Double-component ceramic surface hip prosthesis

Abstract

The invention relates to a double-component hip prosthesis with a ceramic surface. The double-component ceramic surface hip prosthesis comprises an acetabulum outer cup and a surface ball head made of a ceramic material, wherein a femoral stem is arranged in an inner cavity of the surface ball head; the surface ball head is embedded in the acetabular outer cup and can rotate relative to the acetabular outer cup, the outer wall face of the acetabular outer cup and the inner wall face of the surface ball head are both covered with bone trabecula layers in a fusion covering mode through the coating preparation method, and the bone trabecula layers are in a net shape. Therefore, the problems that in the prior art, metal chippings are generated on a friction interface of a surface hip joint prosthesis, the prosthesis is prone to loosening, an outer cup is prone to deformation, and the effect that the outer cup induces bone cells to grow in is poor can be solved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of artificial joints, and more particularly, to a two-component ceramic surface hip prosthesis. Background Art

[0002] As a surgical implant for replacing the diseased part of the human hip joint, the surface hip prosthesis is designed to provide an effective solution that can both restore function and reduce complications. Traditional surface hip prostheses mainly consist of an outer cup prosthesis for the acetabulum and a femoral head prosthesis that fits over the human femoral head. Compared with traditional total hip replacement surgery, such prostheses can effectively reduce postoperative complications and revision rates, and retain more bone mass for future revision surgeries.

[0003] However, although surface hip replacement systems such as the Birmingham Hip Resurfacing System of Smith & Nephew and the CONSERVE Total Hip System of Shanghai MicroPort Orthopedics Co., Ltd. are widely used in the market, they still have some significant limitations. These products are usually made of cobalt-chromium-molybdenum alloy and are configured with a "metal-on-metal" joint wear interface. Although this structure improves the durability of the prosthesis to a certain extent, it also brings the risk of increased metal ion concentration in the blood and the problem that metal debris generated by friction may cause loosening around the prosthesis.

[0004] Specifically, the main challenges faced by current surface hip prostheses include:

[0005] 1. Friction interface problem: The existing "metal-on-metal" wear interface increases the risk of metal ion levels in the blood and may cause inflammatory reactions and loosening of the tissue around the prosthesis due to the presence of metal debris.

[0006] 2. Risk of outer cup deformation: In order to retain the patient's femoral head, there are certain limitations in the selection of the outer cup thickness during the design process, which may increase the risk of deformation of the ceramic outer cup after implantation into the human body.

[0007] 3. Insufficient coating bonding strength: The current surface coating technology has the problem of low bonding strength, which is easy to fall off and cause infection. In addition, the pore structure of the coating is difficult to control, the pore diameter is small and the porosity is low, which is not conducive to the growth of bone cells and affects long-term stability.

[0008] Based on the above analysis, although existing surface hip prostheses have addressed some clinical needs, there are still many deficiencies in practical applications. To overcome these problems, there is an urgent need to develop a new design solution that can solve the problems in the prior art, such as the generation of metal debris at the friction interface of surface hip prostheses, which easily leads to prosthesis loosening, deformation of the outer cup, and poor effect of the outer cup inducing osteocyte ingrowth. Summary of the Invention

[0009] The object of the present disclosure is to provide a two-component ceramic surface hip prosthesis, which can solve the problems in the prior art, such as the generation of metal debris at the friction interface of surface hip prostheses, which easily leads to prosthesis loosening, deformation of the outer cup, and poor effect of the outer cup inducing osteocyte ingrowth.

[0010] To achieve the above object, the present disclosure provides a two-component ceramic surface hip prosthesis, including an acetabular outer cup and a surface ball head made of ceramic material. A femoral stem is provided in the inner cavity of the surface ball head; the surface ball head is embedded in the acetabular outer cup and can rotate relative to the acetabular outer cup. Among them, a trabecular bone layer is cladded on the outer wall surface of the acetabular outer cup and the inner wall surface of the surface ball head by using the coating preparation method described below, and the trabecular bone layer is reticular.

[0011] In a possible design, the porosity of the trabecular bone layer is 50-90%, and the pore diameter is 100-400 μm.

[0012] In a possible design, the thickness of the trabecular bone layer is 1.4-1.6 mm.

[0013] In a possible design, the trabecular bone layer is provided on both the outer wall surface and the inner wall surface of the surface ball head.

[0014] In a possible design, a reticular reinforcing rib is provided on the outer surface of the acetabular outer cup.

[0015] In a possible design, a plurality of grooves are provided on the femoral stem along its circumferential direction.

