CN115252236A

CN115252236A - Cervical vertebra embedded intervertebral fusion cage

Info

Publication number: CN115252236A
Application number: CN202211037707.0A
Authority: CN
Inventors: 蒋伟宇
Original assignee: Individual
Current assignee: Ningbo No 6 Hospital
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2022-11-01

Abstract

The invention relates to an embedded intervertebral fusion cage for cervical vertebra, which comprises: the fusion cage comprises a fusion cage body, a first fusion cage body and a second fusion cage body, wherein the fusion cage body is provided with a first fusion surface and a second fusion surface which are opposite in the vertical direction, and a bone grafting cavity which penetrates from the first fusion surface to the second fusion surface; and at least one of the first fusion surface and the second fusion surface is provided with a limit convex part which protrudes upwards or downwards relative to the corresponding first fusion surface or second fusion surface. Because the first fusion face or the second fusion face of the fusion cage body are provided with the limiting convex parts which are formed by upwards or downwards protruding, after the fusion cage body is embedded between the upper vertebral body and the lower vertebral body, the limiting convex parts can play a better limiting role, the problem of left-right displacement or backward displacement of the fusion cage body can be avoided, the stability of the fusion cage after being implanted is improved, and the fusion effect is ensured.

Description

Cervical vertebra embedded intervertebral fusion cage

Technical Field

The invention relates to the technical field of medical instruments, in particular to an embedded intervertebral fusion cage for cervical vertebra bodies.

Background

Cervical spondylopathy is common bone disease, cervical spondylopathy such as spinal cord type, nerve root type, at present, anterior cervical intervertebral disc excision interbody bone grafting fusion (ACDF), be the commonly used art formula of operation treatment cervical intervertebral disc disease, this operation is through the cervical intervertebral disc of less operation incision excision degeneration, implant cervical vertebra interbody fusion ware, relieve the oppression of outstanding intervertebral disc to spinal cord and nerve root, the anterior fixed operation segment of way at cervical vertebra sequence before combining again, prevent to plant the back of bone or fusion ware, dystopy and subside, keep cervical vertebra sequence normal height and physiology crookedness, improve operation fusion rate and operation segment stability, patient's focus can effectively be got rid of to this art formula, resume patient's normal intervertebral height and physiology crookedness. Although the ACDF operation type can effectively relieve the pain of a patient and recover the normal physiological curvature of the cervical vertebra of the patient, the situation that the implantation position is not ideal, the postoperative fusion effect is not good, the product slips or is separated, the product collapses and the like often occurs due to the influence of factors such as product design and the like, so that the operation fails; particularly for the serious condition of the hyperosteogeny at the back edge of the vertebral body, the ACDF operation is difficult to completely remove and reduce the pressure, and the operation is forced to be changed into a secondary complete removal operation of the cervical vertebral body, thereby increasing the operation trauma.

Therefore, the Chinese utility model patent with the application number of CN201721526269.9 (the publication number is CN 208065304U) discloses a cervical vertebra interbody fusion cage, which comprises a fusion cage body consisting of a hollow frame, wherein a bone grafting cavity and a developing pin are arranged on the body, a plurality of rows of parallel anti-skid fixing teeth are arranged on the upper surface and the lower surface of the body, the sagittal plane profile of the body is in a wedge shape with a high front part and a low back part, and the side wall is provided with at least two side windows which are arranged in a high front part and a low back part.

However, the above mentioned patent cervical interbody fusion cage has a certain disadvantage, firstly, for the case of obvious hyperosteogeny at the rear edge of the vertebral body, the end plate part of the vertebral body needs to penetrate through, and the groove is opened on the vertebral body to remove the hyperosteogeny part between the vertebrae, if the above mentioned interbody fusion cage is still used, the problems of the displacement and sinking of the fusion cage will inevitably occur due to the loss of the end plate part of the vertebral body, especially for the patient with osteoporosis. Secondly, although the interbody fusion cage adopts the side windows with different sizes, the contact area between the bone filler and the surrounding tissues is increased to a certain extent, and the purpose of promoting fusion is realized, the problem of reducing the rigidity of the product is caused by slotting the interbody fusion cage, and the bearing capacity of the product is limited.

