Pedicle screw

Abstract

The utility model relates to a pedicle screw. The pedicle screw comprises a screw part and a screw seat part, the screw part comprises a screw column part and a screw head part rotationally connected with the first end of the screw column part, the second end of the screw column part is connected with the screw seat part, threads are arranged on the outer surface of the screw column part, and a plurality of V-shaped grooves are formed in the side walls of the two opposite sides of the screw head part. The nail head part is provided with a first position and a second position, when the nail head part is located at the first position, the nail head part is in a straight line shape, and the axis of the nail column part and the axis of the nail head part are located in the same straight line direction. And when the nail head part is positioned at the second position, the nail head part is bent. According to the pedicle screw, the screw head part of the pedicle screw is arranged to be in the bendable state, so that the pedicle screw is not prone to disengaging from a bone hole.

Description

Technical Field

[0001] The utility model relates to the field of medical instruments, in particular to a pedicle screw. Background Art

[0002] Pedicle screws are a type of screw used to stabilize and fix the spine and are used to treat various spinal diseases.

[0003] Pedicle screws need to provide strong fixation when in use, so the biggest risk faced by pedicle screws during use is the risk of dislodging from the bone hole.

[0004] Currently, the pedicle screws on the market are mainly solid straight titanium alloy screws. Except for the U-shaped screw head, they are no different from ordinary screws in other aspects and can easily fall out of the bone hole during use. Utility Model Content

[0005] In view of the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a pedicle screw that is not easy to fall out of the bone hole.

[0006] The purpose of this utility model is achieved through the following technical solutions:

[0007] A pedicle screw comprises a screw portion and a screw seat portion, wherein the screw portion comprises a nail column portion and a nail head portion rotatably connected to the first end of the nail column portion, the second end of the nail column portion is connected to the nail seat portion, the outer surface of the nail column portion is provided with a thread, and the side walls on opposite sides of the nail head portion are provided with a plurality of V-shaped grooves; the nail head portion is provided with a first position and a second position, when the nail head portion is located at the first position, the nail head portion is in a straight line, and the axis of the nail column portion and the axis of the nail head portion are in the same straight line direction; when the nail head portion is located at the second position, the nail head portion is in a curved shape.

[0008] Furthermore, a hollow cavity is provided in the nail head, and each of the V-shaped grooves is connected to the hollow cavity. A through hole is provided on the nail column, and the through hole is connected to the hollow cavity. A rope-like piece is provided in the through hole, and the first end of the rope-like piece extends to the outside of the pedicle screw, and the second end of the rope-like piece extends to the inside of the hollow cavity and is connected to the nail head. The connection point between the rope-like piece and the nail head is arranged close to the V-shaped groove.

[0009] Furthermore, a ring is provided at the connection point between the rope-like member and the nail head, and the rope-like member is fixed on the ring.

[0010] Furthermore, one end of the through hole extends to the outer wall of the nail seat portion, and the nail seat portion is provided with a fixing portion for fixing the rope-like component.

[0011] Furthermore, the V-shaped grooves are alternately arranged on the side walls on opposite sides of the nail head.

[0012] Furthermore, a slot is provided at the first end of the nail column, and a block is provided on the nail head that cooperates with the slot. The block can rotate in the slot with the axis of the nail column as the center; a limit block is also provided at the first end of the nail column to prevent the block from leaving the slot.

[0013] Furthermore, the card slot and the card block are both cylindrical.

[0014] Furthermore, the end of the nail head away from the nail column is conical.

[0015] Furthermore, the nail head is made of memory alloy.

[0016] Furthermore, a hollow cavity is provided in the nail head portion, and a through hole is provided on the nail column portion, the through hole is communicated with the hollow cavity, and the through hole is used for an external rod to pass through and allow the external rod to enter the hollow cavity.

