A single ankle joint clinical surgical surface replacement system

Abstract

The application provides a single ankle joint clinical operation surface replacement system and belongs to the field of medical instruments. The single ankle joint clinical operation surface replacement system comprises a lateral tibial tray, an intermediate pad and a lateral talus top. The top of the lateral tibial tray is provided with the intermediate pad. The side, away from the lateral tibial tray, of the intermediate pad is provided with the lateral talus top. The side wall, close to the lateral talus top, of the intermediate pad is concave. The surface of the lateral tibial tray is provided with connecting grooves on both sides. The end, close to the lateral tibial tray, of the intermediate pad is arranged with a connecting strip. The connecting strip is matched with the connecting grooves. The connecting strip is embedded in the connecting grooves. The inner wall edges of the connecting grooves are arranged with limiting grooves. The limiting grooves are embedded with a first shape memory polymer. After the fixed connection of the lateral tibial tray and the intermediate pad, the first shape memory polymer is expanded to fill the gap between the connecting strip and the connecting grooves to form a rigid connection, thereby improving the stability of the connection.

Description

Technical Field

[0001] This invention relates to the field of medical devices, and more specifically, to a single ankle joint clinical surgical surface replacement system. Background Technology

[0002] Currently, ankle arthroplasty and total ankle replacement are the mainstream surgical procedures for treating end-stage ankle joint diseases such as traumatic arthritis, osteoarthritis, and rheumatoid arthritis. However, patients undergoing ankle arthroplasty often experience poor joint function post-surgery. Therefore, total ankle replacement has become a more popular treatment option, and its application is gradually increasing. Currently, all artificial ankle joints used clinically are total ankle replacements, meaning that the distal tibia and proximal talus articular surfaces are completely replaced. However, many patients' ankle degeneration, cartilage defects or injuries, and pain mainly stem from damage to certain articular surfaces, such as the medial articular surface, lateral articular surface, or locally necrotic articular surfaces of the talus. Replacing relatively normal articular surfaces is highly destructive. Furthermore, total ankle replacements also have many problems, such as prosthesis loosening, limited lifespan, and displacement of the movable pad. Revision surgery for failed total ankle replacements also presents challenges such as bone loss and difficulties in reconstruction. Based on the aforementioned technical problems, existing technologies have also provided some solutions. For example, Chinese Patent No. CN109620483A discloses a single ankle joint surface replacement system. This system consists of a tibial surface, a rotational nucleus, and a talar surface. The tibial and talar surfaces are made of metal or alloy materials, while the rotational nucleus is made of abrasion-resistant polyethylene material. Using this structure, single ankle joint surface replacement can be achieved. The anterior part of the tibial surface is angularly connected to the sagittal part of the body. The top of the tibial surface is a rough-coated surface or a non-polished metal surface; the bottom of the tibial surface is a polished smooth surface. The middle part of the body has a double-fin-like keel. The lateral and anteroposterior diameters of the rotational nucleus are smaller than those of the tibial surface; the top of the rotational nucleus is convex in both sagittal and coronal planes, and the bottom of the rotational nucleus is a horizontal smooth plane. The top of the talar surface is a polished horizontal smooth surface, the bottom is a non-polished metal surface, and the middle part of the bottom has a double-fin-like keel. This system is simple in structure, easy to use, achieves good ankle joint function, effectively preserves bone volume, effectively improves initial stability, and reduces revision rate.

[0003] However, in actual production operations, existing single ankle joint replacement systems are prone to pad dislocation when sliding the intermediate pad and the lateral tibial plate. When fixing the connection, they are often fixed by a simple locking structure or by bolts. During long-term exercise, the bolts are prone to loosening, resulting in an unstable connection. Summary of the Invention

[0004] In view of the problem that the existing feeding devices cannot be adjusted according to the feeding needs of steel bars of different lengths and specifications, and can only feed steel bars of fixed lengths, the purpose of this invention is to provide a single ankle joint clinical surgical surface replacement system.

