CN112402071A

CN112402071A - Intervertebral fusion cage

Info

Publication number: CN112402071A
Application number: CN201910785573.2A
Authority: CN
Inventors: 文晓宇; 徐凯; 张靖; 马学为; 孙陆; 刘昊
Original assignee: Beijing Zhisu Health Technology Co ltd
Current assignee: Beijing Zhisu Health Technology Co ltd
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2021-02-26

Abstract

The invention discloses an intervertebral fusion cage, and relates to the technical field of medical instruments. One embodiment of the intervertebral cage comprises: a support structure and a void structure; wherein, bearing structure includes: the upper end of the supporting column is connected with the side edge of the upper supporting surface, and the lower end of the supporting column is connected with the side edge of the lower supporting surface; the pore structure is arranged in a cavity formed by the upper supporting surface, the lower supporting surface and the supporting columns; the center of the pore structure is provided with a through hole for accommodating the spine. The embodiment can greatly reduce the volume of the fusion cage, improve the porosity of the fusion cage and have better bone fusion effect.

Description

Intervertebral fusion cage

Technical Field

The invention relates to the technical field of medical instruments, in particular to an interbody fusion cage.

Background

The interbody fusion cage has the functions of supporting, load sharing and the like, and can better recover the intervertebral space height and the physiological curvature of the spine.

The fusion cage in the prior art has at least the following problems:

(1) the existing fusion cage is mostly composed of a solid frame structure and a through hole structure. The solid support mostly adopts a solid axial support surface, so that the size of the fusion cage is greatly occupied, the porosity of the fusion cage is too small, and the bone fusion effect is influenced;

(2) in the prior art, the fusion cage is easy to cause the problems of loosening and shifting in the later period of implantation;

(3) the existing pore structure is mostly formed by a regular space regular octahedral structure and is mostly distributed on the upper surface, the lower surface or the left side and the right side of the interbody fusion cage, and the porosity cannot be customized individually.

Disclosure of Invention

In view of this, the embodiment of the invention provides an intervertebral fusion cage, which can greatly reduce the volume of the fusion cage, improve the porosity of the fusion cage, and has a better bone fusion effect.

To achieve the above object, according to an aspect of an embodiment of the present invention, there is provided an intervertebral cage including: a support structure and a void structure; wherein the content of the first and second substances,

the support structure includes: the upper end of the supporting column is connected with the side edge of the upper supporting surface, and the lower end of the supporting column is connected with the side edge of the lower supporting surface;

the pore structure is arranged in a cavity formed by the upper supporting surface, the lower supporting surface and the supporting columns; the center of the pore structure is provided with a through hole for accommodating the spine.

Optionally, the support structure further comprises: the upper end of the rear supporting column is connected with the rear side of the upper supporting surface, and the lower end of the rear supporting column is connected with the rear side of the lower supporting surface; the support column sets up in the left place ahead and the right place ahead of last holding surface and lower holding surface.

Optionally, an instrument hole is provided in the rear support strut.

Optionally, an instrument slot is provided on the rear support strut, and the instrument hole is provided in the instrument slot.

Optionally, the upper and lower support surfaces are provided with protrusions.

Optionally, a through hole is provided in the pore structure.

Optionally, the aperture of the through hole is 100 μm to 800 μm, and the distance between two adjacent through holes is 100 μm to 1500 μm.

Optionally, the support structure has a rear width greater than a front width; and/or the height of the rear side of the support structure is greater than the height of the front side.

Optionally, the inclination angle of the interbody fusion cage is 0-7 °.

Optionally, the length of the interbody fusion cage is 11 mm-16 mm, the width is 11 mm-16 mm, the thickness is 3 mm-6 mm, and the height is 4 mm-12 mm.

One embodiment of the above invention has the following advantages or benefits: the adoption includes bearing surface, under bracing face and the bearing structure of support column, compares with adopting entity axial bearing surface among the prior art, can reduce greatly and fuse the ware volume, improves the porosity that fuses the ware, has better bone fusion effect. The protrusion parts are arranged on the upper and lower supporting surfaces, so that horizontal slippage can be prevented; the instrument hole is formed in the rear support column, so that the intervertebral fusion cage can be conveniently conveyed to an intervertebral designated position and fixed by matching with a conveying tool; through set up the through-hole on pore structure portion, be favorable to bone ingrowth and bone fusion.

Further effects of the above-mentioned non-conventional alternatives will be described below in connection with the embodiments.

Drawings

The drawings are included to provide a better understanding of the invention and are not to be construed as unduly limiting the invention. Wherein:

FIG. 1 is a front view of an intervertebral cage according to an embodiment of the invention;

FIG. 2 is a top schematic view of an intervertebral cage according to an embodiment of the invention;

FIG. 3 is a right side schematic view of an intervertebral cage according to an embodiment of the invention;

FIG. 4 is a rear view of an intervertebral cage according to some embodiments of the invention;

fig. 5 is a schematic rear view of an intervertebral cage according to further embodiments of the invention.

