Hollow bone screw extractor

Abstract

The utility model relates to a hollow bone screw extractor which is characterized by comprising a hollow main body, a screw rod and a lifting lug. An internal thread is arranged on the inner surface of the hollow main body; the hollow main body comprises a forking part and a screwing-in part; the split part comprises a plurality of split petals, one ends of the plurality of split petals are connected to the bottom of the screwing-in part, gaps are reserved among the plurality of split petals, and protruding teeth are arranged on the outer surfaces of the split petals; the interior of the screwing-in part is hollow, a plurality of lifting lugs penetrating through the side wall are arranged on the side wall of the screwing-in part, and the lifting lugs can protrude outwards in the radial direction of the hollow main body; an opening is formed in one end, far away from the split part, of the screw-in part; and the screw rod comprises a thread part, an external thread is arranged on the outer surface of the thread part, and the external thread is matched with the internal thread in the hollow main body.

Description

Technical Field

[0001] The utility model relates to the field of medical instruments, in particular to a hollow bone screw remover used in orthopedics. Background Art

[0002] At present, the application of bone plate screw internal fixation is a common method for treating fractures. With the development of orthopedic technology, new implant methods continue to emerge. New materials and technologies not only effectively restore bone stability, but also reduce the damage to bone blood supply and improve the cure rate of fractures. However, the difficulty in removing internal fixators follows. Broken nails and broken plates caused by various reasons occur from time to time in clinical practice, and removing them has become a difficult problem that plagues orthopedic surgeons in clinical practice. In clinical practice, whether it is removing implants or resetting implants, the technical problem of removing broken nails is involved. At this stage, most hospitals use osteochisels to remove the bones around the broken nails, and then use a nail remover to grasp the broken nails and remove them. This nail remover has a certain effect and there are many successful cases.

[0003] However, with the advancement of time and technology, it has been found that using osteotome to remove bone first and then using nail remover to remove broken nails has the following defects: 1) using osteotome to remove bone, a lot of bone is removed, causing great bone damage, and 2) it is inconvenient to use. The nail remover provided by the manufacturer must first rotate the T-handle clockwise to loosen the gripping head, hold the broken nail, and then rotate the handle counterclockwise to hold the broken nail tightly and remove it. The operation is cumbersome and prolongs the operation time. Utility Model Content

[0004] In order to solve the above problems, the utility model designs a hollow bone screw extractor which does not require the expansion and excavation of the screw channel.

[0005] The hollow bone screw remover of the utility model comprises a hollow body, the interior of the hollow body is provided with a through hole penetrating the hollow body, and the inner surface of the hollow body is provided with an internal thread; the hollow body comprises a forked portion and a screw-in portion; the forked portion comprises a plurality of fork petals, one end of the plurality of fork petals is connected to the bottom of the screw-in portion, a gap is left between the plurality of fork petals, and the outer surface of the fork petals is provided with protruding teeth; the screw-in portion is hollow inside, and a plurality of lifting ears are provided on the side wall of the screw-in portion, and the lifting ears can bulge outward along the radial direction of the hollow body, and an opening is provided at one end of the screw-in portion away from the forked portion; a screw rod, the screw rod comprises a threaded portion, the outer surface of the threaded portion is provided with an external thread, and the external thread cooperates with the internal thread inside the hollow body.

[0006] Furthermore, in the hollow bone screw remover as described above, an edge gap is provided between at least one edge of the ear and the side wall.

[0007] Furthermore, in the hollow bone screw remover as described above, the ear is provided with an ear protruding tooth protruding toward the outside of the hollow body; and the protruding thickness of the ear protruding tooth gradually decreases toward the bottom of the ear.

[0008] Furthermore, in the hollow bone screw remover as described above, the width of the ear is 0.5-2 mm, and the length of the ear is 2-8 mm.

[0009] Furthermore, in the hollow bone screw remover as described above, the gap between every two of the fork petals is 0.2-0.8 mm.

