A spinal bone hook

Abstract

The present invention discloses a spinal bone hook, which belongs to the technical field of medical devices. The spinal bone hook includes: a nail cap, which is provided with a through hole along the axis; a pressure block, which is arranged in the through hole; an elastic expansion ring, which is a non-closed ring with an opening arranged in the through hole and is located below the pressure block; a universal ball head hook, which includes a ball head and a hook body, and the ball head is located at one end of the hook body; wherein the ball head is arranged between the pressure block and the elastic expansion ring and can rotate in the nail cap, and the elastic expansion ring can limit the ball head from falling out of the nail cap. The present invention provides a spinal bone hook, and the universal ball head hook can rotate and swing at any angle within a certain area to realize a universal function, so that the surgical process is convenient for bone hook installation, system resetting and lifting, and insertion of connecting rods.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to a spinal bone hook. Background Art

[0002] At present, the nail-rod-hook internal fixation system commonly used in clinical treatment of spinal degeneration, trauma, tumors and orthopedic surgery is mainly composed of pedicle screws, bone hooks, metal rods and locking top wires. When the patient's vertebral structure is abnormal or osteoporotic, the bone hook and pedicle screw structure are often used in combination. There are basically two types of bone hooks, including pedicle hooks and lamina hooks. Pedicle hooks are used for firm fixation of the thoracic spine. They are inserted through the small joint space and embedded in the pedicles; lamina hooks are used for fixation of the cervical, thoracic and lumbar vertebrae. Depending on the direction of the required stress and the site of stress action, the lamina hook can be placed on the upper or lower edge of the lamina or on the transverse process.

[0003] The installation of bone hooks in the nail-rod-hook internal fixation system in clinical use has the following deficiencies: According to the characteristics of the lamina, transverse process and pedicle in human vertebral anatomy, the lamina and transverse process are close to the midline of the spinous process, and on the inner side of the pedicles on both sides, the lamina has an inclination angle relative to the pedicle in the sagittal and coronal planes, resulting in poor adhesion of the existing fixed bone hooks to the vertebral body, which can easily lead to loosening and displacement of the bone hooks during and after surgery. The lumbar pedicles themselves have a certain outward inclination and head-to-tail angle, which causes the pedicle screw insertion angle to be inclination to varying degrees, so that the sagittal planes of the bone hooks and the pedicle screw caps are not in the same plane.

[0004] Based on the above situation, since the existing bone hook has no angle adjustment function and a single fixing direction, the following situations will occur:

[0005] 1. Difficult installation: It is difficult to place the connecting rod into the bone hook, so the connecting rod needs to be pre-bent during the operation and the direction of the connecting rod needs to be constantly adjusted to adapt, which makes installation difficult;

[0006] 2. Lateral prolapse of the bone hook or vertebral rupture: If the connecting rod changes significantly, not only will the fatigue strength of the connecting rod be reduced, but stress concentration will also be easily generated, which may easily lead to lateral prolapse of the bone hook or vertebral rupture.

[0007] 3. When the connecting rod needs to be rotated, the bone hooks implanted in the middle of the vertebral body may become loose and cut out with the rotation. These bone hooks usually need to be repositioned at least once during the rod rotation process, which increases the operation time and iatrogenic injury. Summary of the invention

[0008] In view of the shortcomings of the prior art, the object of the present invention is to provide a spinal bone hook to solve the defects of the conventional spinal bone hook in the prior art, that is, the hook has no angle adjustment and has a single fixing direction.

[0009] To achieve this object, the present invention adopts the following technical solutions:

[0010] A spinal bone hook, comprising:

[0011] A nail cap having a through hole arranged along the axis thereof;

[0012] A pressing block, which is arranged in the through hole;

[0013] An elastic expansion ring, which is a non-closed ring with an opening disposed in the through hole and located below the pressing block;

[0014] A universal ball head hook, comprising a ball head and a hook body, wherein the ball head is located at one end of the hook body;

[0015] The ball head is arranged between the pressing block and the elastic expansion ring and can rotate in the nail cap, and the elastic expansion ring can limit the ball head from falling out of the nail cap.

