Knee joint prosthesis
Technical Field
The invention relates to the technical field of medical instruments, in particular to a knee joint prosthesis.
Background
The laser cladding technology brings qualitative changes to the processing technology of the medical appliance industry, which makes many impossible and makes many difficulties simple. In recent years, the laser cladding technology is rapidly developed, but still blank in the medical industry, and is believed to be applied to the medical instrument industry in the near future. The laser cladding technology can clad on substrates made of different materials, and the clad powder materials can be diversified, can be suitable for different parts of a human body, and is very strong in applicability.
The trabecular structure of human bone is the extension of cortical bone in cancellous bone, and is in irregular three-dimensional grid structure in the marrow cavity, and plays a role in supporting hematopoietic tissues. The trabecula of the human body is of an uneven grid structure at the same position, the structures at different positions are greatly different, the trabecula of the human body is of different structures at the same position under different body states, and the trabecula of the human body is divided into a tension trabecula and a pressure trabecula. The human natural bone trabecular structure is the result of human evolution and has profound biomechanical causes and cellular ingrowth causes.
The research surface shows that the high trabecular bone porosity and the connectivity can improve the bone generation level, the bone growth is most suitable when the aperture is 300-400 mu m, the bone growth is fastest when the aperture is 100-200 mu m, the gradient multi-level pores have positive effects on the differentiation of bone marrow stem cells and the regeneration of soft tissues, the rough porous surface can well induce the generation of ectopic bones, and the adhesion, proliferation and differentiation capacities of osteoblasts can be improved. According to the research surface, the internal fixation micro-motion range is less than 28 microns, so that the requirement of the biological fixation bone ingrowth can be met, and when the micro-motion range is more than 150 microns, a soft tissue membrane is generated on the interface between the prosthesis and the bone, so that the fixation effect is influenced. The surface roughness on the macroscopic scale can greatly reduce micromotion and is beneficial to bone ingrowth.
The knee joint prosthesis is a surgical implant for replacing the knee joint, is used for knee replacement surgery on the surface of the knee joint, and is a method for treating the damaged knee joint and replacing the damaged knee joint with an artificial knee joint. The existing knee joint prosthesis mainly comprises a femoral condyle prosthesis, a tibial pad prosthesis and a tibial tray prosthesis. The knee joint prosthesis in the center of the prior art is usually made of bone cement, and bone cement monomers may enter the lung of a human body through blood during and after operation, so that pulmonary embolism is caused, and the life safety of a patient is endangered; or cause high pressure in the bone marrow cavity during filling, causing fat to drip into human blood, causing fat embolism. In addition, the bone cement is an inert material, the prosthesis can be loosened due to long-term micromotion, and a large amount of heat can be released during polymerization of the bone cement monomer, so that surrounding tissues are damaged. The laser cladding technology can clad different powder materials on the solid surface part of the non-biological prosthesis, so that the non-biological prosthesis is converted into the biological prosthesis, and the adverse effect caused by the fact that the non-biological prosthesis depends on bone cement is solved.
Disclosure of Invention
The invention aims to provide a knee joint prosthesis to solve the technical problems in the prior art.
In order to achieve the purpose, the invention adopts the technical scheme that: a knee joint prosthesis comprising: the artificial femoral condyle comprises a femoral condyle prosthesis, a tibial plateau pad prosthesis and a tibial plateau support prosthesis which are sequentially connected, wherein a 3D printed coating I is arranged on the surface of a base body of the femoral condyle prosthesis, and a 3D printed coating II is arranged on the surface of the base body of the tibial plateau support prosthesis; the surface of the base body of the femoral ankle prosthesis is provided with a first concave area, and the surface of the base body of the tibial plateau support prosthesis is provided with a second concave area; the first coating comprises a first inner coating and a first outer coating, the first inner coating is arranged in the first recessed area, the thickness of the first inner coating is equal to the depth of the first recessed area, the first outer coating is arranged on the surface of the first inner coating, and the first outer coating is of a sawtooth structure; the second coating comprises a second inner coating and a second outer coating, the second inner coating is arranged in the second concave area, the thickness of the second inner coating is equal to the depth of the second concave area, the second outer coating is arranged on the surface of the second inner coating, and the second outer coating is of a sawtooth-shaped structure.