[0016] In a possible design, a strip-shaped limiting groove is provided on the inner wall surface of the surface ball head, and the limiting groove extends along the vertex of the surface ball head;

[0017] / and, a plurality of the limiting grooves are provided and are evenly spaced along the circumferential direction of the femoral head;

[0018] / and, the groove wall of the limiting groove is an arc surface.

[0019] In a possible design, both the acetabular outer cup and the surface ball head are made of ceramic material.

[0020] In a possible design, the material of the ceramic material includes α-aluminum oxide powder and zirconia powder.

[0021] In a possible design, the purity of the α-aluminum oxide powder is ≥99.9%, and the particle size of the α-aluminum oxide powder is submicron to nanoscale;

[0022] In a possible design, yttrium oxide accounts for 3% of the mass of zirconia.

[0023] In a possible design, the material of the ceramic material further includes strontium oxide and / or chromium oxide.

[0024] The present disclosure also provides a method for preparing a coating of a dual-component ceramic surface hip prosthesis. The coating preparation method is used for a dual-component ceramic surface hip prosthesis, and the trabecular layer is the coating; wherein, the coating includes a base layer cladded on a substrate, a transition layer cladded on the base layer, and a working layer cladded on the transition layer. The transition layer is configured to be at least one layer. The preparation method includes:

[0025] Pre-treat the substrate;

[0026] Use a synchronous laser cladding device to clad titanium-based alloy powder on the surface of the cladding substrate to form a base layer;

[0027] Use a synchronous laser cladding device to clad titanium-based alloy powder on the surface of the base layer to form the transition layer;

[0028] Use a synchronous laser cladding device to clad the titanium-based alloy powder on the surface of the transition layer to form the working layer;

[0029] Perform heat preservation treatment on the cladding substrate after laser cladding strengthening and then cool it.

[0030] In a possible design, the synchronous laser cladding device is preset with cladding process parameters. The cladding process parameters include: laser power, cladding speed, cladding basic parameters, powder feeding amount, and protective gas pressure. Among them, the cladding basic parameters include: cladding layer thickness, cladding path spacing, cladding layer spacing, number of cladding layers, and cladding layer width.

[0031] In a possible design, the laser power is at least 1 kW; the cladding speed is less than 200 mm / s;

[0032] The cladding layer thickness is 0.15 - 1.0 mm; the cladding path spacing is 0.5 - 0.9 mm; the cladding layer spacing is 0.1 - 0.3 mm; the number of cladding layers is 1 - 4 layers, and the cladding layer width is 0.2 - 0.5 mm;

[0033] The powder feeding rate is 6 g / min to 12 g / min;

[0034] The protective gas pressure value is 1.8 to 2.2 bar.

[0035] In a possible design, the laser power is 1.5 kW; the cladding speed is 50 mm / s;

[0036] The thickness of the cladding layer is 0.25 mm; the cladding path spacing is 0.5 mm; the cladding layer spacing is 0.2 mm; the number of cladding layers is 3 layers, the width of the cladding layer is 0.2 mm; the powder feeding rate is 8 g / min; the protective gas pressure value is 2 bar.

[0037] In a possible design, the protective gas is argon.

[0038] In a possible design, the coating on the acetabular outer cup starts to be coated from the 40 mm ring diameter of the acetabular outer cup, and increases in size by 2 mm until the coating stops at the 70 mm ring diameter; the coating on the surface ball head starts to be coated from the 35 mm ring diameter of the surface ball head, and increases in size by 2 mm until the coating stops at the 65 mm ring diameter.

[0039] In a possible design, the titanium-based alloy powder is configured as titanium 6 aluminum 4 vanadium alloy powder.

[0040] Through the above technical solution, the design of the trabecular coating simulates the human body's own bone structure, improving the biocompatibility between the prosthesis and the host bone. This trabecular structure allows bone tissue to grow in, which can promote the growth of acetabular bone tissue into the internal structural units, thus enabling the tight fusion of the prosthesis with the surrounding bone tissue and increasing long-term stability. And using a ceramic material as the surface ball head, due to its high hardness and excellent wear resistance, it can reduce the friction and wear between prostheses and extend the service life of the prosthesis. Thereby, the risk of postoperative complications such as prosthesis loosening and dislocation is reduced, which is beneficial to the patient's recovery. In this way, the patient's pain symptoms can be significantly improved, the joint function can be restored, and the quality of daily life can be improved.