[0010] Furthermore, in the hollow bone screw remover as described above, the length of the forked portion accounts for 1 / 2-2 / 3 of the total length of the hollow body.

[0011] Further, in the hollow bone screw remover as described above, the number of the fork petals is two, three or four.

[0012] Furthermore, in the hollow bone screw remover as described above, a clamping cap is provided on the side wall of the screw-in portion, and the clamping cap is located around the opening of the screw-in portion.

[0013] Furthermore, in the hollow bone screw remover as described above, the external thread of the screw is a left-hand thread.

[0014] Furthermore, in the hollow bone screw remover as described above, the outer diameter of the screw is 0.5-2.5 mm and the length is 5-50 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a three-dimensional diagram of the first embodiment of the utility model.

[0016] Figure 2 This is a front view of the hollow body of the first embodiment of the utility model.

[0017] Figure 3 It is a cross-sectional view of the hollow body of the first embodiment of the utility model.

[0018] Figure 4 It is an enlarged view of the screw-in portion of the utility model.

[0019] Figure 5 It is the front view of the screw of the utility model.

[0020] Figure 6 This is a front view of the screw rod inserted into the hollow body in the first embodiment of the utility model.

[0021] Figure 7 It is a three-dimensional diagram of the second embodiment of the utility model.

[0022] Figure 8 It is a three-dimensional diagram of the third embodiment of the utility model. DETAILED DESCRIPTION

[0023] The following is a detailed description of the technical means used by the present invention to achieve the intended purpose of the present invention with reference to the drawings and preferred embodiments of the present invention.

[0024] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "one side", "one end", "one side" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, in the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0025] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of 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.

[0026] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0027] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0028] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0029] like Figure 1 As shown, the hollow bone screw extractor in the utility model comprises a hollow body 1 and a screw rod 2. The screw rod 2 can be inserted into the interior of the hollow body 1.

[0030] like Figures 1 to 3 As shown, the outer diameter of the hollow body 1 is 0.8-3 mm, and the length is 5-50 mm. The hollow body 1 comprises a forked portion 11, a screw-in portion 12, and a through hole 13 penetrating the hollow body 1. The inner surface of the through hole 13 is provided with a thread 131.

[0031] One end of the fork portion 11 is connected to the bottom end of the screw-in portion 12; the length of the fork portion 11 accounts for 2 / 1-2 / 3 of the total length of the hollow body 1. If the length of the fork portion 11 is too long, it will affect the strength of the hollow body 1. If the length of the fork portion 11 is too short, it will be difficult to ensure that the screw extractor is firmly connected to the hollow bone screw.

[0032] The front end of the forked portion 11 is an insertion end 110, and the insertion end 110 is conical. The forked portion 11 includes a plurality of forked lobes 111, and the gap between each two forked lobes 111 is 0.2-0.8 mm, so that the forked lobes can be opened to form an interference fit with the inner surface of the hollow bone screw; if the gap between the forked lobes 111 is too small, the forked lobes are not easy to be opened, and if the gap between the forked lobes 111 is too large, it will affect the strength of the hollow body 1. The outer surface of the forked lobes 111 is formed with a protruding tooth surface 111A, which increases the friction between the forked lobes 111 and the inner wall of the hollow bone screw, so that the forked lobes 111 and the inner surface of the hollow bone screw are fixed more firmly.

[0033] One end of the screw-in portion 12 is connected to the rear end 112 of the forked portion 11, and the other end is provided with an opening 120. The screw-in portion 12 is a hollow structure, and the through hole 13 penetrates the forked portion 11, the screw-in portion 12 and the opening 120 to connect the three.