Disclosure of Invention

The invention aims to solve the first technical problem and provides a cervical vertebra centrum embedded intervertebral fusion cage which can effectively reduce the displacement problem of the fusion cage aiming at the current situation of the prior art.

The second technical problem to be solved by the invention is to provide the cervical vertebra centrum embedded intervertebral fusion cage which can effectively increase the contact area of bone filler and surrounding tissues and ensure the fusion effect aiming at the current situation of the prior art.

The technical scheme adopted by the invention for solving the first technical problem is as follows: an embedded intervertebral fusion cage for cervical vertebral bodies, comprising:

the fusion cage comprises a fusion cage body and a bone grafting device, wherein the fusion cage body is provided with a first fusion surface and a second fusion surface which are opposite in the vertical direction, and a bone grafting cavity which penetrates from the first fusion surface to the second fusion surface;

at least one of the first fusion surface and the second fusion surface is provided with a limit convex part which protrudes upwards or downwards relative to the corresponding first fusion surface or second fusion surface.

The technical scheme adopted by the invention for solving the second technical problem is as follows: the limiting convex part is flat and is provided with a bone grafting space which is communicated with the left and the right, and the bone grafting space is communicated with the bone grafting cavity. Preferably, the bone grafting space is positioned right above the bone grafting cavity so as to be convenient for filling bone materials and forming a bone grafting layer.

Set up corresponding bone grafting space on above-mentioned spacing convex part and can form a complete bone grafting cavity that can extend to centrum end plate part with the bone grafting chamber of fusing the ware body, from this, the bone grafting layer that forms after filling the sclerotin material not only can fuse with upper and lower centrum end plate in the upper and lower direction, can also fuse with the left and right sides of the fluting part of centrum, increased and fused the area, realized promoting to fuse the purpose in the at utmost, guaranteed to fuse the effect.

The width of the limiting convex part (which can be understood as the width of the bone grafting space on the limiting convex part in the left-right direction) can be in various specifications, and can be specifically selected according to the size of the groove required on the vertebral body end plate, and preferably, the depth of the bone grafting space in the left-right direction is smaller than the size of the bone grafting cavity in the left-right direction.

In order to realize the fixed connection with the external fixing plate, at least the front side wall surface of the limiting convex part is a vertical plane and is provided with a screw hole for connecting with an external screw.

As an improvement, the front side wall face and the rear side wall of the limiting convex part are both vertical planes.

In order to adapt to the condition that one or two of the upper vertebral body end plate and the lower vertebral body end plate need to be grooved to remove hyperosteogeny, the first fusion surface and the second fusion surface of the fusion cage body are respectively provided with the limiting convex part.

In order to further solve the problem of backward movement of the fusion cage, the distance between the first fusion surface and the second fusion surface of the fusion cage body is gradually reduced from front to back, so that the fusion cage body is wedge-shaped as a whole.

Preferably, the first and/or second fusion surfaces of the fusion body are at an angle α to the horizontal, wherein 3 ° < α < 5 °.

For convenience of processing and cost saving, the fusion cage body and the limiting convex part are integrated.

Compared with the prior art, the invention has the advantages that: because the first fusion face or the second fusion face of the fusion cage body are provided with the limiting convex parts which are formed by upwards or downwards protruding, after the fusion cage body is embedded between the upper vertebral body and the lower vertebral body, the limiting convex parts can play a better limiting role, the problem of left-right displacement or backward displacement of the fusion cage body can be avoided, the stability of the fusion cage after being implanted is improved, and the fusion effect is ensured. In the preferred scheme, the bone grafting space which is communicated with and right opposite to the bone grafting cavity is formed in the limiting convex part, the bone grafting space and the bone grafting cavity of the fusion cage body can form a complete bone grafting cavity which can extend to the vertebral body end plate part, therefore, a bone grafting layer formed after the fusion cage is filled with bone materials can be fused with the upper vertebral body end plate and the lower vertebral body end plate in the up-down direction, and can be fused with the left side and the right side of the grooved part of the vertebral body end plate, the fusion area is increased, the purpose of promoting fusion is achieved to the greatest extent, and the fusion effect is ensured.

