Fixing bone screw fastening device and screw detacher

Abstract

The utility model discloses a fixing bone screw fastening device and a screw detacher, and the fixing bone screw fastening device comprises a screw which comprises a screw body part with an external thread and an elastic anti-falling part arranged at the top end of the screw body part; the elastic anti-falling part comprises an anti-falling table and an elastic piece part which are communicated to form a hollow cavity; the outer wall surface of the anti-falling table is a hemispherical surface, the outer wall surface of the elastic piece part is an arc surface, and the outer wall surface of the anti-falling table protrudes out of the elastic piece part, so that a boss is formed on the outer wall surface at the joint of the anti-falling table and the elastic piece part; at least one through notch which extends in the axial direction of the nail body part is formed in the elastic sheet part and the anti-falling table; an internal threaded hole communicated with the hollow cavity is further formed in the top of the screw body part; the bone steel plate comprises a plate-shaped main body, an anti-falling cavity and an insertion cavity, wherein the anti-falling cavity and the insertion cavity are arranged in the plate-shaped main body and are communicated with each other; the anti-disengaging table is suitable for being contained in the anti-disengaging cavity, and an annular limiting part suitable for being connected with the boss in an abutting mode is formed between the anti-disengaging cavity and the insertion cavity.

Description

Technical Field

[0001] This utility model relates to the field of surgical instrument technology, and in particular to a bone screw fastening device and screw remover. Background Technology

[0002] In orthopedic surgeries, such as those involving anterior cervical spine plate fixation of the upper and lower cervical vertebrae, fixation of the glenoid lateral dorsum plate in shoulder joint surgery, and fracture surgery to connect bone tissue on both sides of a fracture site, screw fixation is generally required. Postoperatively, there is a risk of screw loosening due to patient activity. Clinically, to prevent surgical failure caused by screw loosening, most devices involving screws have different forms of anti-loosening mechanisms, such as locking rings, cam locking devices, baffle locking devices, and threaded locking devices.

[0003] However, practical use revealed that various locking devices have certain limitations: for example, threaded locking plate systems are fixed-angle restrictive systems, making rapid fusion difficult; locking ring, cam, and baffle plate locking plate systems are all multi-part systems that require pre-assembly, and the small parts are difficult to manufacture. Cam-locking and baffle plate locking plate systems require the cam or baffle plate to lock the screw in after it has been screwed in, making the operation cumbersome. Some designs even fail to consider fracture healing or the method for surgeons to remove the screws during revision surgery, resulting in the screws having to be forcibly removed.

[0004] Therefore, for bone screw fastening devices, in order to balance the issues of preventing loosening and facilitating screw removal, further improvements to the overall structure are needed. Utility Model Content

[0005] The primary objective of this invention is to provide a bone screw fastening device to address the technical problem of improving the anti-loosening effect of screws.

[0006] The second objective of this invention is to provide a screw remover to solve the technical problem of easily removing and disassembling anti-loosening screws.

[0007] The bone screw fastening device of this utility model is implemented as follows:

[0008] A bone screw fastening device, comprising:

[0009] A screw includes a screw body with external threads and an elastic anti-dislodgement portion at the top of the screw body; the elastic anti-dislodgement portion includes an anti-dislodgement platform and a spring portion having a through-hole; the outer wall surface of the anti-dislodgement platform is hemispherical, the outer wall surface of the spring portion is arc-shaped, and the outer wall surface of the anti-dislodgement platform protrudes from the spring portion, such that a boss is formed on the outer wall surface at the junction of the anti-dislodgement platform and the spring portion; and at least one notch is provided through the spring portion and the anti-dislodgement platform and extends axially along the screw body; the top of the screw body also has an internal threaded hole communicating with the hollow cavity;

[0010] A bone plate includes a plate-shaped body and a through-connected anti-detachment cavity and an insertion cavity disposed in the plate-shaped body; the anti-detachment platform is adapted to be accommodated in the anti-detachment cavity, and an annular limiting part adapted to abut against the boss is formed between the anti-detachment cavity and the insertion cavity.