[0017] Compared with the prior art, the beneficial effect of the present invention is that the pedicle screw is not easily dislodged from the bone hole by setting the screw head of the pedicle screw to a bendable state. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a front view of the pedicle screw of the utility model;

[0019] Figure 2 yes Figure 1 A magnified schematic diagram of part A in the middle;

[0020] Figure 3 yes Figure 1 A schematic diagram of a cross section BB of the pedicle screw of the first embodiment;

[0021] Figure 4 1 is a schematic diagram of the nail head in the first position according to the first embodiment of the present invention;

[0022] Figure 5 is a schematic diagram of the nail head in the second position according to the first embodiment of the present invention;

[0023] Figure 6 yes Figure 4 Enlarged schematic diagram of the middle C part;

[0024] Figure 7 This is a schematic diagram of the nail head in the second embodiment of the present invention being located in the second position.

[0025] In the picture:

[0026] 1-screw part; 1a-nail column part; 1b-nail head part; 1c-V-shaped groove; 1d-hollow cavity; 1e-through hole; 1f-block; 1g-limiting block; 2-nail seat part. DETAILED DESCRIPTION

[0027] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0028] 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., indicating positions or relationships, are based on the positions or relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] 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 internal communication 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. In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] like Figure 1 and Figure 2 As shown, in order to solve the problem that pedicle screws are easily dislodged from bone holes, the utility model discloses a pedicle screw, comprising a screw portion 1 and a screw seat portion 2, wherein the screw portion 1 is cylindrical and the screw seat portion 2 is U-shaped. The screw portion 1 is connected to the screw seat portion 2 so that the pedicle screw is Y-shaped. The screw portion 1 comprises a screw column portion 1a and a screw head portion 1b rotatably connected to the first end of the screw column portion 1a, and the second end of the screw column portion 1a is connected to the screw seat portion 2. In order to facilitate the pedicle screw to be screwed into the bone hole, the outer surface of the screw column portion 1a is provided with a thread. In order to facilitate the bending of the screw head portion 1b, a plurality of V-shaped grooves 1c are provided on the opposite side walls of the screw head portion 1b.

[0031] The nail head 1b has a first position and a second position. When the nail head 1b is in the first position, the nail head 1b is straight, and the axis of the nail column 1a and the axis of the nail head 1b are in the same straight direction. When the nail head 1b is in the second position, the nail head 1b is curved. The switching between the first and second positions of the nail head 1b can rely on the material properties of the nail head 1b itself, such as memory alloy, or the nail head 1b can be bent or straightened by an external force. The various switching methods between the first and second positions are explained in detail below.

[0032] The specific method of using the pedicle screw of the utility model is as follows:

[0033] S1, drilling a hole in the bone and tapping the hole;

[0034] S2, screwing the screw part 1 into the bone hole, at which time the screw head 1b is in the first position, that is, the screw head 1b is in a straight line;

[0035] S3, changing the nail head 1b from the first position to the second position, that is, changing the nail head 1b from a straight shape to a curved shape, so that the curved nail head 1b abuts against the inner wall of the bone hole, making it difficult for the pedicle screw to fall out of the bone hole;

[0036] S4, when the pedicle screw needs to be removed, the screw head 1b is changed from the second position to the first position, that is, the screw head 1b is changed from a curved shape to a straight shape;

[0037] S5, remove the pedicle screws.

[0038] The utility model sets the screw head 1b of the pedicle screw in a bendable state, so that the pedicle screw is not easy to fall out of the bone hole.

[0039] The pedicle screw of the present invention has a first embodiment and a second embodiment. The following mainly describes the technical solutions of the two embodiments in detail. The technical solutions other than the first embodiment and the second embodiment are collectively referred to as the technical solutions in other embodiments. Specifically:

[0040] like Figures 2 to 5As shown, in the first embodiment, the nail head 1b is driven by an external force to switch between the first position and the second position, that is, the nail head 1b is driven by an external force to bend or straighten. In detail, a hollow cavity 1d is provided in the nail head 1b, and each of the V-shaped grooves 1c is connected to the hollow cavity 1d. A through hole 1e is provided on the nail column 1a, and the through hole 1e is connected to the hollow cavity 1d. A rope-like part is provided in the through hole 1e, and the first end of the rope-like part extends to the outside of the pedicle screw, and the second end of the rope-like part extends to the inside of the hollow cavity 1d and is connected to the nail head 1b. The connection point between the rope-like part and the nail head 1b is set close to the V-shaped groove 1c. In the first embodiment, the steps for switching the nail head 1b between the first position and the second position are as follows:

[0041] S1, when the pedicle screw is not screwed into the bone hole, Figure 4 As shown, the rope is in a relaxed state, and the nail head 1b is not pulled by an external force and remains in a straight line.