Drawings

FIG. 1 is a schematic perspective view of a human spine;

FIG. 2 is a perspective view of a portion of a human spine according to an embodiment of the present invention;

FIG. 3 is an exploded view of FIG. 2;

FIG. 4 is a perspective view of an intervertebral cage of an embodiment of the present invention mounted to a spine by a fixation plate;

FIG. 5 is an exploded view of FIG. 4;

FIG. 6 is a perspective view of an intervertebral cage according to an embodiment of the invention;

FIG. 7 is a perspective view of an intervertebral cage according to another embodiment of the present disclosure;

fig. 8 is a right side view of fig. 7.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

Directional terms such as "front," "rear," "upper," "lower," "left," "right," "side," "top," "bottom," and the like are used in the description and claims of the present invention to describe various example structural portions and elements of the invention, but are used herein for convenience of description only and are to be determined based on the example orientations shown in the drawings. Because the disclosed embodiments of the present invention may be oriented in different directions, the directional terms are used for descriptive purposes and are not to be construed as limiting, e.g., "upper" and "lower" are not necessarily limited to directions opposite or coincident with the direction of gravity.

Referring to fig. 1 to 3, there is shown a structure of a human spinal column in which two vertebral bodies adjacent to each other up and down have intervertebral discs 10c, and when the intervertebral discs 10c are protruded, it is necessary to remove the corresponding protruded parts of the intervertebral discs from the front and then to insert an intervertebral cage so as to relieve the pressure of the protruded intervertebral discs 10c on the spinal cord and nerve roots. When severe hyperosteogeny or ossification of a posterior longitudinal ligament occurs at the posterior lower edge 10a of the upper vertebral body and the posterior upper edge 10B of the lower vertebral body (such as the positions A and B in fig. 3), the end plate part of the vertebral body needs to penetrate through the slot (such as the dotted line part in fig. 3) so as to safely and completely remove the hyperosteogeny part between the vertebrae, and the problems of posterior movement and subsidence of the fusion cage inevitably occur due to the deletion of the end plate part of the vertebral body, especially for osteoporosis patients.

For the serious condition of the hyperosteogeny at the back edge of the vertebral body, the conventional ACDF operation mode is difficult to completely remove and reduce the pressure, and the operation is forced to be changed into a secondary total removal operation of the cervical vertebral body; or the posterior margin of the vertebral body is subjected to hyperosteogeny removal through the vertebral body slotting, however, the existing cervical vertebra intervertebral fusion cage can not fill the bone defect after the vertebral body slotting, and the damage of the end plate after the vertebral body slotting increases the sinking risk of the common fusion cage, so as to avoid the situation, referring to fig. 4-8, the invention provides the cervical vertebra intervertebral embedded fusion cage, which comprises a fusion cage body 20 and a limit convex part 24 arranged on the fusion cage body 20, wherein the fusion cage body 20 and the limit convex part 24 are designed into a whole, and are generally made of PEEK or hydroxyapatite and other bone substitute materials.

Referring to fig. 6, the fusion cage body 20 is flat as a whole, and has a first fusion surface 21 and a second fusion surface 22 opposite to each other in the vertical direction, wherein a bone grafting cavity 23 penetrating from the first fusion surface 21 to the second fusion surface 22 is further opened in a central region of the fusion cage body 20. The bone graft chamber 23 prevents bone filler to promote fusion with the upper and lower vertebral bodies 10 b. The distance between the first fusion surface 21 and the second fusion surface 22 of the cage body 20 is gradually decreased from the front to the rear, so that the cage body 20 is wedge-shaped as a whole. Specifically, the angle between the first fusion surface 21 and/or the second fusion surface 22 of the fusion cage body 20 and the horizontal plane is α, wherein 3 ° < α < 5 °, e.g., the angle α between the first fusion surface 21 of the upper portion of the fusion cage body 20 and the horizontal plane is shown in fig. 8.