[0016] A rotation groove is provided on the inner wall of the elastic expansion ring. The rotation groove is a partial spherical surface and can fit with the surface of the ball head.

[0017] The inner wall of the elastic expansion ring also includes a cylindrical surface, and the cylindrical surface is connected to the lower edge of the rotating groove.

[0018] A clamping groove is arranged on the inner wall of the through hole, and the outer ring of the elastic expansion ring is clamped in the clamping groove.

[0019] The outer ring of the elastic expansion ring is provided with a plurality of notches at intervals.

[0020] The notch is rectangular or sawtooth-shaped.

[0021] The elastic expansion ring is made of Ti-Ni alloy.

[0022] The pressing block is annular, and two positioning grooves are symmetrically arranged on the outer wall of the pressing block. The positioning grooves cooperate with two symmetrical protrusions formed on the inner wall of the through hole to prevent the pressing block from falling off the nail cap.

[0023] The universal ball head hook also includes a neck, which connects the ball head and the hook body, and the outer diameter of the neck is smaller than the outer diameter of the ball head.

[0024] An inner plum blossom hole, an inner hexagonal hole, an inner square hole or a star-shaped hole is arranged at one end of the ball head away from the hook body.

[0025] An inner thread is arranged at one end of the inner wall of the through hole away from the universal ball head hook.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The invention provides a spinal bone hook, wherein the ball head of the universal ball head hook is arranged between the pressing block and the elastic expansion ring and can rotate in the nail cap, so the direction between the nail cap and the hook body is adjustable. When placing the bone hook, the hook body can find the best installation position in the appropriate orientation to hook the vertebral body and adhere to the vertebral body to the greatest extent. There is no need to consider that the excessive deviation of the nail cap of the bone hook will affect the placement of the rod. The grip is firm and there is no need to remove a lot of bone. Once the hook body hooks the vertebral body, the bending of the orthopedic rod is reduced to a certain extent due to the mobility of the nail cap, which provides a variety of possibilities and simplicity for the operation. The large swing angle installation of the bone hook body achieves the function of an offset hook, realizes the multi-purpose of the bone hook, simplifies the warehouse preparation and inventory, and increases practicality and creativity. Installing the bone hook not only greatly reduces the occurrence of stress concentration problems in the hook body itself, but also makes it difficult for the hook body to shift or fall out during the placement and rotation of the rod. It can be implanted in vertebrae that cannot be fixed with nails due to severe vertebral deformity. For the entire system, after adding the bone hook, the force points of the entire system are increased, and the stress is more dispersed and uniform. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a front view of the spinal bone hook of the present invention;

[0029] Figure 2 yes Figure 1 A schematic diagram of the enlarged structure of part A;

[0030] Figure 3 It is a schematic structural diagram of the universal ball head hook in the present invention;

[0031] Figure 4 It is a schematic diagram of the structure of the elastic expansion ring in the present invention;

[0032] Figure 5 It is an exploded view of the spinal bone hook of the present invention.

[0033] in:

[0034] 1 Nail cap 2 Pressure block

[0035] 3 Universal ball head hook 4 Elastic expansion ring

[0036] 11 Card slot 12 Through hole

[0037] 13 U-shaped notch 14 groove

[0038] 21 U-shaped notch 22 positioning groove

[0039] 31 ball head 32 hook body

[0040] 33 inner plum blossom hole 34 neck

[0041] 41 Rotation slot 42 Notch. DETAILED DESCRIPTION

[0042] The following is a detailed description of a spinal bone hook of the present invention in conjunction with the accompanying drawings and embodiments:

[0043] like Figures 1 to 5 As shown, this embodiment provides a spinal bone hook, including a nail cap 1, a pressing block 2, an elastic expansion ring 4 and a universal ball head hook 3.

[0044] like Figure 1 As shown, the nail cap 1 is provided with a through hole 12 along the axis, the pressing block 2 is arranged in the through hole 12 , and the elastic expansion ring 4 is a non-closed ring with an opening arranged in the through hole 12 and is located below the pressing block 2 .

