Unicompartmental knee prosthesis

Abstract

The present invention provides a single-compartment knee joint prosthesis, belonging to the field of medical device technology. It includes a femoral component, a pair of ridge nail components are connected to the inner wall of the femoral component; it also includes a tibial polyethylene gasket, the bottom of the tibial polyethylene gasket is connected to the tibial component, the tibial component includes a tibial metal tray clamped with the tibial polyethylene gasket, a keel is fixedly connected in the middle of the bottom of the tibial metal tray, and a pair of tibial side bone nails are fixedly connected to one side of the bottom of the tibial metal tray. The present invention increases the stability of the prosthesis by setting movable parts, and adapts to more patients by controlling the extension degree of the side edges according to the different bone qualities of the patients. The operation is convenient, and the single-radius prosthesis and the protective layer are set to avoid the prosthesis falling off due to the smooth curved surface of the side of the prosthesis, which affects the surgical efficiency. At the same time, the claw groove and the buckle clamping of the protective layer make the nail groove sealed to prevent the knee effusion from flowing into and solidifying, which increases the difficulty of later disassembly and replacement.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a single-compartment knee joint prosthesis. Background Art

[0002] Unicompartmental knee prosthesis is a prosthesis used in artificial knee replacement surgery. It is used to treat pain, dysfunction and joint movement restriction caused by severe lesions or injuries of the knee joint. Compared with total knee replacement surgery, unicompartmental knee prosthesis pays more attention to the repair of local lesions and only replaces the damaged area on the inside or outside of the knee joint. With the aging of the population, unicompartmental knee replacement surgery is growing rapidly. This is a minimally invasive surgical method with good therapeutic effects. The fixation methods of unicompartmental knee prosthesis are divided into bone cement type, biological type and hybrid type.

[0003] In actual use, the biological unicompartmental knee joint components currently used clinically are first cut out of the femur and tibia to form a plane suitable for prosthesis installation, and mounting holes that are adapted to the screws on the prosthesis component are opened on the plane. The edge of the prosthesis component is then installed by grabbing it with a mechanical claw. For the firmness of the installation, the screws and the mounting holes are usually interference fit. However, due to the different bone quality of each person, the bearing capacity of the tibia and femur is also different. When the patient's bone condition is poor or osteoporosis occurs, bone fractures or collapse may occur, and the prosthesis needs to be removed again with a mechanical claw. Due to the interference fit, a large force needs to be used, which is easy to cause secondary damage to the femur and tibia. In addition, leg length inconsistency, muscle strength imbalance and bone deformity can lead to uneven force distribution in the knee, in which excessive force is borne in some parts of the prosthesis, causing the knee prosthesis to loosen and dislocate. Therefore, the present application provides a unicompartmental knee joint prosthesis to meet the needs. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a unicompartmental knee joint prosthesis to solve the problems of the existing prosthesis being easy to be pulled out, being unable to be adaptively adjusted, and having hidden dangers in clamping during installation.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] A single-compartment knee prosthesis includes a femoral component, a pair of rib nail assemblies are connected to the inner wall of the femoral component; it also includes a tibial polyethylene gasket, the bottom of the tibial polyethylene gasket is connected to the tibial component, the tibial component includes a tibial metal tray clamped with the tibial polyethylene gasket, a keel is fixedly connected to the middle of the bottom of the tibial metal tray, and a pair of tibial side bone nails are fixedly connected to one side of the bottom of the tibial metal tray; the rib nail assembly is used to increase the anti-rotation and anti-pullout capabilities of the device itself and to adjust during surgery to avoid secondary trauma caused by interference fit.

[0007] Preferably, the femoral component comprises a single radius prosthesis, a pair of nail grooves are provided on the surface of the single radius prosthesis, a plurality of claw grooves are provided on the inner side wall of the nail groove, guide grooves are provided on both sides of the claw groove, and a guide groove is provided on the top of the claw groove.

[0008] Preferably, the outer side wall of the single-radius prosthesis is clamped with a protective layer, and the inner side wall of the single-radius prosthesis is provided with porous titanium metal trabeculae.

[0009] Preferably, the rib nail assembly includes a cone nail body fixedly connected to the inner wall of the nail groove, a screw component is connected to the top of the cone nail body, a movable component is connected to the outer wall of the screw component, and grooves are respectively provided inside the cone nail body to match the screw component and the movable component.