[0041] In the present disclosure, since the trabecular bone layer is prepared by the coating preparation method of the second aspect, the resulting dual-component ceramic surface hip prosthesis can keep the acetabular anatomical rotation center stable based on its structural design, avoiding the situation of central offset, thereby improving the stability of the joint. In addition, since the dual-component ceramic surface hip prosthesis has been subjected to cladding treatment when it is implanted, due to the existence of the set reticular trabecular bone, the differentiation efficiency of bone marrow stem cells can be improved, and at the same time, it has a positive effect on the regeneration of soft tissues. At the same time, the rough and porous surface of the reticular trabecular bone can well induce the generation of heterotopic bone, and can improve the adhesion, proliferation and differentiation ability of osteoblasts. In addition, based on the surface roughness of the formed coating on the macroscopic scale, micro-motion can be greatly reduced, which is beneficial to bone ingrowth.

[0042] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation section. Brief Description of the Drawings

[0043] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0044] Figure 1 is a three-dimensional structural schematic diagram of the dual-component ceramic surface hip prosthesis from one perspective, where the trabecular bone is not shown;

[0045] Figure 2 is a three-dimensional structural schematic diagram of the dual-component ceramic surface hip prosthesis from another perspective, where the trabecular bone is not shown;

[0046] Figure 3 is the tensile strength test chart of part A1 in Example 1;

[0047] Figure 4 is the tensile strength test chart of part A2 in Example 2;

[0048] Figure 5 is the tensile strength test chart of part A3 in Example 3;

[0049] Figure 6 is the tensile strength test chart of part A4 in Example 4;

[0050] Figure 7 is the cross-sectional view obtained after the tensile test of parts A1 and A2. Among them, the part in the upper group is A1, and the part in the lower group is A2;

[0051] Figure 8 is the cross-sectional view obtained after the tensile test of parts A3 and A4. Among them, the part in the upper group is A3, and the part in the lower group is A4;

[0052] Figure 9 It is a schematic diagram of the structure of trabecular bone, where Lt refers to the spacing of the cladding paths (i.e., the groove width of the trabecular bone in the circumferential direction);

[0053] Figure 10 It is a schematic diagram of the structure of trabecular bone, where Lc refers to the layer spacing of the cladding (i.e., the spacing of the trabecular bone of adjacent layers in the diameter direction);

[0054] Figure 11 It is a schematic diagram of the structure of a two-component ceramic surface hip prosthesis, where the coating cladded on the outer acetabular cup is the trabecular bone.

[0055] Explanation of the reference numerals

[0056] 1 - Outer acetabular cup, 2 - Surface ball head, 3 - Femoral stem, 4 - Trabecular bone layer, 5 - Reinforcing rib, 6 - Limiting groove, 7 - Groove. Detailed implementation manners

[0057] The following will describe in detail the specific implementation manners of the present disclosure with reference to the accompanying drawings.

[0058] According to the first aspect of the present disclosure, a two-component ceramic surface hip prosthesis is provided, where Figures 1 to 11 One of the specific implementation manners is shown.

[0059] The two-component ceramic surface hip prosthesis includes an outer acetabular cup 1 and a surface ball head 2 made of ceramic material. A femoral stem 3 is provided in the inner cavity of the surface ball head 2; the surface ball head 2 is embedded in the outer acetabular cup 1 and can rotate relative to the outer acetabular cup 1. Among them, the outer wall surface of the outer acetabular cup 1 and the inner wall surface of the surface ball head 2 are both cladded with a trabecular bone layer 4. The trabecular bone layer 4 is in a net shape, which is beneficial to increasing the ingrowth area of bone tissue, so that it can better combine with the bone, and improve the stability of the implant.

[0060] Through the above technical solution, the design of the trabecular bone coating simulates the human body's own bone structure and improves the biocompatibility between the prosthesis and the host bone. This trabecular bone structure allows bone tissue to grow in, and can promote the ingrowth of acetabular bone tissue into the internal structure unit, so as to closely integrate the prosthesis with the surrounding bone tissue and increase the long-term stability. And using ceramic material as the surface ball head 2, due to its high hardness and excellent wear resistance, it can reduce the friction and wear between the prostheses and extend the service life of the prosthesis. Thus, the risk of postoperative complications such as prosthesis loosening and dislocation is reduced, which is beneficial to the patient's recovery. In this way, the pain symptoms of the patient can be significantly improved, the joint function can be restored, and the quality of daily life can be improved.

[0061] The application process of this dual-component ceramic surface hip prosthesis is as follows: The patient is comprehensively evaluated, including imaging examinations (such as X-ray films or CT scans), to determine the most suitable prosthesis size and type. In addition, necessary laboratory tests are carried out to ensure that the patient is suitable for surgery. Local anesthesia or general anesthesia is selected according to the specific situation of the patient. An incision is made near the hip joint, and the muscles and other soft tissues are moved to expose the acetabulum. Special tools are used to clean and shape the acetabulum to provide a stable foundation for the acetabular outer cup 1. Then, holes are drilled in the acetabulum and screws or other fixation devices may be used to enhance the stability of the acetabular outer cup 1. The acetabular outer cup 1 with a trabecular coating is accurately placed in the prepared acetabulum position and ensured to be firmly fixed. The damaged femoral head is resected, and the femoral neck is prepared to receive the surface ball head 2. The surface ball head 2 containing the femoral head is inserted into the acetabular outer cup 1 to ensure a good matching relationship between the two. The incision is closed, the joint mobility is checked, and it is confirmed whether the prosthesis is correctly installed and functions normally.

