Three-component hip joint prosthesis with laser cladding coating on surface

Abstract

The invention relates to a three-component hip joint prosthesis with a laser cladding coating on the surface. The three-component hip joint prosthesis with the surface laser cladding coating comprises an acetabulum outer cup, an acetabulum inner cup and a surface ball head made of a ceramic material, the acetabulum inner cup is embedded in a cup cavity of the acetabulum outer cup, and the acetabulum inner cup is connected to the acetabulum outer cup in a lockable mode; the surface ball head is embedded in the acetabulum inner cup and can rotate relative to the acetabulum inner cup, a femoral stem is arranged in an inner cavity of the surface ball head, and bone trabecula layers are cladded on the outer wall surface of the acetabulum outer cup and the inner wall surface of the surface ball head. Therefore, the problems that in the prior art, metal chippings are generated on the 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 are solved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of artificial joints, and specifically, to a three-component hip joint prosthesis with a surface laser cladding coating. Background Art

[0002] As a surgical implant for replacing the diseased part of the human hip joint, the surface hip joint prosthesis is designed to provide an effective solution that can both restore function and reduce complications. Traditional surface hip joint prostheses mainly consist of a surface acetabular outer cup prosthesis and a femoral head prosthesis sleeved on the human femoral head. Compared with traditional total hip replacement, such prostheses can effectively reduce postoperative complications and revision rates, and reserve 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 joint 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 surrounding tissues of the prosthesis due to the presence of metal debris.

[0006] 2. Risk of outer cup deformation: In order to preserve 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 the existing surface hip joint prostheses have solved 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 of the friction interface of the surface hip joint prosthesis in the prior art, such as the generation of metal debris easily leading to prosthesis loosening, the outer cup being easily deformed, and the poor effect of the outer cup inducing osteocyte ingrowth. Summary of the Invention

[0009] The purpose of the present disclosure is to provide a three-component hip joint prosthesis with a surface laser cladding coating, which can solve the problems of the friction interface of the surface hip joint prosthesis in the prior art, such as the generation of metal debris easily leading to prosthesis loosening, the outer cup being easily deformed, and the poor effect of the outer cup inducing osteocyte ingrowth.

[0010] To achieve the above purpose, the present disclosure provides a three-component hip joint prosthesis with a surface laser cladding coating, including an outer acetabular cup, an inner acetabular cup, and a surface ball head made of ceramic material. The inner acetabular cup is embedded in the cup cavity of the outer acetabular cup, and the inner acetabular cup is lockably connected to the outer acetabular cup; the surface ball head is embedded in the inner acetabular cup and can rotate relative to the inner acetabular cup. A femoral stem is provided in the inner cavity of the surface ball head. Among them, a trabecular bone layer is cladded on the outer wall surface of the outer acetabular cup and the inner wall surface of the surface ball head.

[0011] In a possible design, the porosity of the trabecular bone layer is 50-90%, the pore diameter is 100-400 μm, and the thickness of the trabecular bone layer is 1.4-1.6 mm.

[0012] 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;

[0013] The outer surface of the outer acetabular cup is provided with a net-shaped reinforcing rib.

[0014] In a possible design, the outer acetabular cup is provided with a central hole, and nail holes are provided around the central hole. The nail holes are provided in multiple numbers and are spaced relative to the central hole.

[0015] In a possible design, 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;

[0016] / and, the limiting grooves are provided in multiple numbers and are evenly spaced along the circumferential direction of the femoral head;

[0017] / and, the groove wall of the limiting groove is an arc surface.

[0018] In a possible design, a clamping platform is provided on the inner wall of the acetabular outer cup, and a clamping groove adapted to the clamping platform is provided on the outer wall of the acetabular inner cup, so that the clamping platform can be embedded in the clamping groove;

[0019] / And, a guiding groove corresponding to the clamping groove is further provided on the acetabular inner cup, and the groove wall of the guiding groove is an arc surface with a gradually changing radian to guide the clamping platform to move along the guiding groove.

[0020] In a possible design, a positioning groove is provided on the inner wall of the acetabular outer cup, and a positioning platform adapted to the positioning groove is provided on the outer wall of the acetabular inner cup; when the acetabular inner cup is embedded in the acetabular outer cup, the positioning platform is embedded in the positioning groove;

[0021] The outer wall surface of the positioning platform is formed into a curved surface.

