CN112274299A

CN112274299A - Porous metal and PEEK composite implanted joint prosthesis and preparation method thereof

Info

Publication number: CN112274299A
Application number: CN202011309452.XA
Authority: CN
Inventors: 刘飞; 谢海琼; 张凯飞
Original assignee: Chongqing Xike Medical Technology Co Ltd
Current assignee: Chongqing Xike Medical Technology Co Ltd
Priority date: 2020-11-20
Filing date: 2020-11-20
Publication date: 2021-01-29

Abstract

The invention discloses an implanted joint prosthesis composed of porous metal and PEEK and a preparation method, including a bone fusion end, an injection molding sealing plate and a macroporous end, a plurality of fixing posts on the bone fusion end connected with a micropore layer, a support plate and a microporous layer. The microporous layers are connected, the macroporous layer at the macroporous end is arranged on one side of the microporous layer, and the PEEK layer covers the macroporous layer. The initial fixation is provided by a plurality of fixation posts and holes drilled in the host bone. A microporous layer is provided at one end of the fixation posts, so that the elastic modulus of the metal implant can be reduced, and stress shielding can be avoided. In addition, the connected micropores Provide space for the ingrowth of bone tissue; the macroporous layer is made of titanium alloy, cobalt-chromium-molybdenum alloy, and tantalum alloy, and there are multiple holes on it, which is convenient for the melted PEEK material to enter the connected pores during injection molding, forming the mutual embedding of the two materials It can effectively improve the osteoconductivity and osteogenic ability of the implant and prolong the service life of the implant.

Description

Porous metal and PEEK composite implanted joint prosthesis and preparation method thereof

Technical Field

The invention relates to the field of manufacturing of orthopedic joints, in particular to an implanted joint prosthesis compounded by porous metal and PEEK and a preparation method thereof.

Background

Aiming at diseases such as joint bone defect, bone lesion, osteonecrosis and the like, the joint prosthesis is mainly repaired by adopting a joint prosthesis implantation fusion mode.

The existing joint prosthesis mainly adopts polyether ether ketone (PEEK) and alloy materials as implant prosthesis, however, the hydrophobicity of the PEEK material causes weak adsorption capacity of cells on the surface and poor osseointegration capacity, the biological inertia of the PEEK material is difficult to realize the combination with host bones, and the initial fixation and long-term stability of the implant are reduced; the alloy material comprises medical metal materials such as titanium alloy, skeleton molybdenum alloy and tantalum alloy, has good biocompatibility and excellent mechanical property, is a common material for orthopedic implants, but has elastic modulus far exceeding that of biological natural bones, is easy to cause stress shielding, causes lack of stress stimulation and force conduction for bone tissue growth, and is not beneficial to biological fixation after implantation; when the metal material is used as a joint implant, the natural bone joint is degraded due to the mismatching of the elastic modulus, and the long-term implantation is adversely affected.

Therefore, the existing joint prosthesis has insufficient stability and biocompatibility, so that the effect is easily lost after the existing joint prosthesis is subjected to daily movement in life for a long time, and the service life of the implant is short.

Disclosure of Invention

The invention aims to provide an implanted joint prosthesis compounded by porous metal and PEEK and a preparation method thereof, and aims to solve the problem that the conventional joint prosthesis is easy to lose efficacy due to insufficient stability and biocompatibility.

In order to achieve the above objects, the present invention provides, in a first aspect, an implant joint prosthesis composed of porous metal and PEEK, including a bone fusion end, an injection-molded sealing plate, and a large pore end, the bone fusion end including a plurality of fixing posts, a micro pore layer, and a support plate, the plurality of fixing posts being fixedly connected to the micro pore layer and located at one side of the micro pore layer, the support plate being fixedly connected to the micro pore layer and located at one side of the micro pore layer remote from the fixing posts, the injection-molded sealing plate being fixedly connected to the support plate and located at one side of the support plate remote from the micro pore layer, the large pore end including a PEEK layer and a large pore layer, the large pore layer being fixedly connected to the injection-molded sealing plate and located at one side of the injection-molded sealing plate remote from the support plate, the PEEK layer being fixedly connected to the large pore layer, and covering the macroporous layer, wherein the PEEK is polyether-ether-ketone.