[0062] In the present disclosure, since the trabecular layer 4 is prepared by the coating preparation method of the second aspect, the dual-component ceramic surface hip prosthesis thus made can keep the anatomical rotation center of the acetabulum stable based on its structural design, avoiding the situation of central offset, thereby improving the stability of the joint. In addition, since the dual-component ceramic surface hip prosthesis has been subjected to cladding treatment when implanted, based on the presence of the set reticular trabeculae, it can improve the differentiation efficiency of bone marrow stem cells and has a positive effect on the regeneration of soft tissues. At the same time, the rough and porous surface of the reticular trabeculae can well induce the generation of heterotopic bone and can improve the adhesion, proliferation, and differentiation abilities of osteoblasts. In addition, based on the surface roughness of the formed coating at the macroscopic scale, the fretting can be greatly reduced, which is beneficial to bone ingrowth.

[0063] In a possible design, the porosity of the trabecular layer 4 is 50-90%, which is beneficial to promoting bone tissue ingrowth. The trabecular layer 4 can provide sufficient space for bone cell migration, proliferation, and differentiation, thereby promoting the growth of new bone tissue. The pore size is 100-400 μm. Such a setting is beneficial to the penetration of bone cells and ensures good mechanical support to prevent the structure from being too fragile.

[0064] By setting appropriate pore sizes and porosities, mechanical properties similar to those of human bones can be provided, the stress shielding effect can be reduced, and the long-term stability of the implant can be improved. In this way, both the good integration of bone tissue can be promoted and the necessary mechanical strength can be maintained, which is of great significance for ensuring the successful implantation and long-term stability of the prosthesis. In addition, such a design also reflects the effort direction of modern biomaterial engineering to optimize the performance of implants.

[0065] In a possible design, the thickness of the trabecular layer 4 is 1.4 - 1.6 mm. The appropriate thickness helps to maintain the structural strength of the implant, ensuring that it can withstand the mechanical loads during daily activities. In this way, the bone tissue can be stably combined with the trabecular layer 4, improving the compressive strength and fatigue life of the implant, thereby reducing the problems that may occur during long-term use.

[0066] In the present disclosure, the thickness of the trabecular layer 4 is 1.5 mm, which can balance biocompatibility and mechanical properties while meeting the requirements of clinical applications.

[0067] In a possible design, the outer wall surface and the inner wall surface of the surface ball head 2 are both provided with the trabecular layer 4. Setting the trabecular layer 4 on the inner wall surface can provide better fixation support for the femoral head or other internal components, which is beneficial to promoting the direct combination between the prosthesis and the host bone. In this way, a surface closer to the natural bone environment can be provided, increasing the biocompatibility between the prosthesis and the surrounding bone tissue and reducing the risk of foreign body reaction. By simultaneously setting the trabecular layer 4 on the outer wall surface and the inner wall surface, a multi-level bone integration effect from the outside to the inside can be achieved, further enhancing the overall stability and reliability of the prosthesis.

[0068] In a possible design, the outer surface of the acetabular cup 1 is provided with a reticular reinforcing rib 5, which can enhance the overall structural stability of the acetabular cup 1, effectively disperse the loads brought by daily activities, reduce local stress concentration, and thus reduce the risk of prosthesis loosening or failure. Based on the reticular structure of the reinforcing rib 5, the surface area of contact between the acetabular cup 1 and the host bone can be effectively increased, promoting the ingrowth of bone cells and enhancing the biofixation effect. The structure of the reticular reinforcing rib 5 can also produce an effect similar to the trabecular structure inside the human bone, providing a more suitable growth environment for bone cells and enhancing the biocompatibility between the implant and the host bone.

[0069] It should be noted that for the term "and / or" appearing in this article, it is merely a description of the association relationship between associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, B exists alone, and both A and B exist simultaneously. For the term " / and" appearing in this article, it describes another association relationship between associated objects, indicating that there can be two relationships. For example, A / and B can represent: A exists alone, and both A and B exist alone. Additionally, for the character " / " that may appear in this article, generally it represents that the front and rear associated objects are in an "or" relationship.