[0022] In a possible design, the ceramic material includes α-aluminum oxide powder and zirconia powder.

[0023] 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; the zirconia powder includes yttrium oxide and tetragonal zirconia powder, and yttrium oxide accounts for 3% of the mass of zirconia.

[0024] In a possible design, the ceramic material further includes strontium oxide and / or chromium oxide.

[0025] This double-layer structure design of the acetabular outer cup and the acetabular inner cup enables the acetabular inner cup to be firmly locked in the acetabular outer cup, while allowing the acetabular inner cup to be finely adjusted relative to the acetabular outer cup to adapt to different anatomical structures and individual needs. The surface ball head is embedded in the acetabular inner cup and can rotate freely, mimicking the ball-and-socket movement mechanism of the human hip joint. A femoral stem is provided in the inner cavity of the surface ball head to ensure good connection and stability with the thigh bone (femur). Through the surface laser cladding technology, a reticular trabecular bone layer is formed on the outer wall surface of the acetabular outer cup and the inner wall surface of the surface ball head. These trabecular bone layers not only increase the contact area between the prosthesis and the surrounding bone tissue, promote the growth of new bone into these micropores, thereby enhancing the fixation effect of the prosthesis; but also they mimic the internal microstructure of natural bone, helping to reduce the stress shielding phenomenon and promoting better long-term biological integration.

[0026] Through the above technical solution, the presence of the trabecular layer greatly improves the mechanical locking ability between the prosthesis and the host bone, promotes bone ingrowth, and achieves good long-term stability. The acetabular outer cup and the surface ball head made of high-quality ceramic materials have extremely high hardness and low friction coefficients, reduce the generation of wear particles, and extend the service life of the prosthesis. The trabecular layer with bionic design is close to the structure of natural human bones, which is conducive to cell attachment and the formation of new blood vessels, further enhancing the biocompatibility and integration effect of the prosthesis. This design takes into account the issue of stress distribution, helps to disperse the load, reduces local stress concentration, and prevents the occurrence of complications such as loosening and sinking.

[0027] Other features and advantages of the present disclosure will be described in detail in the following detailed implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the following detailed implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0029] Figure 1 is a three-component hip joint prosthesis with a surface laser cladding coating, showing a three-dimensional structural schematic view from one perspective, where the trabeculae are not shown;

[0030] Figure 2 is a three-component hip joint prosthesis with a surface laser cladding coating, showing a three-dimensional structural schematic view from another perspective, where the trabeculae are not shown;

[0031] Figure 3 is the tensile strength test chart of part A1 in Example 1;

[0032] Figure 4 is the tensile strength test chart of part A2 in Example 1;

[0033] Figure 5 is the tensile strength test chart of part A3 in Example 1;

[0034] Figure 6 is the tensile strength test chart of part A4 in Example 1;

[0035] Figure 7 is the cross-sectional view of parts A1 and A2 in Example 1 after the tensile test. Among them, the part in the upper group is A1, and the part in the lower group is A2;

[0036] Figure 8 is the cross-sectional view of parts A3 and A4 in Example 1 after the tensile test. Among them, the part in the upper group is A3, and the part in the lower group is A4;

[0037] Figure 9 It is a schematic structural diagram of trabecular bone, where Lt refers to the cladding path spacing (i.e., the groove width of the trabecular bone along the circumferential direction);

[0038] Figure 10 It is a schematic structural diagram of trabecular bone, where Lc refers to the cladding layer spacing (i.e., the spacing of the trabecular bone of adjacent layers in the diameter direction);

[0039] Figure 11 It is a schematic structural diagram of a three-component hip joint prosthesis with a surface laser cladding coating. Among them, the coating cladded on the outer acetabular cup is the trabecular bone.

[0040] Explanation of reference numerals

[0041] 1 - Outer acetabular cup, 11 - Nail hole, 12 - Central hole, 13 - Chuck, 14 - Positioning groove, 2 - Inner acetabular cup, 21 - Card slot, 22 - Guide groove, 23 - Positioning table, 3 - Surface ball head, 4 - Femoral stem, 5 - Trabecular bone layer, 6 - Reinforcing rib, 7 - Limiting groove, 8 - Groove. Specific embodiments

[0042] The following will describe the specific embodiments of the present disclosure in detail with reference to the accompanying drawings.

