Degradable zinc alloy reinforced polymer acetabular cup and processing method thereof

Abstract

The invention provides a degradable zinc alloy reinforced macromolecule acetabular cup and a processing method thereof.The acetabular cup is provided with a multi-filling-hole metal acetabular cup framework, the multi-filling-hole metal acetabular cup framework is formed by interweaving silk threads, filling holes are formed among the silk threads, the silk threads are made of degradable metal materials, the filling holes are filled with macromolecule materials, and the degradable zinc alloy reinforced macromolecule acetabular cup is made of degradable zinc alloy. The outer portion of the multi-filling-hole metal acetabular cup framework is coated with a layer of high polymer materials, a first locking hole and a second locking hole are formed in the multi-filling-hole metal acetabular cup framework, and the first locking hole and the second locking hole penetrate through the high polymer materials which are coated on the outer portion of the multi-filling-hole metal acetabular cup framework. The degradable metal material is corroded and degraded by body fluid in the body, and the left high polymer material structure reserves a space for the ingrowth of bone tissues. The acetabular cup is made of degradable metal materials which do not need to be used in cooperation with bone cement, and surrounding tissue and nerves cannot be damaged. The acetabular cup can be widely applied to medical acetabular cups.

Description

[0001] This application is a divisional application of the patent application filed on June 24, 2024, with application number 2024108132924 and invention title "High-strength Acetabular Cup with Osteoinductive Properties". Technical Field

[0002] This invention relates to an acetabular cup, and more particularly to a biodegradable zinc alloy reinforced polymer acetabular cup and its processing method. Background Technology

[0004] A medical acetabular cup is a medical device used in hip replacement surgery. It is usually made of medical-grade metal materials, such as stainless steel and titanium alloy, which have certain strength and corrosion resistance and are widely used.

[0005] However, because the acetabular cup is a solid structure, it has problems such as large weight and mismatch between its elastic modulus and human bone, which makes it easy for the acetabular cup to fall out and shift after implantation.

[0006] For the problem of acetabular cup dislocation and displacement, two methods are usually used: bone cement fixation or biological fixation. However, bone cement is an inert material that can only form a mechanical bond between the bone and the acetabular cup, which inevitably leads to problems such as aging, breakage and wear of the acetabular cup. In addition, bone cement monomers release heat when polymerizing, which can damage surrounding tissues and nerves.

[0007] Biological fixation promotes bone ingrowth by sandblasting, coating, or sintering metal microbeads on the outer surface of the acetabular cup. Although such biological prostheses have good osseointegration capabilities, the sandblasting process has a low coefficient of friction, and the connection between the coating and the substrate is prone to cracking under load. In the long term, the prosthesis will inevitably shed coating debris, which will lead to loosening of the prosthesis. Summary of the Invention

[0009] To address the above-mentioned technical problems, this invention provides a biodegradable zinc alloy reinforced polymer acetabular cup and its processing method. In this processing method, the acetabular cup is made of a biodegradable metal material. This material does not require use with bone cement and will not damage surrounding tissues and nerves. It avoids the problems of aging, cracking, and wear that can occur with bone cement fixation. Furthermore, the biodegradable metal material is gradually corroded and degraded by body fluids in the body to form a bio-type acetabular cup. The released metal plasma can induce bone tissue growth, and the remaining porous polyetheretherketone or ultra-high molecular weight polyethylene structure provides suitable space for bone tissue ingrowth, promoting bone tissue ingrowth and ensuring the long-term stable use of the acetabular cup.

[0010] Therefore, the technical solution of the present invention is a processing method for a biodegradable zinc alloy reinforced polymer acetabular cup, comprising preparing a reinforcing material and a matrix material, wherein the reinforcing material is a biodegradable zinc alloy wire and the matrix material is ultra-high molecular weight polyethylene powder, and the processing method includes the following steps: Step (1): The biodegradable zinc alloy wire is used to prepare a multi-pore zinc alloy acetabular cup skeleton, and the processing method is wire weaving; The diameter of the biodegradable zinc alloy wire is 490μm-620μm, and the particle size of the ultra-high molecular weight polyethylene powder is 60μm-82μm. The pore size of the multi-porosity zinc alloy acetabular cup skeleton is 71μm-86μm, and the porosity is 61%-75%. Step (2): Place the prepared multi-filled porous zinc alloy acetabular cup skeleton into the cavity mold, and then fill the cavity mold with ultra-high molecular weight polyethylene powder. The filling method is to fill in the same amount multiple times, and the number of times the equal amount filling is five. After each filling, the ultra-high molecular weight polyethylene powder is evenly filled into the filling pores of the multi-filled porous zinc alloy acetabular cup skeleton by vibration. The vibration method is mechanical vibration or ultrasonic vibration, and the vibration time is 22min-34min. After uniform filling, the mixed material is pressurized and formed by the cavity mold. The pressing method is vacuum hot isostatic pressing or vacuum cold isostatic pressing. The pressure is 110MPa-175MPa, and the holding time is 22min-35min. After pressing and forming, the acetabular cup semi-finished product is obtained. Step (3): The semi-finished acetabular cup is placed in a high-temperature oven for sintering. The sintering method is hot pressing sintering, vacuum hot isostatic pressing sintering, gas pressure sintering, microwave sintering, spark plasma sintering or solid metal sintering. The sintering temperature is 305℃-365℃ and the sintering time is 0.6h-1.2h. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