In an optional embodiment, the inner coating I and the inner coating II are bone trabecula structures, the grid porosity of the bone trabecula structures is 50% -80%, the pore diameter is set to be 100-400 mu m, and the thickness is 0.5-1 mm.
In an optional embodiment, the first outer coating and the second outer coating are bone trabecula structures, saw teeth of the saw-toothed structures are different in length and are unevenly distributed on the surfaces of the first inner coating and the second inner coating, the length of each saw tooth is 0.5-1mm, and included angles between each saw tooth and the surfaces of the first inner coating and the second inner coating are respectively 30-90 degrees.
In an alternative embodiment, the depth of the first concave area and the second concave area is 0.5-1 mm.
In an alternative embodiment, the thickness of the first inner coating and the second inner coating is 0.5-1 mm.
In an alternative embodiment, the coating layer is arranged on the inner surface of the femoral ankle prosthesis, and the inner surface of the femoral ankle prosthesis is an arc surface adapted to the human body.
In an alternative embodiment, the second coating is disposed on the lower surface of the tibial plateau prosthesis and the elongated stem surface of the tibial plateau prosthesis.
In an alternative embodiment, the base of the femoral condyle prosthesis, the tibial plateau pad prosthesis, and the tibial plateau tray prosthesis is a titanium alloy produced by a forging process.
The invention has the beneficial effects that:
(1) the 3D printed bone trabecular structure in the knee joint prosthesis is different from the traditional bone trabecular structure, and is more beneficial to the growth of bones and the medium-and-long-term stability of the prosthesis. 3D prints bone trabecula structure and divide into two-layerly, and the inlayer is net bone trabecula structure, remains original advantage, and outer zigzag structure increases area of contact, improves frictional force, prevents the false body slippage, does benefit to and improves the stability of false body implantation early stage.
(2) The base body in the knee joint prosthesis is machined by forging titanium alloy, so that the fatigue strength is high, and all adverse effects caused by the fact that non-biological prostheses depend on bone cement are avoided.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a schematic overall structural diagram of a knee joint prosthesis according to an embodiment of the present invention.
Fig. 2 is a structural diagram of a 3D printed coating on the surface of a femoral condyle prosthesis according to an embodiment of the present invention.
Fig. 3 is a schematic structural view of a tibial plateau tray prosthesis according to an embodiment of the present invention.
Fig. 4 is a schematic top view of a tibial plateau tray prosthesis according to an embodiment of the present invention.
Wherein, the reference numbers in the figures are: 1. femoral condyle prosthesis, 2 tibial plateau pad prosthesis, 3 tibial plateau support prosthesis, 4 coating one, 5 coating two, 6, depressed area one, 7, inner coating one, 8, outer coating one, 9, depressed area two, 10, inner coating two, 11, outer coating two, 12, femoral condyle inner surface, 13 tibial plateau support lower surface, 14 tibial plateau support extension handle.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly or indirectly secured to the other element. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element. The terms "upper", "lower", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positions based on the orientations or positions shown in the drawings, and are for convenience of description only and not to be construed as limiting the technical solution. The terms "first", "second" and "first" are used merely for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "plurality" is two or more unless specifically limited otherwise.
Referring to fig. 1-2, the present embodiment provides a knee joint prosthesis, including: the base bodies of the femur ankle prosthesis 1, the tibia platform pad prosthesis 2 and the tibia platform support prosthesis 3 are titanium alloy produced by adopting a forging process, and the base bodies have the advantages of being close to human bones in density, light in weight, low in elastic modulus, high in mechanical strength, high in fatigue resistance and corrosion resistance and the like.
