CN113081405B

CN113081405B - Artificial vertebral body and manufacturing method thereof

Info

Publication number: CN113081405B
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: 2023-11-03
Anticipated expiration: 2041-04-08
Also published as: CN113081405A

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 part, the bearing part is sequentially provided with a solid high supporting layer and a low supporting layer densely distributed with pore structures from outside to inside, the bone cell growing part comprises an upper fusion layer, a lower fusion layer, an outer layer and a bone grafting pore 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 pore layer is cylindrical and penetrates through the upper fusion layer, the low supporting layer and the lower fusion layer, and a plurality of pore groove structures for bone cell growing are distributed on the surface of the bone cell growing part. The bearing portion can be designed according to the original centrum structure of human body, the loaded condition, avoids the conditions such as insufficient supporting strength and stress shielding, and the hole groove structure that bone cell growth portion surface was seted up can be designed according to the condition that is fit for bone cell growth more, avoids receiving the influence of other factors, makes the original bone structure of human body better with the fusion nature of artifical centrum.

Description

Artificial vertebral body and manufacturing method thereof

Technical Field

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

Background

The spine is a complex exercise function chain, is a central shaft pillar of a human body, and plays roles in supporting the trunk and protecting the spinal cord and other organs. Vertebral lesions due to tuberculosis, tumors, trauma, deformities, etc. often require removal of the patient's diseased vertebral body, and the integrity and biomechanical properties of the spine are compromised, thus requiring implantation of artificial vertebral body substitutes to reconstruct the sequence integrity and biomechanical properties of the spine.

At present, the structure type of the artificial vertebral body is a topological optimization structure which is made by simulating the structure form of the bone of the human body and is used for realizing better mechanical properties. The invention patent application of application number 202010471134.7 discloses a vertebral body prosthesis, which comprises a wing plate, an upper vertebral body end, a middle vertebral body and a lower vertebral body end, wherein the upper vertebral body end and the lower vertebral body end are directly contacted with a bone surface, the middle vertebral body comprises a trabecular bone structure and a solid structure, the solid structure is arranged on the outer side of a trabecular bone and imitates the original cortical bone of a human body, and the trabecular bone structure is provided with a plurality of holes for inducing bone ingrowth. However, in the patent, bone cells can be induced to grow into bone grafting holes on the upper surface, the lower surface and the inner part, but the outer layer in the middle of the vertebral body is of a solid structure, so that the bone cells cannot grow into the bone grafting holes, and the fusion property of the bone grafting holes with the bone cells of the human body is poor; meanwhile, the trabecular bone structure plays a supporting role and a role of enabling bone cells to grow in, the two roles have different requirements on the size and the distribution form of holes, and the requirements of the two roles can not be met well. The invention patent application with the application number of 201911022199.7 discloses a topological optimization artificial vertebral body and a design method thereof, wherein the artificial vertebral body comprises a topological thin-wall structure with holes and a porous structure arranged in the hole topological thin-wall structure, the topological thin-wall structure is designed in a lightweight 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 lightweight design and the strength of a supporting structure, namely the supporting strength of the topological thin-wall structure, the condition matched with the supporting strength of a human body self-spinal structure, the stress distribution condition and the like are required to be preferentially considered by the structure, the position and the size of the holes are selected on the basis, and the hole setting based on the structure can not be well suitable for the bone ingrowth condition of bone cells, so that the fusion property of the artificial vertebral body and the human body self-bone is poor.

Disclosure of Invention

The invention aims to provide an artificial vertebral body and a manufacturing method thereof, which solve the problems in the prior art, and by arranging a bearing part and a bone cell growing part, the bearing part can be designed according to the original vertebral body structure of a human body and the loaded condition, so that the conditions of insufficient supporting strength, stress shielding and the like are avoided, the bone cell growing part is attached to the surface of the bearing part, the hole groove structure formed on the surface can be designed according to the condition more suitable for bone cell growing, the influence of other factors is avoided, and the fusion property of the original bone structure of the human body and the artificial vertebral body is better.