[0011] Preferably, in step (1), the biodegradable zinc alloy wire has a diameter of 550 μm, the polyetheretherketone powder has a particle size of 75 μm, and the multi-pore zinc alloy acetabular cup skeleton has a pore size of 80 μm and a porosity of 70%. The oscillation method in step (2) is ultrasonic oscillation, and the oscillation time is 30 minutes; The pressure molding method in step (2) is vacuum hot isostatic pressing, with a pressure of 150 MPa and a holding time of 30 min; The sintering method in step (3) is vacuum hot isostatic pressing sintering, the sintering temperature is 340℃, and the sintering time is 1h.

[0012] A biodegradable zinc alloy reinforced polymer acetabular cup processed using the above processing method has a multi-filled porous metal acetabular cup skeleton. The multi-filled porous metal acetabular cup skeleton is formed by interwoven wires, and the interwoven wires form filling pores. The wires are biodegradable metal materials. The pores are filled with polymer material, and the outside of the multi-pore metal acetabular cup skeleton is covered with a layer of polymer material. The top of the multi-porosity metal acetabular cup skeleton is provided with a first locking hole, and the middle position of the multi-porosity metal acetabular cup skeleton is provided with a second locking hole. The first locking hole and the second locking hole pass through the polymer material covering the outside of the multi-porosity metal acetabular cup skeleton. A positioning boss is provided on the outer circumference of the first locking hole, and the positioning boss protrudes outward along the top of the multi-filled pore metal acetabular cup skeleton; The bottom end of the multi-filled porous metal acetabular cup skeleton is provided with a downward-opening acetabular liner fixing groove, and the adjacent inner surface of the bottom end of the multi-filled porous metal acetabular cup skeleton is provided with an acetabular liner fixing boss. Biodegradable metallic materials are corroded and degraded by body fluids in the body, leaving behind a polymer structure that creates space for bone tissue ingrowth. The polymer material is a mixture of biodegradable zinc alloy wire and ultra-high molecular weight polyethylene powder.

[0013] Preferably, a support ring is provided at the lower end of the multi-filled porous metal acetabular cup skeleton located at the upper end of the acetabular liner fixing groove, and the support ring protrudes outward from the multi-filled porous metal acetabular cup skeleton.

[0014] Preferably, a biodegradable metal mesh is fixed to the outside of the acetabular cup. The biodegradable metal mesh has a porous mesh structure and is formed by interwoven wires. The external structure of the acetabular cup and the biodegradable wire mesh are secured by snap-fit ​​or screw-locking. The biodegradable metal wire mesh has a third locking hole at the top and a fourth locking hole in the middle. The positions of the third and fourth locking holes are symmetrical to the positions of the first and second locking holes, respectively. A positioning boss is provided on the outer circumference of the third locking hole, and the positioning boss protrudes outward along the top of the biodegradable metal wire mesh.

[0015] Preferably, the number of acetabular liner fixing grooves is four, and the four acetabular liner fixing grooves are evenly arranged along the bottom circumferential direction of the multi-filled pore metal acetabular cup skeleton. There are four acetabular liner fixing bosses, which are evenly distributed in the middle of two adjacent acetabular liner fixing grooves.

[0016] Preferably, the outer surface of the acetabular cup is smoothly transitioned by rounded corners.

[0017] The beneficial effects of this invention are: 1. The acetabular cup prepared using this acetabular cup processing method involves creating a multi-filled porous metal acetabular cup skeleton using biodegradable metal materials. The skeleton is then uniformly mixed with the matrix material via ultrasonic vibration. After mixing, the mixture is formed under isostatic pressure. Finally, the formed material is sintered in a high-temperature oven. Each step contributes to increasing the strength of the acetabular cup implant. After the entire process is completed, the strength of the acetabular cup implant is significantly improved. Therefore, the acetabular cup implant can withstand higher load impacts during use, minimizing the risk of breakage, fracture, and other quality problems. This greatly improves the overall mechanical properties of the acetabular cup implant, ensuring its long-term stable use.

[0018] 2. The acetabular cup produced by this processing method has a high bone induction capacity. One reason is that the biodegradable zinc alloy used in the acetabular cup reacts with the body fluids in the human body to produce Zn ions. These ions can promote bone regeneration through three main strategies, including balancing osteoblasts and osteoclasts, regulating the immune microenvironment, and promoting bone angiogenesis, ultimately achieving a bone induction effect and thus accelerating the bone healing speed. Another type is the porous plastic structure left after the degradation of biodegradable metal materials, such as polyetheretherketone, ultra-high molecular weight polyethylene, or carbon fiber polyetheretherketone finished structures. The pore size and porosity of the porous plastic structure match the human cancellous bone. Bone generated by the stimulation of metal ions can grow into the pores, eventually allowing the prosthesis to integrate with the human bone, thereby achieving the bone induction effect. This further improves the bonding force between the acetabular cup and the bone, ensuring the long-term stable use of the acetabular cup. There is no need to spray bio-based coatings such as HA, Ti, or HA+Ti on the surface of the acetabular cup. Furthermore, this acetabular cup implant does not need to be used with bone cement, and will not damage surrounding tissues and nerves. It can avoid the problem of bone cement particles easily entering the pulmonary circulation through the bloodstream when using bone cement fixation.

