Bone cement injectable hollow pedicle screw

Abstract

The utility model relates to the technical field of pedicle screws, and discloses a bone cement injectable hollow pedicle screw which comprises a screw cap, one end of the screw cap is connected with a wire drawing fixing bolt through internal threads, the other end of the screw cap is fixedly provided with a shaft seat, the interior of the shaft seat is connected with a hollow ball shaft, and the hollow ball shaft is connected with a screw rod. A screw body is connected to the outer wall of the end, away from the shaft seat, of the hollow ball shaft, a flow guide cavity is formed in the screw body, a mud outlet hole is formed in the outer wall of the screw body, and the mud outlet hole penetrates through the inner wall of the flow guide cavity; and the flow guide pipe is arranged in the flow guide cavity in a penetrating manner. The bone cement injectable hollow pedicle screw is provided with the flow guide pipe which is used for medical staff to inject bone cement into the flow guide cavity, so that the bone cement flows out of the mud outlet hole, farthest from the screw cap, of the screw body through the flow guide cavity and then flows out of the mud outlet hole in the near end, and the discharging sequence is more scientific and stable; and the situation that the screw body is not stably fixed due to non-uniform discharging of the bone cement is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of pedicle screws, in particular to a hollow pedicle screw capable of being injected with bone cement. Background Art

[0002] Pedicle screws are generally used in spinal fracture reduction and fixation surgeries. This type of surgery only fixes the vertebral body, and the intervertebral disc between the vertebrae remains functional. The function of the screw is to reduce the fracture and maintain it in a better position. Generally, the screw needs to be removed about one year after the operation. During use, bone cement is usually poured as a reinforcement structure to assist in the anchoring of the pedicle screw.

[0003] After searching, it was found that there is a new type of bone cement injectable hollow pedicle screw with a publication number of CN220275692U, which includes: a screw tail and a screw body connected to the screw tail, and is used to solve the problem of obvious uneven distribution of bone cement along the depth direction of the screw. In this practice, the output bone cement still adopts an input method from shallow to deep. The deep part of the vertebral arch surgical point is prone to insufficient bone cement input pressure, resulting in insufficient bone cement input in the deep part of the vertebral arch fixation point, affecting the fixation effect of the screw; for this reason, we propose a bone cement injectable hollow pedicle screw. Utility Model Content

[0004] The utility model aims to provide a hollow pedicle screw injectable with bone cement to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above object, the utility model provides the following technical solution: a bone cement injectable hollow pedicle screw, comprising:

[0006] A nail cap, one end of which is connected to a wire drawing fixing bolt through an internal thread, the other end of which is fixed to an axle seat, a hollow spherical shaft is connected to the interior of the axle seat, an outer wall of one end of the hollow spherical shaft away from the axle seat is connected to a screw body, a flow guide cavity is provided inside the screw body, a mud outlet hole is provided on the outer wall of the screw body, and the mud outlet hole penetrates to the inner wall of the flow guide cavity;

[0007] The guide tube is arranged inside the guide cavity, the outer wall of one end of the guide tube is connected to an outer retaining ring, the inner wall of the end of the guide tube close to the outer retaining ring is connected to an inner retaining ring, and the end of the guide tube away from the guide cavity is connected to a trumpet-shaped injection tube.

[0008] Furthermore, a detachable structure is formed between the drawn fixing bolt and the nail cap, and the screw body is rotationally connected to the nail cap through the hollow spherical shaft and the shaft seat, and the nail cap is connected to the guide cavity through the hollow spherical shaft and the screw body.

[0009] Furthermore, the mud outlet holes are evenly distributed at equal intervals along the outer wall of the screw body, and adjacent mud outlet holes are symmetrically arranged about the central axis of the screw body, and the guide cavity and the mud outlet holes are connected.

[0010] Furthermore, the injection pipe is connected to the mud outlet hole through the guide tube and the guide cavity, and the outer retaining ring, the inner retaining ring and the guide tube are all made of medical synthetic rubber.

[0011] Furthermore, the outer retaining ring and the inner retaining ring are rotatably connected to the flow guide tube, and the flow guide tube is telescopically connected to the screw body through the outer retaining ring and the inner retaining ring.

