CN220141886U

CN220141886U - Intervertebral fusion device

Info

Publication number: CN220141886U
Application number: CN202321424273.XU
Authority: CN
Inventors: 王梓权; 林寿涵; 纪荣泉
Original assignee: Beijing Naton Medical Technology Holdings Co Ltd
Current assignee: Beijing Naton Medical Technology Holdings Co Ltd
Priority date: 2023-06-06
Filing date: 2023-06-06
Publication date: 2023-12-08
Anticipated expiration: 2033-06-06

Abstract

The utility model discloses an intervertebral fusion device, which belongs to the technical field of orthopedic implants and comprises an upper substrate, a lower substrate and a support piece positioned between the upper substrate and the lower substrate, wherein the support piece has elasticity, and comprises a first porous area, so that the elastic deformation proportion of the support piece is in the range of 10-40%. The elastic modulus of the intervertebral fusion device is equivalent to the elastic modulus of natural bones of a human body, the rigidity of the intervertebral fusion device is reduced, stress shielding is avoided, bone tissue ingrowth is facilitated, osseointegration is promoted, the fusion effect is ideal, the intervertebral fusion device can realize certain elastic deformation, proper stress stimulation can be provided for bone growth at a fusion position, bone growth is promoted, bone density is enhanced, the mechanical environment of a spine can be dealt with, and the service life of the intervertebral fusion device is prolonged.

Description

Intervertebral fusion device

Technical Field

The utility model relates to the technical field of orthopedic implants, in particular to an intervertebral fusion device.

Background

Spinal degenerative diseases gradually become common and frequently encountered diseases in clinic, and besides conservative treatment, intervertebral fusion devices are commonly implanted between vertebral bodies to maintain the stability of the vertebral bodies. Materials commonly used at present for preparing the interbody fusion cage include titanium alloy, PEEK (polyether ether ketone) and the like. However, the elastic modulus of the titanium alloy is far greater than that of natural bones of human bodies, and the difference can cause stress shielding, so that the problems of sinking, loosening and the like of the interbody fusion cage are caused. Although the mechanical property of PEEK material is closer to that of human bone than titanium alloy, the biological activity is not high, and the fusion effect is not ideal.

In addition, cage-type fusion cage (cage) on the market at present can not provide stress stimulation for bone growth basically, the wolff law indicates that the bone functions to bear mechanical strain of bone tissue during activity, the bone growth can be influenced by the mechanical stimulation to change the structure, and when the strain of the bone is 50-100 micro-strain and the stress is lower than 1-2MPa, the bone tissue is absorbed; when the strain of the bone is 1000-1500 micro-strain and the stress is higher than 20MPa, bone tissue grows; and when the strain of the bone is further higher than 3000 micro-strain and the stress is higher than 60MPa, the bone tissue is damaged. There is therefore a need for improvements to these existing problems.

Disclosure of Invention

The utility model aims to provide an intervertebral fusion device with ideal fusion effect.

In order to solve the technical problems, the utility model provides the following technical scheme:

an intervertebral cage comprising an upper substrate, a lower substrate, and a support member between the upper and lower substrates, the support member having elasticity, the support member comprising a first porous region such that the support member has an elastic deformation ratio in the range of 10-40%.

Further, the support further comprises a second porous region, wherein:

the pore size of the porous structure adopted by the first porous region is different from that of the porous structure adopted by the second porous region;

and/or the first porous region and the second porous region adopt different porous structures.

Further, the support member comprises an inner layer and an outer layer, the inner layer is the first porous region, the outer layer is the second porous region, and the pore diameter of a porous structure adopted by the first porous region is larger than that of a porous structure adopted by the second porous region;

or, the support member includes an inner layer, an outer layer, and an intermediate layer between the inner layer and the outer layer, wherein the intermediate layer is the first porous region, the inner layer and the outer layer are the second porous region, and the pore diameter of the porous structure adopted by the first porous region is larger than the pore diameter of the porous structure adopted by the second porous region.

Further, the upper substrate and the lower substrate are of split type design;

or, the upper base plate and the lower base plate are designed as a whole, and vertical connecting plates are arranged at the front ends of the upper base plate and the lower base plate.

Further, a holder interface piece is arranged at the rear end of the interbody fusion cage, the holder interface piece is embedded at the rear part of the support piece, and the height of the holder interface piece is smaller than the height between the upper base plate and the lower base plate;

and/or, the middle parts of the upper base plate and the lower base plate are respectively provided with a bone grafting window, and the middle part of the supporting piece is provided with a vertical bone grafting hole communicated with the bone grafting windows.