[0010] Preferably, the screw component includes a screw body rotatably connected to the top of the cone nail body, a first rotation groove is opened at the top of the thread of the screw body, a second rotation groove is opened at the bottom of the thread of the screw body, and a protrusion is provided on the cone nail body to adapt to the first rotation groove and the second rotation groove respectively.

[0011] Preferably, the movable component comprises a movable ring rotatably connected to the screw body, and four rotation grooves with equal distances are formed on an outer side wall of the movable ring, and a connecting rod is rotatably connected in the rotation groove.

[0012] Preferably, the other end of the connecting rod is rotatably connected to a linkage block, a pair of round protrusions are provided on both sides of the linkage block, a groove is provided on the cone nail body to match the round protrusions, and a movable rod is rotatably connected to the bottom of the linkage block.

[0013] Preferably, the other end of the movable rod is slidably connected with a side edge, the top of the side edge is provided with a groove adapted to the movable rod, the bottom of the side edge is provided with a rotating rod rotatably connected to the cone nail body, and the cone nail body is provided with a groove adapted to the rotating rod.

[0014] Compared with the prior art, the present invention has at least the following beneficial effects:

[0015] In the above scheme, movable parts are provided to adapt to more patients. According to the different bone conditions of the patients, the lateral edges are extended to increase the contact between the screws and the openings, thereby increasing the stability and pull-out resistance of the prosthesis. When a bone fracture occurs, the lateral edges are retracted to eliminate interference fit and avoid secondary injuries. The operation is convenient and the surgical efficiency of medical staff is further improved.

[0016] By providing a single-radius prosthesis and a protective layer, a mechanical claw is used to install the prosthesis during surgery through the claw groove in the nail groove, thereby avoiding the prosthesis from falling off due to the smooth curved surface of the side of the prosthesis, which affects the efficiency of the operation. At the same time, the clip connection between the claw groove and the protective layer makes the nail groove sealed to prevent knee effusion from flowing into and solidifying, which increases the difficulty of later disassembly and replacement. It also makes the contact surface between the femoral component and the tibial component smoother, reduces wear, increases the survival rate of the prosthesis, and improves the use effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated herein and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, further serve to explain the principles of the invention and to enable those skilled in the relevant art to make and use the invention.

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of a unicompartmental knee prosthesis;

[0019] Figure 2 is a schematic diagram of the three-dimensional structure of the femoral component;

[0020] Figure 3 It is a schematic diagram of the three-dimensional structure of the femoral component;

[0021] Figure 4 A schematic diagram of the three-dimensional structure of the movable parts;

[0022] Figure 5 for Figure 4 Enlarged view of point A in the middle.

[0023] [reference numerals]

[0024] 1. Femoral component; 11. Single radius prosthesis; 12. Protective layer; 13. Porous titanium trabeculae; 14. Nail groove; 15. Guide groove; 16. Claw groove; 17. Guide groove; 2. Edge nail component; 21. Cone nail body; 22. Screw component; 221. Screw body; 222. First rotation groove; 223. Second rotation groove; 23. Movable component; 231. Movable ring; 232. Rotation groove; 233. Connecting rod; 234. Linkage block; 235. Round protrusion; 236. Movable rod; 237. Side edge; 238. Rotation rod; 3. Tibial polyethylene gasket; 4. Tibial component; 41. Tibial metal tray; 42. Keel; 43. Tibial side bone nail.

[0025] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments, and the adjustments or modifications made are still included in the scope of the attached claims. DETAILED DESCRIPTION

[0026] The following is a detailed description of a unicompartmental knee prosthesis provided by the present invention in conjunction with the accompanying drawings and specific embodiments. It is also noted that, in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for a more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0027] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0028] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0029] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” not only means “directly on” something, but also includes the meaning of being “on” something with intervening features or layers therebetween, and “on” or “over” not only means “on” or “above” something, but also includes the meaning of being “on” or “above” something with no intervening features or layers therebetween.

[0030] Additionally, spatially relative terms such as "under," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as shown in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein may be similarly interpreted accordingly.