[0012] Compared with the prior art, the beneficial effects of the utility model are:

[0013] The bone cement injectable hollow pedicle screw is provided with a guide tube, which is used by medical staff to inject bone cement into the guide cavity, so that the bone cement first flows out from the mud outlet hole at the farthest end of the screw body from the screw cap through the guide cavity, and then flows out from the proximal mud outlet hole. The discharge sequence is more scientific and stable, and the occurrence of uneven bone cement discharge causing unstable fixation of the screw body is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the main structure of the utility model in working state;

[0015] Figure 2 This is a schematic diagram of the cross-sectional structure of the nail cap and the screw body of the utility model;

[0016] Figure 3 It is a schematic diagram of the enlarged structure of the guide tube part of the utility model.

[0017] In the figure: 1. nail cap; 2. drawing fixing bolt; 3. shaft seat; 4. hollow ball shaft; 5. screw body; 6. flow guide cavity; 7. mud outlet hole; 8. flow guide pipe; 9. outer retaining ring; 10. inner retaining ring; 11. injection pipe. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] The utility model provides a bone cement injectable hollow pedicle screw through improvement. Figure 1-Figure 2, including: a nail cap 1, one end of the nail cap 1 is connected with a wire drawing fixing bolt 2 through an internal thread, and a detachable structure is formed between the wire drawing fixing bolt 2 and the nail cap 1, and the wire drawing fixing bolt 2 is used to connect and tighten the vertebral arch wire drawing on the inner side of the nail cap 1 to facilitate the operation; the other end of the nail cap 1 is fixed with an axle seat 3, and the interior of the axle seat 3 is connected with a hollow ball shaft 4, and the outer wall of the end of the hollow ball shaft 4 away from the axle seat 3 is connected with a screw body 5, and the screw body 5 is rotatably connected to the nail cap 1 through the hollow ball shaft 4 and the axle seat 3, and the hollow ball shaft 4 is used to enable the screw body 5 to be rotatably adjusted on one side of the axle seat 3 of the nail cap 1. A guide cavity 6 is provided inside the screw body 5, and the nail cap 1 is connected to the guide cavity 6 through the hollow spherical shaft 4 and the screw body 5. A mud outlet hole 7 is provided on the outer wall of the screw body 5, and adjacent mud outlet holes 7 are symmetrically arranged about the central axis of the screw body 5. The mud outlet holes 7 penetrate the inner wall of the guide cavity 6, and the mud outlet holes 7 are evenly distributed along the outer wall of the screw body 5 at equal distances, and the guide cavity 6 and the mud outlet holes 7 are connected. The mud outlet holes 7 are used to input the bone cement injected by medical staff through the nail cap 1 and the screw body 5 into the patient's vertebral arch surgical site for fastening the pedicle screws.

[0020] See also Figure 2-Figure 3 A bone cement injectable hollow pedicle screw comprises: a guide tube 8, which is arranged inside a guide cavity 6, an outer retaining ring 9 is connected to the outer wall of one end of the guide tube 8, an inner retaining ring 10 is connected to the inner wall of one end of the guide tube 8 close to the outer retaining ring 9, the outer retaining ring 9 and the inner retaining ring 10 are connected to the guide tube 8 to form a rotation connection, and the outer retaining ring 9, the inner retaining ring 10 and the guide tube 8 are all made of medical synthetic rubber, and the guide tube 8 is telescopically connected to the screw body 5 through the outer retaining ring 9 and the inner retaining ring 10, and the guide tube 8 is used by medical staff to inject bone cement into the guide cavity 6, and through the outer retaining ring 9 and the inner retaining ring 10 In the expanded state, the bone cement first flows out from the mud outlet hole 7 at the farthest end of the screw body 5 from the nail cap 1 through the guide cavity 6, and then the bone cement flows out from the multiple groups of mud outlet holes 7 on the screw body 5 in sequence through the pulling of the medical staff, thereby reducing the occurrence of the situation where the screw body 5 is not fixed firmly due to uneven bone cement discharge; the end of the guide tube 8 away from the guide cavity 6 is connected with a trumpet-shaped injection tube 11, and the injection tube 11 is connected to the mud outlet hole 7 through the guide tube 8 and the guide cavity 6. The injection tube 11 is convenient for medical staff to inject bone cement into the guide cavity 6 through the enlarged opening, which is convenient for operation.

