CN113081405A

CN113081405A - Artificial vertebral body and manufacturing method thereof

Info

Publication number: CN113081405A
Application number: CN202110376105.7A
Authority: CN
Inventors: 乌日开西·艾依提; 蒋厚峰
Original assignee: Xinjiang University
Current assignee: Xinjiang University
Priority date: 2021-04-08
Filing date: 2021-04-08
Publication date: 2021-07-09
Anticipated expiration: 2041-04-08
Also published as: CN113081405B

Abstract

The invention discloses an artificial vertebral body and a manufacturing method thereof, wherein the artificial vertebral body comprises a bearing part and a bone cell growing-in part, the bearing part is sequentially provided with a solid high supporting layer and a solid low supporting layer densely distributed with porous structures from outside to inside, the bone cell growing-in part comprises an upper fusion layer, a lower fusion layer, an outer layer and a bone grafting hole layer, the upper fusion layer, the lower fusion layer and the outer layer are respectively attached to the upper surface, the lower surface and the outer side wall of the bearing part, the bone grafting hole layer is cylindrical and penetrates through the upper fusion layer, the lower supporting layer and the lower fusion layer, and a plurality of hole groove structures for bone cells to grow in are distributed on the surface of the bone cell growing-in part. The bearing part can be designed according to the original human vertebral body structure and the load condition received, the situations that the supporting strength is insufficient and the stress is shielded are avoided, the hole groove structure formed on the surface of the bone cell growing part can be designed according to the situation that the bone cells grow into the hole groove structure, the influence of other factors is avoided, and the integration of the original human bone structure and the artificial vertebral body is better.

Description

Artificial vertebral body and manufacturing method thereof

Technical Field

The invention relates to the technical field of medical instruments, in particular to an artificial vertebral body and a manufacturing method thereof.

Background

The spine is a complex functional kinematic chain, is a central shaft support of a human body and plays roles in supporting the trunk and protecting the spinal cord and other organs. Lesions of the vertebral body due to tuberculosis, tumors, trauma, deformity, etc. often require removal of the diseased vertebral body of the patient, and the integrity and biomechanical properties of the spine are compromised, thus requiring implantation of an artificial vertebral body substitute to reconstruct the sequence integrity and original biomechanical properties of the spine.

At present, the structural type of the artificial vertebral body is a topological optimization structure which is performed by simulating the structural form of the bone of the human body and realizing better mechanical property. For example, the patent application with the application number of 202010471134.7 discloses a vertebral body prosthesis, which comprises a wing plate, an upper end of a vertebral body, a middle part of the vertebral body and a lower end of the vertebral body, wherein the upper end of the vertebral body and the lower end of the vertebral body are directly contacted with a bone surface, the middle part of the vertebral body comprises a bone trabecula structure and a solid structure, the solid structure is arranged on the outer side of the bone trabecula and simulates the original cortical bone of a human body, and the bone trabecula structure is provided with a plurality of. However, in the patent, only the bone grafting holes on the upper surface, the lower surface and the inside can induce bone cells to grow in, but the outer layer in the middle of the vertebral body is of a solid structure, so that the bone cells cannot grow in, and the fusion of the bone cells and the bone cells of the human body is poor; meanwhile, the trabecular bone structure has the functions of supporting and growing bone cells, and the two functions have different requirements on the size and the distribution form of holes, so that the requirements of the two functions cannot be met well. The invention patent application with the application number of 201911022199.7 discloses a topological optimized artificial vertebral body and a design method thereof, the artificial vertebral body comprises a topological thin-wall structure with an opening and a porous structure arranged in the topological thin-wall structure with the opening, wherein the topological thin-wall structure is designed in a light weight manner, the porous structure is added to meet the bone ingrowth requirement on the basis of meeting the strength requirement of a prosthesis in different motion states, but the porous structure is added to enable bone cells to grow in on the basis of meeting the light weight design and the strength of a supporting structure, namely the supporting strength of the topological thin-wall structure and the supporting strength matched with the spinal column structure of a human body, the stress distribution condition and the like are preferentially considered in the structure, the position and the size of the opening are selected on the basis, and the opening arrangement based on the method can not well adapt to the ingrowth condition of the bone cells, therefore, the artificial vertebral body has poor fusion with the bone of the human body.