[0043] According to the first aspect of the present disclosure, there is provided a three-component hip joint prosthesis with a surface laser cladding coating, where Figures 1 to 11 One specific embodiment is shown.

[0044] The three-component hip joint prosthesis with a surface laser cladding coating includes an outer acetabular cup 1, an inner acetabular cup 2, and a surface ball head 3 made of ceramic material. The inner acetabular cup 2 is embedded in the cup cavity of the outer acetabular cup 1, and the inner acetabular cup 2 is lockably connected to the outer acetabular cup 1; the surface ball head 3 is embedded in the inner acetabular cup 2 and can rotate relative to the inner acetabular cup 2. A femoral stem 4 is provided in the inner cavity of the surface ball head 3. Among them, the outer wall surface of the outer acetabular cup 1 and the inner wall surface of the surface ball head 3 are both cladded with a trabecular bone layer 5.

[0045] The double-layer structure design of the acetabular outer cup 1 and the acetabular inner cup 2 enables the acetabular inner cup 2 to be firmly locked in the acetabular outer cup 1, while allowing the acetabular inner cup 2 to be finely adjusted relative to the acetabular outer cup 1 to adapt to different anatomical structures and individual needs. The surface ball head 3 is embedded in the acetabular inner cup 2 and can rotate freely, mimicking the ball-and-socket movement mechanism of the human hip joint. A femoral stem 4 is provided in the inner cavity of the surface ball head 3 to ensure good connection and stability with the thigh bone (femur). Through the surface laser cladding technology, a reticular trabecular layer 5 is formed on the outer wall surface of the acetabular outer cup 1 and the inner wall surface of the surface ball head 3. These trabecular layers 5 not only increase the contact area between the prosthesis and the surrounding bone tissue, promote the growth of new bone into these micropores, thereby enhancing the fixation effect of the prosthesis; but also they mimic the microstructure inside natural bone, helping to reduce the stress shielding phenomenon and promoting better long-term biological integration.

[0046] The application process of the three-component hip prosthesis with the surface laser cladding coating is as follows: According to the patient's imaging data (such as X-ray films or CT scans), determine the size and position of the hip prosthesis and formulate a personalized surgical plan. Make an appropriate incision at the root of the patient's thigh to expose the hip joint area. Remove the damaged acetabulum and femoral head parts. First, accurately place the acetabular outer cup 1 at the acetabulum, then insert the acetabular inner cup 2 into the acetabular outer cup 1 and ensure its firm connection through the locking mechanism. Insert the femoral stem 4 into the femoral medullary cavity and ensure its firm fixation. Then, install the surface ball head 3 onto the femoral stem 4 and make it embedded in the acetabular component. Test the range of motion of the hip joint to ensure that there is no dislocation or other abnormalities. After confirming that all components are correct, suture the muscles, fascia, and skin layer by layer. Close the incision, check the joint range of motion, and confirm whether the prosthesis is correctly installed and functioning properly.

[0047] Through the above technical solution, the presence of the trabecular layer 5 greatly improves the mechanical locking ability between the prosthesis and the host bone, promotes bone ingrowth, and achieves good long-term stability. The acetabular outer cup 1 and the surface ball head 3 made of high-quality ceramic materials have extremely high hardness and low friction coefficients, reducing the generation of wear particles and extending the service life of the prosthesis. The bionic design of the trabecular layer 5 is close to the structure of the human natural bone, which is beneficial to cell attachment and the formation of new blood vessels, further enhancing the biocompatibility and integration effect of the prosthesis. This design takes into account the problem of stress distribution, helps to disperse the load, reduce local stress concentration, and prevent the occurrence of complications such as loosening and subsidence.

[0048] In the present disclosure, since the trabecular layer 5 is prepared by the coating preparation method of the second aspect, the three-component hip joint prosthesis with a surface laser cladding coating thus made 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 three-component hip joint prosthesis with a surface laser cladding coating has been subjected to a cladding treatment when implanted, due to the presence of the provided reticular trabeculae, 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. Meanwhile, 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, fretting can be greatly reduced, which is beneficial to bone ingrowth.