[0019] 3. This acetabular cup implant is made by using a mixture of biodegradable metal materials and medical plastics as filling material. Compared with traditional acetabular cup implants made of metal materials, it is lighter in overall weight. The weight reduction can significantly reduce bone loss in patients and avoid a series of chain symptoms such as osteoporosis and bone calcification. Attached Figure Description

[0021] Figure 1 This is a three-dimensional view of the acetabular cup structure of the present invention; Figure 2 This is a three-dimensional view of the multi-pore metal acetabular cup skeleton structure of the present invention; Figure 3 This is a three-dimensional exploded view of the acetabular cup and biodegradable metal mesh of the present invention; Figure 4 This is the present invention. Figure 1 Enlarged view of point A in the middle; Figure 5 This is the present invention. Figure 2 Enlarged view of section B in the middle.

[0022] Explanation of symbols in the diagram 1. Multi-filled pore metal acetabular cup skeleton; 2. Acetabular liner fixing groove; 3. Support ring; 4. Second locking hole; 5. Biodegradable metal wire mesh; 6. First locking hole; 7. Positioning boss; 9. Wire; 10. Filling gap; 11. Rounded corner; 12. Acetabular liner fixing boss; 13. Third locking hole; 14. Fourth locking hole. Detailed Implementation

[0024] The present invention will be further described below with reference to embodiments.

[0025] pass Figures 1-5 It can be seen that the osteoinductive high-strength acetabular cup has a multi-filled porous metal acetabular cup skeleton 1, which is formed by interwoven wires 9, and filling pores 10 are formed between the interwoven wires 9. The wires 9 are biodegradable metal materials.

[0026] The pores 10 are filled with polymer material, and the outside of the multi-pore metal acetabular cup skeleton 1 is covered with a layer of polymer material.

[0027] The top of the multi-porosity metal acetabular cup skeleton 1 is provided with a first locking hole 6, and the middle position of the multi-porosity metal acetabular cup skeleton 1 is provided with a second locking hole 4. The first locking hole 6 and the second locking hole 4 pass through the polymer material covering the outside of the multi-porosity metal acetabular cup skeleton 1.

[0028] A positioning boss 7 is provided on the outer circumference of the first locking hole 6, and the positioning boss 7 protrudes outward along the top of the multi-filled pore metal acetabular cup skeleton 1.

[0029] During the surgical implantation, the acetabular cup fixation rod is inserted from inside the acetabular cup into the first locking hole 6. Then, holding the acetabular cup fixation rod, the acetabular cup is placed in the acetabular fossa. Then, with the help of external tools, the outer surface of the acetabular cup and the inner surface of the acetabular fossa are tightly fitted together. Then, the acetabular cup fixation rod is removed and fixed and locked to the acetabular bone by passing the locking screws through the first locking hole 6 and the second locking hole 4 respectively.

[0030] By setting a positioning boss 7 on the outer circumference of the first locking hole 6, the positioning boss 7 contacts the center of the acetabular fossa, which can play a good role in positioning and anti-slip. Specifically, if the positioning boss 7 is not set, after the top of the acetabular cup and the inside of the acetabular fossa are fitted together, the acetabular cup will inevitably shift or even fall off under its own weight or due to external impact, making it difficult to position the acetabular cup. The doctor will need to reinstall and position the acetabular cup, prolonging the operation time. However, by setting the positioning boss 7, the contact between the top of the acetabular cup and the inside of the acetabular fossa is changed from surface contact to line contact, which increases the friction between the acetabular cup and the acetabular fossa. The acetabular cup can be positioned quickly and accurately, shortening the operation time.

[0031] The bottom end of the multi-porosity metal acetabular cup skeleton 1 is provided with a downward-opening acetabular liner fixing groove 2, and the adjacent inner surface of the bottom end of the multi-porosity metal acetabular cup skeleton 1 is provided with an acetabular liner fixing boss 12. The positions of the acetabular liner fixing groove 2, the acetabular liner fixing boss 12 and the fixing buckle on the acetabular liner are matched with each other, which can increase the firmness between the acetabular liner and the acetabular cup 1 and avoid problems such as torsion, loosening or even falling off between the acetabular liner and the acetabular cup 1.

[0032] The lower end of the perforated metal acetabular cup skeleton 8 is provided with a support ring 3 located at the upper end of the acetabular liner fixing groove 2. The support ring 3 protrudes outward from the perforated metal acetabular cup skeleton 1.

[0033] After surgical implantation, the support ring 3 contacts the edge of the acetabular fossa. After the acetabular cup is implanted into the acetabular fossa, it forms a structure that is larger inside and smaller outside, thereby enhancing the stability of the acetabular cup in the human acetabulum. At the same time, the position near the bottom of the acetabular cup is a position that is prone to wear. The support ring 3 provides sufficient friction thickness between the acetabular cup and the acetabular fossa, so that the acetabular cup implant can be used stably for a long time.