[0011] In an optional embodiment of this utility model, a tapered transition portion with an inner diameter that gradually decreases from the anti-detachment portion to the nail body portion is formed between the anti-detachment platform and the nail body portion.

[0012] In an optional embodiment of this invention, the steel plate is further provided with a transition cavity for accommodating the tapered transition portion.

[0013] In an optional embodiment of this utility model, the spring piece and the anti-detachment platform are provided with 3 to 5 notches spaced apart along the circumferential direction.

[0014] In an optional embodiment of this invention, the wall thickness of the spring piece is less than the wall thickness of the anti-detachment platform.

[0015] In an optional embodiment of this utility model, the spring piece and the anti-detachment platform share a circular arc surface facing the inner wall of the hollow cavity.

[0016] The screw remover of this utility model is implemented as follows:

[0017] A screw remover is used in the aforementioned fixed bone screw fastening device to remove the screw from the bone plate; the screw remover comprises:

[0018] A screwdriver handle, comprising a rod-shaped body and at least one protrusion disposed at the distal end of the rod-shaped body, adapted to be inserted one-to-one into at least one notch;

[0019] A pressure sleeve, fitted onto a rod-shaped body and adapted to move axially along the rod-shaped body; the pressure sleeve includes a tapered limiting portion of the tubular body located at the distal end of the tubular body, adapted to fit onto the outer side of the spring portion; and

[0020] A rotating rod adapted to penetrate the inner cavity of a rod-shaped body; the rotating rod includes a rod body and an externally threaded head located at the distal end of the rod body, adapted to mate with an internally threaded hole; the externally threaded head extends out on the side of the protrusion facing away from the rod-shaped body.

[0021] In an optional embodiment of this utility model, the inner wall of the tubular body is provided with a threaded connection portion for threaded engagement with the outer wall of the rod-shaped body.

[0022] In an optional embodiment of this invention, the proximal end of the rotating rod extends beyond the proximal end side of the rod-shaped body; and

[0023] The rod-shaped body has a rotating head near the hand for rotating the rod-shaped body, and the rotating rod has a knob near the hand for contacting the rotating head.

[0024] In an optional embodiment of this utility model, the inner diameter of the tapered limiting part gradually decreases from the distal end to the proximal end along the axial direction of the tubular body.

[0025] By adopting the above technical solution, this utility model has the following beneficial effects: The bone screw fastening device and screw remover of this utility model, through the elastic anti-dislodgement part provided on the screw and the anti-dislodgement cavity provided in the bone plate, ensure that when the screw and the bone plate are properly engaged, the elastic anti-dislodgement part is precisely confined in the anti-dislodgement cavity, thereby achieving the anti-dislodgement effect of the screw. Based on the above-mentioned bone screw fastening device, the screw can be removed from the bone plate by means of a suitable screw remover, thus making the screw and bone plate not only reliably connected but also easy to disassemble. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the screw structure of the bone screw fastening device of this utility model;

[0027] Figure 2 This is a cross-sectional view of the screw in the bone screw fastening device of this utility model.

[0028] Figure 3 This is a schematic diagram of the bone plate of the fixed bone screw fastening device of this utility model;

[0029] Figure 4 This is a schematic diagram of the fit between the bone plate and the screw in the fixed bone screw fastening device of this utility model;

[0030] Figure 5 This is a schematic diagram of the screw remover of this utility model;

[0031] Figure 6 This is a partial structural diagram of the screw remover of this utility model;

[0032] Figure 7 This is a schematic diagram of the screw remover of this utility model used for removing screws.

[0033] In the diagram: bone plate 1, anti-dislodgement cavity 11, insertion cavity 12, transition cavity 13, annular limiting part 14, nail body 21, anti-dislodgement platform 22, spring piece part 23, boss 24, notch 25, internal threaded hole 26, conical transition part 27, rod-shaped body 31, protrusion 32, rotating head 33, tubular body 41, conical limiting part 42, rotating part 43, external threaded head 51, knob 52, bone tissue 6. Detailed Implementation

[0034] To make the contents of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0035] Example 1:

[0036] Please see Figures 1 to 4 As shown, this embodiment provides a bone screw fastening device, including: a screw and a bone plate 1 for use together.