Wherein the pore size of the micro-pore layer is 0.25-0.8mm, and the porosity is 50% -80%.

Wherein, the diameter of the fixed column is 6-12 mm.

Wherein, the pore size of the macroporous layer is 0.4-1mm, and the porosity is 60% -90%.

In a second aspect, the present invention also provides a method for preparing an implant joint prosthesis by compounding porous metal and PEEK, comprising: designing a microporous layer by adopting gradient porosity based on host bone tissues; designing a plurality of fixing columns according to the strength requirement of bone tissues; manufacturing a bone fusion end based on 3D printing by adopting a metal material; fixing the injection molding sealing plate, the macroporous layer and the bone fusion end to form an implant; manufacturing a PEEK layer mold based on the bone joint model, and placing the implant into the PEEK layer mold for injection molding.

Wherein the metal material comprises Ti₆Al₄V, pure titanium, cobalt-chromium-molybdenum alloy and tantalum alloy.

Wherein the specific steps of designing the microporous layer by adopting gradient porosity based on host bone tissues are as follows: acquiring the pore morphology and the pore size of the host bone fusion region through CT or MRI; the pore distribution is mapped to a microporous layer parameter of the porous implant.

The method comprises the following specific steps of designing a plurality of fixing columns according to the strength requirement of bone tissues: obtaining a three-dimensional model of a host bone; designing the inclination angle of the fixing column based on the three-dimensional model; and designing the diameter and the number of the fixing columns based on the three-dimensional model.

The invention relates to a porous metal and PEEK composite implanted joint prosthesis and a preparation method thereof, wherein a bone fusion end and an injection molding sealing plate are mainly made of titanium alloy, skeleton molybdenum alloy and tantalum alloy, and are matched with holes drilled by host bones through a plurality of fixing columns to provide initial fixation, the micro-pore layer is arranged at one end of the fixing column, so that the elastic modulus of the metal implant can be reduced, stress shielding is avoided, good mechanical stimulation is obtained for host bones, the bone conductivity of the implant is improved, in addition, the communicated micropores provide space for bone tissue to grow in, so that strong biological fixation is formed between the host bone and the implant, the osteogenesis capability of the implant is improved, the support plate is mainly used for being connected with the injection sealing plate so as to isolate the micro-pore layer from the large-pore end during injection molding and prevent PEEK material from seeping into the micro-pore layer during injection molding; the macroporous end is composed of the macroporous layer and the PEEK layer, the macroporous layer is made of titanium alloy, skeleton molybdenum alloy and tantalum alloy, a plurality of holes are formed in the macroporous end, molten PEEK material enters the communicating holes when injection molding is facilitated, and mutual embedded fixation of the two materials is formed. The implanted joint prosthesis has the advantages of good biocompatibility and wear resistance, the micro-pore layer is arranged to facilitate bone growth to form stable fixation, the problems of stress shielding, insufficient bone integration capacity and the like are solved, the bone conductivity and osteogenesis capacity of the implant are effectively improved, the service life of the implant is prolonged, and the problem that the conventional joint prosthesis is easy to lose efficacy due to insufficient stability and biocompatibility is solved.

Drawings

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

FIG. 1 is a block diagram of an implantable joint prosthesis of the present invention in which porous metal is compounded with PEEK;

FIG. 2 is a schematic view of a porous metal and PEEK composite implant joint prosthesis of the present invention applied to an ankle talus implant;

FIG. 3 is a schematic diagram of the injection molding process of a porous metal and PEEK composite joint prosthesis;

FIG. 4 is a flow chart of a method of making a porous metal and PEEK composite implantable joint prosthesis of the present invention;

FIG. 5 is a flow chart of the present invention for designing a microporous layer using gradient porosity based on host bone tissue;

FIG. 6 is a flow chart of the present invention for designing a plurality of fixation posts according to bone tissue strength requirements;

FIG. 7 is a flow chart of the present invention for manufacturing a PEEK layer mold based on a bone joint model;

FIG. 8 is a flow chart of the present invention for injection molding an implant into a PEEK layer mold.