Further, the shape of the interbody fusion cage is horseshoe-shaped, U-shaped, bullet-shaped or kidney-shaped;

and/or, the material of the interbody fusion cage is titanium metal;

and/or the preparation mode of the interbody fusion cage is 3D printing technology;

and/or, the upper base plate and the lower base plate are respectively provided with transverse anti-withdrawal teeth;

and/or the porosity ranges of the porous structures adopted by the first porous region and the second porous region are 60% -95%;

and/or the modulus of elasticity of the interbody fusion cage is maintained in the range of 0.5-20 Gpa.

Further, the porous structure adopted by the first porous region is a spiral structure, and the rod diameter range of the spiral structure is 100-700 μm, wherein:

the spiral structure is an elastic single-spiral structure;

or the spiral structure is an elastic double-spiral structure;

alternatively, the spiral structure is an elastic multi-spiral structure, wherein the number of spirals is at least three;

alternatively, the helix structure comprises at least two elastic multiple helix structures arranged side by side, wherein the number of helices in a single elastic multiple helix structure is at least three.

Further, the porous structure adopted by the first porous region is a very small patch structure, and the wall thickness of the very small patch structure ranges from 100 μm to 700 μm, wherein:

the monomer of the minimum patch structure is of a split p structure;

alternatively, the monomer of the extremely small patch structure is a schwarz p structure;

or the monomer of the extremely small patch structure is a neovis structure;

or the monomer of the minimum patch structure is an lip structure;

alternatively, the monomer of the extremely small patch structure is a gyroid structure.

Further, the porous structure adopted by the first porous region is a woven structure or an elastic folding structure, and the rod diameter range of the woven structure or the elastic folding structure is 100-700 mu m;

or the porous structure adopted by the first porous region is a Thiessen polygonal structure, and the wall thickness range of the Thiessen polygonal structure is 100-700 mu m.

Further, the porous structure adopted by the second porous region is a negative poisson ratio structure, wherein:

the unit of the negative poisson ratio structure is in a windmill shape with four blades;

or, the units of the negative poisson ratio structure are I-shaped and are arranged in a transverse and vertical embedding manner;

alternatively, the cells of the negative poisson ratio structure are hexagonal;

or, the unit of the negative poisson ratio structure is a triangle, and the transverse side of the triangle is a concave arc line;

or, the units of the negative poisson ratio structure are concave hexagons which are arranged in a staggered way;

or, the units of the negative poisson ratio structure are concave hexagons which are horizontally and vertically arranged side by side.

The utility model has the following beneficial effects:

according to the interbody fusion cage, the porous structure is introduced into the design of the cage, the supporting piece positioned between the upper substrate and the lower substrate comprises the first porous area, so that the elastic modulus of the interbody fusion cage is equivalent to the elastic modulus of natural bones of a human body, the rigidity of the interbody fusion cage is reduced, the stress shielding is avoided, the problems of sinking, loosening and the like of the interbody fusion cage are prevented, the supporting piece is relatively large in volume, the porous structure is convenient to design, the existence of the porous structure is beneficial to the ingrowth of bone tissues, the osseous integration is promoted, the fusion effect is ideal, the porous structure can provide elastic deformation, the supporting piece provided with elasticity, the elastic deformation proportion range of the supporting piece is 10-40%, the interbody fusion cage can realize certain elastic deformation, the interbody fusion cage with proper elastic deformation can provide proper stress stimulation for the bone growth at the fusion position according to the wolff law, the bone fusion is promoted, the bone fusion is enhanced, the mechanical environment of the spine can also be dealt with, and the service life of the interbody fusion cage is prolonged.

Drawings

FIG. 1 is a schematic view of an embodiment 1 of an intersomatic cage of the present utility model, (a) being a perspective view and (b) being a side view of (a);

FIG. 2 is a schematic view of the interbody cage of FIG. 1 with the support member omitted;

FIG. 3 is a schematic perspective view of an intervertebral cage according to one embodiment 2 of the present utility model;

FIG. 4 is a schematic perspective view of another embodiment of the interbody cage of the present utility model in another orientation;

FIG. 5 is a schematic view of the internal structure of the interbody cage of FIG. 3;

FIG. 6 is a schematic view of the internal structure of an embodiment 3 of the interbody fusion cage of the present utility model;

FIG. 7 is a schematic view of the interbody cage of FIG. 6 with the buttress removed;

FIG. 8 is a schematic representation of a first porous region of the interbody cage of the present utility model;

FIG. 9 is a schematic representation of a second embodiment of a first porous region of the interbody cage of the present utility model;

FIG. 10 is a schematic representation of a third embodiment of a first porous region of an intersomatic cage according to the present utility model;

FIG. 11 is a schematic representation of a fourth embodiment of a first porous region of an intersomatic cage according to the present utility model;

FIG. 12 is a schematic illustration of a fifth embodiment of a first porous region of an intersomatic cage according to the present utility model;

fig. 13 is a schematic representation of the composition of a second porous region in an intersomatic cage according to the present utility model.