[0034] Combination Figure 4As shown, the side wall 120 of the screw-in portion 12 is provided with a lug 14 penetrating the side wall. Preferably, an edge gap 121 is provided between at least one edge of the lug 14 and the side wall 120, so that the lug 14 can expand outward along the radial direction of the hollow body 1 under the action of an external force. Figure 4 As shown, the width W of the ear 14 is 0.5-2 mm, and the height H of the ear is 2-8 mm. The ear 14 is provided with an ear protruding tooth 141 protruding toward the outside of the hollow body 1, and the protruding thickness of the ear protruding tooth 141 gradually decreases toward the lower edge 142 of the ear, thereby facilitating the hollow body 1 to penetrate deeply into the connecting hole of the hollow bone screw, and better produce an interference fit effect with the connecting hole wall of the hollow bone screw after the screw 2 is screwed in.

[0035] Such as 5 and Figure 6 As shown, the screw rod 2 includes a threaded portion 21 and a nut 22, one end of the threaded portion 21 is connected to the nut 22, and the other end can be inserted into the through hole 13 of the hollow body 1 from the opening 120 of the screw-in portion 12. The outer surface of the threaded portion 21 is provided with an outer thread 211 that cooperates with the inner thread 131 on the inner surface of the through hole 13. Since most hollow bone screws are right-handed screws, it is necessary to rotate leftward when screwing the hollow bone screw through the screw rod 2. Therefore, in order to prevent the screw rod 2 from being screwed out of the hollow body 1, preferably, the outer thread of the threaded portion 21 is a left-handed thread. The outer diameter of the threaded portion is 0.5-2.5 mm, and the length of the screw rod 2 is 5-50 mm.

[0036] Before use, the hollow bone screw extractor of the utility model is located outside the hollow body 1, and the ear 14 and the fork 11 are both located at the initial position. Figure 2 When the hollow bone screw needs to be removed, the user will insert the hollow body 1 into the connecting hole of the hollow bone screw until the ear 14 is fully or partially inserted into the connecting hole of the hollow bone screw. Figure 6 As shown, the threaded portion of the screw 2 is gradually screwed into the through hole 13 of the hollow body 1 from the opening 120 of the screw-in portion 12, as shown in FIG. Figure 6 As shown. When the screw-in portion 21 of the screw rod 2 passes through the ear 14, the ear 14 will be squeezed by the screw-in portion 21 of the screw rod 2 and bulge outward, whereby the ear convex teeth 141 of the ear 14 will contact the inner wall of the connecting hole of the hollow bone screw. Continue to tighten the screw rod 2. When the screw-in portion 21 of the screw rod 2 passes through the forked portion 11, the forked flap 111 of the forked portion 11 is squeezed by the screw-in portion 21 of the screw rod 2 and expands outward, contacting the inner wall of the connecting hole of the hollow bone screw. The forked flap 111 contacts the inner wall of the connecting hole of the hollow bone screw through the convex teeth.

[0037] When the screw rod 2 is completely screwed into the through hole 13 of the hollow body 1, the ear 14 and the fork flap 111 both form an interference fit with the inner wall of the connecting hole of the bone screw, and the hollow bone screw extractor of the utility model and the hollow bone screw are fixed to each other. At this time, if the screw rod 2 is rotated to the left, the hollow bone screw extractor will rotate to the left, and further rotate the hollow bone screw to the left, thereby loosening the hollow bone screw. When the hollow bone screw is separated from the bone tissue, the hollow bone screw can be removed.

[0038] The technical means and advantages of the present invention are further described below through specific embodiments.

[0039] Example 1

[0040] like Figure 1 and Figure 2 , which is a first embodiment of the utility model, wherein the through hole 13 of the hollow body 1 is a conical hole, and the inner diameter of the through hole 13 is smaller as it is closer to the insertion end 110 of the forked portion 11. In this embodiment, the lower edge 142 of the ear 14 is connected to the side wall 120, and an edge gap 121 is provided between the remaining edge of the ear 14 and the side wall 120.

[0041] In this embodiment, the number of the fork petals 111 is two; the number of the lifting ears 14 is also two and they are distributed on both sides of the screw-in portion.