[0034] Furthermore, the support ring 3 can increase the overall strength of the acetabular cup, increase its torsional and compressive resistance, and prevent the acetabular cup from being deformed by external forces.

[0035] The acetabular cup 1 is externally fixed with a biodegradable metal mesh 5, which is a porous mesh structure formed by interwoven wires 9.

[0036] The biodegradable metal mesh 5 is made from biodegradable metal wire or biodegradable metal powder, and the manufacturing process is wire weaving or 3D printing.

[0037] The top of the biodegradable metal wire mesh 5 is provided with a third locking hole 13, and the middle position of the biodegradable metal wire mesh 5 is provided with a fourth locking hole 14. The positions of the third locking hole 13 and the fourth locking hole 14 are symmetrical to the positions of the first locking hole 6 and the second locking hole 4, respectively.

[0038] A positioning boss 7 is provided on the outer circumference of the third locking hole 13, and the positioning boss 7 protrudes outward along the top of the biodegradable metal wire mesh 5.

[0039] There are four acetabular liner fixing grooves 2, which are evenly arranged along the bottom circumference of the multi-filled pore metal acetabular cup skeleton 1.

[0040] There are four acetabular liner fixing bosses 12, which are evenly arranged in the middle of two adjacent acetabular liner fixing grooves 2.

[0041] The external structure of the acetabular cup 1 and the biodegradable metal mesh 5 are secured by snap-fit ​​locking or screw locking.

[0042] The acetabular cup 1 and the biodegradable metal mesh 5 can also be fixed by embedded fixation, in which the biodegradable metal mesh 5 is embedded from the outside of the acetabular cup 1 into the inside, with an embedding depth of 0.5mm to 2mm.

[0043] Among them, the embedded fixation method is the most effective, which can increase the fitting accuracy between the acetabular cup and the biodegradable metal mesh and minimize the possibility of loosening between the acetabular cup and the biodegradable metal mesh.

[0044] Screw locking is characterized by its simple structure, diverse types, convenient assembly and disassembly, and low cost. In contrast, snap-locking offers several advantages. First, snaps can be directly pressurized onto the implant, eliminating the need for other locking components during assembly, thus simplifying operation and saving costs. Second, the connection strength of snaps meets the requirements of most product designs. In products requiring higher connection strength, snaps can serve as an auxiliary connection, such as a combination of screws and snaps. Third, with proper design, snap-lock connections allow for rapid assembly and disassembly, sometimes without the need for auxiliary tools. Snap-lock connections also further ensure the integrity of the implant's appearance and reduce wear. Especially in product areas with high aesthetic requirements, snap-lock connections are the most widely used connection method.

[0045] The embedding depth is consistent with the depth of the hole in the finished acetabular cup after the biodegradable metal has completely degraded. For example, if the embedding depth is 2mm, then the depth of the hole in the finished acetabular cup is also 2mm. The depth of the hole is the depth to which bone tissue grows in. For areas with severe bone damage, the embedding depth is usually increased to ensure that the bone tissue has sufficient ingrowth depth, thereby ensuring the long-term stability of the implant.

[0046] The outer surface of the acetabular cup is smoothly transitioned with rounded corners, which can prevent damage to bone tissue caused by the sharp outer surface of the acetabular cup.

[0047] A method for preparing the above-mentioned biodegradable zinc alloy reinforced polymer acetabular cup and its processing includes preparing a reinforcing material and a matrix material. The reinforcing material is a biodegradable metallic material, and the matrix material is a polymer material. The processing method includes the following steps: Step (1): Prepare a multi-filled porous metal acetabular cup skeleton 1 from biodegradable metal material.

[0048] Step (2): Place the prepared multi-filled porous metal acetabular cup skeleton 1 and polymer material into the cavity mold respectively. Use vibration to uniformly fill the filling pores 10 of the multi-filled porous metal acetabular cup skeleton with polymer material. Then, press the uniformly mixed material through the cavity mold to form a semi-finished acetabular cup.

[0049] Step (3): Place the semi-finished acetabular cup into a high-temperature oven for sintering. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

[0050] Example 1 When the reinforcing material is biodegradable magnesium alloy powder and the matrix material is polyetheretherketone powder, the processing method includes the following steps: Step (1): Biodegradable magnesium alloy powder is used to prepare a multi-pore magnesium alloy acetabular cup skeleton by 3D printing.

[0051] The particle size of biodegradable magnesium alloy powder is 50μm-68μm, the particle size of polyetheretherketone powder is 63μm-80μm, and the pore size of the multi-porosity magnesium alloy acetabular cup skeleton is 62μm-81μm with a porosity of 52%-68%.

[0052] Step (2): Place the prepared multi-filled porous magnesium alloy acetabular cup skeleton into the cavity mold, and then fill the cavity mold with polyether ether ketone powder. The filling method is to fill in equal amounts multiple times, and the number of equal amounts is five times. After each filling, the polyether ether ketone powder is evenly filled into the filling pores 10 of the multi-filled porous magnesium alloy acetabular cup skeleton by vibration. The vibration method is mechanical vibration or ultrasonic vibration, and the vibration time is 22 min - 33 min. The difference between ultrasonic vibration and mechanical vibration is that the uniformity of ultrasonic vibration is higher than that of mechanical vibration. When the mixing accuracy requirement is high, ultrasonic vibration is usually used, while mechanical vibration is used instead.

