Flexible porous oversleeve for medical internal fixation screw

Abstract

The flexible porous oversleeve comprises a hollow cylindrical oversleeve body, the shape and size of an inner cavity of the oversleeve body are matched with those of the matched inner fixing screw, the oversleeve body is used for being arranged on the outer side face of the inner fixing screw in an interference sleeving mode, and the oversleeve body and the inner fixing screw are integrally implanted into a bone pre-drilling hole. The oversleeve body is integrally formed by materials with elasticity and biocompatibility, through hole structures are evenly distributed on the side wall of the oversleeve body and used for being arranged between a bone pre-drilling hole and an internal fixing screw driven into the pre-drilling hole in a lining mode in an operation, and the oversleeve body is integrally formed by materials with elasticity and biocompatibility. According to the structure, hard contact between a screw and a bone under the condition of a traditional operation can be converted into flexible contact matching with flexible buffering, local stress concentration is avoided, the situation that the bone structure is damaged by a fixing screw and is not prone to loosening is effectively avoided, and the fixing stability of the inner screw is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of medical devices, and in particular to a flexible porous sleeve for medical internal fixation screws. Background Art

[0002] Internal fixation screws are a commonly used medical device in orthopedic surgery. They are mainly used to fix fractures or repair bone defects. The screws achieve the purpose of fixing fractures by virtue of the close engagement of the screw threads with the bone. If used properly, they can better maintain the effect of reduction and internal fixation for certain fractures. However, the direct contact between traditional internal fixation screws and bones may lead to a series of problems, including screw loosening, bone damage, and loose fixation. At present, these hidden dangers of using internal fixation screws cannot be completely eliminated by improving the screws or other methods of operation. Therefore, this type of surgery using internal fixation screws still poses certain safety risks to patients.

[0003] In summary, the internal fixation screws used in existing orthopedic surgeries have technical problems such as loosening, bone damage, and weak fixation. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the internal fixation screws used in existing orthopedic surgeries are loose, damage bones and are not firmly fixed.

[0005] In order to solve the above problems, the present invention provides a flexible porous sleeve for medical internal fixation screws, including a hollow cylindrical sleeve body, the shape and size of the internal cavity of the sleeve body are adapted to the matched internal fixation screw, and is used to be interference fit around the outer side of the internal fixation screw and be implanted into a pre-drilled hole in the bone together with the internal fixation screw. The sleeve body is integrally formed of a material having elasticity and biocompatibility, and the side wall of the sleeve body is evenly distributed with a through-hole structure.

[0006] The flexible porous sleeve provided by the present invention is used to be sleeved between the pre-drilled hole of the bone and the internal fixation screw driven into the pre-drilled hole during internal fixation screw surgery. The sleeve body is integrally formed of a material with elasticity and biocompatibility, and multiple through holes are arranged on the sleeve body. Through such a structure, the hard contact between the screw and the bone in the traditional surgery can be converted into a flexible contact cooperation with flexible buffering, and this flexible cooperation method can also increase the actual contact area between the fixing screw and the pre-drilled hole of the bone, avoid local stress concentration, effectively avoid damage to the bone structure by the fixing screw, and is less likely to loosen than hard contact, thereby enhancing the stability of internal screw fixation; and the porous structure distributed on the sleeve body is verified by finite element analysis and biomechanical experiments, which is conducive to the sleeve body maintaining elasticity under pressure, effectively reducing the damage to the bone structure caused by friction, and improving the healing of bones, and effectively solving the technical problems of loosening, bone damage and loose fixation of the internal fixation screws used in existing orthopedic surgeries.

[0007] As a preferred solution, the outer peripheral surface of the sleeve body is provided with an anti-skid pattern structure to increase the friction between the sleeve body and the pre-drilled bone hole. In order to prevent the sleeve body from shifting or sliding after surgery, an anti-skid pattern structure is designed on the outer side of the sleeve body. These patterns can significantly increase the friction between the flexible sleeve and the inner surface of the pre-drilled bone hole, thereby preventing the sleeve body from shifting or falling off during or after the internal fixation screw implantation process, and ensuring the stability of the screw in the bone.

[0008] As a preferred solution, the anti-skid pattern structure is a plurality of anti-skid rings integrally connected to the outer peripheral surface of the sleeve body, the anti-skid rings are spaced at a preset distance and distributed along the axial direction of the sleeve body. This design provides a preferred anti-skid pattern structure design, which is a multi-circle protruding ring structure, has a simple structure, is easy to process and has a significant effect of increasing friction.