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

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

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

Preferably, the low support layer comprises a plurality of tube structures in a honeycomb array, the axes of the tube structures being arranged along the axial direction of the low support layer.

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

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

Preferably, thorn-shaped protrusions are arranged on the outer surfaces of the upper fusion layer and the lower fusion layer.

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

1) Acquiring spine data of a human body to be implanted part, constructing an original spine model according to the spine data, and cutting vertebral bodies at lesion parts on the original spine model to obtain two sections of normal vertebral body models adjacent to the artificial vertebral body;

2) Acquiring contour data of adjacent surfaces of the normal cone model and the artificial cone and primary physiological curvature data of the excision part, and establishing an artificial cone appearance model with a hole and slot structure on the surface according to the acquired data;

3) Analyzing the stress conditions of the spine when a human body stands, sits, bends forwards and backwards, bends leftwards and rightwards and twists to obtain the load of the pathological part in the maximum stress state of the vertebral body, performing topological optimization design on the external model of the artificial vertebral body according to the obtained load, setting a low stress area as a low support layer, setting a high stress area as a high support layer, and obtaining a specific structural model of the artificial vertebral body;

4) Verifying the mechanical property of the specific structural model of the artificial vertebral body, if the mechanical property meets the requirement, carrying out the next step, and if the mechanical property does not meet the requirement, repeating the step 3) until the mechanical property meets the requirement, so as to obtain a final artificial vertebral body model;

5) And 3D printing is carried out according to the final artificial vertebral body model, so that an artificial vertebral body entity is obtained.

Preferably, the 3D printing in step 5) employs a dual-jet printer, wherein one jet prints the load-bearing portion with CFR-PEEK material and the other jet prints the bone cell ingrowth portion with PEEK/GO/HA composite material.

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

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

1. through setting up bearing portion and bone cell growth income portion, make the bearing portion design according to the former centrum structure of human body, the loaded condition, avoid appearing the condition such as support strength is insufficient and stress shelter from, and bone cell growth income portion is laminated with bearing portion surface, and the hole groove structure of surface seting up can design according to the condition that is fit for bone cell growth income more, avoids receiving the influence of other factors, makes the fusion of the former bone structure of human body and artifical centrum better.

2. The bearing part adopts CFR-PEEK (carbon fiber reinforced polyether ether ketone), and on the premise of retaining the excellent characteristic of PEEK, the high-strength characteristic of carbon fiber is utilized, so that the bearing part has better strength and stronger energy for bearing load; meanwhile, the biological inertia and the surface hydrophilicity of the pure PEEK are poor, and the adhesion growth of osteoblasts is not facilitated, so that the PEEK/GO/HA composite material is adopted at the bone cell growth part, the biocompatibility of PEEK can be improved by GO (graphene oxide) and HA (hydroxyapatite), the combination of the surface of an artificial vertebral body and surrounding bone tissues can be promoted, 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 of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

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

wherein, 1, a high support layer; 2. a low support layer; 3. an upper fusion layer; 4. a lower fusion layer; 5. an outer layer; 6. bone grafting pore layer; 7. a hole groove structure; 8. a concave portion; 9. a tube structure; 10. thorn-like bulges.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The invention aims to provide an artificial vertebral body and a manufacturing method thereof, which are used for solving the problems in the prior art, and by arranging a bearing part and a bone cell growing part, the bearing part can be designed according to the original vertebral body structure of a human body and the loaded condition, so that the conditions of insufficient supporting strength, stress shielding and the like are avoided, the bone cell growing part is attached to the surface of the bearing part, the hole groove structure formed on the surface can be designed according to the condition more suitable for bone cell growing, the influence of other factors is avoided, and the fusion property of the original bone structure of the human body and the artificial vertebral body is better.

In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.