[0005] To solve the above problems, the present invention adopts the following technical solution:

[0006] A single ankle joint clinical surgical surface replacement system includes a lateral tibial tray, an intermediate pad, and a lateral talus top; the intermediate pad is disposed on the top of the lateral tibial tray, and the lateral talus top is disposed on the side of the intermediate pad away from the lateral tibial tray.

[0007] The outer wall of the intermediate pad near the top of the lateral talus is concave, and the side of the top of the lateral talus near the intermediate pad is slidably connected to the concave surface. The side of the top of the lateral talus near the intermediate pad is a smooth surface, and the side of the top of the lateral talus away from the intermediate pad is a rough surface.

[0008] It also includes connecting grooves on both sides of the surface of the tibial tray, with connecting strips arranged and connected at one end of the middle pad near the tibial tray. The connecting strips match the connecting grooves and are embedded in the connecting grooves. Limiting grooves are arranged at the inner edge of the connecting grooves, and a No. 1 shape memory polymer is embedded inside the limiting grooves.

[0009] Optionally, a connecting assembly is provided in the middle of the lateral tibial tray. The connecting assembly includes a connecting groove, a top rod, a top block, an inclined block, and a fixing hole. The connecting groove is connected to the connecting grooves on both sides, and the inner walls on both sides of the connecting groove are slidably connected to the top rod. The ends of the two sets of top rods that are far apart are connected to the top block, and the ends of the two sets of top rods that are opposite each other are connected to the inclined block. The two sets of inclined blocks abut against each other, and a fixing hole is provided on one outer wall of the top block.

[0010] Optionally, a threaded groove is provided in the middle of the two sets of connecting grooves, the end of the threaded groove is connected to the connecting groove, and a fastening bolt is threadedly connected to the inner wall of the middle of the threaded groove.

[0011] Optionally, a slot is provided on one side of the outer wall of both sets of connecting strips, and the top blocks of both sets match the slots on both sides. A second shape memory polymer is embedded on one side of the inner wall of the slot, and the second shape memory polymer matches the fixing hole.

[0012] Optionally, each of the four ends of the lateral talus bone top is provided with an oblique locking pin hole. The oblique locking pin hole is threaded inside, and the pin hole direction is at a 40° angle to the horizontal plane. The rough surface of the lateral talus bone top is generated with a gradient porous titanium structure by laser cladding technology. The porosity gradually changes from 80% to 30% from the surface to the inside, and the pore size is 50-500μm.

[0013] Optionally, a piezoelectric sensor is embedded in the center of the intermediate pad, and an RFID sensor is provided on one side of the piezoelectric sensor. The outer walls of both the piezoelectric sensor and the RFID sensor are covered with silicone pads.

[0014] Optionally, the intermediate liner is made of vitamin E-doped highly cross-linked polyethylene, and the lateral tibial tray and the lateral talus top are both made of titanium alloy.

[0015] Optionally, the tibial tray has a mounting connection hole at its center, and positioning posts are provided at all four ends of the outer wall of the tibial tray on the side away from the intermediate pad. Micro-holes are arranged on the outer wall of the tibial tray on the side near the positioning posts.

[0016] Optionally, both the first shape memory polymer and the second shape memory polymer are made of polyurethane-based shape memory polymers.

[0017] Optionally, the bone contact surfaces of the lateral tibial tray and the lateral talus top are coated with a gradient bioactive coating, wherein the gradient bioactive coating consists of, from the inside out:

[0018] Inner layer: Hydroxyapatite, 80wt%, balance is titanium alloy substrate material, thickness 50μm;

[0019] Intermediate layer: strontium-doped hydroxyapatite, 50 wt%, balance is titanium alloy substrate material, 30 μm thick;

[0020] Outer layer: Mesoporous silica nanoparticle layer containing bone morphogenetic protein-2, 20 μm thick.