[0009] As a preferred solution, the anti-slip ring is provided with an arc-shaped chamfered surface on the edge of the end surface facing the tip of the internal fixing screw, and the other end surface of the anti-slip ring is flat. This design provides a further optimization of the anti-slip ring structure based on the structure of the above-mentioned anti-slip ring. The edge of the end surface on the side facing the tip of the internal fixing screw is an arc surface, and the edge on the other side is a right-angled edge. Through such a structure, it is easy to insert the sleeve body into the pre-drilled hole of the bone, and secondly, it has a good positioning effect in the reverse direction, making it difficult for the sleeve body that has been inserted into the pre-drilled hole of the bone to fall out in the reverse direction.

[0010] As a preferred solution, the sleeve body is integrally connected with an annular limiting boss on the outer side surface of one end of the base of the internal fixing screw to limit the depth of the sleeve body implanted into the pre-drilled hole of the bone. This design further optimizes the sleeve body structure. The upper part of the sleeve body, that is, the end facing the base of the internal fixing screw, is provided with an annular limiting boss to limit the depth of the sleeve body inserted into the pre-drilled hole of the bone, preventing the sleeve body from being excessively pushed into the bone during the implantation of the internal fixing screw, thereby ensuring stability during the implantation process.

[0011] As a preferred solution, the inner side wall of the sleeve body has a taper corresponding to the shape of the internal fixing screw. This design optimizes the insertion fit between the inner cavity of the sleeve body and the internal fixing screw, and the taper adapted to the shape of the internal fixing screw is set in the inner cavity of the sleeve body, making the fit between the two more stable.

[0012] As a preferred solution, the inner wall of the sleeve body has a spiral pattern to increase the friction between the sleeve body and the internal fixation screw. Based on the above structure, this design provides a spiral pattern on the inner wall of the sleeve body to increase the friction between the sleeve body and the internal fixation screw, effectively preventing the internal fixation screw from falling out of the sleeve body after implantation.

[0013] As a preferred solution, the outer side of the sleeve body is evenly and densely covered with a microporous structure, and the pore size range of the microporous structure is 50μm-200μm. The outer surface of the sleeve body of this design is provided with micropores, and the hole diameter and density of the micropores are optimized and designed, and the hole diameter range is controlled between 50 microns and 200 microns to promote the growth and ingrowth of bone cells in the holes, while increasing the surface area of ​​the sleeve body and further enhancing the bonding force with the bone. By optimizing the design of the microporous structure, the sleeve body can effectively disperse stress concentration and reduce the possibility of screw loosening.

[0014] As a preferred solution, the outer side of the sleeve body is provided with a hydroxyapatite coating. In this design, the outer surface of the sleeve body is coated with a layer of hydroxyapatite (HA). This bioactive coating can effectively promote the attachment and growth of bone cells, thereby accelerating the bonding process between bones and implants. In addition, due to the dense microporous structure on the surface of the sleeve body, the coating can better penetrate into the holes, thereby increasing the bonding area with the bone tissue. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic structural diagram of a flexible porous sleeve for medical internal fixation screws provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the side cross-sectional structure of a flexible porous sleeve for medical internal fixation screws; Figure 3 for Figure 1 A schematic diagram of the integrated structure of a flexible porous sleeve and an internal fixation screw for medical internal fixation screws; in, Figure 1-Figure 3 middle: 1. Sleeve body; 2. Anti-slip ring; 3. Annular limiting boss; 4. Through hole structure; 5. Spiral pattern; 6. Internal fixing screw. DETAILED DESCRIPTION

[0016] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0017] Before explaining the working principle of the present invention in detail, the description of the present invention needs to be further explained: In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0018] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, an indirect connection through an intermediate medium, or a welding connection between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0019] refer to Figure 1-Figure 3 The following embodiments are described, Figure 1 A schematic structural diagram of a flexible porous sleeve for medical internal fixation screws provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the side cross-sectional structure of a flexible porous sleeve for medical internal fixation screws; Figure 3 for Figure 1 Schematic diagram of the integrated structure of a flexible porous sleeve and an internal fixation screw for medical internal fixation screws.

[0020] A flexible porous sleeve for medical internal fixation screws provided in this embodiment includes a hollow cylindrical sleeve body 1. The shape and size of the internal cavity of the sleeve body 1 are adapted to the matched internal fixation screw 6. The sleeve body 1 is used for interference fitting on the outer side of the internal fixation screw 6 and is implanted into a pre-drilled hole in the bone together with the internal fixation screw 6. The sleeve body 1 is integrally formed of a material having elasticity and biocompatibility, and the side wall of the sleeve body 1 is evenly distributed with a through hole structure 4.