[0031] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a unicompartmental knee prosthesis, including a femoral component 1, a pair of rib nail assemblies 2 are connected to the inner wall of the femoral component 1; it also includes a tibial polyethylene gasket 3, the bottom of the tibial polyethylene gasket 3 is connected to a tibial component 4, the contact surface between the tibial component 4 and the tibia and the contact surface between the femoral component 1 and the femur are both provided with porous titanium metal trabeculae 13, the tibial component 4 includes a tibial metal tray 41 clamped with the tibial polyethylene gasket 3, a keel 42 is fixedly connected to the middle of the bottom of the tibial metal tray 41, and a pair of tibial side bone nails 43 are fixedly connected to one side of the bottom of the tibial metal tray 41; the rib nail assembly 2 is used to increase the anti-rotation and anti-pullout capabilities of the device itself to avoid displacement or loosening of the component in the critical early implantation period and to adjust during surgery to avoid secondary trauma caused by interference fit.

[0032] like Figure 2 As shown, the femoral component 1 includes a single-radius prosthesis 11, a pair of nail grooves 14 are provided on the surface of the single-radius prosthesis 11, and a plurality of claw grooves 16 are provided on the inner wall of the nail groove 14. The shape of the claw groove 16 is adapted to the shape of the installation claw. During installation, the claw is inserted into the nail groove 14 and expanded to extend to the claw groove 16 for limiting the position to avoid slipping and causing unnecessary mistakes. Guide grooves 17 are provided on both sides of the claw groove 16 to facilitate rapid positioning and fixing of the claw. A guide groove 15 is provided on the top of the claw groove 16. The outer wall of the single-radius prosthesis 11 is clamped with a protective layer 12, and the inner wall of the protective layer 12 is in contact with the outer wall of the single-radius prosthesis 11. The protective layer 12 is provided with a plurality of buckles on its surface to match the claw grooves 16. When installing the protective layer 12, the buckles are slid into the claw grooves 16 through the guide grooves 15 and are limited by the guide grooves 15, thereby increasing the anti-rotation capability of the device and increasing stability. The inner wall of the single-radius prosthesis 11 is provided with porous titanium trabeculae 13. The wire diameter of the titanium trabecular structure is 100um, the pore size of the trabecular structure is designed to be 300-600μm, and the porosity is 30%-60%. The above structural parameters better simulate the trabecular structure of the human body, have a bone-inducing effect, are easier for bone growth, and ensure the long-term use of the prosthetic component.

[0033] like Figure 3-Figure 5As shown, the rib nail assembly 2 includes a cone nail body 21 fixedly connected to the inner wall of the nail groove 14, the cone nail body 21 is designed as a bullet head, has a guiding function, and reduces the difficulty of installing the assembly, a screw component 22 is connected to the top of the cone nail body 21, and a movable component 23 is connected to the outer wall of the screw component 22. Grooves are respectively provided inside the cone nail body 21 to adapt to the screw component 22 and the movable component 23. The screw component 22 includes a screw body 221 rotatably connected to the top of the cone nail body 21, and a first rotation groove is provided at the top of the thread of the screw body 221 222, a second rotation groove 223 is provided at the bottom of the thread of the screw body 221, and a protrusion is provided on the cone nail body 21, which is respectively matched with the first rotation groove 222 and the second rotation groove 223. The advantage of such a setting is that by twisting the screw component 22, it rotates itself to drive the lower movable component 23 to move up and down, while the screw component itself does not move, so it is convenient to arbitrarily adjust the extension size of the movable component 23 without affecting the installation of the upper protective layer 12 due to the screw, thereby improving the rationality of the use of the knee joint prosthesis and increasing the surgical efficiency of medical staff.

[0034] like Figure 3-Figure 5 As shown, the movable component 23 includes a movable ring 231 rotatably connected to the screw body 221, and four rotation grooves 232 with the same distance are opened on the outer wall of the movable ring 231. A connecting rod 233 is rotatably connected in the rotation groove 232. When the screw body 221 is rotated, the movable ring 231 is driven to move up and down, and the connecting rod 233 rotatably connected thereto is pressed down to move. The other end of the connecting rod 233 is rotatably connected to a linkage block 234, and a pair of round protrusions 235 are provided on both sides of the linkage block 234. A groove is provided on the cone nail body 21 to adapt to the round protrusion 235. The linkage block 234 is driven by the connecting rod 233 to rotate with the round protrusion 235 and the center of the circle. The bottom of the linkage block 234 is rotatably connected to A movable rod 236 has a lateral edge 237 slidably connected to the other end of the movable rod 236. A groove is provided on the top of the lateral edge 237 to match the movable rod 236. A rotating rod 238 is provided at the bottom of the lateral edge 237 to be rotatably connected to the cone nail body 21. A groove is provided in the cone nail body 21 to match the rotating rod 238. The lateral edge 237 is pushed and squeezed outward with the rotating rod 238 as the center. The edge of the lateral edge 237 is a sharp blade, which is embedded in the femur for positioning and also plays an anti-rotation role. According to the different bone qualities of the patients, the extension degree of the lateral edge 237 can be controlled by twisting the screw body 221 to adapt to more patients. The operation is convenient and the surgical efficiency of medical staff is further improved.