[0053] After uniform filling, the mixed material is pressurized and molded through a cavity mold. The pressing method is vacuum hot isostatic pressing or vacuum cold isostatic pressing. The pressure is 88MPa-108MPa and the holding time is 15min-25min. After pressing and molding, a semi-finished acetabular cup is obtained.

[0054] Isostatic pressing ensures uniform and consistent density of the pressed blank, resulting in a high blank density. Furthermore, due to the high blank density, the shrinkage during sintering is small, and the blank is not easily deformed after sintering, thus ensuring the structural stability of the blank. Moreover, isostatically pressed blanks have high strength and can be directly handled and machined. More importantly, the internal stress of the blank is small, reducing defects such as cracking and delamination.

[0055] Step (3): Place the semi-finished acetabular cup into a high-temperature oven for sintering. The sintering methods are hot pressing sintering, vacuum hot isostatic pressing sintering, gas pressure sintering, microwave sintering, spark plasma sintering or solid metal sintering. The sintering temperature is 280℃-360℃ and the sintering time is 33 min-48 min. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

[0056] Hot pressing sintering refers to the sintering process in which materials are accelerated to flow, rearrange, and densify under a certain external force (generally 10-40 MPa depending on the strength of the mold material). The temperature required for hot pressing sintering is 100-150℃ lower than that for atmospheric pressure sintering, but the driving force for hot pressing sintering is 20-100 times greater than that for atmospheric pressure sintering.

[0057] Hot pressing sintering can achieve better mechanical properties of materials, and can reduce sintering time or sintering temperature, reduce the amount of covalent ceramic sintering aids, thereby improving the high-temperature mechanical properties of materials.

[0058] The basic principle of vacuum hot isostatic pressing is to use high-pressure gas as a pressure medium to act on the material (including encapsulated powder, green body or sintered body), so that it is subjected to uniform pressure in all directions during the heating process, and the material is densified by the combined action of high temperature and high pressure.

[0059] Hot isostatic pressing (HIP) can reduce sintering temperature and shorten sintering time. At the same time, it can greatly reduce or even eliminate the use of sintering aids, improve ceramic performance and reliability, and is particularly suitable for manufacturing products with complex shapes.

[0060] Gas pressure sintering refers to applying a certain gas pressure during the high-temperature sintering process. The pressure range is usually 1-10 MPa, in order to suppress the decomposition and weight loss of the material at high temperatures, thereby increasing the sintering temperature and further promoting the densification of the material to obtain high-density products. Gas pressure sintering and vacuum hot isostatic pressing both use gas as a method to transmit pressure.

[0061] Compared with hot pressing sintering and vacuum hot isostatic pressing sintering, the biggest advantage of gas pressure sintering is that it can reduce input costs, produce products with better performance, is suitable for products with complex shapes, and can achieve mass production.

[0062] Microwave sintering is commonly used for sintering ceramic materials. It utilizes the dielectric loss of the ceramic material in the microwave electromagnetic field to bring the material to the sintering temperature, thereby achieving the sintering and densification of the ceramic.

[0063] Spark plasma sintering, also known as "plasma-activated sintering," is a novel material preparation technology that achieves material sintering through thermal effects or other field effects by directly applying a large pulse current to a mold or sample.

[0064] Spark plasma sintering can ensure uniform heating temperature, rapid heating rate, low sintering temperature, short sintering time, high production efficiency, fine and uniform product structure, maintain the natural state of raw materials, and obtain high-density materials. It is commonly used in sintering gradient materials and complex workpieces.

[0065] Solid-state metal sintering is a sintering process that uses powdered materials. These powdered materials can be molded into the desired shapes, enabling the production of complex and intricately designed parts. Furthermore, solid-state sintering can improve the mechanical properties of materials. Compared to traditional processes, solid-state sintering has a shorter cycle time, meaning the sintering process can be completed in minutes instead of hours or longer. This high productivity and rapid material development capability have led to the wider application of solid-state metal sintering.

[0066] More importantly, solid-state metal sintering can be carried out at lower temperatures compared to traditional sintering processes, which is a significant advantage as it helps to minimize energy consumption and reduce the risk of thermal damage to the sintered materials. Furthermore, solid-state metal sintering is an extremely versatile process that can be used for densification sintering of low-melting-point metals and ultra-high-temperature ceramics, and even for bonding dissimilar materials that require non-uniform temperatures. In addition, solid-state sintering can also be used to sinter porous and fully dense components, making its applications very broad.

[0067] In summary, solid-state metal sintering offers numerous advantages, including the ability to produce complex shapes, better mechanical properties, shorter sintering time, lower sintering temperature, versatility, high-precision process control, and cost-effectiveness. These advantages make solid-state sintering an ideal manufacturing method for widespread applications.

[0068] In Example 1, the particle size of the biodegradable magnesium alloy powder in step (1) is 60 μm, the particle size of the polyether ether ketone powder is 70 μm, and the pore size of the multi-pore magnesium alloy acetabular cup skeleton is 75 μm with a porosity of 60%.