The limit projections 24 may have one or two, thereby allowing the cage to have various specifications. Referring to fig. 7 and 8, when there is one limiting protrusion 24, the limiting protrusion 24 may be disposed on the first fusion surface 21 or the second fusion surface 22 of the fusion device body 20. Referring to fig. 6, when there are two limiting protrusions 24, the two limiting protrusions 24 may be respectively disposed on the first fusing surface 21 and the second fusing surface 22 of the fusion cage body 20, wherein one limiting protrusion 24 protrudes upward from the first fusing surface 21, and the other limiting protrusion 24 protrudes downward from the second fusing surface 22.

With continued reference to fig. 6, the limiting convex portion 24 is also flat and has a bone grafting space 240 penetrating from left to right, wherein the bone grafting space 240 is opposite to and communicated with the bone grafting cavity 23 in the vertical direction. The bone grafting space 240 on the limiting convex part 24 can form a complete bone grafting cavity which can extend to the vertebral body end plate part with the bone grafting cavity 23 of the fusion cage body 20, therefore, the bone grafting layer formed after filling the bone material can be fused with the upper vertebral body end plate and the lower vertebral body end plate in the upper and lower directions, and can be fused with the left side and the right side of the slotting part of the vertebral body end plate, the fusion area is increased, the purpose of promoting fusion is realized to the maximum extent, and the fusion effect is ensured. Particularly, the fusion cage of the embodiment can effectively fill the bone defect after the grooving of the vertebral body, disperse the stress of the residual end plate, increase the contact area of the bone filler of the fusion cage and the surrounding tissues, ensure the fusion effect and reduce the sinking risk of the fusion cage.

In this embodiment, the width of the limit protrusion 24 (which may also be understood as the depth of the bone grafting space 240 on the limit protrusion 24 in the left-right direction) may have various specifications, and may be specifically selected according to the size of the opening required on the vertebral body endplate. Generally, the depth of the bone grafting space 240 in the left-right direction is smaller than the size of the bone grafting cavity 23 in the left-right direction.

After the fusion cage is embedded between the upper and lower vertebral bodies, it is fixed by an external fixing plate 31, and the fixing plate 31 can cover the corresponding portions of the upper and lower vertebral bodies and be fastened by screws. Specifically, the upper and lower portions of the fixing plate 31 are respectively provided with a second connecting hole 311 through which a screw passes.

The front side wall and the rear side wall of the limit convex portion 24 are both vertical planes, and a screw hole 241 for connecting with the external screw 32 is provided on the front side wall of the limit convex portion 24. The middle portion of the fixing plate 31 is provided with a first connection hole 310 at a region corresponding to the screw hole 241 of the limit projection 24. When the fusion cage is installed, the screw passes through the first connection hole 310 and is connected to the screw hole 241 of the fusion cage limiting convex portion 24, so that the fixing plate 31 and the fusion cage are fixed.

The fusion cage of the embodiment can be applied to at least the following two lesion surgery situations in the practical application process.

Aiming at the focus of the protrusion of the intervertebral disc 10c, when the focus of the protrusion of the intervertebral disc 10c is removed, as shown in fig. 5, the incision 11a for placing the fusion cage body is formed by removing the protrusion of the intervertebral disc on the intervertebral disc 10c, the caulking groove 11b for embedding the limit convex part 24 of the fusion cage therein is arranged on the corresponding vertebral body end plate, and the caulking groove 11b is only arranged at the front part of the vertebral body and does not need to penetrate backwards to the back side of the vertebral body. After the fusion cage body 20 is embedded into the incision 11a between the upper and lower vertebral bodies, the limiting convex part 24 is embedded in the embedding groove 11b, so that a better limiting effect can be achieved, the problems of backward movement and left-right movement of the fusion cage body 20 are avoided, the stability of the fusion cage after being implanted is improved, and the fusion effect is ensured. On the basis, the bone material filled in the bone grafting space 240 on the limiting convex part 24 can be fused with the left side and the right side of the slotted part of the vertebral body end plate, so that the fusion area is increased, and the fusion effect is improved.