[0049] In a possible design, the porosity of the trabecular layer 5 is 50-90%, which is beneficial to promoting bone tissue ingrowth. The trabecular layer 5 can provide sufficient space for the migration, proliferation and differentiation of bone cells, thereby promoting the growth of new bone tissue. The pore diameter 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.

[0050] By setting appropriate pore diameters 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.

[0051] In a possible design, the thickness of the trabecular layer 5 is 1.4-1.6 mm. The appropriate thickness helps to maintain the structural strength of the implant and ensure that it can withstand the mechanical loads in daily activities. In this way, the bone tissue can be stably combined with the trabecular layer 5, improving the compressive strength and fatigue life of the implant, thereby reducing possible problems during long-term use.

[0052] In the present disclosure, the thickness of the trabecular layer 5 is 1.5 mm, which can balance biocompatibility and mechanical properties and meet the requirements of clinical applications at the same time.

[0053] In a possible design, the outer wall surface and the inner wall surface of the surface ball head 3 are both provided with a trabecular bone layer 5. The trabecular bone layer 5 provided on the inner wall surface can provide better fixation support for the femoral head or other internal components, which is conducive to promoting the direct bonding between the prosthesis and the host bone. In this way, a surface closer to the natural bone environment can be provided, which can increase the biocompatibility between the prosthesis and the surrounding bone tissue and reduce the risk of foreign body reaction. By simultaneously providing the trabecular bone layer 5 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.

[0054] In a possible design, the outer surface of the acetabular outer cup 1 is provided with a reticular reinforcing rib 6. This can enhance the overall structural stability of the acetabular outer cup 1, effectively disperse the load 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 6, the surface area of contact between the acetabular outer 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 6 can also produce an effect similar to the trabecular bone 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.

[0055] It should be noted that for the term “and / or” appearing in this article, it is merely a description of the association relationship of associated objects, indicating that three relationships can exist. 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 of associated objects, indicating that two relationships can exist. For example, A / and B can represent: A exists alone, and both A and B exist. Additionally, for the character “ / ” that may appear in this article, generally it represents an “or” relationship between the front and rear associated objects.

[0056] In the present disclosure, the femoral stem 4 is provided with a plurality of grooves 8 arranged along its circumferential direction. The grooves 8 can guide bone tissue to combine with the femoral stem 4 from different positions, and can prevent the surface ball head 3 from rotating unnecessarily relative to the femur to a certain extent, which is conducive to maintaining the long-term stability of the prosthesis.

[0057] The acetabular outer cup 1 is provided with a central hole 12, and nail holes 11 are provided around the central hole 12. The nail holes 11 are provided in multiple numbers and are spaced relative to the central hole 12. The presence of the central hole 12 and the nail holes 11 allows the use of bone nails (such as titanium nails) to firmly fix the acetabular outer cup 1 to the acetabular bone mass of the patient. This mechanical fixation method increases the direct connection points between the prosthesis and the host bone, helps to disperse the load, and reduces the risk of prosthesis loosening caused by osteoporosis.

[0058] By using multiple pin holes 11 to install bone pins, additional support can be provided in different directions and positions, which not only enhances the initial stability of the prosthesis but also lays the foundation for long-term biologic integration. For patients with poor bone quality, traditional prosthesis fixation methods may not be sufficient to provide adequate support. However, this design with a central hole 12 and pin holes 11 can provide additional fixation force through bone pins, making the prosthesis more suitable for patients with osteoporosis.

[0059] In a possible design, the inner wall surface of the surface ball head 3 is provided with a strip-shaped limiting groove 7 that extends along the vertex of the surface ball head 3. Such a setting allows bone tissue to combine with the surface ball head 3 from different positions, effectively preventing the surface ball head 3 from rotating, thereby maintaining the long-term stability of the prosthesis, especially under repeated stress. The limiting groove 7 increases the contact area and friction between the internal components and the surface ball head 3, thus enhancing the stability of the overall structure.

[0060] In the present disclosure, a plurality of limiting grooves 7 are provided and 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 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 7 can serve as a fixed reference point to ensure the correct position of the femoral head within 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. Evenly spacing the limiting grooves 7 in the circumferential direction can help better simulate the behavior of natural joints, enabling the prosthesis to respond more naturally to various forces during daily activities.