[0021] Working principle: For this type of bone cement injectable hollow pedicle screw, the medical staff first screws the screw body 5 into the patient's vertebral arch surgical point, selects a suitable volume of bone cement according to the depth of the screw body 5, and injects the prepared bone cement into the guide tube 8 through the injection tube 11 connected to one end of the guide tube 8. The injected bone cement is transported by the guide tube 8 and first enters the deepest part of the guide cavity 6 in the screw body 5, and is released and output through the deepest mud outlet hole 7. Then, as the medical staff withdraws the guide tube 8, the output position of the bone cement in the guide cavity 6 slowly moves from the deepest part to the shallower part, and more bone cement is input. When the guide tube 8 is pulled out, the outer retaining ring 9 and the inner retaining ring 10 will be pushed to slowly extend the guide tube 8, and the pressure at the anchoring point will not increase due to excessive bone cement input. The bone cement is scientifically released from the inside to the outside at the patient's surgical position, and the inside is solidified first, so that the fixing effect of the screw body 5 after anchoring is better, and when the guide tube 8 is pulled out, the guide tube 8 can be smoothly pulled out through the contraction of the outer retaining ring 9 and the inner retaining ring 10. Finally, the nail cap 1 is provided with an internal thread matching the wire drawing fixing bolt 2, which is convenient for connecting multiple fixed screw bodies 5, and the rotation angle of the installed screw body 5 and the nail cap 1 can be adjusted through the shaft seat 3 and the hollow ball shaft 4.

[0022] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A bone cement injectable hollow pedicle screw, characterized in that: include: A nail cap (1), one end of the nail cap (1) is connected to a wire drawing fixing bolt (2) through an internal thread, the other end of the nail cap (1) is fixed to an axle seat (3), the interior of the axle seat (3) is connected to a hollow spherical shaft (4), the outer wall of one end of the hollow spherical shaft (4) away from the axle seat (3) is connected to a screw body (5), a guide cavity (6) is provided inside the screw body (5), a mud outlet hole (7) is provided on the outer wall of the screw body (5), and the mud outlet hole (7) penetrates to the inner wall of the guide cavity (6); A flow guide tube (8) is arranged inside the flow guide cavity (6); an outer wall at one end of the flow guide tube (8) is connected to an outer retaining ring (9); an inner wall at one end of the flow guide tube (8) close to the outer retaining ring (9) is connected to an inner retaining ring (10); and an end of the flow guide tube (8) away from the flow guide cavity (6) is connected to a trumpet-shaped injection tube (11).

2. The bone cement injectable hollow pedicle screw according to claim 1, characterized in that: The wire drawing fixing bolt (2) and the nail cap (1) form a detachable structure, and the screw body (5) is rotatably connected to the nail cap (1) via the hollow spherical shaft (4) and the shaft seat (3), and the nail cap (1) is connected to the guide cavity (6) via the hollow spherical shaft (4) and the screw body (5).

3. The bone cement injectable hollow pedicle screw according to claim 1, characterized in that: The mud outlet holes (7) are evenly distributed at equal intervals along the outer wall of the screw body (5), and adjacent mud outlet holes (7) are symmetrically arranged about the central axis of the screw body (5), and the guide cavity (6) and the mud outlet holes (7) are connected.

4. The bone cement injectable hollow pedicle screw according to claim 1, characterized in that: The injection pipe (11) is connected to the mud outlet hole (7) via the guide pipe (8) and the guide cavity (6), and the outer retaining ring (9), the inner retaining ring (10) and the guide pipe (8) are all made of medical synthetic rubber.

5. The bone cement injectable hollow pedicle screw according to claim 1, characterized in that: The outer retaining ring (9) and the inner retaining ring (10) are rotatably connected to the flow guide tube (8), and the flow guide tube (8) is telescopically connected to the screw body (5) through the outer retaining ring (9) and the inner retaining ring (10).

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