[0045] The universal ball head hook 3 includes a ball head 31 and a hook body 32 , wherein the ball head 31 is located above the hook body 32 ; the universal ball head hook 3 also includes a neck 34 , which connects the ball head 31 and the hook body 32 , and the outer diameter of the neck 34 is smaller than the outer diameter of the ball head 31 .

[0046] The ball head 31 is disposed between the pressing block 2 and the elastic expansion ring 4 and can rotate in the nail cap 1 . The elastic expansion ring 4 can prevent the ball head 31 from escaping from the nail cap 1 .

[0047] The ball head 31 realizes the universal function, and the hook body 32 realizes the expected surgical purpose. The structural form of the hook body 32, such as the opening specification and the width of the hook body, can be designed in a variety of ways according to clinical needs. The end of the ball head 31 away from the hook body 32 is provided with an inner plum blossom hole 33, which cooperates with the surgical tool, and the surgical tool is inserted into the inner plum blossom hole 33 to realize the rotation of the universal ball head hook 3. In this embodiment, the surgical tool that cooperates with the inner plum blossom hole 33 is a nailer or a locking wrench. The hole on the ball head 31 that cooperates with the surgical tool can also be an inner hexagonal hole, an inner square hole or a star-shaped hole.

[0048] In this embodiment, if Figure 2-Figure 4 As shown, a slot 11 is provided on the inner wall of the through hole 12, and the outer ring of the elastic expansion ring 4 is clamped in the slot 11, so as to fix the elastic expansion ring 4 and prevent the universal ball head hook 3 from escaping from the nail cap 1 from one side of the elastic expansion ring 4.

[0049] Two symmetrical protrusions are formed on the inner wall of the through hole 12. The pressure block 2 is annular. Two positioning grooves 22 are symmetrically arranged on the outer wall of the pressure block 2. The two protrusions correspond to the two positioning grooves 22 one by one. The protrusions extend into the positioning grooves 22. The protrusions can limit the pressure block 2 in the through hole 12, thereby limiting the axial movement range of the universal ball head hook 3 in the through hole 12.

[0050] In this embodiment, a rotation groove 41 is formed on the inner wall of the elastic expansion ring 4 . The rotation groove 41 is a partial spherical surface and can fit with the surface of the ball head 31 .

[0051] The inner wall of the elastic expansion ring 4 also includes a cylindrical surface, which is connected to the lower edge of the rotating groove 41. The elastic expansion ring 4 of this structure can provide good support for the universal ball head hook 3 and can effectively prevent the inner ring of the elastic expansion ring 4 from deforming.

[0052] The outer ring of the elastic expansion ring 4 is provided with a plurality of notches 42 at intervals. The notches 42 are rectangular or sawtooth-shaped. The notches 42 are conducive to the stress deformation of the elastic expansion ring 4 and facilitate operation.

[0053] In this embodiment, the elastic expansion ring 4 is made of Ti-Ni alloy. According to specific requirements, the elastic expansion ring 4 can be made of other materials.

[0054] like Figure 5 As shown, an inner thread is provided at one end of the inner wall of the through hole 12 away from the universal ball head hook 3 .

[0055] Two U-shaped notches 13 and two symmetrically arranged grooves 14 are symmetrically arranged on the side wall of the nail cap 1, and the U-shaped notches 13 and the grooves 14 are alternately arranged.

[0056] Two U-shaped notches 21 are symmetrically formed on the side wall of the pressing block 2 , and the U-shaped notches 21 and the positioning grooves 22 are alternately arranged.

[0057] The U-shaped notch 21 corresponds to the U-shaped notch 13 one by one, and the edges are aligned with each other. The positions of the positioning groove 22 and the groove 14 correspond to each other one by one and are located on the same straight line.

[0058] When the pressing block 2 is installed inside the nail cap 1, it is only necessary to protrude the portion of the nail cap 1 corresponding to the groove 14 toward the inside of the nail cap 1 to form a protrusion that extends into the positioning groove 22, so that the pressing block 2 can be installed. In this embodiment, the protrusion size is smaller than the inner size of the positioning groove 22, and the pressing block 2 can be moved in the axial direction of the through hole 12, so when the universal ball head hook 3 rotates, it is prevented from being stuck by the pressing block 2, and the hook body 32 can be ensured to rotate smoothly during use, which is convenient for use.