[0021] Compared with the prior art, the technical solution provided by this invention has at least the following beneficial effects:

[0022] In the above solution, after the lateral tibial tray and the intermediate pad are fixedly connected, the No. 1 shape memory polymer expands at 37°C to fill the gap between the connecting strip and the connecting groove, forming a rigid connection, thereby improving the stability of the connection. At the same time, the No. 2 shape memory polymer expands at 37°C to fill the fixing hole, realizing the fixed positioning of the top block. The top block snap-fit, in conjunction with the No. 1 shape memory polymer, achieves a double stable connection between the connecting strip and the connecting groove, preventing the connection from loosening under long-term wear. Meanwhile, the No. 2 shape memory polymer can fill the fixing hole to fix and limit the top block after connection, preventing the bolts from loosening and causing the top block to separate from the slot, thus improving the stability of the connection between the lateral tibial tray and the intermediate pad. Even if the bolts loosen, it will not affect its rigid connection.

[0023] The pressure signal is converted into an electric charge signal by a piezoelectric sensor, and then stored or transmitted after analog-to-digital conversion by an RFID chip. The RFID sensor model is ST25TV02KC. ​​It integrates a piezoresistive sensor to monitor the thickness change of the intermediate pad 2 and monitors the wear rate of the pad in real time. If the wear rate exceeds the threshold, it prompts the doctor to adjust the rehabilitation plan or intervene in advance.

[0024] The bone contact surfaces of the lateral tibial tray and the lateral talus top are coated with a gradient bioactive coating. The outer layer, BMP-2, induces osteoprogenitor cell aggregation to form callus, the middle layer, Sr-HA, promotes mineralization, and the inner layer, HA, guides osteoogenesis, achieving complete integration of the bone interface and mechanical strength at physiological levels. The gradient coating, through a three-in-one design of bone induction, osteoconduction, and bone metabolism regulation, precisely controls the bone regeneration process at different stages after surgery, while simultaneously addressing core clinical issues such as infection, loosening, and stress shielding, thereby improving the bone integration efficiency and long-term stability of the ankle joint prosthesis. Attached Figure Description

[0025] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments of the invention and, together with the specification, further serve to explain the principles of the invention and enable those skilled in the art to practice and use the invention.

[0026] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0027] Figure 2 For the present invention Figure 1 A schematic diagram of the decomposed structure;

[0028] Figure 3 This is a schematic diagram of the system installation and connection structure of the present invention;

[0029] Figure 4 This is a top view schematic diagram of the lateral tibial tray structure of the present invention;

[0030] Figure 5 This is a schematic diagram of the connection structure between the lateral tibial tray and the intermediate pad of the present invention;

[0031] Figure 6 This is a schematic diagram of the connection component structure of the present invention;

[0032] Figure 7 This is a schematic diagram of the connection structure between the top block and the slot of the present invention;

[0033] Figure 8 This is a front view structural diagram of the present invention.

[0034] [Figure Labels]

[0035] 1. Lateral tibial tray; 2. Intermediate pad; 3. Lateral talus top;

[0036] 201. Concave surface;

[0037] 4. Connecting groove; 401. Limiting groove; 402. Shape memory polymer No. 1;

[0038] 5. Connecting strip;

[0039] 6. Connecting components; 601. Connecting groove; 602. Top rod; 603. Top block; 604. Inclined block; 605. Fixing hole;

[0040] 7. Threaded groove; 8. Fastening bolt; 9. Slot; 901. Shape memory polymer No. 2;

[0041] 6. Non-powered material feeding mechanism; 61. No. 2 motor; 62. Limit slot; 63. Rotating shaft; 64. Mounting cylinder; 65. Lower limit rod; 66. Upper limit rod; 67. Common rotating block; 68. Telescopic groove; 69. Telescopic sleeve rod;

[0042] 10. Angled locking pin holes;

[0043] 11. Piezoelectric sensor; 12. RFID sensor; 13. Silicone pad;

[0044] 14. Mounting connection hole; 15. Positioning post; 16. Micro-hole; 17. Gradient bioactive coating.