Specifically, the surface of the base body of the femoral ankle prosthesis 1 is provided with a first 3D printed coating 4, the first coating 4 is arranged on the inner surface 12 of the femoral ankle prosthesis 1, and the inner surface 12 of the femoral ankle prosthesis 1 is an arc-shaped surface adaptive to the human body. It is to be noted that, in this case, the coating layer one 4 includes an inner coating layer one 7 and an outer coating layer one 8, the inner coating layer one 7 is provided in the depressed area one 6, and the thickness of the inner coating layer one 7 is equal to the depth of the depressed area one 6, and preferably, the depth of the depressed area one 6 and the thickness of the inner coating layer one 7 are each 0.5 to 1 mm.
The first inner coating 7 is of a trabecular bone structure, the grid porosity of the trabecular bone structure is 50% -80%, the pore diameter is set to be 100-400 mu m, the thickness is 0.5-1mm, the thickness of a 3D printed trabecular bone region on the surface is proper, the adhesion is strong, bone ingrowth is facilitated, the coating strength is better, and the prosthesis is beneficial to medium-term and long-term stability.
In this embodiment, the first external coating 8 is arranged on the surface of the first internal coating 7, the first external coating 8 is of a saw-toothed structure, the first external coating 8 is of a trabecular bone structure, saw teeth of the saw-toothed structure are different in length and are unevenly distributed on the surface of the first internal coating 7, the length of each saw tooth is 0.5-1mm, the included angle degrees between each saw tooth and the surface of the first internal coating 7 are respectively 30-90 degrees, and the saw-toothed trabecular bone structure with the inclination angle is beneficial to smooth implantation of the femoral ankle prosthesis 1 and prevents the femoral ankle prosthesis 1 from falling out.
It is worth mentioning that the trabecular bone structure in the femoral condyle prosthesis 1 can increase the contact area between the surface of the prosthesis and the surface of the human bone, increase the friction force, prevent the femoral condyle prosthesis 1 from slipping, and realize good biological fixation.
Referring to fig. 3-4, specifically, a second coating 5 printed in 3D is disposed on the surface of the base of the tibial plateau tray prosthesis 3, and the second coating 5 is disposed on the lower surface 13 of the tibial plateau tray prosthesis 3 and the surface of the elongate stem 14 of the tibial plateau tray prosthesis 13. It should be noted that, the second coating 5 includes a second inner coating 10 and a second outer coating 11, the second inner coating 10 is disposed in the second recessed area 9, the thickness of the second inner coating 10 is equal to the depth of the second recessed area 9, and preferably, the depth of the second recessed area 9 and the thickness of the second inner coating 10 are both 0.5-1 mm.
The second inner coating 10 is of a trabecular bone structure, the porosity of a grid of the trabecular bone structure is 50% -80%, the pore diameter is set to be 100-400 mu m, the thickness is 0.5-1mm, the thickness of a 3D printed trabecular bone area on the surface is proper, the adhesion is strong, bone ingrowth is facilitated, the strength of the coating is better, and the stability of the prosthesis in a medium-term and a long-term mode is facilitated.
In this embodiment, the second outer coating 11 is disposed on the surface of the second inner coating 10, the second outer coating 11 is of a saw-toothed structure, the second outer coating 11 is of a trabecular bone structure, saw teeth of the saw-toothed structure are different in length and are unevenly distributed on the surface of the second inner coating 10, the length of each saw tooth is 0.5-1mm, the included angles between each saw tooth and the surface of the second inner coating 10 are respectively 30-90 degrees, and the saw-toothed trabecular bone structure with the inclination angle is beneficial to smooth implantation of the tibial plateau prosthesis 3 and prevention of the tibial plateau prosthesis 3 from coming off.
It is worth mentioning that the trabecular bone structure in the tibial plateau support prosthesis 3 can increase the contact area between the surface of the prosthesis and the surface of the human bone, increase the friction force, prevent the femoral tibial plateau support prosthesis 3 from slipping, and realize good biological fixation.
The 3D printing technology in the embodiment is preferably a laser cladding technology, and different powder materials can be clad on the solid surface part of the non-biological prosthesis through the laser cladding technology, so that the non-biological prosthesis is converted into the biological prosthesis, and the adverse effect caused by the fact that the non-biological prosthesis depends on bone cement is solved.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.