[0061] In the present disclosure, the groove wall of the limiting groove 7 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 3, 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.

[0062] In a preferred embodiment, the inner wall of the acetabular outer cup 1 is provided with a clamping platform 13, and the outer wall of the acetabular inner cup 2 is provided with a clamping groove 21 adapted to the clamping platform 13, so that the clamping platform 13 can be embedded in the clamping groove 21. When the acetabular inner cup 2 is inserted into the acetabular outer cup 1, the clamping groove 21 thereon will slide along the clamping platform 13 inside the acetabular outer cup 1 until the two are completely engaged. This interlocking structure not only increases the friction between the two components but also prevents relative movement between them.

[0063] The design of the clamping platform 13 and the clamping groove 21 ensures the precise positioning of the acetabular inner cup 2 within the acetabular outer cup 1, avoiding functional problems or discomfort caused by positional deviations. This mechanical locking mechanism greatly enhances the connection strength between the acetabular inner cup 2 and the acetabular outer cup 1, reducing the risk of prosthesis loosening, especially when bearing large loads. This mating structure can simplify the surgical procedure, reduce adjustment time, and improve surgical efficiency.

[0064] Furthermore, the acetabular inner cup 2 is also provided with a guiding groove 22 corresponding to the clamping groove 21. The groove wall of the guiding groove 22 is an arc surface with a gradually changing curvature to guide the clamping platform 13 to move along the guiding groove 22. When the acetabular inner cup 2 is pushed into the acetabular outer cup 1, the clamping platform 13 first contacts the entrance of the guiding groove 22. As the acetabular inner cup 2 continues to be pushed in, the clamping platform 13 moves along the arc surface of the guiding groove 22 until it finally engages in the clamping groove 21 to complete the locking.

[0065] The design of the guiding groove 22 enables the acetabular inner cup 2 to be inserted into the acetabular outer cup 1 more smoothly and ensures that the clamping platform 13 accurately enters the clamping groove 21. Through the guiding groove 22 with a specific curvature change, precise positioning between the inner and outer acetabular cups can be achieved, avoiding problems caused by inaccurate manual alignment. Additionally, the groove wall with a gradually changing curvature can provide a smooth transition during the insertion process, reducing any possible resistance or jamming phenomena, thereby protecting the prosthesis material from damage. Moreover, the arc design of the guiding groove 22 helps to automatically correct minor positional deviations. Even if the initial alignment is not completely precise, the correct installation position can be achieved through the guiding effect of the guiding groove 22.

[0066] In a possible design, the inner wall of the acetabular outer cup 1 is provided with a positioning groove 14, and the outer wall of the acetabular inner cup 2 is provided with a positioning platform 23 adapted to the positioning groove 14; when the acetabular inner cup 2 is embedded in the acetabular outer cup 1, the positioning platform 23 is embedded in the positioning groove 14.

[0067] By providing the positioning groove 14 on the inner wall of the acetabular outer cup 1 and the corresponding positioning platform 23 on the outer wall of the acetabular inner cup 2, precise alignment between the two components is achieved. The tight fit between the positioning groove 14 and the positioning platform 23 can effectively prevent the acetabular inner cup 2 from rotating or shifting relative to the acetabular outer cup 1, which has an important role and significance in maintaining the long-term stability and function of the prosthesis.

[0068] Furthermore, the outer wall surface of the positioning table 23 is formed as a curved surface, which helps to provide a smoother transition during the insertion process and can better adapt to the shape of the positioning groove 14 on the inner wall of the acetabular outer cup 1. Additionally, the characteristics of the curved surface allow the positioning table 23 to have a certain self-adjusting ability during the process of entering the positioning groove 14. Even if the initial alignment is not completely precise, the final accurate fitting can be achieved through slight angular or positional adjustments.

[0069] 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 high corrosion resistance, which allows the prosthesis made from it to be used for a long time in a harsh environment.

[0070] Zirconia (ZrO2) is a very hard and tough ceramic material with the characteristics of 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 the zirconia undergoes a transformation toughening mechanism under stress, that is, energy is absorbed during the process of t-ZrO2 transforming into m-ZrO2, thereby preventing crack propagation. In addition, zirconia also has good thermal shock resistance and can withstand a large temperature difference during rapid heating and cooling without cracking.