[0070] In the present disclosure, a plurality of grooves 7 are provided on the femoral stem 3, and the grooves 7 are arranged along its circumferential direction. The provision of the grooves 7 can guide bone tissue to combine with the femoral stem 3 from different positions, and can prevent the surface ball head 2 from rotating unnecessarily relative to the femur to a certain extent, which is beneficial to maintaining the long-term stability of the prosthesis.

[0071] In a possible design, a strip-shaped limiting groove 6 is provided on the inner wall surface of the surface ball head 2, and the limiting groove 6 extends along the vertex of the surface ball head 2. With such a setting, bone tissue can combine with the surface ball head 2 from different positions, which can effectively prevent the surface ball head 2 from rotating, thereby maintaining the long-term stability of the prosthesis, especially under the condition of repeated stress. The limiting groove 6 increases the contact area and friction force between the internal components and the surface ball head 2, thereby enhancing the stability of the overall structure.

[0072] In the present disclosure, a plurality of limiting grooves 6 are provided and are evenly spaced along the circumferential direction of the femoral head. This can make the contact between the femoral head and the acetabular cup more uniform, help to disperse the load, reduce stress concentration in local areas, thereby reducing the wear rate and extending the service life of the prosthesis. Each limiting groove 6 can serve as a fixed reference point to ensure the correct position of the femoral head in the acetabulum and avoid wear or instability caused by improper rotation. During the movement of the human body, the human joints need to bear complex dynamic loads. The evenly spaced arrangement of the limiting grooves 6 in the circumferential direction can help to better simulate the behavior of natural joints, enabling the prosthesis to respond more naturally to various forces in daily activities.

[0073] In the present disclosure, the groove wall of the limiting groove 6 is an arc surface. The design of the arc-shaped groove wall can increase the contact area between the bone tissue and the inner wall surface of the surface ball head 2, thereby increasing the actual contact area with the internal components (such as the femoral head), improving the stability of the overall structure, and providing a smoother movement trajectory under dynamic loads. Compared with the design of right angles or sharp edges, the arc-shaped groove wall can more effectively disperse the acting force, reduce local stress concentration, avoid premature failure due to material fatigue, and thus ensure the service life of the prosthesis.

[0074] In a possible design, the ceramic material includes α-aluminum oxide powder and zirconia powder. α-aluminum oxide (α-Al2O3) has the characteristics of high hardness, wear resistance, high temperature resistance, good chemical stability and electrical insulation. As a raw material, it can provide high strength and hardness while maintaining a low coefficient of thermal expansion, enabling it to maintain dimensional stability. In addition, α-aluminum oxide has a very high corrosion resistance, which enables the prosthesis made of it to be used for a long time in a harsh environment.

[0075] Zirconia (ZrO2) is a very hard and tough ceramic material with high fracture toughness and relatively high flexural strength. By adding zirconia to the matrix, the toughness of the composite material can be significantly improved because zirconia undergoes a transformation toughening mechanism under stress, that is, energy is absorbed during the process of t-ZrO2 transforming into m-ZrO2, thus preventing crack propagation. In addition, zirconia also has good thermal shock resistance and can withstand large temperature differences during rapid heating and cooling without cracking.

[0076] In the present disclosure, α-alumina is used in combination with zirconia. Yttrium oxide can form a solid solution by substituting Zr 4+ ions in the zirconia lattice, thereby stabilizing the tetragonal phase of zirconia, suppressing its spontaneous phase transformation at low temperatures, improving the toughness and strength of the ceramic material, not only enhancing the wear resistance of the prosthesis, but also strengthening its mechanical strength and toughness, making it more suitable for the treatment needs of young and active patients.

[0077] In a possible design, the purity of the α-alumina powder is ≥99.9%, which helps to reduce defects and impurities inside the material, thereby improving its chemical stability and resisting the erosion of various chemical media. The particle size of the α-alumina powder is submicron to nanoscale. The α-alumina powder with submicron to nanoscale particle size has a larger specific surface area, which can improve the activity of the material, promote the diffusion between particles during sintering, and thus obtain a denser ceramic product. The increase in density can improve the mechanical strength and fatigue resistance of the acetabular outer cup 1 and the surface ball head 2.

[0078] In a possible design, yttrium oxide accounts for 3% of the mass of zirconia. By mixing a salt solution containing zirconium and yttrium and then adding a precipitant, the two metal ions are simultaneously precipitated, and the required powder is obtained through steps such as filtration, drying, and calcination. This method involves the hydrolysis and polymerization reactions of metal alkoxides or their derivatives in solution to form a three-dimensional network structure gel, and then nano-scale oxide powders are obtained through drying and calcination.

[0079] Under high temperature and high pressure conditions, adding 3% molar ratio of yttrium oxide can effectively stabilize the tetragonal phase of zirconia, thereby improving the fracture toughness and flexural strength of the material and maintaining the stability of the structure and properties in a high-temperature environment.