Please refer to fig. 1

Example 1

The embodiment provides an artificial vertebral body, which comprises a bearing part and a bone cell growing 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 covered with a hole structure and bears relatively lower stress, the hole structure can be a hole structure with consistent size or a hole structure with inconsistent size, the high supporting layer 1 and the low supporting layer 2 are combined to jointly play a bearing role, the strength requirement can be met, the mechanical properties of the artificial vertebral body and tissues around an implantation part are matched, the stress shielding is reduced, and the problems of osteoporosis and the like caused by the 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, wherein 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 to form a closed ring-like cavity, the bearing part is arranged in the ring-like cavity, namely, the bearing part is wrapped inside by 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, during operation, the bone cell growing part can be implanted into the bone of a patient in the front outer surface of an artificial vertebral body and the bone grafting hole layer 6 so as to improve the fusion quality, and the bone forming structure 7 is beneficial to the peripheral vascular growing and nutrient metabolism, so as to promote the bone integration of the bone of the patient and the bone cell growing part; meanwhile, as a small amount of autologous bone of a patient needs to be implanted on the front outer surface of the artificial vertebral body, but the bone is not implanted at the rear of the artificial vertebral body (the rear part is the side with the concave part 8 in fig. 1), the hole groove structure 7 can be arranged on the outer layer 5 at the rear 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, and is preferably a blind hole, and by arranging the hole groove structure 7 as a blind hole, bone cells can be well contacted with the hole wall of the hole groove structure 7 and the bottom of the blind hole when bone cells grow, so that the fusion property of the bone cells and the bone cell growing part is better, the depth of the blind hole is preferably 1mm, and of course, the depth of the blind hole can also be 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 growth income portion, make the bearing portion design according to the former centrum structure of human body, the loaded condition, avoid appearing the condition such as support strength is insufficient and stress shelter from, and bone cell growth income portion is laminated with bearing portion surface, the hole groove structure 7 of surface seting up can design according to the condition that is fit for bone cell growth income more, avoid receiving the influence of other factors, make the integration of the former bone structure of human body and artifical centrum better.

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

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

Further, the low support 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 support layer 2, and the low support 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 support layer 2, and meanwhile, the mechanical property matching with surrounding tissues is realized.

Further, the diameter of the pipe structure 9 is gradually increased from outside to inside, namely, a state of osteoporosis is formed from outside to inside, 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.

Further, the size of the cell structure 7 is 400 to 600 μm, and in this size range, it is more suitable for bone cell ingrowth.

In a preferred embodiment, the outer surfaces of the upper fusion layer 3 and the lower fusion layer 4 are provided with thorn-shaped bulges 10, and when the artificial vertebral body is implanted, the thorn-shaped bulges 10 penetrate into the surface of a natural vertebral endplate connected with the artificial vertebral body, so as to fix the artificial vertebral body, prevent the artificial vertebral body from being misplaced relative to the natural vertebral body, and the like.

In one embodiment, a recess 8 is provided behind the artificial vertebral body, the recess 8 being designed according to the recess of the natural vertebral body at that location, but the size of the recess 8 is larger than the recess of the natural vertebral body at that location, by setting the recess 8 to a larger size, the pressure on the spinal cord at that location is reduced, facilitating restoration of spinal cord function.

Example two

On the basis of the artificial vertebral body structure provided in the first embodiment, the present embodiment provides a method for manufacturing an artificial vertebral body, including the following steps,

1) Acquiring spine data of a human body to be implanted part, constructing an original spine model according to the spine data, and cutting off vertebral bodies at lesion parts on the original spine model to obtain two sections of normal vertebral body models adjacent to the artificial vertebral body;

the method comprises the STEPs of obtaining spine data, utilizing CT to scan spine tissues around an artificial vertebral body part to be implanted into a patient, scanning the thickness of a layer to be 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 in the range of a pathological change vertebral body and adjacent vertebral bodies, extracting skeleton data, constructing a three-dimensional model of the pathological change vertebral body and adjacent vertebral bodies, namely an original spine model, exporting an STL format model, importing the STL format model into reverse engineering software, diagnosing triangular patches, repairing holes, smoothing and the like, repairing the STL format model, resecting the pathological change part vertebral bodies according to an operation scheme, and storing the resected model in a STEP format to obtain two sections of normal vertebral body models which are adjacent to the artificial vertebral bodies;

the foregoing describes a specific embodiment, and the data acquisition mode, the obtained model format type, etc. may be changed to other forms according to practical situations, which are not limitations of the present invention.