[0035] The technical solution provided by the present invention is to set a screw component so that it rotates to drive the movable component below to move up and down, while the screw component itself does not move, so that the extension size of the movable component can be adjusted arbitrarily without affecting the installation of the upper protective layer due to the screw, thereby improving the rationality of the use of the knee joint prosthesis and increasing the surgical efficiency of medical staff.

[0036] By setting up movable parts to adapt to more patients, the side edges are extended to increase the contact between the screw and the opening according to the different bone conditions of the patients, thereby increasing the stability and pull-out resistance of the prosthesis. When encountering bone fractures, the side edges are retracted to eliminate interference fit and avoid secondary injuries. The operation is convenient and the surgical efficiency of medical staff is further improved.

[0037] By providing a single-radius prosthesis and a protective layer, a mechanical claw is used to install the prosthesis during surgery through the claw groove in the nail groove, thereby avoiding the prosthesis from falling off due to the smooth curved surface of the side of the prosthesis, which affects the efficiency of the operation. At the same time, the clip connection between the claw groove and the protective layer makes the nail groove sealed to prevent the inflow of knee effusion and solidification, which increases the difficulty of later disassembly and replacement. It also makes the contact surface between the femoral component and the tibial component smoother, reduces wear, increases the survival rate of the prosthesis, and improves the use effect.

[0038] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0039] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A unicompartmental knee prosthesis, characterized in that: include: A femoral component, wherein a pair of rib nail components are connected to the inner wall of the femoral component; It also includes a tibial polyethylene pad, the bottom of which is connected to a tibial component, the tibial component includes a tibial metal tray clamped with the tibial polyethylene pad, a keel is fixedly connected in the middle of the bottom of the tibial metal tray, and a pair of tibial side bone screws are fixedly connected to one side of the bottom of the tibial metal tray, and the tips of the tibial side bone screws are conical; The prism assembly is used to increase the anti-rotation and anti-pullout capabilities of the device itself and to adjust during surgery to avoid secondary trauma caused by interference fit; The femoral component comprises a single-radius prosthesis, a pair of nail grooves are formed on the surface of the single-radius prosthesis, a plurality of claw grooves are formed on the inner side wall of the nail groove, guide grooves are formed on both sides of the claw groove, and a guide groove is formed on the top of the claw groove; The rivet assembly comprises a cone rivet body fixedly connected to the inner side wall of the rivet groove, a screw component is connected to the top of the cone rivet body, a movable component is connected to the outer side wall of the screw component, and grooves are respectively provided inside the cone rivet body to match the screw component and the movable component; The screw component comprises a screw body rotatably connected to the top of the cone nail body, a first rotation groove is formed at the top of the thread of the screw body, a second rotation groove is formed at the bottom of the thread of the screw body, and a convex block is formed on the cone nail body to match the first rotation groove and the second rotation groove respectively; The movable component comprises a movable ring rotatably connected to the screw body, and the outer wall of the movable ring is provided with four rotation grooves with the same distance, and a connecting rod is rotatably connected in the rotation groove; The other end of the connecting rod is rotatably connected to a linkage block, a pair of round protrusions are provided on both sides of the linkage block, a groove is provided on the cone nail body to match the round protrusions, and a movable rod is rotatably connected to the bottom of the linkage block; The other end of the movable rod is slidably connected with a side edge, the top of the side edge is provided with a groove adapted to the movable rod, the bottom of the side edge is provided with a rotating rod rotatably connected to the cone nail body, and the cone nail body is provided with a groove adapted to the rotating rod.

2. The unicompartmental knee prosthesis according to claim 1, characterized in that: The outer side wall of the single-radius prosthesis is clamped with a protective layer, and the inner side wall of the single-radius prosthesis is provided with porous titanium metal trabeculae.

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