setting barbs 11. The raised ridge 13 increases the height of barbs 11 and enhances the structural stability of barbs 11. In other words, the pull-out resistance of the hammer-in anti-rotation bone graft nail is provided by the barbs 11 on several raised ridges 13. The resultant force of the barbs 11 on each raised ridge 13 acts on the raised ridge 13, and all the raised ridges 13 act on the nail rod body 10 respectively.

[0051] It should be noted that this embodiment only provides the raised structure 13, and does not limit its specific structural form and arrangement. For example, the cross-section of the raised ridge 13 can be triangular, rectangular, etc., which should also fall within the scope of this embodiment.

[0052] For example, any of the raised ridges 13 is a straight line, and its length direction is the same as the axial direction of the nail rod body 10.

[0053] In this embodiment, both the raised ridge 13 and the nail rod 10 are straight. That is, the length direction of the raised ridge 13 is the same as the axial direction of the nail rod 10, and this direction is the same as the axial direction of the hammer-in anti-rotation bone graft nail, which has better structural stability.

[0054] Furthermore, the number of raised ridges 13 is greater than or equal to two, and all raised ridges 13 are evenly arranged along the radial direction of the nail rod body 10.

[0055] For example, the number of raised ridges 13 can be four. The four raised ridges 13 are evenly arranged along the radial direction of the nail rod body 10. At this time, the included angle between adjacent raised ridges 13 is 90°. At the same time, for the barbs 11 at the same length position on the nail rod body 10, the included angle between adjacent barbs 11 is also 90°.

[0056] Furthermore, the barbs 11 provided on the raised ridge 13 are evenly arranged along the length direction of the raised ridge 13.

[0057] In this embodiment, the overall structure of the nail rod 10 together with the protruding ridge 13 and the barb 11, namely the hammer-in anti-rotation bone graft nail, is an axisymmetric structure, and the centroid and center of gravity of the hammer-in anti-rotation bone graft nail are located at the same point.

[0058] In addition, several threading holes 14 are provided on the outer side of the nail rod body 10.

[0059] In this embodiment, the thread hole 14 is a transverse hole formed in the nail body 10, through which a thread can pass; during use, it serves to connect and fix other structures with a thread. Other structures include the same bone nail or other structures that can be connected with a thread; for example, when multiple bone nails are used, a thread can be passed through the thread holes 14 of multiple bone nails to connect the multiple bone nails together, improving the usage effect.

[0060] For better technical results, the nail body 10, barb 11, drill head 12 and protruding ridge 13 are integrally molded.

[0061] In addition, the nail rod 10, barb 11, drill bit 12 and protruding ridge 13 for the assembly of parts should also be included in the scope of this embodiment.

[0062] In one specific embodiment, the barb 11 includes a drilling bevel 111 facing the head end of the nail shank 10 and a locking bevel 112 facing the tail end of the nail shank 10. The angle between the bevel direction of the drilling bevel 111 and the axial direction of the nail shank 10 is an obtuse angle, and the angle between the bevel direction of the locking bevel 112 and the axial direction of the nail shank 10 is an acute angle or a right angle.

[0063] In this embodiment, it is generally necessary to drill a hole in the bone tissue first, and then the bone screw can be hammered in. The barb 11 is tooth-shaped, and its front end drilling bevel 111 serves to drill into the structure to be connected so that the screw rod 10 can enter. Therefore, the direction of its bevel is obtuse to the axial direction of the screw rod 10. Its rear end locking bevel 112 serves to prevent the screw rod 10 from being pulled out of the connecting structure. Therefore, the direction of its bevel is acute or right to the axial direction of the screw rod 10. In addition, since the locking bevel 112 is located at the rear end, it will not have any impact during drilling.

[0064] For better technical results, this hammer-in anti-rotation bone graft not only adopts a one-piece molding design, but its material is also polymer or metal; in use, the hammer-in anti-rotation bone graft is implanted into the body using a specific tool.

[0065] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0066] The foregoing has provided a detailed description of the drive-in anti-rotation bone graft screw provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are merely for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make various improvements and modifications to this invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A knock-in anti-rotation bone graft screw, characterized in that, The device includes a straight rod-shaped nail body (10), the tail end of which is a flat hammering end face, and the head end of which is provided with a drill head (12). The outer wall of the nail body (10) is provided with several barbs (11). The drill head (12) is a truncated cone with a gradually expanding cross section from head to tail. The outer wall of the nail body (10) is provided with several protruding ridges (13). The protruding ridges (13) start from the tail end of the nail body (10) and end at the tail end of the drill head (12). The barbs (11) are provided along the protruding ridges (13) and between the protruding ridges (13). When the barb (11) is located between the raised edges (13), the barb (11) is in a stepped shape. At this time, part of the barb (11) is lower than the height of the raised edges (13), and the outer edge of the barb (11) exceeds the height of the raised edges (13).

2. The knock-in anti-rotation bone graft screw according to claim 1, characterized in that, The nail rod body (10) has a hollow channel (101) inside, which runs through the head and tail ends of the nail rod body (10).

3. The knock-in anti-rotation bone graft screw according to claim 2, characterized in that, The channel axis of the hollow channel (101) is collinear with the central axis of the nail rod (10); the hollow channel (101) is a column with an equal cross-section everywhere.

4. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, The material of the knock-in anti-rotation bone graft screw is polylactic acid or polyether ether ketone, which are high-molecular materials.

5. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, The outer side of the nail rod body (10) is provided with several thread holes (14).

6. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, Any of the protruding ridges (13) is a straight line, and its length direction is the same as the axial direction of the nail rod body (10).

7. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, All the raised ridges (13) are evenly arranged radially along the nail rod body (10), and the barbs (11) provided on the raised ridges (13) are evenly arranged along the length direction of the raised ridges (13).

8. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, The nail rod body (10), the barb (11), the drill bit (12), and the protruding ridge (13) are integrally formed.

9. The knock-in anti-rotation bone graft screw according to any one of claims 1 to 3, characterized in that, The barb (11) includes a drilling bevel (111) facing the head end of the nail rod (10) and a locking bevel (112) facing the tail end of the nail rod (10). The angle between the bevel direction of the drilling bevel (111) and the axial direction of the nail rod (10) is an obtuse angle, and the angle between the bevel direction of the locking bevel (112) and the axial direction of the nail rod (10) is an acute angle or a right angle.

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