1-bone fusion end, 2-injection molding sealing plate, 3-macropore end, 11-fixing column, 12-micropore layer, 13-supporting plate, 31-PEEK layer, 32-macropore layer, A-host bone, B-implanted bone and C-PEEK layer.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Further, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Referring to fig. 1 and 2, the present invention provides an implant joint prosthesis composed of porous metal and PEEK;

comprises a bone fusion end 1, an injection molding sealing plate 2 and a macropore end 3, wherein the bone fusion end 1 comprises a fixing column 11, a micropore layer 12 and a supporting plate 13, the fixed columns 11 are multiple in number, the fixed columns 11 are fixedly connected with the micro-pore layer 12, and is located at one side of the micro-porous layer 12, the support plate 13 is fixedly connected with the micro-porous layer 12, and is positioned on one side of the micro-pore layer 12 far away from the fixed column 11, the injection molding sealing plate 2 is fixedly connected with the supporting plate 13, and is located on one side of the supporting plate 13 far away from the micro-pore layer 12, the large-pore end 3 comprises a PEEK layer 31 and a large-pore layer 32, the large-pore layer 32 is fixedly connected with the injection molding sealing plate 2, and is located the injection molding sealing plate 2 keep away from one side of backup pad 13, PEEK layer 31 with macroporous layer 32 fixed connection, and cover macroporous layer 32.

In the embodiment, the polyether ether ketone (PEEK) has the advantages of excellent biocompatibility, stable physicochemical properties, strong corrosion resistance and the like, is similar to the elastic modulus of natural bones, can effectively avoid stress shielding, and can avoid the loosening and failure of prostheses; the PEEK material has good friction resistance, can avoid tissue inflammatory reaction of implanted joints caused by abrasion particles, and is widely applied to the field of hard tissue repair and bone implantation B. Medical metal materials such as titanium alloy, skeleton molybdenum alloy and tantalum alloy have good biocompatibility and excellent mechanical properties, are common materials of orthopedic implants, but the elastic modulus of the medical metal materials is far higher than that of biological natural bones, so that stress shielding is easily caused, the growth of bone tissues is lack of stress stimulation and force conduction, and the medical metal materials are not beneficial to biological fixation after implantation; when the metal material is used as a joint implant, the natural bone joint is degraded due to the mismatching of the elastic modulus, and the long-term implantation is adversely affected.

Taking ankle talus implantation as an example, the bone fusion end 1 and the injection sealing plate 2 are mainly made of titanium alloy, bone molybdenum alloy, tantalum alloy, the diameter of the fixation column 11 is 6-12mm, holes drilled through the fixation column 11 and host bone a are matched to provide initial fixation, the micro-pore layer 12 is arranged at one end of the fixation column 11, the pore size of the micro-pore layer 12 is 0.25-0.8mm, and the porosity is 50% -80%, so that the elastic modulus of the metal implant can be reduced, stress shielding can be avoided, the host bone a can obtain good mechanical stimulation, the bone conductivity of the implant can be improved, the communicated micro-pores provide a space for bone tissue growth, strong biological fixation can be formed between the host bone a and the implant, the bone forming capability of the implant can be improved, the supporting plate 13 is mainly used for connecting with the injection sealing plate 2 so as to separate the micro-pore layer 12 and the macro-pore end 3 during injection molding, to avoid the PEEK material from seeping into the microporous layer 12 during injection molding; the macroporous end 3 is composed of the macroporous layer 32 and the PEEK layer 31, the macroporous layer 32 is made of titanium alloy, skeleton molybdenum alloy and tantalum alloy, a plurality of holes are formed in the macroporous layer 32, the size of the holes of the macroporous layer 32 is 0.4-1mm, the porosity is 60% -90%, and molten PEEK materials can conveniently enter the communicated holes during injection molding to form mutual embedded fixation of the two materials.