For the focus of the hyperosteogeny of the intervertebral disc 10c, a front-back through slot (as shown by a dotted line frame in fig. 3) needs to be opened on the corresponding vertebral body to remove the hyperosteogeny part, so that after the fusion cage body 20 is embedded between the upper and lower vertebral bodies, the limit convex part 24 is also correspondingly embedded in the slot of the vertebral body and is attached to the left and right side walls of the slot. The bone grafting space 240 on the limiting convex part 24 can form a complete bone grafting cavity which can extend to the vertebral body end plate part with the bone grafting cavity 23 of the fusion cage body 20, therefore, the bone grafting layer formed after filling the bone material can be fused with the upper vertebral body end plate and the lower vertebral body end plate in the upper and lower directions, and can be fused with the left side and the right side of the slotting part of the vertebral body end plate, the fusion area is increased, the purpose of promoting fusion is realized to the maximum extent, and the fusion effect is ensured. Since the fusion cage is fixed to the fixing plate 31 by screws, there is no problem of backward movement.

Claims

1. An embedded intervertebral fusion cage for cervical vertebral bodies, comprising:

a fusion cage body (20) having a first fusion surface (21) and a second fusion surface (22) which face each other in the vertical direction, and a bone grafting cavity (23) which penetrates from the first fusion surface (21) to the second fusion surface (22);

the method is characterized in that: at least one of the first fusion surface (21) and the second fusion surface (22) is provided with a limit convex part (24) which is convex upwards or downwards relative to the corresponding first fusion surface (21) or second fusion surface (22).

2. The cervical vertebral body-embedded intervertebral fusion cage of claim 1, wherein: the limiting convex part (24) is flat and is provided with a bone grafting space (240) which is communicated with the left and the right, and the bone grafting space (240) is communicated with the bone grafting cavity (23).

3. The cervical vertebral body-embedded intervertebral fusion cage of claim 2, wherein: the depth of the bone grafting space (240) in the left-right direction is smaller than the size of the bone grafting cavity (23) in the left-right direction.

4. The cervical vertebral body-embedded intervertebral fusion cage of claim 3, wherein: at least the front side wall surface of the limiting convex part (24) is a vertical plane, and is provided with a screw hole (241) used for being connected with an external screw.

5. The cervical vertebral body-embedded intervertebral fusion cage of claim 1, wherein: the front side wall surface and the rear side wall of the limiting convex part (24) are vertical planes.

6. The cervical vertebral body embedded intervertebral fusion cage according to any one of claims 1 to 5, wherein: the first fusion surface (21) and the second fusion surface (22) of the fusion device body (20) are both provided with the limiting convex part (24).

7. The embedded intervertebral fusion cage of cervical vertebra according to any one of claims 1 to 5, characterized in that: the distance between the first fusion surface (21) and the second fusion surface (22) of the fusion device body (20) is gradually reduced from front to back, so that the fusion device body (20) is wedge-shaped as a whole.

8. The cervical vertebral body-embedded intervertebral fusion cage of claim 7, wherein: the included angle between the first fusion surface (21) and/or the second fusion surface (22) of the fusion device body (20) and the horizontal plane is alpha, wherein alpha is more than 3 degrees and less than 5 degrees.

9. The embedded intervertebral fusion cage of cervical vertebra according to any one of claims 1 to 5, characterized in that: the fusion cage body (20) and the limiting convex part (24) are integrated.