[0080] In a possible design, the ceramic material further includes strontium oxide. The addition of strontium oxide helps to form a liquid phase, which can reduce the sintering temperature and accelerate the rearrangement and densification process between particles, thereby changing the diffusion mechanism during sintering and promoting more uniform grain growth, thus improving the density and mechanical strength of the final product. In this way, the acetabular outer cup 1 and the surface ball head 2 prepared therefrom can have better comprehensive mechanical properties, including but not limited to higher fracture toughness and impact resistance. In addition, the presence of the solid solution may also improve the thermal expansion coefficient matching of the material and reduce the stress concentration problem caused by temperature changes.

[0081] Strontium oxide can not only be used alone as an additive, but also form a solid solution with other oxides such as alumina. For example, the SrO-Al2O3 solid solution can replace pure alumina to a certain extent, providing higher chemical stability and thermal stability, while reducing the volume change caused by phase transformation.

[0082] In one embodiment, the ceramic material further includes chromium oxide. Chromium oxide (Cr2O3) reduces the sintering temperature and shortens the sintering time, helps to form a more uniform and dense microstructure, is beneficial to increasing the density of the material, also reduces pores and other defects, and further enhances the mechanical properties of the material. By forming a solid solution with the matrix material or the second-phase strengthening mechanism, chromium oxide can significantly increase the hardness, wear resistance and fracture toughness of the ceramic material. In addition, due to its high melting point and good thermal stability, chromium oxide can also improve the thermal shock stability of the material, making it not easy to crack during rapid heating and cooling cycles.

[0083] In yet another embodiment, the ceramic material further includes strontium oxide and chromium oxide. As an additive, strontium oxide can change the diffusion state during sintering, promote more uniform grain growth, and thus refine the grain size in the ceramic material. And strontium oxide can reduce the sintering temperature and accelerate the rearrangement and densification process between particles, thereby improving the density and mechanical strength of the final product. The ability of strontium oxide to form a solid solution with other oxides such as alumina can replace pure alumina to a certain extent and better control the microstructure of the ceramic material, such as refining grains and reducing porosity, and improving the material density and mechanical properties.

[0084] According to a second aspect of the present disclosure, a method for preparing a coating for a two-component ceramic surface hip prosthesis is provided. The coating preparation method is used for a two-component ceramic surface hip prosthesis, and the trabecular layer 4 serves as the coating. Among them, the coating includes a base layer cladded on the substrate, a transition layer cladded on the base layer, and a working layer cladded on the transition layer. The transition layer is configured to be at least one layer. The preparation method includes: pretreating the substrate; using a synchronous laser cladding device to clad a titanium-based alloy powder on the surface of the cladding substrate to form a base layer; using a synchronous laser cladding device to clad a titanium-based alloy powder on the surface of the base layer to form a transition layer; using a synchronous laser cladding device to clad a titanium-based alloy powder on the surface of the transition layer to form a working layer; performing heat preservation treatment on the cladding substrate after laser cladding strengthening and then cooling. With such a design, the cladded coating can have a porosity greater than 30%, which is beneficial to the ingrowth of the host bone after the prosthesis implantation, thereby improving the stability of the prosthesis.

[0085] In a possible design, the synchronous laser cladding device is preset with cladding process parameters, and the cladding process parameters include: laser power, cladding speed, cladding basic parameters, powder feeding amount, and protective gas pressure. Among them, the cladding basic parameters include: cladding layer thickness, cladding path spacing, cladding layer spacing, number of cladding layers, and cladding layer width.

[0086] Specifically, the laser power is at least 1 kW; the cladding speed is less than 200 mm / s; the cladding layer thickness is 0.15 - 1.0 mm; the cladding path spacing is 0.5 - 0.9 mm; the cladding layer spacing is 0.1 - 0.3 mm; the number of cladding layers is 1 - 4 layers, the cladding layer width is 0.2 - 0.5 mm; the powder feeding amount is 6 g / min - 12 g / min; the protective gas pressure value is 1.8 - 2.2 bar.

[0087] In a possible design, the laser power is 1.5 kW; the cladding speed is 50 mm / s; the cladding layer thickness is 0.25 mm; the cladding path spacing is 0.5 mm; the cladding layer spacing is 0.2 mm; the number of cladding layers is 3 layers, the cladding layer width is 0.2 mm; the powder feeding amount is 8 g / min; the protective gas pressure value is 2 bar.

[0088] In a possible design, the protective gas is argon; the titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder.