The implanted joint prosthesis has the advantages of good biocompatibility and wear resistance, the micro-pore layer 12 is arranged to facilitate bone growth to form stable fixation, the problems of stress shielding, insufficient osseointegration capability and the like are solved, the bone conductivity and osteogenesis capability of the implant are effectively improved, the service life of the implant is prolonged, and the problem that the conventional joint prosthesis is easy to lose efficacy due to insufficient stability and biocompatibility is solved.

In a second aspect, referring to fig. 3 to 8, the present invention further provides a method for preparing an implant joint prosthesis composed of porous metal and PEEK, including:

s101, designing a microporous layer 12 by adopting gradient and multiple pores based on host bone A tissues;

the porous gradient design based on natural bone pore distribution is carried out by combining the pore size and porosity of the host bone A tissue as design references, has bionic functions on tissue morphology and mechanical property, and can improve the combining capacity and stability of the implant and the host bone A. The method comprises the following specific steps:

s201, acquiring the pore morphology and pore size of a host bone A fusion region through CT or MRI;

MRI is magnetic resonance imaging, CT is computer tomography, can scan bone tissue through human muscle, thus can obtain the pore form and pore size of host bone A fusion region.

S202 maps the pore distribution to the microporous layer 12 parameters of the porous implant.

The pore morphology and pore size can be extracted by an image processing technology and used as design parameters of the microporous layer 12, so that the microporous layer 12 can be better attached to the host bone A, and the host bone A can grow and be more easily integrated into pores.

S102, designing a plurality of fixing columns 11 according to the strength requirement of bone tissues;

s301, acquiring a three-dimensional model of a host bone A;

since the host bone a of different regions has different shapes, a three-dimensional model is acquired by CT or MRI specifically and then designed specifically.

S302, designing the inclination angle of the fixed column 11 based on the three-dimensional model;

the inclination angle of the fixation post 11 is determined according to the shape of the host bone a, and is generally designed along the length direction of the host bone a to obtain a deeper fixation depth.

S303 designs the diameter and the number of the fixing posts 11 based on the three-dimensional model.

On the basis of the three-dimensional model, the diameter and the number of the fixing columns 11 can be designed according to the strength requirement of the joint and the fixing strength of the single fixing column 11.

S103, manufacturing a bone fusion end 1 based on 3D printing;

the 3D printing may be performed by selective area laser melting (SLM) or Electron Beam Melting (EBM) manufacturing processes, and the metal materials that may be selected include metal materials including Ti6Al4V, pure titanium, cobalt chromium molybdenum alloys, tantalum alloys.

S104, fixing the injection molding sealing plate 2, the macroporous layer 32 and the bone fusion end 1 to form an implant;

and continuously adopting a 3D printing mode, and superposing the designed size of the injection molding sealing plate 2 and the size of the macroporous layer 32 on the bone fusion end 1 to form the implant. Wherein the macroporous layer 32 has a contour similar to the articular surface and is inwardly offset by 1-3 mm. Most of the traditional metal implants are solid structures, or a layer of porous structures is sprayed on the surface of metal through plasma, but the porous connectivity of the layer is poor, and the structure is uncontrollable. The macroporous layer 32 provided by the invention adopts a periodic porous structure, and can obtain a trabecular bone shape similar to the host bone A tissue and matched mechanical properties through Selective Laser Melting (SLM) or Electron Beam Melting (EBM) molding.

S105, manufacturing a PEEK layer mold C based on the bone joint model;

different bone joints in the human body have different characteristics and need to be manufactured specifically.

The method comprises the following specific steps:

s401, acquiring a three-dimensional model of a human body normally implanted bone B through CT or MRI;

s402, designing an upper die cavity of the injection mold according to the three-dimensional model;

s403, manufacturing a mould through machining center equipment;

the manufacturing method mainly comprises rough milling, semi-finish milling and finish milling.

S404 improves the surface roughness through the grinding process.

And grinding or manually polishing the processed die to obtain an inner cavity with the surface roughness of Ra 0.4-0.8. The die steel hardness is 37-52 HRC.

S106, the implant is placed into a PEEK layer mold C for injection molding.