Detailed Description

Exemplary embodiments of the present invention are described below with reference to the accompanying drawings, in which various details of embodiments of the invention are included to assist understanding, and which are to be considered as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted in the following description for clarity and conciseness.

Fig. 1-5 illustrate, from various angles, a schematic view of an intervertebral cage according to an embodiment of the present invention, such as the intervertebral cage 100 according to an embodiment of the present invention shown in fig. 1-5, including: support structure 10 and void structure 20; wherein the support structure 10 comprises: the device comprises an upper supporting surface 11, a lower supporting surface 12 and a supporting column 13, wherein the upper end of the supporting column 13 is connected with the side edge of the upper supporting surface 11, and the lower end of the supporting column 13 is connected with the side edge of the lower supporting surface 12; the pore structure 20 is arranged in a cavity formed by the upper support surface 11, the lower support surface 12 and the support columns 13; the void structure 20 is centrally provided with a through-going hole 30 for receiving the spine. The pore structure also plays a supporting role, so that the maximization of the porosity of the interbody fusion cage is realized, and the two functions of elastic modulus matching and large porosity are considered. The adoption includes bearing surface, under bracing face and the bearing structure of support column, and bearing structure's elastic modulus is close people's bone elastic modulus, can avoid taking place stress and shelter from, compares with the adoption entity axial bearing surface among the prior art, can reduce greatly and fuse the ware volume, improves the porosity that fuses the ware, has better bone fusion effect.

In the practical application process, the cervical vertebra interbody fusion cage can be manufactured by adopting 3D printing, and the surface roughness of the material can be increased by adopting 3D printing. The product surface that 3D printed is unevenness, and the concave surface that forms of printing is favorable to the cell to adhere to, increases the cell adhesion area, easily bone fusion.

The structure of the supporting column 13 can be selectively set according to practical situations, such as a cylindrical or rectangular parallelepiped structure. The number of the support columns 13 can also be selectively set according to actual conditions, such as 2, 3, and the like. Optionally, the support structure 10 further comprises: a rear support pillar 15, the upper end of the rear support pillar 15 is connected with the rear side of the upper support surface 11, and the lower end is connected with the rear side of the lower support surface 12; the support columns 13 are provided in front left and right of the upper support surface 11 and the lower support surface 12. By adopting the structure, the volume of the interbody fusion cage can be greatly reduced while the support stability is ensured, the porosity of the interbody fusion cage is improved, and the bone fusion is convenient.

Optionally, an instrument hole 16 is provided in the rear support strut 15, see fig. 4. By providing instrument holes 16 in the posterior support column 15, it is advantageous to work with a delivery tool to deliver the interbody cage to the designated intervertebral location and secure the interbody cage. Further, an instrument slot 17 is formed on the rear support post 15, and an instrument hole 16 is formed in the instrument slot 17, see fig. 5. An instrument groove 17 is added outside the instrument hole 16, so that the clamp can clamp and fix the intervertebral fusion device to be fed into and taken out of an affected part conveniently. The shape of the instrument slot 17 can be selectively set according to the actual situation, for example, a square shape, a round shape, etc.

Optionally, the upper support surface 11 and the lower support surface 12 are provided with protrusions 14. The protrusion enables better fixation of the intersomatic cage between the vertebrae. The fusion cage in the prior art is not provided with a structure for increasing the friction coefficient, so that the problems of looseness and displacement in the later period of implantation are easily caused. The invention can prevent the intervertebral fusion device from horizontally sliding by arranging the protruding parts on the upper and lower supporting surfaces.

The pore structure part 20 can be filled with different lattices, has low cost, does not need to be implanted into human bones, and reduces trauma. The through hole structure of the existing fusion cage mostly adopts an upper surface main through hole and a lower surface main through hole or a pore structure, and the elastic modulus of the fusion cage is influenced by the overlarge size of the main through hole. In an alternative embodiment of the invention, a through hole 21 is provided in the void structure 20. By providing the through hole 21 in the porous structure portion 20, the through hole 21 communicates with the outside, which is advantageous for bone ingrowth and bone fusion. The shape of the through hole may be a regular-shaped hole such as a circular hole, a square hole, a rectangular hole, a triangular hole, a polygonal hole, an elliptical hole, or an irregular-shaped hole. The size of the through holes, such as the aperture and the distance between two adjacent through holes, can be selectively set according to the actual situation, and optionally, the aperture of the through hole is 100 μm to 800 μm, and the distance between two adjacent through holes is 100 μm to 1500 μm. By adjusting the number and size of the through holes, a customized design of porosity can be achieved.

The transition part between each side of the supporting structure part is in a circular arc shape, so that the shape of the transition part can be matched with the upper surface and the lower surface of the cervical vertebra joint. Optionally, the support structure has a rear width greater than a front width, see fig. 2. The width of the back side is larger than that of the front side based on the design of the shape of the cervical vertebra, and the operation convenience of the implantation operation can be improved.