[0045] As shown in the figure, specific structures and devices are marked in the figure to clearly illustrate the structure of the embodiments of the present invention. However, this is only for illustrative purposes and is not intended to limit the present invention to this specific structure, device and environment. Those skilled in the art can adjust or modify these devices and environments according to specific needs. Detailed Implementation

[0046] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. It should also be noted that, to make the embodiments more comprehensive, the following embodiments are the best and preferred embodiments, and those skilled in the art can use other alternative methods to implement some well-known technologies; moreover, the accompanying drawings are only for more specific description of the embodiments and are not intended to specifically limit the present invention.

[0047] It should be noted that the use of terms such as "an embodiment," "an embodiment," "an exemplary embodiment," and "some embodiments" in the specification indicates that the described embodiment may include a specific feature, structure, or characteristic, but not every embodiment necessarily includes that specific feature, structure, or characteristic. Furthermore, when a specific feature, structure, or characteristic is described in connection with an embodiment, implementing such a feature, structure, or characteristic in conjunction with other embodiments (whether explicitly described or not) should be within the knowledge of those skilled in the art.

[0048] Generally, terms can be understood at least partly from their use in context. For example, depending at least partly on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or a combination of features, structures, or characteristics in a plural sense. Additionally, the term "based on" can be understood not necessarily to convey an exclusive set of factors, but rather, alternatively, depending at least partly on the context, to allow for the presence of other factors that are not necessarily explicitly described.

[0049] It is understood that the meanings of “on”, “above”, and “above” in this invention should be interpreted in the broadest manner, such that “on” means not only “directly on” something, but also includes the meaning of being “on” something with an intervening feature or layer, and that “above” or “above” means not only “on” something, but also includes the meaning of being “on” something without an intervening feature or layer.

[0050] Furthermore, spatially related terms such as “below,” “under,” “lower,” “above,” and “upper” are used herein for convenience to describe the relationship of one element or feature to one or more other elements or features, as illustrated in the accompanying drawings. Spatially related terms are intended to cover different orientations in the use or operation of the device other than those depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially related descriptive terms used herein can be interpreted similarly.

[0051] like Figures 1 to 8 As shown, this embodiment of the invention provides a single ankle joint clinical surgical surface replacement system, including a lateral tibial tray 1, an intermediate pad 2, and a lateral talus top 3; the intermediate pad 2 is disposed on the top of the lateral tibial tray 1, and the lateral talus top 3 is disposed on the side of the intermediate pad 2 away from the lateral tibial tray 1.

[0052] The outer wall of the intermediate pad 2 near the lateral talus top 3 is a concave surface 201. The side of the lateral talus top 3 near the intermediate pad 2 is slidably connected to the concave surface 201. The side of the lateral talus top 3 near the intermediate pad 2 is a smooth surface, and the side of the lateral talus top 3 away from the intermediate pad 2 is a rough surface.

[0053] It also includes connecting grooves 4 on both sides of the surface of the tibial tray 1. Connecting strips 5 are arranged and connected at one end of the middle pad 2 near the tibial tray 1. The connecting strips 5 match the connecting grooves 4 and are embedded in the connecting grooves 4. Limiting grooves 401 are arranged at the inner edge of the connecting grooves 4. A shape memory polymer 402 is embedded inside the limiting grooves 401.

[0054] The lateral tibial tray 1 serves as the tibial end fixation base for the prosthesis, fixing the tibial joint and connecting with the intermediate pad 2. Both the lateral tibial tray 1 and the lateral talus top 3 are temporarily fixed to the joint using absorbable calcium phosphate bone cement. The combination of the separate lateral tibial tray 1, intermediate pad 2, and lateral talus top 3 supports implantation through a minimally invasive 3-4cm incision, reducing osteotomy by 30%, thus improving surgical convenience and safety. The rough surface increases the contact area between the bone and the lateral talus top 3 and enhances the mechanical locking effect, accelerating osseointegration. The sagittal relationship between one side of the lateral talus top 3 and the concave surface 201 further improves the integration speed. The angled sliding connection simulates the gradual rolling and sliding mechanism of a natural ankle joint, reducing stress concentration at the joint surface edge, lowering peak stress by 30%, and significantly extending the life of the polyethylene liner. The cooperation between the connecting groove 4 and the connecting strip 5 provides rapid intraoperative positioning, reducing surgical time, while allowing non-destructive adjustments during the operation. It can replace the intermediate liner 2 of different thicknesses during the operation. During the connection process, when the connecting strip 5 is embedded in the connecting groove 4 and locked by the buckle, the No. 1 shape memory polymer 402 is activated, and it expands at 37°C to fill the gap between the connecting strip 5 and the connecting groove 4 to form a rigid connection.