[0069] The oscillation method in step (2) is ultrasonic oscillation, and the oscillation time is 30 minutes.

[0070] The pressure molding method in step (2) is vacuum hot isostatic pressing, with a pressure of 100 MPa and a holding time of 20 min. The sintering method in step (3) is vacuum hot isostatic pressing sintering, the sintering temperature is 330℃, and the sintering time is 40min.

[0071] The particle size range of the biodegradable metal powder is within the standard parameters for conventional 3D printing.

[0072] Example 2 When the reinforcing material is biodegradable zinc alloy wire and the matrix material is ultra-high molecular weight polyethylene powder, the processing method includes the following steps: Step (1): The biodegradable zinc alloy wire is used to prepare a multi-pore zinc alloy acetabular cup skeleton by wire weaving.

[0073] The diameter of the biodegradable zinc alloy wire is 490μm-620μm, and the particle size of the ultra-high molecular weight polyethylene powder is 60μm-82μm.

[0074] The pore size of the multi-filled porous zinc alloy acetabular cup skeleton is 71μm-86μm, and the porosity is 61%-75%.

[0075] Step (2): Place the prepared multi-filled porous zinc alloy acetabular cup skeleton into the cavity mold, and then fill the cavity mold with ultra-high molecular weight polyethylene powder. The filling method is to fill in equal amounts multiple times, and the number of equal amounts is five. After each filling, the ultra-high molecular weight polyethylene powder is evenly filled into the filling pores 10 of the multi-filled porous zinc alloy acetabular cup skeleton by vibration. The vibration method is mechanical vibration or ultrasonic vibration, and the vibration time is 22min-34min. After uniform filling, the mixed material is pressurized and formed by the cavity mold. The pressurization method is vacuum hot isostatic pressing or vacuum cold isostatic pressing. The pressurization pressure is 110MPa-175MPa, and the holding time is 22min-35min. After pressurization and forming, the acetabular cup semi-finished product is obtained.

[0076] Using multiple equal-volume fillings ensures that the matrix material powder and the multi-filled porous metal acetabular cup skeleton are fully and evenly filled, avoiding inconsistent density in different locations, which can lead to lower compressive strength of the prosthesis, or even problems such as cracking and delamination. The filling number of 5 times is the filling number obtained through a large number of experiments. It can ensure the filling density inside the prosthesis, ensure that the prosthesis has sufficient compressive strength, reduce internal stress, and save processing time.

[0077] Step (3): The semi-finished acetabular cup is placed in a high-temperature oven for sintering. The sintering method is hot pressing sintering, vacuum hot isostatic pressing sintering, gas pressure sintering, microwave sintering, spark plasma sintering or solid metal sintering. The sintering temperature is 305℃-365℃ and the sintering time is 0.6h-1.2h. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

[0078] In Example 2, the biodegradable zinc alloy wire in step (1) has a diameter of 550 μm, the polyether ether ketone powder has a particle size of 75 μm, and the multi-pore zinc alloy acetabular cup skeleton has a pore size of 80 μm and a porosity of 70%.

[0079] The oscillation method in step (2) is ultrasonic oscillation, and the oscillation time is 30 minutes.

[0080] The pressure molding method in step (2) is vacuum hot isostatic pressing, with a pressure of 150 MPa and a holding time of 30 min.

[0081] The sintering method in step (3) is vacuum hot isostatic pressing sintering, the sintering temperature is 340℃, and the sintering time is 1h.

[0082] The diameter parameters of biodegradable metal wires are similar to the porosity of human bone tissue, which is conducive to bone ingrowth.

[0083] Multi-filled porous metal acetabular cup skeletons were fabricated using a combination of wire weaving and 3D printing. Wire weaving is less expensive but has greater limitations in designing a range of parameters for porous metal materials. In contrast, 3D printing offers greater flexibility in adjusting the shape, size, and porosity of the pores, allowing for targeted adjustments based on the patient's imaging data to achieve the most suitable implantation effect. Therefore, 3D printing is chosen when high requirements are placed on the prosthesis's structural parameters, while wire weaving is preferred when the requirements are less stringent and cost savings are a consideration.

[0084] In this processing method, biodegradable zinc alloy materials and biodegradable magnesium alloy materials are used. These materials react with body fluids in the human body and are gradually corroded and degraded by the body fluids. Specifically, when biodegradable zinc alloy materials and biodegradable magnesium alloy materials react with body fluids, they produce magnesium ions or zinc ions. These two ions are the most important trace elements in bone tissue and are indispensable active components in human biological activities. They play an important role in bone tissue repair and can effectively accelerate the fusion speed and fusion effect of bone injury sites, thus promoting the recovery of bone injury sites.

[0085] The acetabular cup implant is made by using biodegradable metal materials to prepare a multi-filled porous metal acetabular cup skeleton. Then, the multi-filled porous metal acetabular cup skeleton and the matrix material are uniformly filled and mixed by ultrasonic vibration. After mixing, it is formed by isostatic pressing. Finally, the formed material is placed in a high-temperature oven for sintering to obtain the finished acetabular cup.