[0021] The flexible porous sleeve provided by the present invention is used to be sleeved between the pre-drilled hole in the bone and the internal fixation screw 6 driven into the pre-drilled hole during internal fixation screw surgery. The sleeve body is integrally formed of a material with elasticity and biocompatibility, and multiple through holes are arranged on the sleeve body 1. Through such a structure, the hard contact between the screw and the bone in traditional surgery can be converted into a flexible contact cooperation with flexible buffering. This flexible cooperation method can also increase the actual contact area between the fixing screw and the pre-drilled hole in the bone, avoid local stress concentration, effectively avoid damage to the bone structure by the fixing screw, and is less likely to loosen than hard contact, thereby enhancing the stability of internal screw fixation. The porous structure distributed on the sleeve body 1 has been verified by finite element analysis and biomechanical experiments, which is conducive to the sleeve body 1 maintaining elasticity under pressure, effectively reducing the damage to the bone structure caused by friction, and improving the healing of bones, effectively solving the technical problems of loosening, bone damage, and loose fixation of the internal fixation screw 6 used in existing orthopedic surgery.

[0022] In the technical solution provided in this embodiment, the outer peripheral surface of the sleeve body 1 is provided with an anti-skid pattern structure to increase the friction between the sleeve body 1 and the pre-drilled bone hole. In order to prevent the sleeve body 1 from shifting or sliding after surgery, an anti-skid pattern structure is designed on the outer side of the sleeve body 1. These patterns can significantly increase the friction between the flexible sleeve and the inner surface of the pre-drilled bone hole, thereby preventing the sleeve body 1 from shifting or falling off during or after the implantation of the internal fixation screw 6, and ensuring the stability of the screw in the bone.

[0023] In the technical solution provided in this embodiment, the anti-skid pattern structure is a plurality of anti-skid rings 2 integrally connected to the outer peripheral surface of the sleeve body 1, and the anti-skid rings 2 are spaced at a preset distance and distributed along the axial direction of the sleeve body 1. This design provides a preferred anti-skid pattern structure design, which is a multi-circle protruding ring structure, has a simple structure, is easy to process and form, and has a significant effect of increasing friction.

[0024] In the technical solution provided by this embodiment, the anti-slip ring 2 is provided with an arc-shaped chamfered surface on the edge of the end surface on one side facing the tip of the matched internal fixing screw 6, and the end surface on the other side of the anti-slip ring 2 is flat. This design provides a further optimization of the structure of the anti-slip ring 2 based on the structure of the above-mentioned anti-slip ring 2. The edge of the end surface on one side facing the tip of the internal fixing screw 6 is an arc surface, and the edge on the other side is a right-angled edge. Through such a structure, it is easy to insert the sleeve body 1 into the pre-drilled hole of the bone, and secondly, it has a good positioning effect in the reverse direction, making it difficult for the sleeve body 1 inserted into the pre-drilled hole of the bone to fall out in the reverse direction.

[0025] In the technical solution provided in this embodiment, the sleeve body 1 is integrally connected with an annular limiting boss 3 on the outer side surface of one end of the base of the matched internal fixing screw 6 to limit the depth of the sleeve body 1 implanted into the pre-drilled hole of the bone. This design further optimizes the structure of the sleeve body 1. The upper part of the sleeve body 1, that is, the end facing the base of the internal fixing screw 6, is provided with an annular limiting boss 3 to limit the depth of the sleeve body 1 inserted into the pre-drilled hole of the bone, preventing the sleeve body 1 from being excessively pushed into the bone during the implantation of the internal fixing screw 6, thereby ensuring stability during the implantation process.

[0026] In the technical solution provided in this embodiment, the inner side wall of the sleeve body 1 has a taper corresponding to the shape of the matched internal fixing screw 6. This design optimizes the insertion fit between the inner cavity of the sleeve body 1 and the internal fixing screw 6, and the taper adapted to the shape of the internal fixing screw 6 is set in the inner cavity of the sleeve body 1, so that the fit between the two is more stable.

[0027] In the technical solution provided in this embodiment, the inner wall of the sleeve body 1 has a spiral pattern 5 to increase the friction between the sleeve body 1 and the internal fixing screw 6. Based on the above structure, the design provides a spiral pattern 5 on the inner wall of the sleeve body 1, thereby increasing the friction between the sleeve body 1 and the internal fixing screw, and effectively preventing the internal fixing screw 6 from falling out of the sleeve body 1 after implantation.

[0028] In the technical solution provided in this embodiment, the outer side of the sleeve body 1 is evenly and densely covered with a microporous structure, and the pore size range of the microporous structure is 50μm-200μm. The outer surface of the sleeve body 1 of this design is provided with micropores, and the hole diameter and density of the micropores are optimized and designed, and the hole diameter range is controlled between 50 microns and 200 microns to promote the growth and growth of bone cells in the holes, while increasing the surface area of ​​the sleeve body 1 and further enhancing the bonding force with the bone. By optimizing the design of the microporous structure, the sleeve body 1 can effectively disperse stress concentration and reduce the possibility of screw loosening.