[0071] In the present disclosure, α-aluminum oxide and zirconia are used in combination. 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, and improving the toughness and strength of the ceramic material. This not only improves the wear resistance of the prosthesis but also enhances its mechanical strength and toughness, making it more suitable for the treatment needs of young and active patients.

[0072] In a possible design, the purity of the α-aluminum oxide 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-aluminum oxide powder is in the sub-micron to nano range. The α-aluminum oxide powder with a sub-micron to nano 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 3.

[0073] 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 precipitating agent, 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 gel with a three-dimensional network structure, and then nano-scale oxide powders are obtained through drying and calcination.

[0074] 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 enabling the structure and properties to remain stable in a high-temperature environment.

[0075] In a possible design, the ceramic material further includes strontium oxide. The addition of strontium oxide helps to form a liquid phase, can reduce the sintering temperature and accelerate the rearrangement and densification process between particles, thereby changing the diffusion mechanism during sintering, promoting more uniform grain growth, and thus improving the density and mechanical strength of the final product. In this way, the acetabular outer cup 1 and the surface ball head 3 prepared therefrom can have good 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.

[0076] 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.

[0077] 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 through 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.

[0078] 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. 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, to a certain extent, replace pure alumina and better control the microstructure of the ceramic material, such as refining grains and reducing porosity, and improving material density and mechanical properties.

[0079] According to the second aspect of the present disclosure, a coating preparation method for a three-component hip joint prosthesis with a surface laser cladding coating is provided. This coating preparation method is used for a three-component hip joint prosthesis with a surface laser cladding coating, and the trabecular layer 5 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: pre-treating 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; and 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 for the ingrowth of the host bone after the prosthesis implantation, thereby improving the stability of the prosthesis.

[0080] 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 rate, 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.

[0081] 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 rate is 6 g / min - 12 g / min; and the protective gas pressure value is 1.8 - 2.2 bar.

[0082] 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 rate is 8 g / min; and the protective gas pressure value is 2 bar.

[0083] 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.

[0084] 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, increases in size by 2 mm, and stops coating at the 70-mm ring diameter; the coating on the surface ball head 3 starts to be coated from the 35-mm ring diameter of the surface ball head 3, increases in size by 2 mm, and stops coating at the 65-mm ring diameter.

[0085] 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 as at least one layer. It can be understood that the coating is formed into the trabecular layer 5 described below. The application of this preparation method to a three-component hip joint prosthesis with a surface laser-cladded coating will be described in detail below as an example. Among them, the maximum diameter of the substrate (the three-component hip joint prosthesis with a surface laser-cladded coating without a coating) is 72 mm.

[0086] 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 a 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 one without a cladded coating. After the two parts are fixedly bonded together to obtain a test combined part, then the two 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.

[0087] Example 1:

[0088] 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; the number of cladding layers is 4 layers, and the cladding layer width is 0.2 mm.

[0089] The titanium-based alloy powder is configured as a titanium-6-aluminum-4-vanadium alloy powder; 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 a titanium-6-aluminum-4-vanadium alloy powder.

[0090] Example 2:

[0091] 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 0.3 mm; the cladding path spacing is 0.6 mm; the cladding layer spacing is 0.2 mm; the number of cladding layers is 3, and the cladding layer width is 0.3 mm.

[0092] 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.

[0093] Example 3:

[0094] 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.

[0095] 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.

[0096] Example 3:

[0097] 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.

[0098] 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.

[0099] Example 4:

[0100] 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.

[0101] 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.

[0102] Select a clad part from Example 1, and then bond it with an unclad part to obtain a combined part marked as A1 (see Figure 3 ). Select a clad part from Example 2, and then bond it with an unclad part to obtain a combined part marked as A2 (see Figure 4 ); select a clad part from Example 3, and then bond it with an unclad part to obtain a combined part marked as A3 (see Figure 5 ), select a clad part from Example 4, and then bond it with an unclad part to obtain a combined part marked as A4 (see Figure 6 ). It should be noted that according to the standard YY 0118-2016 "Hip Joint Prosthesis for Joint Replacement Implants", the tensile strength requirement of the part is greater than 22 MPa.