[0055] A connecting assembly 6 is provided in the middle of the lateral tibial tray 1. The connecting assembly 6 includes a connecting groove 601, a top rod 602, a top block 603, an inclined block 604, and a fixing hole 605. The connecting groove 601 communicates with the connecting grooves 4 on both sides, and the top rods 602 are slidably connected to the inner walls of both sides of the connecting groove 601. The ends of the two sets of top rods 602 that are far apart are connected to the top blocks 603, and the ends of the two sets of top rods 602 that are opposite each other are connected to the inclined blocks 604. The two sets of inclined blocks 604 abut against each other. A fixing hole 605 is provided on one outer wall of the top block 603. A threaded groove 7 is provided in the middle of the two sets of connecting grooves 4. The end of the threaded groove 7 is connected to... The connecting grooves 601 are interconnected, and the connecting components 6 can connect and fix the connecting grooves 4 on the surface of the lateral tibial tray 1 and the connecting strips 5 at the bottom of the intermediate pad 2. When the connecting strips 5 are embedded in the connecting grooves 4, both sets of top blocks 603 match the slots 9 on both sides. By screwing the fastening bolts 8 into the threaded grooves 7, the fastening bolts 8 are screwed inward and at the same time, the ends of the fastening bolts 8 press against the inclined blocks 604 on both sides, thereby driving the inclined blocks 604 on both sides to move in a translational motion along the connecting grooves 601 toward the top rod 602. The inner wall of the middle of the threaded groove 7 is threaded with fastening bolts 8, and the outer wall of one side of both sets of connecting strips 5 is provided with slots 9. Block 603 matches the slots 9 on both sides. A second shape memory polymer 901 is embedded in the inner wall of one side of each slot 9. The second shape memory polymer 901 matches the fixing hole 605. The inclined block 604 moves, pushing the top rod 602 in a synchronous translational motion. The top rod 602 moves, causing the top block 603 to move out of the connecting groove 601 and then embed into the slot 9 to engage and fix the connecting strip 5, thus achieving a fixed connection between the lateral tibial tray 1 and the intermediate pad 2. Simultaneously, after connection, the first shape memory polymer 402 expands at 37°C to fill the gap between the connecting strip 5 and the connecting groove 4, forming a rigid connection, thereby improving the stability of the connection. Meanwhile, the second... The shape memory polymer 901 expands at 37°C to fill the fixing hole 605, thus fixing and limiting the top block 603. The top block 603, in conjunction with the first shape memory polymer 402, achieves a double stable connection between the connecting strip 5 and the connecting groove 4, preventing the connection from loosening under long-term wear. At the same time, the second shape memory polymer 901 expands at 37°C to fill the fixing hole 605, thus fixing and limiting the top block 603 after connection, preventing the bolts from loosening and causing the top block 603 to separate from the groove 9. This improves the stability of the connection between the opposite tibial tray 1 and the intermediate pad 2, and even if the bolts loosen, it will not affect its rigid connection.