Detailed Description

In order to make the technical problems, technical solutions and advantages to be solved more apparent, the following detailed description will be given with reference to the accompanying drawings and specific embodiments.

The utility model provides an interbody fusion cage, as shown in fig. 1-13, comprising an upper substrate 1, a lower substrate 2 and a support 3 positioned between the upper substrate 1 and the lower substrate 2, wherein the support 3 has elasticity, and the support 3 comprises a first porous region 31, so that the elastic deformation proportion of the support is in the range of 10-40%.

When the intervertebral fusion device is used, the intervertebral fusion device is held by the holder and placed in the intervertebral space of a patient, after the intervertebral fusion device is placed in the intervertebral space, the position of the fusion device in the intervertebral space is observed through the imaging equipment, and the intervertebral fusion device is adjusted by the holder so as to be placed at a proper position.

According to the interbody fusion cage, the porous structure is introduced into the design of the cage, the supporting piece positioned between the upper substrate and the lower substrate comprises the first porous area, so that the elastic modulus of the interbody fusion cage is equivalent to the elastic modulus of natural bones of a human body, the rigidity of the interbody fusion cage is reduced, the stress shielding is avoided, the problems of sinking, loosening and the like of the interbody fusion cage are prevented, the supporting piece is relatively large in volume, the porous structure is convenient to design, the existence of the porous structure is beneficial to the ingrowth of bone tissues, the osseointegration is promoted, the fusion effect is ideal, the porous structure can provide elastic deformation, the supporting piece provided with elasticity, the elastic deformation proportion range of the supporting piece is 10-40% (for example, the height of the interbody fusion cage is 10mm, the maximum of the interbody fusion cage can be compressed to 6 mm), the interbody fusion cage with proper elastic deformation can provide proper stress stimulation for the bone growth at the fusion position according to the wolff law, the bone fusion is promoted, the bone fusion is strengthened, the bone density is also enhanced, the environment of the spine is compatible, and the service life of the interbody fusion cage is prolonged.

The utility model particularly relates to an intervertebral fusion device with adjustable elastic modulus, which is characterized in that the elastic modulus of the intervertebral fusion device is preferably kept in the range of 0.5-20Gpa because the compression strength of cortical bone of a human body is about 80-120MPa, the elastic modulus of cortical bone is about 17GPa, and the elastic modulus of trabecular bone of the human body is about 689MPa, and the intervertebral fusion device is equivalent to the elastic modulus of natural bone of the human body, so that stress shielding is avoided.

According to the design of the upper substrate 1, the lower substrate 2 and the supporting member 3, the following embodiments are possible:

example 1

As shown in fig. 1, the support 3 may be integrally formed as a first porous region 31.

Further, as shown in fig. 2, the upper substrate 1 and the lower substrate 2 may be designed in a split type, after the intervertebral fusion device in this design manner is placed in the intervertebral space of a patient, the front end and the rear end of the intervertebral fusion device may all achieve a certain elastic deformation, that is, the front end and the rear end of the intervertebral fusion device may be compressed, so as to provide more suitable stress stimulation for bone growth, better promote bone growth, and better cope with the mechanical environment of the spine.

Example 2

This embodiment is substantially the same as embodiment 1 except that:

as shown in fig. 3-5, the support 3 may further comprise a second porous region 32, the pore size of the porous structure employed by the first porous region 31 preferably being different from the pore size of the porous structure employed by the second porous region 32; the first porous region 31 and the second porous region 32 preferably have different porous structures so as to conveniently adjust the elastic modulus of the intervertebral fusion device to be equivalent to the elastic modulus of natural bones of human bodies.

Further, as shown in fig. 5, the support 3 may include an inner layer, an outer layer, and an intermediate layer between the inner layer and the outer layer, the intermediate layer being a first porous region 31, the inner layer and the outer layer being a second porous region 32 (specifically, the second porous region 32 of the outer layer and the inner layer surrounds the first porous region 31 of the intermediate layer), the first porous region 31 having a pore size larger than that of the second porous region 32.