[0059] In this embodiment, the inner diameter of the light hole of the through hole 12 is not less than the diameter of the ball head 31 .

[0060] The assembly method of the spinal bone hook of the present invention:

[0061] During assembly, firstly, the elastic expansion ring 4 is clamped in the neck 34 of the universal ball head hook 3 through the opening, and the ball head 31 of the universal ball head hook 3 is extended into the through hole 12 from the lower part of the nail cap 1, and then the diameter of the elastic expansion ring 4 is reduced, and the outer ring of the elastic expansion ring 4 is clamped into the clamping groove 11 of the nail cap 1, and then the universal ball head hook 3 is placed in the rotation groove 41 of the elastic expansion ring 4. The pressing block 2 is installed from the upper part of the nail cap 1, and when the positioning groove 22 is opposite to the grooves 14 on both sides, the inner wall of the through hole 12 corresponding to the groove 14 is formed into a bulge inward by external force, so that the pressing block 2 is restricted by the bulge, and the pressing block 2 and the elastic expansion ring 4 work together to restrict the ball head 31 in the nail cap 1. Since the ball head 31 matches the rotation groove 41 of the elastic expansion ring 4, the universal ball head hook 3 can rotate and swing at any angle within a certain area, and can realize the universal function. The surgical process makes it easier to install the bone hook and makes the system's resetting, lifting and connecting rod insertion operations quick and convenient.

[0062] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention shall fall within the protection scope and disclosure scope of the present invention.

Claims

1. A spinal bone hook, characterized in that: include: A nail cap (1) having a through hole (12) arranged along its axis; A pressing block (2) arranged in the through hole (12); An elastic expansion ring (4), which is a non-closed ring with an opening and is arranged in the through hole (12) and is located below the pressing block (2); A universal ball head hook (3), comprising a ball head (31) and a hook body (32), wherein the ball head (31) is located at one end of the hook body (32); The ball head (31) is arranged between the pressing block (2) and the elastic expansion ring (4) and is capable of rotating inside the nail cap (1); the elastic expansion ring (4) is capable of preventing the ball head (31) from falling out of the nail cap (1); A rotation groove (41) is provided on the inner wall of the elastic expansion ring (4), and the rotation groove (41) is a partial spherical surface and can fit with the surface of the ball head (31); The inner wall of the elastic expansion ring (4) further comprises a cylindrical surface, and the cylindrical surface is connected to the lower edge of the rotating groove (41); The outer ring of the elastic expansion ring (4) is provided with a plurality of notches (42) at intervals.

2. The spinal bone hook according to claim 1, characterized in that: A clamping groove (11) is provided on the inner wall of the through hole (12), and the outer ring of the elastic expansion ring (4) is clamped in the clamping groove (11).

3. The spinal bone hook according to claim 1, characterized in that: The notch (42) is rectangular or sawtooth-shaped.

4. The spinal bone hook according to claim 1, characterized in that: The pressing block (2) is annular in shape, and two positioning grooves (22) are symmetrically arranged on the outer wall of the pressing block (2). The positioning grooves (22) cooperate with two symmetrical protrusions formed on the inner wall of the through hole (12) to prevent the pressing block (2) from falling off the nail cap (1).

5. The spinal bone hook according to claim 1, characterized in that: The universal ball head hook (3) further comprises a neck (34), wherein the neck (34) connects the ball head (31) and the hook body (32), and the outer diameter of the neck (34) is smaller than the outer diameter of the ball head (31).

6. The spinal bone hook according to claim 1, characterized in that: An end of the ball head (31) away from the hook body (32) is provided with an inner plum blossom hole (33), an inner hexagonal hole, an inner square hole or a star-shaped hole.

7. The spinal bone hook according to claim 1, characterized in that: An inner thread is provided at one end of the inner wall of the through hole (12) away from the universal ball head hook (3).

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