[0042] In this embodiment, a cap 122 is provided on the side wall of the screw-in portion 12 of the hollow body 1, and the cap 122 is located at the periphery of the opening 120. When in use, the cap 122 can be stuck at the hole wall of the connecting hole of the hollow bone screw to prevent the hollow body 1 from completely falling into the connecting hole of the hollow bone screw.

[0043] Example 2

[0044] like Figure 7 As shown, it is the second embodiment of the utility model. In this embodiment, the number of the fork petals 111 is 3, and the rest are the same as the design of the embodiment 1.

[0045] Example 3

[0046] like Figure 8 As shown, it is the third embodiment of the utility model. In this embodiment, the number of the fork petals 111 is 4, and the rest of the design is the same as that of the embodiment 1.

[0047] The advantages of the utility model are:

[0048] 1. The utility model can be used to remove hollow bone screws without expanding or excavating the screw channel, thereby reducing damage to bone tissue and reducing pain for patients. The utility model is simple to operate, reduces the doctor's operation time, and improves the efficiency of removing broken screws.

[0049] 2. The ear design of the utility model can control the length of the fork portion and maintain the strength of the hollow body, and the large interference fit area can ensure that the hollow body and the connecting hole of the hollow bone screw are firmly combined.

[0050] 3. The conical design of the insertion end of the forked portion of the utility model and the thickness design of the ear protruding teeth of the ear are both conducive to inserting the hollow body into the connecting hole of the hollow bone screw, reducing the difficulty of positioning.

[0051] The above description is only a preferred embodiment of the present invention, and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A hollow bone screw extractor, characterized in that: include: A hollow body, wherein a through hole penetrating the hollow body is arranged inside the hollow body, and an internal thread is arranged on the inner surface of the hollow body; the hollow body comprises a forked portion and a screw-in portion; the forked portion comprises a plurality of fork petals, one end of each of the plurality of fork petals is connected to the bottom of the screw-in portion, a gap is left between the plurality of fork petals, and protruding teeth are arranged on the outer surface of each fork petal; the screw-in portion is hollow inside, and a plurality of lifting ears penetrating the side wall are arranged on the side wall of the screw-in portion, and the lifting ears can bulge outwardly along the radial direction of the hollow body; an opening is arranged at one end of the screw-in portion away from the forked portion; The screw comprises a threaded portion, an outer surface of the threaded portion is provided with an external thread, and the external thread cooperates with the internal thread inside the hollow body.

2. The hollow bone screw extractor according to claim 1, characterized in that: An edge gap is provided between at least one edge of the lifting ear and the side wall.

3. The hollow bone screw extractor according to claim 2, characterized in that: The lifting ear is provided with a lifting ear protruding tooth protruding toward the outside of the hollow body; the protruding thickness of the lifting ear protruding tooth gradually decreases toward the bottom of the lifting ear.

4. The hollow bone screw extractor according to claim 3, characterized in that: The width of the lifting ear is 0.5-2 mm, and the length of the lifting ear is 2-8 mm.

5. The hollow bone screw extractor according to claim 1, characterized in that: The gap between each two fork petals is 0.2-0.8mm.

6. The hollow bone screw extractor according to claim 1, characterized in that: The length of the forked portion accounts for 1 / 2-2 / 3 of the total length of the hollow body.

7. The hollow bone screw extractor according to claim 1, characterized in that: The number of the fork petals is two, three or four.

8. The hollow bone screw extractor according to any one of claims 1 to 7, characterized in that: A clamping cap is arranged on the side wall of the screw-in portion, and the clamping cap is located around the opening of the screw-in portion.

9. The hollow bone screw extractor according to any one of claims 1 to 7, characterized in that: The external thread of the screw is a left-hand thread.

10. The hollow bone screw extractor according to any one of claims 1 to 7, characterized in that: The outer diameter of the screw is 0.5-2.5 mm, and the length is 5-50 mm.

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