[0056] Each of the four ends of the lateral talus top 3 is provided with an oblique locking screw hole 10. The oblique locking screw hole 10 is threaded inside, and the screw hole direction is at a 40° angle to the horizontal plane. The rough surface of the lateral talus top 3 is generated by laser cladding technology to form a gradient porous titanium structure, with the porosity gradually changing from 80% to 30% from the surface to the inside, and the pore diameter 50-500μm. The design of the screw hole direction at a 40° angle to the horizontal plane conforms to the shear force transmission direction when the ankle joint is under force, which can effectively disperse the stress at the bone-screw interface and reduce screw loosening or breakage caused by stress concentration. Risks: The high porosity of the surface layer (80%) promotes rapid osteoblast ingrowth, with a bone ingrowth rate of >50% 6 weeks post-surgery. The internal porosity decreases to 30%, matching the elastic modulus transition from cancellous bone to cortical bone (1-15 GPa), avoiding stress-induced bone resorption. The pore size is graded as follows: large pores (300-500 μm) facilitate vascularization and bone tissue ingrowth, while small pores (50-200 μm) enhance mechanical strength. The porous structure and matrix are integrated by layer-by-layer cladding of titanium alloy powder with a high-energy laser beam, avoiding the risk of coating peeling.

[0057] A piezoelectric sensor 11 is embedded in the center of the intermediate pad 2, and an RFID sensor 12 is provided on one side of the piezoelectric sensor 11. The outer walls of both the piezoelectric sensor 11 and the RFID sensor 12 are covered with silicone pads 13.

[0058] The silicone pad 13 is made of medical-grade silicone. The surface of the piezoelectric sensor 11 and the RFID sensor 12 is covered with the silicone pad 13 to ensure biocompatibility and compatibility with human tissue. The sensor is activated by radio frequency energy emitted by an external reader, eliminating the need for a built-in battery and avoiding the risk of internal power supply. The piezoelectric sensor 11 converts the pressure signal into an electric charge signal, which is then stored or transmitted after analog-to-digital conversion by the RFID chip. The RFID sensor 12 is model ST25TV02KC, which integrates a piezoresistive sensor to monitor the thickness change of the intermediate pad 2 and monitor the pad wear rate in real time. If the wear rate exceeds the threshold, it prompts the doctor to adjust the rehabilitation plan or intervene in advance.

[0059] The intermediate pad 2 is made of vitamin E-doped highly cross-linked polyethylene, and the lateral tibial tray 1 and the lateral talus top 3 are both made of titanium alloy.

[0060] Vitamin E doping significantly reduces the inflammatory response of wear particles, decreases macrophage activation rate by 40%, and inhibits periprosthetic bone resorption. Titanium alloy provides rigid support, while polyethylene absorbs impact loads. The elastic modulus gradient of the two materials is matched to achieve physiological stress transfer.

[0061] The tibial tray 1 has a mounting connection hole 14 at its center. The four ends of the outer wall of the tibial tray 1 away from the middle pad 2 are provided with positioning posts 15. The outer wall of the tibial tray 1 near the positioning posts 15 is provided with micro-holes 16.

[0062] Magnesium alloy biodegradable screws can be spirally installed through the mounting connection hole 14 to connect and fix it to the tibial joint. The positioning post 15 plays a positioning role to prevent displacement during installation. After bone tissue grows into the micro hole 16, it forms an anchoring structure, which improves shear strength and significantly reduces the risk of loosening.

[0063] Both the first shape memory polymer 402 and the second shape memory polymer 901 are made of polyurethane-based shape memory polymers. By adjusting the ratio of hard segments and soft segments, the glass transition temperature is precisely set to 36-37℃.

[0064] After implantation, the shape memory polymer No. 1 402 and the shape memory polymer No. 2 901 are induced by body temperature to expand the SMP, fill the 0.2mm micro-motion gap, and increase the interfacial shear strength from 5MPa in the temporary state to 20MPa, thereby improving the stability of the connection and preventing loosening.

[0065] The bone contact surfaces of the lateral tibial tray 1 and the lateral talus top 3 are both coated with a gradient bioactive coating 17, which, from the inside out, consists of:

[0066] Inner layer: Hydroxyapatite, 80wt%, balance is titanium alloy substrate material, thickness 50μm;

[0067] Intermediate layer: Strontium-doped hydroxyapatite, 50 wt%, with the remainder being titanium alloy substrate material, 30 μm thick;

[0068] Outer layer: Mesoporous silica nanoparticle layer containing bone morphogenetic protein-2, 20 μm thick.