[0103] Conduct laser clad coating mechanical tensile strength tests on the combined parts A1, A2, A3, and A4 respectively, and obtain the following data.

[0104]

[0105]

[0106] Table 1 - Test Results Table of Part Tensile Strength

[0107] Referring to Table 1 and Figures 3 to 6 it can be seen that in the combined parts A1 (see Figure 7 ), A2 (see Figure 7 ), A3 (see Figure 8 ), and A4 (see Figure 8 ), the fracture cross-sections are all located in the clad layer, that is, the fusion bonding surface between the two parts, rather than the fracture between the clad layer and the part. The above tests can all prove that: the bonding strength between the coating (trabecular 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 prone to debris and other situations. After conducting clad coating mechanical tensile strength tests on 4 groups of clad parts respectively, the mechanical strength of the clad parts is much higher than the industry standard value, and the test results all meet the standard ASTM F1147. The coating quality of the clad products is qualified, and the stability is above 97%.

[0108] In summary, through the coating preparation method provided in the second aspect of the present disclosure, the coating can be formed into a reticular trabecular structure. Based on its rough and porous surface structure, it can well induce the generation of heterotopic bone and improve the adhesion, proliferation, and differentiation abilities of osteoblasts. Research data shows that an internal fixation micromotion range less than 28 μm can meet the requirements for biological fixation of bone ingrowth, while when the micromotion 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 micromotion and is conducive to bone ingrowth. At the same time, 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 three-component hip joint prosthesis with the formed surface laser cladding coating has a stable and reliable structure and high fatigue strength, effectively ensuring the service life of the three-component hip joint prosthesis with the surface laser cladding coating.

[0109] 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 three-component hip prosthesis with a surface laser cladding coating, characterized in that: It includes an acetabular outer cup, an acetabular inner cup and a surface ball head made of ceramic material, wherein the acetabular inner cup is embedded in the cup cavity of the acetabular outer cup and the acetabular inner cup can be lockedly connected to the acetabular outer cup; the surface ball head is embedded in the acetabular inner cup and can rotate relative to the acetabular inner cup, a femoral stem is arranged in the inner cavity of the surface ball head, 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.

2. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1 is characterized in that: The porosity of the trabecular bone layer is 50-90%, the pore size is 100-400 μm, and the thickness of the trabecular bone layer is 1.4-1.6 mm.

3. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1 is characterized in that: The outer wall surface and the inner wall surface of the surface ball head are both provided with the trabecular bone layer; The outer surface of the acetabulum outer cup is provided with mesh-shaped reinforcing ribs.

4. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1 is characterized in that: The acetabular outer cup is provided with a central hole, and nail holes are provided around the central hole. The nail holes are arranged in plurality and are spaced relative to the central hole.

5. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1 is 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.

6. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1 is characterized in that: The inner wall of the acetabulum outer cup is provided with a clamping platform, and the outer wall of the acetabulum inner cup is provided with a clamping groove matched with the clamping platform, so that the clamping platform can be embedded in the clamping groove; / and, the acetabular inner cup is also provided with a guide groove corresponding to the clamping groove, and the groove wall of the guide groove is an arc surface with a gradually changing curvature to guide the clamping platform to move along the guide groove.

7. The three-component hip joint prosthesis with a surface laser cladding coating according to claim 6, characterized in that: The inner wall of the acetabular outer cup is provided with a positioning groove, and the outer wall of the acetabular inner cup is provided with a positioning platform matched with the positioning groove; when the acetabular inner cup is embedded in the acetabular outer cup, the positioning platform is embedded in the positioning groove; The outer wall surface of the positioning table is formed into a curved surface.

8. The three-component hip joint prosthesis with surface laser cladding coating according to claim 1, characterized in that: The ceramic material includes α-alumina powder and zirconium oxide powder.

9. The three-component hip joint prosthesis with surface laser cladding coating according to claim 8, 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; the zirconium oxide powder includes yttrium oxide and tetragonal zirconium oxide powder, and the yttrium oxide accounts for 3% of the mass of the zirconium oxide.

10. The three-component hip joint prosthesis with surface laser cladding coating according to claim 8, characterized in that: The ceramic material also includes strontium oxide and / or chromium oxide.

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