[0086] It is evident that each step contributes to increasing the strength of the acetabular cup implant. After the entire process is completed, the strength of the acetabular cup implant is significantly enhanced. As a result, the acetabular cup implant can withstand higher load impact forces during use, minimizing the risk of damage, breakage, and other quality problems during use. This greatly improves the overall mechanical properties of the acetabular cup implant and ensures its long-term stable use.

[0087] Furthermore, the acetabular cup produced by this processing method exhibits significant osteoinductive capabilities. The specific osteoinductive effect depends on two aspects. First, the biodegradable metal materials used in the acetabular cup, such as biodegradable magnesium alloys and zinc alloys, react with bodily fluids in the human body, producing Mg and Zn ions. These ions promote bone regeneration through three main strategies: balancing osteoblasts and osteoclasts, regulating the immune microenvironment, and promoting bone angiogenesis, ultimately achieving the osteoinductive effect. Second, the porous plastic structure left after the degradation of the biodegradable metal materials, such as polyetheretherketone (PEEK), ultra-high molecular weight polyethylene (UHMWPE), or carbon fiber PEEK, matches the pore size and porosity of human cancellous bone. Bone stimulated by metal ions can grow into these pores, ultimately allowing the prosthesis to integrate with the human bone, thus achieving the osteoinductive effect.

[0088] More importantly, the osteoinductive high-strength acetabular cup prepared using this processing method is made by mixing different types of reinforcing and matrix materials. For example, the reinforcing material can be biodegradable metal wire or biodegradable metal powder, and the matrix material can be polyetheretherketone powder, ultra-high molecular weight polyethylene powder, or carbon fiber polyetheretherketone composite material. Each reinforcing and matrix material has its own fixed preparation parameter values, such as the diameter and particle size of the reinforcing material, the particle size of the matrix material, and the pore size and porosity of the prepared multi-filled porous metal acetabular cup skeleton. Then, the selected reinforcing and matrix materials are uniformly mixed, pressurized, sintered, and other preparation processes to obtain the osteoinductive high-strength acetabular cup.

[0089] Furthermore, the aforementioned preparation processes each have strict and specific preparation parameters and processes, such as the pressure molding method, the sintering method, sintering temperature, and sintering time. These preparation parameters and processes are key to preparing a high-strength acetabular cup material with osteoinductive properties.

[0090] Secondly, this acetabular cup implant is made by using a mixture of biodegradable metal materials and medical plastics as filling material. Compared with traditional acetabular cup implants made of metal materials, it is lighter in overall weight. The weight reduction can significantly reduce bone loss in patients and avoid a series of chain symptoms such as osteoporosis and bone calcification.

[0091] Example 3 The interior of the finished acetabular cup material can be prepared solely from polyetheretherketone powder, ultra-high molecular weight polyethylene powder, or carbon fiber polyetheretherketone composite material. The specific method is as follows: Step (1): Prepare biodegradable metal materials and matrix materials, and prepare the biodegradable metal materials into a multi-filled porous metal acetabular cup shell skeleton. The interior of the multi-filled porous metal acetabular cup shell skeleton is a hollow structure. The preparation process is wire weaving or 3D printing.

[0092] The biodegradable metal material is biodegradable metal wire or biodegradable metal powder, and the matrix material is polyetheretherketone powder, ultra-high molecular weight polyethylene powder or carbon fiber polyetheretherketone composite material.

[0093] Step (2): Place the prepared multi-filled porous metal acetabular cup shell skeleton into the cavity mold, and then fill the cavity mold with polyetheretherketone powder, ultra-high molecular weight polyethylene powder or carbon fiber polyetheretherketone composite material. The filling method is to fill in equal amounts multiple times. After each filling is completed, the polyetheretherketone powder, ultra-high molecular weight polyethylene powder or carbon fiber polyetheretherketone composite material is uniformly filled into the interior of the multi-filled porous metal acetabular cup shell skeleton through the pores of the multi-filled porous metal acetabular cup shell skeleton by ultrasonic vibration until it is full.

[0094] Step (3): After filling, the mixed material is pressed and molded through a cavity mold. After pressing and molding, a semi-finished acetabular cup is obtained.

[0095] Step (4): Place the semi-finished acetabular cup into a high-temperature oven for sintering. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

[0096] The acetabular cup implant produced by this processing method has lower strength compared to the acetabular cup implants prepared by mixing a multi-filled porous metal acetabular cup skeleton and a matrix material in Examples 1 and 2. This acetabular cup implant can be used for patients with low postoperative activity. If the patient has high postoperative activity, the acetabular cup implant prepared by mixing a porous metal acetabular cup skeleton and a matrix material in Examples 1 and 2 is still required to meet the requirements of high support force and the ability to withstand high impact force in the relevant area, and further ensure the long-term stable use of the acetabular cup implant.

[0097] However, the above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made in accordance with the scope of protection of the present invention should still fall within the scope of the claims of the present invention.