Disclosure of Invention

The invention aims to provide an artificial vertebral body and a manufacturing method thereof, aiming at solving the problems in the prior art, the bearing part and the bone cell growing-in part are arranged, so that the bearing part can be designed according to the structure and the load condition of the human original vertebral body, the situations of insufficient supporting strength, stress shielding and the like are avoided, the bone cell growing-in part is attached to the surface of the bearing part, the hole groove structure arranged on the surface can be designed according to the condition more suitable for the growth of bone cells, the influence of other factors is avoided, and the fusion of the human original bone structure and the artificial vertebral body is better.

In order to achieve the purpose, the invention provides the following scheme: the invention provides an artificial vertebral body which comprises a bearing part and a bone cell growing-in part, wherein the bearing part is sequentially provided with a solid high supporting layer and a low supporting layer densely distributed with porous structures from outside to inside, the bone cell growing-in part comprises an upper fusion layer, a lower fusion layer, an outer layer and a bone grafting hole layer, the upper fusion layer, the lower fusion layer and the outer layer are respectively attached to the upper surface, the lower surface and the outer side wall of the bearing part, the bone grafting hole layer is cylindrical and penetrates through the upper fusion layer, the lower supporting layer and the lower fusion layer, and a plurality of hole groove structures for bone cells to grow in are distributed on the surface of the bone cell growing-in part.

Preferably, the weight bearing part is made of a high-strength material, and the bone cell growing part is made of a material with high biocompatibility.

Preferably, the load bearing part is made of CFR-PEEK material, and the bone cell growing part is made of PEEK/GO/HA composite material.

Preferably, the low supporting layer comprises a plurality of tube structures in a honeycomb array, and axes of the tube structures are arranged along an axial direction of the low supporting layer.

Preferably, the diameter of the tube structure increases from the outside to the inside in diameter.

Preferably, the size of the pore-groove structure is 400-600 microns.

Preferably, the outer surfaces of the upper fusion layer and the lower fusion layer are both provided with thorn-shaped protrusions.

It is still another object of the present invention to provide a method for manufacturing an artificial vertebral body, comprising the steps of,

1) obtaining spine data of a planned implantation part of a human body, building an original spine model according to the spine data, and cutting off a pathological change part vertebral body on the original spine model to obtain two sections of normal vertebral body models adjacent to an artificial vertebral body;

2) acquiring contour data of the adjacent surface of the normal vertebral body model and the artificial vertebral body and primary physiological curvature data of a cut part, and establishing an artificial vertebral body appearance model with a pore-groove structure on the surface according to the acquired data;

3) analyzing the stress condition of the spine when a human body stands, sits, bends forwards and backwards, bends left and right, and twists to obtain the load of the pathological change part in the maximum stress state of the centrum, performing topology optimization design on the artificial centrum appearance model according to the obtained load, setting a low stress area as a low supporting layer, and setting a high stress area as a high supporting layer to obtain a specific structure model of the artificial centrum;

4) verifying the mechanical property of the specific structure model of the artificial vertebral body, if the specific structure model meets the requirements, carrying out the next step, and if the specific structure model does not meet the requirements, repeating the step 3) until the requirements are met to obtain a final artificial vertebral body model;

5) and 3D printing is carried out according to the final artificial vertebral body model to obtain an artificial vertebral body entity.

Preferably, the 3D printing in the step 5) adopts a double-nozzle printer, wherein one nozzle adopts CFR-PEEK material to print the bearing part, and the other nozzle adopts PEEK/GO/HA composite material to print the bone cell growing-in part.

Preferably, the method further comprises the step 6) of carrying out mechanical verification on the artificial vertebral body entity, finishing preparation if the mechanical property is met, and repeating the steps 3) to 5) if the mechanical property is not met.

Compared with the prior art, the invention has the following technical effects:

1. through setting up bearing portion and bone cell portion of growing into, make bearing portion can design according to human former centrum structure, the load condition that receives, avoid appearing supporting strength inadequately and the stress condition such as shelter from, and bone cell portion of growing into and bearing portion surface laminating, the hole groove structure that the surface was seted up can design according to the condition that is fit for bone cell more and grows into, avoids receiving the influence of other factors, makes the integration nature of human former bone texture structure and artificial centrum better.