2) Acquiring contour data of the adjacent surfaces of a normal cone model and an artificial cone and primary physiological curvature data of a cutting part, and establishing an artificial cone appearance model with a hole-slot structure 7 on the surface according to the acquired data, wherein the model can be established by adopting commonly used three-dimensional software in the step;

3) Analyzing the stress conditions of the spine when a human body stands, sits, bends forwards and backwards, bends left and right and twists sideways, adopting AnyBody software to perform the analysis to obtain the load of the vertebral body at the pathological part in the maximum stress state, and introducing the load of the vertebral body at the pathological part in the maximum stress state and the artificial vertebral body model obtained in the step 2) into Altair Inpire software to perform topological optimization design on the artificial vertebral body model, setting a low stress area as a low support layer 2 and setting a high stress area as a high support layer 1 to obtain the specific structural model of the artificial vertebral body;

4) Verifying the mechanical property of the specific structural model of the artificial vertebral body, if the mechanical property meets the requirement, carrying out the next step, and if the mechanical property does not meet the requirement, repeating the step 3) to carry out the topology optimization design again until the mechanical property meets the requirement, so as to obtain the final artificial vertebral body model; when the step 3) is repeated, the analysis of the stress condition can be carried out without repeated operation, and only the topology optimization design is carried out on the model of the outer shape of the artificial vertebral body again;

In the above steps, the analysis software, modeling software, etc. may be replaced by software having similar functions, which is used to describe the whole manufacturing process more clearly, and is not a limitation of the present invention.

In one embodiment, the 3D printing in step 5) employs a dual jet printer, wherein one jet prints the load bearing portion using CFR-PEEK material and the other jet prints the bone cell ingrowth portion using a PEEK/GO/HA composite material.

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

The adaptation to the actual need is within the scope of the invention.

The principles and embodiments of the present invention have been described in detail with reference to specific examples, which are provided to facilitate understanding of the method and core ideas of the present invention; also, it is within the scope of the present invention to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the invention.

Claims

1. An artificial vertebral body, characterized in that: the bone grafting cell growth device comprises a bearing part and a bone cell growth part, wherein a solid high supporting layer and a low supporting layer densely distributed with a pore structure are sequentially arranged on the bearing part from outside to inside, the bone cell growth part comprises an upper fusion layer, a lower fusion layer, an outer layer and a bone grafting pore 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, thorn-shaped bulges are respectively arranged on the outer surfaces of the upper fusion layer and the lower fusion layer, the bone grafting pore layer is cylindrical and penetrates through the upper fusion layer, the low supporting layer and the lower fusion layer, a plurality of pore structures for bone cell growth are distributed on the surface of the bone cell growth part, the low supporting layer comprises a plurality of honeycomb-shaped array pipe structures, the axes of the pipe structures are axially arranged along the low supporting layer, and the diameters of the pipe structures are sequentially increased from outside to inside;

the bearing part is made of high-strength materials, and the bone cell growing part is made of materials with high biocompatibility.

2. An artificial vertebral body according to claim 1, wherein: the bearing part is made of CFR-PEEK material, and the bone cell ingrowth part is made of PEEK/GO/HA composite material.

3. An artificial vertebral body according to claim 1, wherein: the size of the pore groove structure is 400-600 micrometers.

4. A method of making an artificial vertebral body according to claim 1, wherein: comprises the steps of,

5. The manufacturing method according to claim 4, wherein: 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 ingrowth part.

6. The manufacturing method according to claim 5, characterized in that: and 6) carrying out mechanical verification on the artificial vertebral body entity, if the mechanical property is met, completing the preparation, and if the mechanical property is not met, repeating the steps 3) to 5).