Claims

1. A processing method for a biodegradable zinc alloy reinforced polymer acetabular cup, characterized in that: The process involves preparing a reinforcing material and a matrix material, wherein the reinforcing material is a biodegradable zinc alloy wire, and the matrix material is ultra-high molecular weight polyethylene powder. The processing method includes the following steps: Step (1): The biodegradable zinc alloy wire is used to prepare a multi-pore zinc alloy acetabular cup skeleton, and the processing method is wire weaving; The biodegradable zinc alloy wire has a diameter of 490μm-620μm, the ultra-high molecular weight polyethylene powder has a particle size of 60μm-82μm, and the multi-pore zinc alloy acetabular cup skeleton has a pore size of 71μm-86μm and a porosity of 61%-75%. Step (2): Place the prepared multi-filled porous zinc alloy acetabular cup skeleton into the cavity mold, and then fill the cavity mold with ultra-high molecular weight polyethylene powder. The filling method is to fill in the same amount multiple times, and the number of times the equal amount filling is five. After each filling, the ultra-high molecular weight polyethylene powder is evenly filled into the filling pores of the multi-filled porous zinc alloy acetabular cup skeleton by vibration. The vibration method is mechanical vibration or ultrasonic vibration, and the vibration time is 22min-34min. After uniform filling, the mixed material is pressurized and formed by the cavity mold. The pressing method is vacuum hot isostatic pressing or vacuum cold isostatic pressing. The pressure is 110MPa-175MPa, and the holding time is 22min-35min. After pressing and forming, the acetabular cup semi-finished product is obtained. Step (3): The semi-finished acetabular cup is placed in a high-temperature oven for sintering. The sintering method is hot pressing sintering, vacuum hot isostatic pressing sintering, gas pressure sintering, microwave sintering, spark plasma sintering or solid metal sintering. The sintering temperature is 305℃-365℃ and the sintering time is 0.6h-1.2h. After sintering, a high-strength acetabular cup with osteoinductive properties is obtained.

2. The processing method of the biodegradable zinc alloy reinforced polymer acetabular cup according to claim 1, characterized in that: The biodegradable zinc alloy wire in step (1) has a diameter of 550 μm, the polyether ether ketone powder has a particle size of 75 μm, and the multi-pore zinc alloy acetabular cup skeleton has a pore size of 80 μm and a porosity of 70%. The oscillation method in step (2) is ultrasonic oscillation, and the oscillation time is 30 minutes; The pressure molding method in step (2) is vacuum hot isostatic pressing molding, with a pressure of 150MPa and a holding time of 30min. The sintering method in step (3) is vacuum hot isostatic pressing sintering, the sintering temperature is 340℃, and the sintering time is 1h.

3. A biodegradable zinc alloy reinforced polymer acetabular cup processed using the processing method described in any one of claims 1 or 2, characterized in that: A multi-porosity metal acetabular cup skeleton is provided, which is formed by interwoven wires, and the interwoven wires form filling pores. The wires are made of biodegradable metal material. The pores are filled with polymer material, and the outside of the multi-pore metal acetabular cup skeleton is covered with a layer of polymer material. The top of the multi-filled porous metal acetabular cup skeleton is provided with a first locking hole, and the middle position of the multi-filled porous metal acetabular cup skeleton is provided with a second locking hole. The first locking hole and the second locking hole pass through the polymer material covering the outside of the multi-filled porous metal acetabular cup skeleton. A positioning boss is provided on the outer circumference of the first locking hole, and the positioning boss protrudes outward along the top of the multi-filled pore metal acetabular cup skeleton; The bottom end of the multi-filled porous metal acetabular cup skeleton is provided with a downward-opening acetabular liner fixing groove, and the adjacent inner surface of the bottom end of the multi-filled porous metal acetabular cup skeleton is provided with an acetabular liner fixing boss. Biodegradable metallic materials are corroded and degraded by body fluids in the body, leaving behind a polymer structure that creates space for bone tissue ingrowth. The polymer material is a mixture of biodegradable zinc alloy wire and ultra-high molecular weight polyethylene powder.

4. The biodegradable zinc alloy reinforced polymer acetabular cup according to claim 3, characterized in that: The lower end of the multi-filled porous metal acetabular cup skeleton is provided with a support ring located at the upper end of the acetabular liner fixing groove, and the support ring protrudes outward from the multi-filled porous metal acetabular cup skeleton.

5. The biodegradable zinc alloy reinforced polymer acetabular cup according to claim 3, characterized in that: The acetabular cup is externally fixed with a biodegradable metal mesh, which has a porous mesh structure and is formed by interwoven wires. The external structure of the acetabular cup and the biodegradable metal mesh are fixed by snap-fit ​​locking or screw locking. The biodegradable metal wire mesh has a third locking hole at its top and a fourth locking hole at its middle position. The positions of the third and fourth locking holes are symmetrical to the positions of the first and second locking holes, respectively. A positioning boss is provided on the outer circumference of the third locking hole, and the positioning boss protrudes outward along the top of the biodegradable metal wire mesh.

6. The biodegradable zinc alloy reinforced polymer acetabular cup according to claim 3, characterized in that: The number of the acetabular liner fixing grooves is four, and the four acetabular liner fixing grooves are evenly arranged along the bottom circumferential direction of the multi-filled pore metal acetabular cup skeleton. The number of acetabular liner fixing bosses is four, and the four acetabular liner fixing bosses are evenly arranged in the middle position of two adjacent acetabular liner fixing grooves.

7. The biodegradable zinc alloy reinforced polymer acetabular cup according to claim 3, characterized in that: The outer surface of the acetabular cup is smoothly transitioned by rounded corners.

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