2. The load-bearing part adopts CFR-PEEK (carbon fiber reinforced polyether ether ketone), and utilizes the high-strength characteristic of the carbon fiber on the premise of keeping the excellent characteristic of the PEEK, so that the load-bearing part has better strength and stronger energy for bearing load; meanwhile, pure PEEK is poor in biological inertia and surface hydrophilicity and is not beneficial to the attachment and growth of osteoblasts, so that a PEEK/GO/HA composite material is adopted in a bone cell growing part, GO (graphene oxide) and HA (hydroxyapatite) can improve the biocompatibility of the PEEK and can promote the combination of the surface of the artificial vertebral body and surrounding bone tissues, and the load bearing capacity and the combination capacity with the surrounding bone tissues of the artificial vertebral body are improved by adopting the two materials.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a schematic view of an artificial vertebral body structure;

wherein, 1, a high supporting layer; 2. a low support layer; 3. an upper fusion layer; 4. a lower fusion layer; 5. an outer layer; 6. grafting a bone hole layer; 7. a hole and groove structure; 8. a recess; 9. a tube structure; 10. a thorn-shaped bulge.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention aims to provide an artificial vertebral body and a manufacturing method thereof, aiming at solving the problems in the prior art, the bearing part and the bone cell growing-in part are arranged, so that the bearing part can be designed according to the structure and the load condition of the human original vertebral body, the situations of insufficient supporting strength, stress shielding and the like are avoided, the bone cell growing-in part is attached to the surface of the bearing part, the hole groove structure arranged on the surface can be designed according to the situation more suitable for the growth of bone cells, the influence of other factors is avoided, and the fusion of the human original bone structure and the artificial vertebral body is better.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

Please refer to fig. 1

Example one

The embodiment provides an artificial vertebral body, which comprises a bearing part and a bone cell growing-in part, wherein the bearing part is sequentially provided with a high supporting layer 1 and a low supporting layer 2 from outside to inside, the high supporting layer 1 is a solid layer and can bear higher stress, the low supporting layer 2 is densely distributed with porous structures and can bear relatively lower stress, the porous structures can be porous structures with the same size or porous structures with different sizes, the high supporting layer 1 and the low supporting layer 2 are combined to play a bearing role together, the strength requirement can be met, meanwhile, the mechanical properties of the artificial vertebral body and tissues around an implanted part are matched, stress shielding is reduced, and the problems of osteoporosis and the like caused by stress shielding are avoided; the bone cell growing part comprises an upper fusion layer 3, a lower fusion layer 4, an outer layer 5 and a bone grafting hole layer 6, the upper fusion layer 3, the lower fusion layer 4 and the outer layer 5 are respectively attached to the upper surface, the lower surface and the outer side wall of the bearing part, the bone grafting hole layer 6 is cylindrical and penetrates through the upper fusion layer 3, the lower support layer 2 and the lower fusion layer 4, the upper fusion layer 3, the outer layer 5, the lower fusion layer 4 and the bone grafting hole layer 6 are enclosed into a closed ring-like cavity, a bearing part is arranged in the ring-like cavity, namely the bearing part is wrapped in the bone cell growing part, a plurality of hole groove structures 7 for bone cell growing are distributed on the surface of the bone cell growing part, the self bone of a patient can be implanted into the outer surface in front of the artificial vertebral body and the bone grafting hole layer 6 to improve the fusion quality during an operation, the hole groove structures 7 arranged on the bone cell growing part are beneficial to the growth of peripheral blood, promoting osteogenesis and facilitating osseointegration of autologous bones of the patient and bone cell growing parts; meanwhile, as a small amount of autologous bone of the patient needs to be implanted into the outer surface in front of the artificial vertebral body and is not implanted into the back of the artificial vertebral body (the back is the side with the concave part 8 in figure 1), the hole-groove structure 7 can be arranged on the outer layer 5 in back of the artificial vertebral body or not; the sizes of the hole-groove structures 7 among the upper fusion layer 3, the lower fusion layer 4, the outer layer 5 and the bone grafting hole layer 6 can be consistent or inconsistent, and the hole-groove structures 7 respectively arranged on each layer can be consistent or inconsistent; the hole-groove structure 7 can be a through hole or a blind hole, preferably, the hole-groove structure 7 is a blind hole, when bone cells grow, the bone cells can be well contacted with the hole wall of the hole-groove structure 7 and the bottom of the blind hole, so that the integration of the bone cells and the bone cell growing part is better, the depth of the blind hole is preferably 1mm, and certainly, other sizes smaller than 1mm or larger than 1mm, such as other sizes in the range of 0.5 mm-2 mm, and the like; through setting up bearing portion and bone cell portion of growing into, make bearing portion can design according to human former centrum structure, the load condition that receives, avoid appearing supporting strength inadequately and the stress condition such as shelter from, and bone cell portion of growing into and bearing portion surface laminating, the hole groove structure 7 that the surface was seted up can design according to the condition that is fit for bone cell more and grows into, avoids receiving the influence of other factors, makes the integration nature of human former bone structure and artificial centrum better.