Optionally, the support structure has a rear height greater than a front height. The height of the back side is greater than that of the front side, the design is based on the individual difference of the cervical vertebra structures of different patients, an included angle formed between the upper supporting surface and the lower supporting surface is called as an inclined angle, and the intervertebral fusion cage with different height inclined angles can be customized according to different affected parts. Optionally, the inclination angle of the interbody fusion cage is 0-7 °.

The dimensions of the intervertebral cage, such as length, width, height and thickness, can be selectively set according to the actual situation. Optionally, the length of the interbody fusion cage is 11 mm-16 mm, the width is 11 mm-16 mm, the thickness is 3 mm-6 mm, and the height is 4 mm-12 mm. In this example, the length is a dimension in the front-rear direction, the width is a dimension in the left-right direction, and the height is a dimension in the up-down direction. The thickness is a dimension from the edge of the through-hole to the edge of the void structure portion.

Illustratively, the structural parameters of the intervertebral cage are as follows:

TABLE 1 structural parameters

Parameter(s)

L

θ

W

W_t

H

D

D_t

Numerical range

11-16mm

0-7°

11-16mm

3-6mm

4-12mm

100-800um

100-1500um

In the table, L is the interbody cage length, W is the interbody cage width, W_tThickness of the cage, height of the cage, angle theta, inclination angle of the cage, diameter of the through hole, and thickness D_tThe diameter of the rod is the distance between two adjacent through holes. By adopting the structure in the table 1, the porosity of the obtained porous interbody fusion cage structure is 5-90%.

The chemical composition of the porous interbody fusion cage material is shown in the following table:

at present, polyether ether ketone (PEEK) materials are mainly used in clinical application, however, PEEK does not have bioactivity as a manufacturing material of the fusion cage, real fusion with upper and lower bony endplate tissues can not be realized, most surfaces are covered by fibrous tissues and are easy to generate micro motion, the biomechanical stability between vertebral bodies is further influenced, and the stability of the whole structure can not be ensured. The embodiment shown in the table 2 of the invention adopts the titanium alloy intervertebral fusion device which has better biocompatibility and supporting strength. The compression rigidity of the porous intervertebral fusion device is close to the rigidity of human skeleton, the stress shielding effect is reduced, and the rigidity is 1000-100000N/mm.

According to the technical scheme of the embodiment of the invention, the supporting structure comprising the upper supporting surface, the lower supporting surface and the supporting columns is adopted, so that compared with the prior art in which the solid axial supporting surface is adopted, the size of the fusion cage can be greatly reduced, the porosity of the fusion cage is improved, and a better bone fusion effect is achieved. The protrusion parts are arranged on the upper and lower supporting surfaces, so that horizontal slippage can be prevented; the instrument hole is formed in the rear support column, so that the intervertebral fusion cage can be conveniently conveyed to an intervertebral designated position and fixed by matching with a conveying tool; through set up the through-hole on pore structure portion, be favorable to bone ingrowth and bone fusion.

The above-described embodiments should not be construed as limiting the scope of the invention. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions can occur, depending on design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An intervertebral cage, comprising: a support structure and a void structure; wherein the content of the first and second substances,

the pore structure is arranged in a cavity formed by the upper supporting surface, the lower supporting surface and the supporting column; the center of the pore structure is provided with a through hole for accommodating a vertebra.

2. The intersomatic cage of claim 1, wherein the support structure further comprises: the upper end of the rear supporting column is connected with the rear side of the upper supporting surface, and the lower end of the rear supporting column is connected with the rear side of the lower supporting surface; the support columns are arranged on the left front side and the right front side of the upper support surface and the lower support surface.

3. An intersomatic cage according to claim 2, characterized in that the rear support column is provided with an instrument hole.

4. An intersomatic cage according to claim 3, characterized in that the rear support column is provided with an instrument slot in which the instrument hole is provided.

5. An intersomatic cage according to claim 1, wherein the upper and lower support surfaces are provided with projections.

6. The intersomatic cage of claim 1, wherein the aperture structure is provided with a through hole therein.

7. The intersomatic cage according to claim 2, wherein the through-holes have a diameter of 100 μm to 800 μm and the distance between two adjacent through-holes is 100 μm to 1500 μm.

8. The intersomatic cage of claim 1, wherein the support structure has a posterior width greater than an anterior width; and/or the height of the rear side of the support structure is greater than the height of the front side.

9. The intersomatic cage according to claim 8, characterized in that the angle of inclination of the intersomatic cage is 0 to 7 °.

10. The intersomatic cage of claim 1, wherein the intersomatic cage has a length of 11mm to 16mm, a width of 11mm to 16mm, a thickness of 3mm to 6mm and a height of 4mm to 12 mm.