[0029] In the technical solution provided in this embodiment, a hydroxyapatite coating is provided on the outer side of the sleeve body 1. In this design, a layer of hydroxyapatite (HA) is coated on the outer surface of the sleeve body 1. This bioactive coating can effectively promote the attachment and growth of bone cells, thereby accelerating the bonding process between bones and implants. In addition, due to the dense microporous structure on the surface of the sleeve body 1, the coating can better penetrate into the holes, thereby increasing the bonding area with the bone tissue.

[0030] The implantation process of the internal fixation screw 6 using the sleeve body 1 of the present application is as follows: during the operation, first drill a hole at a designated position of the bone, and insert the sleeve body 1 into the pre-drilled hole. Due to the action of the annular limiting boss 3, the sleeve body 1 is naturally stuck at the opening of the pre-drilled hole in the bone to prevent it from being pushed in too far. Subsequently, the internal fixation screw 6 is implanted along the inner wall of the sleeve body 1. As the internal fixation screw 6 gradually penetrates deeper, an expansion effect will be produced at the lower part of the sleeve body 1 to ensure close contact between the screw and the bone. At the same time, the anti-slip texture structure further increases the stability of the implantation system, and the microporous structure and hydroxyapatite coating can promote the rapid combination of the internal fixation screw 6 with the bone. After surgery, due to the elasticity and surface design of the sleeve body 1, the internal fixation screw 6 can be slightly moved within a certain range without loosening, which helps to reduce the risk of postoperative complications and improve the patient's rehabilitation effect.

[0031] Clinical application example: The flexible porous sleeve provided in the embodiment of the present application can be widely used in the fields of fracture fixation, joint replacement, spinal correction, etc. in orthopedic surgery. In actual application, through clinical tests on multiple patients, the application effect of the sleeve body 1 in operations such as fracture fixation and spinal correction was verified. After the operation, the flexible porous sleeve and the screw formed a stable fixed structure, and the patient's postoperative rehabilitation progressed smoothly, without loosening of screws or bone damage, which fully demonstrated the effectiveness and practicality of the present invention.

[0032] Although the embodiments of the present invention are disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A flexible porous sleeve for medical internal fixation screws, characterized in that: The invention comprises a hollow cylindrical sleeve body (1), wherein the shape and size of the internal cavity of the sleeve body (1) are adapted to the matched internal fixing screw (6), and is used to be interference fit on the outer side of the internal fixing screw (6), and to be integrally implanted with the internal fixing screw (6) into a pre-drilled hole in a bone. The sleeve body (1) is integrally formed of a material having elasticity and biocompatibility, and the side wall of the sleeve body (1) is uniformly distributed with through-hole structures (4).

2. The flexible porous sleeve for medical internal fixation screws according to claim 1, characterized in that: The outer peripheral surface of the sleeve body (1) is provided with an anti-slip texture structure to increase the friction between the sleeve body (1) and the pre-drilled hole in the bone.

3. The flexible porous sleeve for medical internal fixation screws according to claim 2, characterized in that: The anti-slip pattern structure is a plurality of anti-slip ring bodies (2) integrally connected to the outer peripheral surface of the sleeve body (1); the anti-slip ring bodies (2) are spaced at a preset distance and are distributed along the axial direction of the sleeve body (1).

4. The flexible porous sleeve for medical internal fixation screws according to claim 3, characterized in that: The anti-slip ring body (2) is provided with an arc-shaped chamfered surface on the edge of the end surface on one side facing the tip of the matched internal fixing screw (6), and the other end surface of the anti-slip ring body (2) is flat.

5. The flexible porous sleeve for medical internal fixation screw according to any one of claims 1 to 4, characterized in that: The sleeve body (1) is integrally connected with an annular limiting boss (3) on the outer side surface of one end of the base of the corresponding internal fixing screw (6) to limit the depth of the sleeve body (1) implanted into the pre-drilled hole in the bone.

6. The flexible porous sleeve for medical internal fixation screws according to claim 5, characterized in that: The inner side wall of the sleeve body (1) has a taper corresponding to the shape of the matched internal fixing screw (6).

7. The flexible porous sleeve for medical internal fixation screws according to claim 6, characterized in that: The inner side wall of the sleeve body (1) has a spiral pattern (5) to increase the friction between the sleeve body and the matching internal fixing screw (6).

8. The flexible porous sleeve for medical internal fixation screws according to claim 1, characterized in that: The outer side surface of the sleeve body (1) is evenly and densely covered with microporous structures, and the pore size range of the microporous structures is 50 μm-200 μm.

9. The flexible porous sleeve for medical internal fixation screw according to claim 1, characterized in that: The flexible porous sleeve for medical internal fixation screws according to claim 1, characterized in that the outer side of the sleeve body (1) is provided with a hydroxyapatite coating.

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