Example 3

This embodiment is substantially the same as embodiment 2 except that:

as shown in fig. 6 to 7, the support 3 may include an inner layer and an outer layer, the inner layer is a first porous region 31, and the outer layer is a second porous region 32 (specifically, the second porous region 32 of the outer layer surrounds the first porous region 31 of the inner layer), and the pore size of the porous structure adopted by the first porous region 31 is larger than the pore size of the porous structure adopted by the second porous region 32.

Further, as shown in fig. 7, the upper substrate 1 and the lower substrate 2 may be designed as an integral unit, that is, the front ends of the upper substrate 1 and the lower substrate 2 are provided with vertical connection plates 4, after the intervertebral fusion device in such a design manner is placed in the intervertebral space of a patient, the rear end of the intervertebral fusion device may realize a certain elastic deformation, that is, the rear end of the intervertebral fusion device may be compressed, so as to provide appropriate stress stimulation for bone growth, promote bone growth, and cope with the mechanical environment of the spine.

The three embodiments can be adapted to the supporting member 3 in application, that is, in embodiments 1-2, a part of the upper and lower surfaces of the supporting member 3 can be cut to make room for the connection of the upper and lower substrates, and in embodiment 3, a part of the front end of the supporting member 3 can be cut to make room for the connection board 4.

In the above embodiment, as shown in fig. 1-2 and fig. 6-7, the rear end of the interbody fusion cage may be provided with the holder interface 5, the holder interface 5 is embedded in the rear portion of the support 3, the height of the holder interface 5 is smaller than the height between the upper substrate 1 and the lower substrate 2, and the holder interface 5 is arranged to facilitate holding of the interbody fusion cage by the holder without affecting the elastic deformation of the rear end of the interbody fusion cage. It is contemplated that the rear portion of the support member 3 may also be integrally formed with a holder interface 33, as shown in fig. 3 and 5, to facilitate holding of the interbody fusion cage by the holder.

As shown in fig. 1-4 and fig. 7, the middle parts of the upper substrate 1 and the lower substrate 2 can be provided with bone grafting windows 11 and 21, the middle part of the supporting piece 3 is provided with vertical bone grafting holes 34 communicated with the bone grafting windows 11 and 21, bone filling materials such as bone mud, bone blocks, bone powder and the like can be implanted into the bone grafting holes 34 by utilizing bone grafting machinery to penetrate through the bone grafting windows 11 and 21, so that the bone grafting fusion effect is improved, the later bone fusion is facilitated, the fixation of the intervertebral fusion device is good, the bone fusion is increased, and the clinical requirements are met.

The shape of the interbody fusion cage may be horseshoe, U-shaped, bullet-shaped, kidney-shaped, or the like. The material of the interbody fusion cage may be titanium metal, such as titanium alloy, and the like. The preparation mode of the interbody fusion cage can be a 3D printing technology so as to conveniently form a porous structure, the shape/size of the interbody fusion cage can be customized individually according to the condition and the requirement of the intervertebral space of a patient, and the interbody fusion cage with the corresponding height/angle is designed to be perfectly matched with the intervertebral space of the patient. As shown in fig. 1-4 and fig. 7, the upper substrate 1 and the lower substrate 2 may be provided with transverse anti-back teeth (barbs) 12, 22 to prevent the fusion cage from backing out and improve the stability of the fusion cage. The porosity of the porous structure employed in both the first porous region 31 and the second porous region 32 may range from 60% to 95%, preferably from 60% to 80%.

Depending on the porous structure used for the first porous region 31, it may have the following composition:

form one

As shown in fig. 8, the porous structure employed for the first porous region 31 may be a spiral structure having a stem diameter ranging from 100 to 700 μm, for example, 150 μm, 500 μm, 650 μm, etc.

Depending on the spiral structure, the following structural forms are possible:

structural form one: as shown in fig. 8 (a), the spiral structure may be an elastic single spiral structure;

and the structural form II is as follows: as shown in fig. 8 (b), the spiral structure may be an elastic double-spiral structure;

and the structural form III: as shown in fig. 8 (c), the spiral structure may be an elastic multi-spiral structure in which the number of spirals is at least three;

and the structural form is four: as shown in fig. 8 (d), the spiral structure may include at least two elastic multi-spiral structures arranged side by side, wherein the number of spirals in a single elastic multi-spiral structure is at least three.

Composition form two

As shown in fig. 9, the porous structure employed for the first porous region 31 may be a very small sheet structure having a wall thickness ranging from 100 to 700 μm, for example, 200 μm, 500 μm, 600 μm, or the like.