[0042] S2, after the pedicle screw is screwed into the bone hole, that is, after the screw head 1b enters the bone hole, the rope-like member is pulled so that the rope-like member remains taut; since the connection point between the rope-like member and the screw head 1b is close to the V-shaped groove 1c, that is, the connection point between the rope-like member and the screw head 1b is offset from the axis of the screw head 1b; Figure 5 As shown, under the pulling of the rope, the opening of the V-shaped groove 1c close to the connection point begins to close, and the opening of the V-shaped groove 1c away from the connection point begins to expand, and the nail head 1b begins to bend, and the nail head 1b begins to abut against the inner wall of the bone hole;

[0043] S3, continue to pull the rope to further bend the nail head 1b, and the V-shaped groove 1c near the connection point is completely closed. At this time, the curvature of the nail head 1b is maximized, and the nail head 1b abuts against the inner wall of the bone hole, and the pressure of the nail head 1b on the inner wall of the bone hole is maximized;

[0044] S4, fixing the first end of the rope-like member, keeping the rope-like member taut, so that the nail head 1b remains bent;

[0045] S5. When the pedicle screw needs to be removed, the first end of the rope-like piece is loosened or the rope-like piece is cut, and the rope-like piece returns to a relaxed state. The nail head 1b gradually returns to a straight state. The pressure of the nail head 1b on the inner wall of the bone hole is small, and the pedicle screw is easier to remove from the bone hole.

[0046] In the first embodiment, the V-shaped groove 1c is designed to ensure that, when the V-shaped groove 1c is fully closed, the nail head 1b exerts sufficient pressure on the inner wall of the bone hole, making it difficult to remove the pedicle screw from the bone hole. Typically, the opening size of the V-shaped groove 1c is configured such that, when the V-shaped groove 1c is not fully closed, the pressure exerted by the nail head 1b on the inner wall of the bone hole is maximized when the V-shaped groove 1c is bent and closed. The operator can pull the rope-like member according to surgical needs and secure the first end of the rope-like member when the desired opening size of the V-shaped groove 1c is reached, i.e., when the nail head 1b exerts the desired pressure on the inner wall of the bone hole. The present invention facilitates the bending of the nail head 1b through the provision of the hollow cavity 1d, the rope-like member, and other components, and allows for adjustable bending of the nail head 1b. Bending of the nail head 1b can also be achieved using the method of the second embodiment, which will be explained in detail below and will not be further described here.

[0047] like Figure 4 He Ru Figure 5 As shown, in the first embodiment, a ring is provided at the connection point between the rope-like member and the nail head 1b. The rope-like member is a thin rope and is fixed to the ring. In other embodiments, the rope-like member can be replaced with a thin wire. The connection between the thin wire and the nail head 1b is achieved by drilling a small hole in the nail head 1b, inserting one end of the thin wire into the hole, and then welding the thin wire to the nail head 1b.

[0048] like Figure 4 He Ru Figure 5 As shown, in the first embodiment, one end of the through hole 1e extends to the outer wall of the nail base 2. The nail base 2 is provided with a fixing portion for securing the rope. This fixing portion facilitates the securing of the rope. In other embodiments, one end of the through hole 1e can also extend to the outer surface of the nail post 1a, allowing the rope to be tied to the nail post 1a.

[0049] like Figure 2 As shown, in the first embodiment, the V-shaped grooves 1c are arranged in a staggered manner on the opposite side walls of the nail head 1b. By staggering the V-shaped grooves 1c, the present invention reduces the possibility of the nail head 1b breaking during bending. In other embodiments, the V-shaped grooves 1c can be symmetrically arranged on the opposite side walls of the nail head 1b. This can better eliminate the stress caused by bending when the nail head 1b is bent, but there is a disadvantage that the nail head 1b is easily broken.