The method comprises the following specific steps:

s501, placing the implant into a PEEK layer mold C;

s502, adding a PEEK material through an injection molding port under the conditions of high temperature and high pressure, wherein the temperature is 350-380 ℃, the injection pressure is 7-16 MPa, and the holding pressure is 5-15 MPa;

s503, cooling for 1-2min, and finishing the injection molding process.

According to the preparation method of the porous metal and PEEK composite implanted joint prosthesis, polyether-ether-ketone (PEEK) has excellent biocompatibility and wear resistance and is similar to the elastic modulus of natural bones; the microporous layer 12 provides interconnected pores for the ingrowth of bone tissue, is beneficial to nutrient exchange and vascular ingrowth and has excellent osteogenic performance. According to the invention, through a porous design, a 3D printing process and an injection molding process, the advantages of two materials are fully combined, the problems of insufficient stress shielding and osseointegration capability and the like are avoided, the osteoconductivity and osteogenesis capability of the implant are effectively improved, and the problem that the conventional joint prosthesis is easy to lose efficacy due to insufficient stability and biocompatibility is solved. The manufacturing cost can be reduced by performing mass manufacturing after one design is completed to be used by more people.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. a composite implanted joint prosthesis of porous metal and PEEK, is characterized in that,

Including a bone fusion end, an injection molding sealing plate and a large pore end, the bone fusion end includes a fixed column, a microporous layer and a support plate, the number of the fixed column is multiple, and the plurality of the fixed column and the micropore The layers are fixedly connected and located on one side of the microporous layer, the support plate is fixedly connected with the microporous layer, and is located on the side of the microporous layer away from the fixed column, and the injection molding sealing plate is connected to the microporous layer. The support plate is fixedly connected and is located on the side of the support plate away from the microporous layer, the macroporous end includes a PEEK layer and a macroporous layer, and the macroporous layer is fixedly connected to the injection molding sealing plate, and located on the side of the injection molding sealing plate away from the support plate, the PEEK layer is fixedly connected with the macroporous layer and covers the macroporous layer, and PEEK is polyetheretherketone.

2. the implanted joint prosthesis of a kind of porous metal and PEEK composite as claimed in claim 1, is characterized in that,

The pore size of the microporous layer is 0.25-0.8 mm, and the porosity is 50%-80%.

3. the implanted joint prosthesis of a kind of porous metal and PEEK composite as claimed in claim 1, is characterized in that,

The diameter of the fixed column is 6-12 mm.

4. a kind of implanted joint prosthesis composite of porous metal and PEEK as claimed in claim 1, is characterized in that,

The pore size of the macroporous layer is 0.4-1 mm, and the porosity is 60%-90%.

5. a preparation method of the composite implanted joint prosthesis of porous metal and PEEK, is characterized in that,

Including the use of gradient porous design microporous layer based on host bone tissue;

Design multiple fixation columns according to bone tissue strength requirements;

Using metal materials to manufacture bone fusion ends based on 3D printing;

Fix the injection molding sealing plate and the macroporous layer with the bone fusion end to form an implant;

Manufacture PEEK layer mold based on bone joint model;

The implants were placed into PEEK layer molds for injection molding.

6. the preparation method of the composite implanted joint prosthesis of a kind of porous metal and PEEK as claimed in claim 5, is characterized in that,

The metal materials include Ti ₆ Al ₄ V, pure titanium, cobalt-chromium-molybdenum alloy, and tantalum alloy.

7. the preparation method of the composite implanted joint prosthesis of a kind of porous metal and PEEK as claimed in claim 5, is characterized in that,

The specific steps of designing the microporous layer based on the host bone tissue using gradient porosity are:

Obtain the pore morphology and pore size of the host bone fusion area by CT or MRI;

This pore distribution is mapped to the microporous layer parameters of the porous implant.

8. the preparation method of the composite implanted joint prosthesis of a kind of porous metal and PEEK as claimed in claim 5, is characterized in that,

The specific steps of designing a plurality of fixing columns according to the strength requirement of the bone tissue are:

Obtain a 3D model of the host bone;

Design the inclination angle of the fixed column based on the 3D model;

Design the diameter and number of fixed columns based on the 3D model.