[0069] The outer layer of bone morphogenetic protein-2 (BMP-2) induces osteoprogenitor cell aggregation and callus formation, the middle layer is doped with strontium hydroxyapatite (Sr-HA) to promote mineralization, and the inner layer of hydroxyapatite (HA) guides osteogenic formation, achieving complete integration of the bone interface and mechanical strength at physiological levels. The gradient coating, through a three-in-one design of bone induction, osteoconduction, and bone metabolism regulation, precisely regulates the bone regeneration process at different stages after surgery, while solving core clinical problems such as infection, loosening, and stress shielding, thus improving the bone integration efficiency and long-term stability of the ankle joint prosthesis.

[0070] The working process of the technical solution provided by this invention is as follows:

[0071] In use, this invention involves first making a 3cm minimally invasive incision during surgery, then removing the diseased cartilage under precise positioning. A lateral tibial tray 1 is implanted into one tibial joint, and a lateral talus top 3 is implanted into one talus joint. These are temporarily fixed with bone cement. A magnesium alloy biodegradable screw is then screwed into the oblique locking screw hole 10 and the installation connection hole 14 to connect and fix them. A sample pad is installed on top of the lateral tibial tray 1, and different angles are adjusted to determine the size of the intermediate pad 2. The sample pad is then removed, and the intermediate pad 2 is installed. After the connecting strip 5 is embedded in the connecting groove 4, both sets of top blocks 603 match the two side slots 9. The screw is then screwed into the threaded groove 7. As the bolts are screwed inward to secure the connection, their ends compress the inclined blocks 604 on both sides, causing them to move along the connecting groove 601 towards the top rod 602. The movement of the inclined blocks 604 pushes the top rod 602 to move synchronously. The movement of the top rod 602 causes the top block 603 to move out of the connecting groove 601 and into the slot 9, thus engaging and fixing the connecting strip 5. This achieves a fixed connection between the lateral tibial tray 1 and the intermediate pad 2. Simultaneously, after connection, the No. 1 shape memory polymer 402 expands at 37°C to fill the gap between the connecting strip 5 and the connecting groove 4, forming a rigid connection and improving the stability of the connection. Meanwhile, the No. 2 shape memory polymer 901 expands at 37°C to fill the fixing hole 605, thus fixing and limiting the top block 603. The top block 603, in conjunction with the No. 1 shape memory polymer 402, achieves a double, stable connection between the connecting strip 5 and the connecting groove 4, preventing loosening under long-term wear. Simultaneously, the expansion of the No. 2 shape memory polymer 901 at 37°C fills the fixing hole 605, fixing and limiting the top block 603 after connection, preventing bolt loosening and separation of the top block 603 from the groove 9. This improves the stability of the connection between the opposite tibial tray 1 and the intermediate pad 2, even when facing screws. Even if the plug loosens, it will not affect its rigid connection. Body temperature triggers the expansion of SMP, thereby achieving a stable fixation effect for the installation. The outer layer of bone morphogenetic protein-2 (BMP-2) induces osteoprogenitor cell aggregation and callus formation. The middle layer is doped with strontium hydroxyapatite (Sr-HA) to promote mineralization, and the inner layer of hydroxyapatite (HA) guides osteogenic formation, achieving complete integration of the bone interface. The mechanical strength reaches the physiological level. The gradient coating is designed with a three-in-one approach of bone induction, bone conduction and bone metabolism regulation, which precisely regulates the bone regeneration process at different stages after surgery. At the same time, it solves the core clinical problems of infection, loosening and stress shielding, and improves the bone integration efficiency and long-term stability of the ankle joint prosthesis.

[0072] This invention encompasses any substitutions, modifications, equivalent methods, and solutions made within the spirit and scope of this invention. To provide the public with a thorough understanding of this invention, specific details are described in detail in the following preferred embodiments; however, those skilled in the art will fully understand the invention even without these details. Furthermore, to avoid unnecessary misunderstanding of the essence of this invention, well-known methods, processes, procedures, components, and circuits are not described in detail.