In order to further improve the structural strength of the bearing part and the fusion effect of the bone cell growing part and the bone cells, in one embodiment, different materials are used for the bearing part and the bone cell growing part, wherein the bearing part is made of a high-strength material, such as a metal material such as titanium alloy, or a polymer material, a composite material, and the bone cell growing part is made of a material with strong biocompatibility, such as a polymer material, a composite material, and the like.

In a preferred embodiment, the load-bearing part is made of CFR-PEEK (carbon fiber reinforced polyetheretherketone) material, and the bone cell growing-in part is made of PEEK/GO/HA (polyetheretherketone/graphene oxide/hydroxyapatite) composite material; the PEEK (polyether-ether-ketone) has excellent mechanical property, both toughness and rigidity, stable chemical property, fatigue resistance, no toxicity, good X-ray light transmittance and elastic modulus close to that of normal human bone tissues; on the premise of keeping the excellent characteristics, the carbon fiber reinforced polyether-ether-ketone makes use of the high strength characteristic of the carbon fiber to ensure that the bearing part has better strength and stronger energy for bearing load; meanwhile, pure PEEK is poor in biological inertia and surface hydrophilicity and is not beneficial to the attachment and growth of osteoblasts, GO (graphene oxide) and HA (hydroxyapatite) can improve the biocompatibility of the PEEK and can promote the combination of the surface of the artificial vertebral body and surrounding bone tissues, and the load bearing capacity and the combination capacity with the surrounding bone tissues of the artificial vertebral body are improved by adopting the two materials.

Furthermore, the low supporting layer 2 comprises a plurality of tube structures 9 in a honeycomb array, the axes of the tube structures 9 are arranged along the axial direction of the low supporting layer 2, and the low supporting layer 2 has the characteristics of low weight, high rigidity, high strength-to-weight ratio and the like by arranging the tube structures 9 in the honeycomb array and enabling the axes of the tube structures 9 to be consistent with the axial direction of the low supporting layer 2, and meanwhile, the mechanical property matching with surrounding tissues is realized.

Furthermore, the diameter of the tube structure 9 increases progressively from outside to inside, that is, the diameter from outside to inside forms a state of increasingly loose bone, and the structure of the natural vertebral body of the human body is simulated, so that the mechanical property matching degree of the artificial vertebral body and the natural vertebral body is higher.

Furthermore, the size of the hole-groove structure 7 is 400-600 microns, and under the size range, the bone cells are more suitable to grow in.

In a preferred embodiment, the outer surfaces of the upper fusion layer 3 and the lower fusion layer 4 are both provided with spinous projections 10, and when the artificial vertebral body is implanted, the spinous projections 10 penetrate into the surface of the endplate of the natural vertebral body connected with the artificial vertebral body, so that the artificial vertebral body is fixed, and the artificial vertebral body is prevented from being dislocated relative to the natural vertebral body.

In one embodiment, the artificial vertebral body is provided with a recess 8 at the back, the recess 8 is designed according to the recess of the natural vertebral body at the position, but the size of the recess 8 is larger than that of the recess of the natural vertebral body at the position, and the pressure on the spinal cord at the position is reduced by setting the recess 8 to be larger, so that the function recovery of the spinal cord is promoted.

Example two

On the basis of the artificial vertebral body structure provided by the first embodiment, the embodiment provides a manufacturing method of the artificial vertebral body, which comprises the following steps,

acquiring spine data, wherein the spine data can be implanted into spine tissues around an artificial vertebral body part of a patient by utilizing CT scanning, the scanning layer thickness is less than 1mm, outputting the scanned data in a DICOM format, importing a DICOM format file into medical image processing software, importing CT scanning layered images of a diseased vertebral body and the range of the diseased vertebral body adjacent to the diseased vertebral body, extracting bone data, constructing a three-dimensional model of the diseased vertebral body and the adjacent vertebral body, namely an original vertebral column model, exporting an STL format model, importing the STL format model into reverse engineering software, diagnosing a triangular patch, performing hole repairing, fairing and other operations, repairing the STL format model, then removing the diseased part vertebral body according to an operation scheme, storing the removed model into an STEP format, and obtaining two sections of normal vertebral body models adjacent to the artificial vertebral body;

the above is a specific embodiment, and the data acquisition mode and the model format type of the acquisition may be changed into other modes according to the actual situation, which is not a limitation of the present invention.