[0089] In a possible design, the coating on the acetabular outer cup 1 starts to be coated from the 40 mm ring diameter of the acetabular outer cup 1 and increases in size by 2 mm until the coating stops at the 70 mm ring diameter; the coating on the surface ball head 2 starts to be coated from the 35 mm ring diameter of the surface ball head 2 and increases in size by 2 mm until the coating stops at the 65 mm ring diameter.

[0090] The coating includes a base layer cladded on the substrate, a transition layer cladded on the base layer, and a working layer cladded on the transition layer, and the transition layer is configured to be at least one layer. It can be understood that the coating is formed as the following trabecular layer 4. Hereinafter, the application of this preparation method to a two-component ceramic surface hip prosthesis will be taken as an example to detail the present disclosure. Among them, the maximum diameter of the substrate (the two-component ceramic surface hip prosthesis without a coating) is 72 mm.

[0091] In the present disclosure, the titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder and cladded onto the surface of a part (a substrate made of ceramic material) by using the coating preparation method of the second aspect, so as to measure the coating strength of the part after cladding. Specifically, two parts are selected, one with a cladded coating and the other without a cladded coating. After the two parts are fusion-bonded, a combined part for the test is obtained. Then, both ends of the combined part are respectively clamped by a tensile strength testing machine, and in accordance with ASTM F1147 "Standard Test Method for Tension Testing of Calcium Phosphate and Metallic Coatings", the combined part is broken from the bonding surface, and the coating tensile strength is calculated.

[0092] Example 1:

[0093] In this example, the cladding process parameters in the synchronous laser cladding device are: laser power is 1.5 kW; cladding speed is 50 mm / s; cladding layer thickness is 0.25 mm; cladding path spacing is 0.5 mm; cladding layer spacing is 0.1 mm; number of cladding layers is 4 layers, and cladding layer width is 0.2 mm.

[0094] The titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder; powder feeding rate is 8 g / min; protective gas pressure value is 2 bar. Among them, the protective gas is argon, and the titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder.

[0095] Example 2:

[0096] In this example, the cladding process parameters in the synchronous laser cladding device are: laser power is 1.5 kW; cladding speed is 55 mm / s; cladding layer thickness is 0.3 mm; cladding path spacing is 0.6 mm; cladding layer spacing is 0.2 mm; number of cladding layers is 3 layers, and cladding layer width is 0.3 mm.

[0097] The titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder; powder feeding rate is 9 g / min; protective gas pressure value is 2 bar. Among them, the protective gas is argon, and the titanium-based alloy powder is configured as a titanium 6 aluminum 4 vanadium alloy powder.

[0098] Example 3:

[0099] In this embodiment, the cladding process parameters in the synchronous laser cladding device are as follows: the laser power is 1.5 kW; the cladding speed is 60 mm / s; the cladding layer thickness is 0.4 mm; the cladding path spacing is 0.7 mm; the cladding layer spacing is 0.2 mm; the number of cladding layers is 3, and the cladding layer width is 0.4 mm.

[0100] The titanium-based alloy powder is configured as Ti-6Al-4V alloy powder; the powder feeding rate is 9 g / min; the protective gas pressure value is 2 bar. Among them, the protective gas is argon, and the titanium-based alloy powder is configured as Ti-6Al-4V alloy powder.

[0101] Example 3:

[0102] In this embodiment, the cladding process parameters in the synchronous laser cladding device are as follows: the laser power is 1.5 kW; the cladding speed is 55 mm / s; the cladding layer thickness is 0.35 mm; the cladding path spacing is 0.6 mm; the cladding layer spacing is 0.25 mm; the number of cladding layers is 3, and the cladding layer width is 0.35 mm.

[0103] The titanium-based alloy powder is configured as Ti-6Al-4V alloy powder; the powder feeding rate is 9 g / min; the protective gas pressure value is 2 bar. Among them, the protective gas is argon, and the titanium-based alloy powder is configured as Ti-6Al-4V alloy powder.

[0104] Example 4:

[0105] In this embodiment, the cladding process parameters in the synchronous laser cladding device are as follows: the laser power is 1.5 kW; the cladding speed is 55 mm / s; the cladding layer thickness is 0.35 mm; the cladding path spacing is 0.65 mm; the cladding layer spacing is 0.3 mm; the number of cladding layers is 3, and the cladding layer width is 0.35 mm.

[0106] The powder feeding rate is 8 g / min; the protective gas pressure value is 2 bar. Among them, the protective gas is argon, and the titanium-based alloy powder is configured as Ti-6Al-4V alloy powder.