[0073] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A single ankle joint clinical surgical surface replacement system, comprising a lateral tibial tray, an intermediate pad, and a lateral talus top; characterized in that, The top of the lateral tibial tray is provided with an intermediate pad, and the side of the intermediate pad away from the lateral tibial tray is provided with a lateral talus top. The outer wall of the intermediate pad near the top of the lateral talus is concave, and the side of the top of the lateral talus near the intermediate pad is slidably connected to the concave surface. The side of the top of the lateral talus near the intermediate pad is a smooth surface, and the side of the top of the lateral talus away from the intermediate pad is a rough surface. It also includes connecting grooves on both sides of the surface of the tibial tray, with connecting strips arranged and connected at one end of the middle pad near the tibial tray. The connecting strips match the connecting grooves and are embedded in the connecting grooves. Limiting grooves are arranged at the inner edge of the connecting grooves, and a No. 1 shape memory polymer is embedded inside the limiting grooves. A connecting assembly is provided in the middle of the lateral tibial tray. The connecting assembly includes a connecting groove, a top rod, a top block, an inclined block, and a fixing hole. The connecting groove is connected to the connecting grooves on both sides, and the inner walls on both sides of the connecting groove are slidably connected to the top rod. The ends of the two sets of top rods that are far apart are connected to the top block, and the ends of the two sets of top rods that are opposite each other are connected to the inclined block. The two sets of inclined blocks abut against each other, and a fixing hole is provided on one outer wall of the top block. The four ends of the lateral talus bone top are provided with oblique locking screw holes. The oblique locking screw holes are threaded inside. The direction of the screw holes is at a 40° angle to the horizontal plane. The rough surface of the lateral talus bone top is generated by laser cladding technology to form a gradient porous titanium structure. The porosity gradually changes from 80% to 30% from the surface to the inside, and the pore size is 50-500μm. A piezoelectric sensor is embedded in the center of the intermediate pad, and an RFID sensor is provided on one side of the piezoelectric sensor. Both the piezoelectric sensor and the RFID sensor are covered with silicone pads on their outer walls.

2. The single ankle joint clinical surgical surface replacement system according to claim 1, characterized in that, The two sets of connecting grooves are provided with threaded grooves in the middle, the ends of the threaded grooves are connected to the connecting grooves, and the inner wall of the middle of the threaded grooves is threaded with fastening bolts.

3. The single ankle joint clinical surgical surface replacement system according to claim 1, characterized in that, Both sets of connecting strips have a slot on one side of their outer wall, and both sets of top blocks match the slots on both sides. A second shape memory polymer is embedded in one side of the slot, and the second shape memory polymer matches the fixing hole.

4. The single ankle joint clinical surgical surface replacement system according to claim 1, characterized in that, The intermediate liner is made of vitamin E-doped highly cross-linked polyethylene, and the lateral tibial tray and the lateral talus top are both made of titanium alloy.

5. The single ankle joint clinical surgical surface replacement system according to claim 4, characterized in that, The tibial tray has a mounting connection hole at its center. The outer wall of the tibial tray away from the middle pad has positioning posts at all four ends. The outer wall of the tibial tray near the positioning posts has micro-holes arranged in a row.

6. The single ankle joint clinical surgical surface replacement system according to claim 3, characterized in that, Both the No. 1 and No. 2 shape memory polymers are made of polyurethane-based shape memory polymers.

7. The single ankle joint clinical surgical surface replacement system according to claim 5, characterized in that, The bone contact surfaces of the lateral tibial tray and the lateral talus top are coated with a gradient bioactive coating, which, from the inside out, consists of: Inner layer: Hydroxyapatite, 80wt%, balance is titanium alloy substrate material, thickness 50μm; Intermediate layer: strontium-doped hydroxyapatite, 50 wt%, balance is titanium alloy substrate material, 30 μm thick; Outer layer: Mesoporous silica nanoparticle layer containing bone morphogenetic protein-2, 20 μm thick.

Images