2) Acquiring contour data of the adjacent surfaces of the normal vertebral body model and the artificial vertebral body and primary physiological curvature data of the cut part, and establishing an artificial vertebral body appearance model with a pore-groove structure 7 on the surface according to the acquired data, wherein the established model can be established by adopting common three-dimensional software;

3) analyzing the stress condition of the spine when a human body stands, sits, bends forwards and backwards, bends left and right, and twists, wherein AnyBody software can be adopted to carry out the analysis to obtain the load of the pathological change part in the maximum stress state of the vertebral body, and the load of the pathological change part in the maximum stress state of the vertebral body and the artificial vertebral body shape model obtained in the step 2) are led into Altair Inspire software to carry out topology optimization design on the artificial vertebral body shape model, wherein a low stress area is set as a low support layer 2, and a high stress area is set as a high support layer 1 to obtain a specific structure model of the artificial vertebral body;

4) verifying the mechanical property of the specific structure model of the artificial vertebral body, if the specific structure model meets the requirements, carrying out the next step, and if the specific structure model does not meet the requirements, repeating the step 3) to carry out topology optimization design again until the requirements are met, thereby obtaining the final artificial vertebral body model; when the step 3) is repeated, repeated operation can not be carried out on the analysis of the stress condition, and only the topological optimization design is carried out on the artificial vertebral body appearance model again;

In the above steps, the related analysis software, modeling software, etc. may be replaced by software with similar functions, which is not intended to limit the present invention for more clear description of the whole manufacturing process.

In one embodiment, the 3D printing in the step 5) adopts a dual-nozzle printer, wherein one nozzle adopts CFR-PEEK material to print the bearing part, and the other nozzle adopts PEEK/GO/HA composite material to print the bone cell growing-in part.

Further, the method also comprises the step 6) of carrying out mechanical verification on the artificial vertebral body entity, finishing the preparation if the mechanical property is met, and repeating the steps 3) to 5) if the mechanical property is not met.

The adaptation according to the actual needs is within the scope of the invention.

The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims

1. An artificial vertebral body, comprising: the bone cell growth part comprises an upper fusion layer, a lower fusion layer, an outer layer and a bone grafting pore layer, wherein the upper fusion layer, the lower fusion layer and the outer layer are respectively attached to the upper surface, the lower surface and the outer side wall of the bearing part, the bone grafting pore layer is cylindrical and penetrates through the upper fusion layer, the lower support layer and the lower fusion layer, and a plurality of pore groove structures for bone cells to grow into are distributed on the surface of the bone cell growth part.

2. An artificial vertebral body according to claim 1 wherein: the bearing part is made of high-strength materials, and the bone cell growing part is made of materials with strong biocompatibility.

3. An artificial vertebral body according to claim 2 wherein: the load-bearing part is made of CFR-PEEK materials, and the bone cell growing-in part is made of PEEK/GO/HA composite materials.

4. An artificial vertebral body according to any one of claims 1-3 wherein: the low supporting layer comprises a plurality of tube structures in a honeycomb array, and the axes of the tube structures are arranged along the axial direction of the low supporting layer.

5. An artificial vertebral body according to claim 4 wherein: the diameters of the pipe structures are increased from outside to inside in sequence.

6. An artificial vertebral body according to claim 1 wherein: the size of the hole-groove structure is 400-600 microns.

7. An artificial vertebral body according to claim 1 wherein: the outer surfaces of the upper fusion layer and the lower fusion layer are both provided with thorn-shaped bulges.

8. A method of manufacturing an artificial vertebral body, comprising: comprises the following steps of (a) carrying out,

9. The method of claim 8, wherein the step of applying the artificial vertebral body comprises: and 3D printing in the step 5) adopts a double-nozzle printer, wherein one nozzle adopts CFR-PEEK material to print the bearing part, and the other nozzle adopts PEEK/GO/HA composite material to print the bone cell growing part.

10. The method of claim 9, wherein the step of applying the artificial vertebral body comprises: and 6) carrying out mechanical verification on the artificial vertebral body entity, finishing preparation if the mechanical property is met, and repeating the steps 3) to 5) if the mechanical property is not met.