[0050] like Figure 4 and Figure 6As shown, in the first embodiment, the first end of the post portion 1a is provided with a slot, and the head portion 1b is provided with a block 1f that mates with the slot. The block 1f can rotate within the slot about the axis of the post portion 1a. A stopper 1g is also provided at the first end of the post portion 1a to prevent the block 1f from leaving the slot. During the removal of the nail head portion 1b, although the rope is not pulling to maintain the bent state, the nail head portion 1b remains bent for a long time. Since the nail head portion 1b is typically made of a material such as titanium alloy, even if the rope is released, the nail head portion 1b will not immediately return to a fully straight shape. If the post portion 1a is rigidly connected to the nail head portion 1b, the bent nail head portion 1b will also rotate during rotation of the post portion 1a, and the nail head portion 1b will continue to contact the inner wall of the bone hole, effectively scraping the inner wall of the bone hole. The present invention arranges the nail head portion 1b to be rotatable relative to the nail post portion 1a, so that during the removal of the nail head portion 1b, the nail head portion 1b does not rotate with the nail post portion 1a, thereby facilitating the removal of the nail head portion 1b. In other embodiments, a rotating shaft is provided between the nail post portion 1a and the nail head portion 1b, so that the nail post portion 1a and the nail head portion 1b are rotatably connected.

[0051] like Figure 4 and Figure 6 As shown in the first embodiment, the slot and the block 1f are both cylindrical, which makes the rotation of the nail column 1a and the nail head 1b smoother. In other embodiments, the slot can also be designed as a cube, and the block 1f is still cylindrical, so that the block 1f can rotate along its axis within the slot.

[0052] like Figure 4 and Figure 5 As shown, in the first embodiment, the end of the nail head 1b distal from the nail column 1a is conical. This conical shape facilitates entry of the nail head 1b into the bone hole. When the nail head 1b bends, the conical slope rests against the inner wall of the bone hole, increasing the contact area between the nail head 1b and the inner wall, thereby enhancing the grip of the nail head 1b on the bone hole. In other embodiments, to further enhance the grip of the nail head 1b on the bone hole, the end of the nail head 1b distal from the nail column 1a may be serrated.

[0053] The above part is the technical solution of the first embodiment of the pedicle screw of the present invention. The following describes the technical solution of the second embodiment of the pedicle screw of the present invention.

[0054] like Figure 7As shown, in the second embodiment, the nail head 1b is made of a memory alloy. At room temperature, the nail head 1b is in the first position, that is, the nail head 1b is in a straight line. After the nail head 1b enters the bone hole, it is affected by the body temperature and bends toward the side of the V-shaped groove 1c, that is, the nail head 1b is in the second position. When the pedicle screw needs to be removed from the bone hole, a temperature is applied to the nail head 1b so that the nail head 1b returns to the first position again. By making the nail head 1b of a memory alloy, the utility model makes the nail head 1b simple in structure and easy to produce. In other embodiments, on the basis of the first embodiment, the rope-like member can be replaced with a flexible control rod, and the flexible control rod can enter the hollow cavity 1d from the through hole 1e, and a retractable drive rod is provided on the side wall of the flexible control rod. When the nail head 1b is in the first position, i.e., when the nail head 1b is in a straight line, the driving rod enters the hollow cavity 1d along with the flexible control rod. At this time, the driving rod is in a retracted state and does not contact the inner wall of the hollow cavity 1d. When it is necessary to move the nail head 1b to the second position, i.e., to a bent state, the driving rod is controlled to extend, contact the inner wall of the hollow cavity 1d, and cause the nail head 1b to bend, and the flexible control rod also bends accordingly.

[0055] like Figure 7 As shown, in the second embodiment, a hollow cavity 1d is provided in the nail head 1b, and a through hole 1e is provided on the nail column 1a. The through hole 1e is connected to the hollow cavity 1d, and the through hole 1e is used for an external rod to pass through and allow the external rod to enter the hollow cavity 1d. Since the nail head 1b is made of a memory alloy, its strength is insufficient. When the nail head 1b enters the bone hole, it is necessary to use the external rod to increase the strength of the nail head 1b and prevent the nail head 1b from bending. After the nail head 1b bends, the external rod is withdrawn from the hollow cavity 1d. The utility model effectively enhances the strength of the nail head 1b by providing the external rod. In other embodiments, in order to reduce manufacturing costs, the external rod, the hollow cavity 1d and the through hole 1e may not be provided.