[0037] Specifically, the screw includes a screw body portion 21 with external threads and an elastic anti-dislodgement portion located at the top of the screw body portion 21. The screw body portion 21 is adapted to be inserted into the bone tissue 6 after penetrating the bone plate 1. The elastic anti-dislodgement portion forms a reliable anti-dislodgement engagement with the bone plate 1.

[0038] More specifically, the elastic anti-detachment part used in this embodiment includes an anti-detachment platform 22 with a hollow cavity formed through it and a spring piece 23. The anti-detachment platform 22 is directly connected to the nail body 21, while the spring piece 23 is located on the side of the anti-detachment platform 22 facing away from the nail body 21. In this structure, an opening communicating with the hollow cavity is formed at the end of the spring piece 23 facing away from the anti-detachment platform 22. In a preferred embodiment, the anti-detachment platform 22 and the spring piece 23 are integrally formed.

[0039] Furthermore, the outer wall of the anti-dislodgement platform 22 is hemispherical, and the outer wall of the spring plate portion 23 is arc-shaped. The outer wall of the anti-dislodgement platform 22 protrudes from the spring plate portion 23, so that a boss 24 is formed on the outer wall at the junction of the anti-dislodgement platform 22 and the spring plate portion 23. At least one notch 25 is provided on the spring plate portion 23 and the anti-dislodgement platform 22, which extends through and along the axial direction of the nail body portion 21. The top of the nail body portion 21 is also provided with an internal threaded hole 26 communicating with the hollow cavity. Based on this, when it is necessary to assemble the screw with the bone plate 1, a screwdriver with an external threaded head 51 can be used to pass through the opening into the hollow cavity and then into the internal threaded hole 26. Thus, by the fastening engagement of the screwdriver and the screw, the screwdriver can be rotated to screw the nail body portion 21 into the bone tissue 6.

[0040] In one optional embodiment, the spring portion 23 and the anti-detachment platform 22 are provided with 3 to 5 notches 25 spaced apart along the circumferential direction. Furthermore, it should be noted that the wall thickness of the spring portion 23 is less than the wall thickness of the anti-detachment platform 22. The inner wall surfaces of the spring portion 23 and the anti-detachment platform 22 facing the hollow cavity share a common arc surface.

[0041] Based on the above structure, in order to meet the requirements of screw anti-loosening, the bone plate 1 used in this embodiment includes a plate-shaped main body and an anti-loosening cavity 11 and an insertion cavity 12 that are connected through the plate-shaped main body; the anti-loosening platform 22 is adapted to be accommodated in the anti-loosening cavity 11, and an annular limiting part 14 adapted to abut against the boss 24 is formed between the anti-loosening cavity 11 and the insertion cavity 12.

[0042] Furthermore, it should be noted that a tapered transition portion 27 is formed between the anti-dislodgement platform 22 and the nail body portion 21, with the inner diameter gradually decreasing from the anti-dislodgement portion to the nail body portion 21. The bone plate 1 is also provided with a transition cavity 13 for accommodating the tapered transition portion 27.

[0043] In summary, the assembly process of the screws and the steel plate 1 used in the fixing screw fastening device of this embodiment is as follows:

[0044] As the screwdriver screws the screw into the bone plate 1 and bone tissue 6, the anti-dislodgement platform 22 first enters the insertion cavity 12 and then contacts the annular limiting part 14. At this time, due to the presence of the notch 25, both the anti-dislodgement part and the spring part 23 deform to facilitate the anti-dislodgement platform 22 to continue entering the anti-dislodgement cavity 11. As the rotational torque increases, the screw body 21 is screwed into the bone tissue 6. After the anti-dislodgement platform 22 enters the anti-dislodgement cavity 11, the tightening effect of the annular limiting part 14 on the anti-dislodgement platform 22 is released. At this time, the anti-dislodgement platform 22 and the spring part 23 return to their original shape, and the boss 24 abuts against the annular limiting part 14 in the anti-dislodgement cavity 11, so that the entire anti-dislodgement platform 22 is limited in the anti-dislodgement cavity 11 along the axial direction of the screw body 21. Thus, the screw cannot be removed from the bone plate 1 without the assistance of external tools, achieving the effect of preventing dislodgement. Furthermore, since the anti-dislodgement cavity 11 and the transition cavity 13 do not have a limiting effect on the screw in the circumferential direction, the screw can swing at a certain angle in the bone plate 1.