[0107] Select a cladded part from Example 1, and then bond it with an uncladded part to obtain the corresponding part marked as A1 (see Figure 3 ). Select a cladded part from Example 2, and then bond it with an uncladded part to obtain the corresponding combined part marked as A2 (see Figure 4 ); select a cladded part from Example 3, and then bond it with an uncladded part to obtain the corresponding part marked as A3 (see Figure 5 ), select a cladded part from Example 4, and then bond it with an uncladded part to obtain the corresponding part marked as A4 (see Figure 6The combined parts. It should be noted that according to the standard YY 0118-2016 "Hip Prosthesis for Joint Replacement Implants", the tensile strength requirement of the parts is greater than 22 MPa.

[0108] The laser cladding coating mechanical tensile strength tests were respectively carried out on the combined parts A1, A2, A3 and A4, and the following data were obtained.

[0109]

[0110] Table 1---Table of Test Results of Tensile Strength of Parts

[0111] Referring to Table 1 and Figures 3 to 6 it can be seen that among the combined parts A1 (refer to Figure 7 ), A2 (refer to Figure 7 ), A3 (refer to Figure 8 ), and A4 (refer to Figure 8 ), the fracture cross-sections are all located in the cladding layer, that is, the fusion bonding surface between the two parts, rather than the fracture between the cladding layer and the part. The above tests can all prove that: the bonding strength between the coating (trabecular bone layer) and the part (substrate) is greater than the strength of the fusion layer itself. Therefore, in this way, the bonding strength between the coating and the substrate is relatively high, avoiding the situation of coating peeling off during use. At the same time, it can also confirm that the substrate is not easy to appear debris and other situations. After the mechanical tensile strength tests of the cladding coatings were respectively carried out on 4 groups of cladded parts, the mechanical strength of the cladded parts is much higher than the industry standard value, and the test results all meet the standard ASTM F1147. The coating quality of the cladded products is qualified, and the stability is all above 97%.

[0112] To sum up, through the coating preparation method provided in the second aspect of the present disclosure, the coating can be formed into a reticular trabecular bone structure. Based on its rough and porous surface structure, it can well induce the generation of heterotopic bone and can improve the adhesion, proliferation and differentiation abilities of osteoblasts. Research data show that the internal fixation micro-motion range less than 28 μm can meet the requirements of biological fixation of bone ingrowth. When the micro-motion is greater than 150 μm, a soft tissue membrane will be generated at the prosthesis-bone interface, affecting the fixation effect. The surface roughness at the macroscopic scale can greatly reduce the micro-motion and is conducive to bone ingrowth. At the same time, melting and cladding the titanium-based alloy powder on the surface of the substrate can enable the formed coating to be tightly combined with the substrate, thereby ensuring the coating strength. At the same time, the formed double-component ceramic surface hip prosthesis has a stable and reliable structure and high fatigue strength, effectively ensuring the service life of the double-component ceramic surface hip prosthesis.

[0113] The preferred embodiments of the present disclosure have been described in detail above in conjunction with the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

Claims

1. A two-component ceramic surface hip prosthesis, characterized in that: It comprises an acetabular outer cup and a surface ball head made of ceramic material, wherein a femoral stem is arranged in an inner cavity of the surface ball head; the surface ball head is embedded in the acetabular outer cup and can rotate relative to the acetabular outer cup, wherein the outer wall surface of the acetabular outer cup and the inner wall surface of the surface ball head are both clad with a trabecular bone layer, and the trabecular bone layer is in a mesh shape.

2. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The porosity of the trabecular layer is 50-90%, and the pore size is 100-400 μm.

3. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The thickness of the trabecular bone layer is 1.4 to 1.6 mm.

4. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The trabecular bone layer is provided on the outer wall surface and the inner wall surface of the surface ball head.

5. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The outer surface of the acetabulum outer cup is provided with mesh-shaped reinforcing ribs.

6. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The inner wall surface of the surface ball head is provided with a strip-shaped limiting groove, and the limiting groove extends along the vertex of the surface ball head; / and, the limiting grooves are provided in plurality and are evenly spaced along the circumferential direction of the femoral head; / and, the groove wall of the limiting groove is a curved surface.

7. The dual-component ceramic surface hip prosthesis according to claim 1, characterized in that: The ceramic material includes α-alumina powder and zirconium oxide powder.

8. The dual-component ceramic surface hip prosthesis according to claim 7, characterized in that: The purity of the α-alumina powder is ≥99.9%, and the particle size of the α-alumina powder is from submicron to nanometer level.

9. The dual-component ceramic surface hip prosthesis according to claim 7, characterized in that: The zirconium oxide powder comprises yttrium oxide and tetragonal zirconium oxide powder, and the yttrium oxide accounts for 3% of the mass of the zirconium oxide.

10. The dual-component ceramic surface hip prosthesis according to claim 7, characterized in that: The ceramic material also includes strontium oxide and / or chromium oxide.

Images