[0056] In summary, the present invention configures the pedicle screw head 1b to be bendable, making it less likely for the screw to fall out of the bone hole. The provision of the hollow cavity 1d, the rope-like member, and other components facilitates bending of the screw head 1b, and the degree of bending can be adjusted. The provision of the fixing portion facilitates the fixation of the rope-like member. The staggered arrangement of the V-shaped grooves 1c reduces the likelihood of the screw head 1b breaking or fracturing. The screw head 1b is configured to rotate relative to the column portion 1a, facilitating removal. The conical shape of one end of the screw head 1b increases the screw head 1b's grip on the bone hole. By making the screw head 1b from a memory alloy, the screw head 1b has a simple structure and is easy to manufacture. The provision of the external rod effectively enhances the strength of the screw head 1b.

[0057] It should be emphasized that the above are only preferred embodiments of the present invention and do not constitute any form of limitation to the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A pedicle screw, comprising a screw portion (1) and a screw seat portion (2), characterized in that: The screw portion (1) comprises a nail column portion (1a) and a nail head portion (1b) rotatably connected to the first end of the nail column portion (1a); the second end of the nail column portion (1a) is connected to the nail seat portion (2); the outer surface of the nail column portion (1a) is provided with a thread; the side walls of the nail head portion (1b) on both sides are provided with a plurality of V-shaped grooves (1c); the nail head portion (1b) is provided with a first position and a second position; when the nail head portion (1b) is located at the first position, the nail head portion (1b) is in a straight line, and the axis of the nail column portion (1a) and the axis of the nail head portion (1b) are in the same straight line direction; when the nail head portion (1b) is located at the second position, the nail head portion (1b) is in a curved shape.

2. The pedicle screw according to claim 1, characterized in that A hollow cavity (1d) is provided in the nail head (1b), and each of the V-shaped grooves (1c) is connected to the hollow cavity (1d). A through hole (1e) is provided on the nail column (1a), and the through hole (1e) is connected to the hollow cavity (1d). A rope-like part is provided in the through hole (1e), and the first end of the rope-like part extends to the outside of the pedicle screw, and the second end of the rope-like part extends to the inside of the hollow cavity (1d) and is connected to the nail head (1b). The connection point between the rope-like part and the nail head (1b) is arranged close to the V-shaped groove (1c).

3. The pedicle screw according to claim 2, characterized in that A ring is provided at the connection point between the rope-like piece and the nail head (1b), and the rope-like piece is fixed on the ring.

4. The pedicle screw according to claim 2, characterized in that One end of the through hole (1e) extends to the outer wall of the nail seat portion (2), and the nail seat portion (2) is provided with a fixing portion for fixing the rope-like component.

5. The pedicle screw according to claim 1, characterized in that The V-shaped grooves (1c) are arranged alternately on the side walls on both sides of the nail head (1b).

6. The pedicle screw according to claim 1, wherein The first end of the nail column part (1a) is provided with a slot, and the nail head part (1b) is provided with a block (1f) that matches the slot, and the block (1f) can rotate in the slot with the axis of the nail column part (1a) as the center; the first end of the nail column part (1a) is also provided with a limit block (1g) that prevents the block (1f) from leaving the slot.

7. The pedicle screw according to claim 6, characterized in that The card slot and the card block (1f) are both cylindrical.

8. The pedicle screw according to claim 1, wherein The nail head (1b) is in a conical shape at one end away from the nail column (1a).

9. The pedicle screw according to claim 1, characterized in that The nail head (1b) is made of memory alloy.

10. The pedicle screw according to claim 9, characterized in that A hollow cavity (1d) is provided in the nail head portion (1b), and a through hole (1e) is provided on the nail column portion (1a). The through hole (1e) is connected to the hollow cavity (1d), and the through hole (1e) is used for allowing an external rod to pass through and allow the external rod to enter the hollow cavity (1d).

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