[0045] Example 2:

[0046] Please see Figures 1 to 7 As shown, based on the bone screw fastening device of Embodiment 1, this embodiment provides a screw remover, which is applicable to the bone screw fastening device of Embodiment 1 to remove the screw from the bone plate 1; the screw remover of this embodiment includes: a screwdriver bar, a pressure sleeve and a screwdriver bar for use.

[0047] Specifically, firstly, the screwdriver handle includes a rod-shaped body 31 and at least one protrusion 32 located at the distal end of the rod-shaped body 31, suitable for insertion into at least one notch 25. In one optional embodiment, 3 to 5 protrusions 32 are provided circumferentially at the distal end of the rod-shaped body 31.

[0048] Secondly, there is a pressure sleeve, which is fitted onto the rod-shaped body 31 and adapted to move along the axial direction of the rod-shaped body 31. The pressure sleeve includes a tapered limiting part 42 located at the distal end of the tubular body 41, adapted to fit onto the outer side of the spring piece 23. Furthermore, it should be noted that the inner wall of the tubular body 41 is provided with a threaded connection for threaded engagement with the outer wall of the rod-shaped body 31. During the loosening and tightening of the pressure sleeve relative to the screwdriver rod, the pressure sleeve can move along the axial direction of the screwdriver rod, thereby allowing the tapered limiting part 42 to engage and disengage from the spring piece 23. To facilitate the axial movement of the pressure sleeve along the screwdriver rod by rotating it, a rotating part 43 can be provided at the proximal end of the tubular body 41 for easy hand rotation.

[0049] In addition, it should be noted that the inner diameter of the tapered limiting part 42 in this embodiment gradually decreases from the distal end to the proximal end along the axial direction of the tubular body 41.

[0050] Furthermore, there is the screw rod, which is adapted to penetrate the inner cavity of the rod-shaped body 31. The screw rod includes a rod body and an external threaded head 51 located at the distal end of the rod body, adapted to mate with the internal threaded hole 26. The external threaded head 51 extends out from the side of the protrusion 32 facing away from the rod-shaped body 31. In other words, for the distal end of the entire screw remover, along the direction from the distal end to the proximal end, there is first the external threaded head 51 of the screw rod, then the protrusion 32 of the screwdriver rod, and finally the tapered limiting part 42 of the pressure sleeve. This layout is also perfectly adapted to the structure of the screw.

[0051] Based on this, it should be noted that the hand-side end of the rotating rod extends out from the hand-side end of the rod-shaped body 31; and the hand-side end of the rod-shaped body 31 is provided with a rotating head 33 for driving the rod-shaped body 31 to rotate, and the hand-side end of the rotating rod is provided with a knob 52 for abutting against the rotating head 33.

[0052] In summary, the specific usage process of the screw remover in this embodiment is as follows: With the elastic anti-dislodgement part cooperating with the bone plate 1, the external thread head 51 of the screw rod first enters the internal thread hole 26 of the screw body 21. At this time, as the screw rod rotates, the external thread gradually penetrates deeper into the internal thread hole 26, and the boss 24 on the screwdriver rod also gradually enters the notch 25. When the boss 24 and the notch 25 are in place, they are limited by the boss 24 and the notch 25. At this time, rotating the screwdriver rod causes the entire screw to rotate synchronously, which allows the screw body 21 to gradually detach from the bone tissue 6. During this process, in order to release the abutment between the boss 24 and the annular limiting part 14, the pressure sleeve is rotated so that the pressure sleeve faces the bone tissue 6. As the pressure sleeve moves to one side, the conical limiting part 42 of the pressure sleeve gradually fits onto the outside of the spring piece part 23. Since the inner diameter of the conical limiting part 42 gradually decreases from the distal end to the proximal end, the spring piece part 23 gradually retracts as the pressure sleeve continues to move toward the bone tissue 6, in cooperation with the conical limiting part 42. This causes the notch 25 to gradually decrease, and the overall anti-dislodgement platform 22 gradually retracts. When the anti-dislodgement platform 22 retracts to a certain extent (when the outer diameter of the boss 24 is smaller than the inner diameter of the annular limiting part 14), the boss 24 can release its contact with the annular limiting part 14, allowing the anti-dislodgement platform 22 to detach from the anti-dislodgement cavity 11, thereby allowing the screw to be removed from the bone plate 1.