Depending on the monomer of the very small patch structure, the following structures may be used:

and the structural form is five: as shown in fig. 9 (a), the monomer of the micro-patch structure may be a split p structure;

structural form six: as shown in fig. 9 (b), the monomer of the very small patch structure may be a schwarz p structure;

structural form seven: as shown in fig. 9 (c), the monomer of the very small patch structure may be a neovis structure;

structural form eight: as shown in (d) of fig. 9, the monomer of the micro-patch structure may be an lidinoid structure;

structural form nine: as shown in fig. 9 (e), the monomer of the micro patch structure may be a gyroid structure.

Composition form III

As shown in fig. 10, the porous structure used for the first porous region 31 may be a woven structure having a stem diameter ranging from 100 to 700 μm, for example, 300 μm, 400 μm, 500 μm, etc.

Composition form IV

As shown in fig. 11, the porous structure used for the first porous region 31 may be an elastic folded structure having a stem diameter ranging from 100 to 700 μm, for example, 350 μm, 450 μm, 550 μm, etc.

Form five

As shown in fig. 12, the porous structure employed for the first porous region 31 may be a Thiessen polygonal structure having a wall thickness ranging from 100 to 700 μm, for example, 300 μm, 450 μm, 650 μm, etc.

As shown in fig. 13, the porous structure employed in the second porous region 32 in the present utility model may be a negative poisson's ratio structure.

Depending on the cell of the negative poisson's ratio structure, the following structural forms are possible:

and the structural form is ten: as shown in fig. 13 (a), the unit of the negative poisson's ratio structure may be a four-bladed windmill shape;

eleven structural forms: as shown in fig. 13 (b), the units of the negative poisson ratio structure may be in an i-shape with an arrangement of being embedded in each other in the horizontal and vertical directions;

twelve structural forms: as shown in fig. 13 (c), the cells of the negative poisson's ratio structure may be hexagonal;

thirteen structural forms: as shown in (d) of fig. 13, the cells of the negative poisson's ratio structure may be triangular, with the lateral sides of the triangle being concave arcs;

fourteen structural forms: as shown in (e) of fig. 13, the cells of the negative poisson's ratio structure may be concave hexagons arranged in a staggered manner;

fifteen structural forms: as shown in fig. 13 (f), the cells of the negative poisson's ratio structure may be concave hexagons side by side in a horizontal-vertical direction.

Each of the structural forms of the first porous region 31 and each of the structural forms of the second porous region 32 in the present utility model may be used alone or in combination of a plurality of structures.

While the foregoing is directed to the preferred embodiments of the present utility model, it will be appreciated by those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present utility model, and such modifications and adaptations are intended to be comprehended within the scope of the present utility model.

Claims

1. An intervertebral cage comprising an upper substrate, a lower substrate, and a support member positioned between the upper and lower substrates, the support member having elasticity, the support member comprising a first porous region such that the support member has an elastic deformation ratio in the range of 10-40%.

2. The interbody cage of claim 1, wherein the support further comprises a second porous region, wherein,

3. The interbody fusion cage of claim 2, wherein the support member includes an inner layer and an outer layer, the inner layer being the first porous region and the outer layer being the second porous region, the first porous region having a porous structure with a pore size greater than a pore size of the porous structure of the second porous region;

4. The interbody cage of claim 1, wherein the upper and lower base plates are of split design;

5. The intervertebral fusion of claim 4 wherein a holder interface is provided at a rear end of the intervertebral fusion, the holder interface being embedded in a rear portion of the support, the holder interface having a height less than a height between the upper and lower base plates;

6. The intersomatic cage according to claim 2, wherein the intersomatic cage has a horseshoe, U-shape, bullet shape or kidney shape;

and/or, the material of the interbody fusion cage is titanium metal;

7. The interbody fusion cage of claim 1, wherein the porous structure employed by the first porous region is a helical structure having a stem diameter ranging from 100-700 μιη, wherein:

the spiral structure is an elastic single-spiral structure;

or the spiral structure is an elastic double-spiral structure;

8. The interbody cage according to claim 1, wherein the porous structure employed by the first porous region is a micro-faceted structure having a wall thickness ranging from 100-700 μιη, wherein:

the monomer of the minimum patch structure is of a split p structure;

or the monomer of the extremely small patch structure is a neovis structure;

or the monomer of the minimum patch structure is an lip structure;

9. The interbody fusion cage of claim 1, wherein the porous structure employed in the first porous region is a woven or elastic folded structure having a stem diameter ranging from 100-700 μιη;

10. The interbody cage of claim 2, wherein the porous structure employed by the second porous region is a negative poisson's ratio structure, wherein:

alternatively, the cells of the negative poisson ratio structure are hexagonal;