[0053] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above are only specific embodiments of this utility model and are not intended to limit this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

[0054] In the description of this utility model, it should be understood that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0055] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," 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. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0056] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0057] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0058] In this invention, unless otherwise expressly specified and limited, "above or below" the first feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on" the first feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the first feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

Claims

1. A bone screw fastening device, characterized in that, include: A screw includes a screw body with external threads and an elastic anti-dislodgement portion at the top of the screw body; the elastic anti-dislodgement portion includes an anti-dislodgement platform and a spring portion having a through-hole; the outer wall surface of the anti-dislodgement platform is hemispherical, the outer wall surface of the spring portion is arc-shaped, and the outer wall surface of the anti-dislodgement platform protrudes from the spring portion, such that a boss is formed on the outer wall surface at the junction of the anti-dislodgement platform and the spring portion; and at least one notch is provided through the spring portion and the anti-dislodgement platform and extends axially along the screw body; the top of the screw body also has an internal threaded hole communicating with the hollow cavity; A bone plate includes a plate-shaped body and a through-connected anti-detachment cavity and an insertion cavity disposed in the plate-shaped body; the anti-detachment platform is adapted to be accommodated in the anti-detachment cavity, and an annular limiting part adapted to abut against the boss is formed between the anti-detachment cavity and the insertion cavity.

2. The bone screw fastening device according to claim 1, characterized in that, A tapered transition section is formed between the anti-detachment platform and the nail body, with the inner diameter gradually decreasing from the anti-detachment section to the nail body.

3. The bone screw fastening device according to claim 2, characterized in that, The steel plate also has a transition cavity for accommodating the tapered transition section.

4. The bone screw fastening device according to any one of claims 1 to 3, characterized in that, The spring section and the anti-detachment platform are provided with 3 to 5 notches spaced apart along the circumference.

5. The bone screw fastening device according to any one of claims 1 to 3, characterized in that, The wall thickness of the spring section is less than the wall thickness of the anti-detachment platform.

6. The bone screw fastening device according to claim 5, characterized in that, The spring section and the anti-detachment platform share a circular arc surface facing the inner wall of the hollow cavity.

7. A screw remover, characterized in that, Suitable for use in the fixed bone screw fastening device as described in any one of claims 1 to 6 to remove the screw from the bone plate; the screw remover comprises: A screwdriver handle, comprising a rod-shaped body and at least one protrusion disposed at the distal end of the rod-shaped body, adapted to be inserted one-to-one into at least one notch; A pressure sleeve, fitted onto a rod-shaped body and adapted to move axially along the rod-shaped body; the pressure sleeve includes a tapered limiting portion of the tubular body located at the distal end of the tubular body, adapted to fit onto the outer side of the spring portion; and A rotating rod adapted to penetrate the inner cavity of a rod-shaped body; the rotating rod includes a rod body and an externally threaded head located at the distal end of the rod body, adapted to mate with an internally threaded hole; the externally threaded head extends out on the side of the protrusion facing away from the rod-shaped body.

8. The screw remover according to claim 7, characterized in that, The inner wall of the tubular body is provided with a threaded connection portion for threaded engagement with the outer wall of the rod-shaped body.

9. The screw remover according to claim 7 or 8, characterized in that, The proximal end of the rotating rod extends from the proximal end side of the rod-shaped body; and The rod-shaped body has a rotating head near the hand for rotating the rod-shaped body, and the rotating rod has a knob near the hand for contacting the rotating head.

10. The screw remover according to claim 7 or 8, characterized in that, The inner diameter of the tapered limiting part gradually decreases from the distal end to the proximal end along the axial direction of the tubular body.

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