CN107280823B

CN107280823B - Patella Prosthesis and Artificial Knee Joint

Info

Publication number: CN107280823B
Application number: CN201710652146.8A
Authority: CN
Inventors: 贾海涛
Original assignee: Beijing Ansong Technology Co ltd
Current assignee: Beijing Ansong Technology Co ltd
Priority date: 2017-08-02
Filing date: 2017-08-02
Publication date: 2023-09-05
Anticipated expiration: 2037-08-02
Also published as: CN107280823A

Abstract

The application relates to the technical field of medical instruments, in particular to a patella prosthesis and an artificial knee joint. The patella prosthesis comprises a prosthesis main body, a rotator and a patella fixing piece; the prosthesis body has corresponding first and second faces; the first surface is provided with a main body groove which is matched and connected with the rotator, and the second surface is connected with the patella fixing piece; the body groove is capable of preventing the rotor from being separated from the prosthesis body; the rotor protrudes from the first surface, and the rotor can rotate around the axis of the rotor. The artificial knee joint comprises the patella prosthesis. The application aims to provide a patella prosthesis and an artificial knee joint, which are used for solving the technical problem of serious abrasion of the patella prosthesis in the prior art.

Description

Patella prosthesis and artificial knee joint

Technical Field

The application relates to the technical field of medical instruments, in particular to a patella prosthesis and an artificial knee joint.

Background

The artificial knee joint prosthesis is implanted into a human body after knee joint replacement operation, and has the function of recovering normal physiological functions of the human body. Replacement of the severely degenerated patella has been accepted, and the main stream knee prosthesis design in the market has fully considered the matching of the patellofemoral prosthesis, with long and wide trochlear grooves provided in front of the femoral prosthesis. With the great number of applications of patella replacement surgery, the design of patella prostheses is an important factor affecting the effectiveness of artificial knee joint replacement surgery.

Currently, the design of patella prostheses is generally in the form of integral or assembled fixation, and such patella prostheses each have an arcuate top portion that is fixed to the patella by means of bone cement or a biological coating. The traditional patella prosthesis is designed in such a way that the friction pair formed by the patella prosthesis and the femoral condyle prosthesis is always in a sliding friction state in the knee joint bending and stretching movement process, the contact position is concentrated on a fixed area, and serious abrasion occurs in the area along with the time, so that the service life of the whole knee joint prosthesis is directly influenced.

In order to extend the useful life of the knee prosthesis and minimize wear of the patellar prosthesis, it is necessary to maintain the friction pair formed by the patellar prosthesis and the femoral condyle prosthesis in a reasonable friction state for a long period of time.

Accordingly, the present application addresses the above-described problems by providing a new patella prosthesis and artificial knee joint that reduces wear of the patella prosthesis.

Disclosure of Invention

The application aims to provide a patella prosthesis to solve the technical problem of serious abrasion of the patella prosthesis in the prior art.

The application also aims to provide the artificial knee joint so as to solve the technical problem of serious abrasion of the patella prosthesis in the prior art.

Based on the first object, the patella prosthesis provided by the application comprises a prosthesis main body, a rotator and a patella fixing piece;

the prosthesis body has corresponding first and second faces; the first surface is provided with a main body groove which is matched and connected with the rotator, and the second surface is connected with the patella fixing piece;

the body groove is capable of preventing the rotor from being separated from the prosthesis body; the rotor protrudes from the first surface, and the rotor can rotate around the axis of the rotor.

Further, the prosthesis body includes a cap and a patella bearing; the top cover is fixedly connected with the patella support;

the first surface is a surface of the top cover far away from the patella support, and the second surface is a surface of the patella support far away from the top cover;

the top cover is provided with the main body groove, and the rotator is connected with the patella support.

Further, the rotator is connected with the patella support through a rolling body; the rotator and/or the patella support are provided with rolling grooves matched with the rolling bodies;

or the rotator is connected with the patella support through a bearing.

Further, the range of the surface roughness Ra of the surface of the rotator close to the patella support, the surface of the patella support close to the rotator, the outer circumferential surface of the rotator matched with the top cover, and the inner circumferential surface of the top cover matched with the rotator is as follows: ra is less than or equal to 1.5 mu m.

Further, the rotator and the top cover are connected in a conical surface fit manner; the cone angle A of the conical surface is in the range of: a is more than or equal to 5 degrees and less than or equal to 45 degrees.

Further, the first surface is a spherical crown or an ellipsoidal spherical crown; the rotating body is in smooth transition connection with the first surface;

the radius of the spherical crown is 15mm-45mm, the long radius of the ellipsoidal crown is 25mm-45mm, and the short radius of the ellipsoidal crown is 15mm-35mm.

Further, the number of patella fasteners is a plurality; the patella fixing pieces are arranged in a central symmetry manner and are uniformly fixed on the second surface;

the patella fixing piece is one or more of a stud, a cylinder, a conical column, a triangular column, a rectangular column, a pentagonal column or a hexagonal column.

Further, the patella fixing piece and the patella support are integrally formed; the top cover and the patella support are detachably and fixedly connected through a connecting piece;

the top cover and the patella support are respectively provided with a prosthesis connecting hole corresponding to the connecting piece;

the connecting piece is one or more of a stud, a cylinder, a conical column, a triangular column, a rectangular column, a pentagonal column or a hexagonal column.

Further, the top cover is made of cobalt-chromium-molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic;

the patella support is made of stainless steel, ultra-high molecular weight polyethylene, cobalt-chromium-molybdenum alloy or titanium alloy;

the rotor is made of cobalt-chromium-molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic;

the connecting piece is made of titanium alloy or stainless steel.

Based on the second object, the artificial knee joint provided by the application comprises the patella prosthesis.

The application has the beneficial effects that:

the patella prosthesis comprises a prosthesis main body, a rotator and a patella fixing piece, wherein a main body groove which is matched and connected with the rotator is formed in the prosthesis main body, the main body groove can prevent the rotator from being separated from the prosthesis main body, and the rotator can rotate around the axis of the rotator, so that the patella prosthesis keeps contact with a normal femoral condyle or a femoral condyle prosthesis of a human body through the rotator, and a friction pair formed by the patella prosthesis and the normal femoral condyle or the femoral condyle prosthesis of the human body is rolling friction, so that abrasion of the patella prosthesis is greatly reduced, and the service life of the knee joint prosthesis is prolonged.

The artificial knee joint provided by the application comprises the patella prosthesis, so that the abrasion of the patella prosthesis can be reduced, and the service life of the knee joint prosthesis can be prolonged.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present application, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

FIG. 1 is an exploded view of a patella prosthesis according to an embodiment of the present application;

FIG. 2 is an exploded view of a patella prosthesis according to another embodiment of the present application;

fig. 3 is a schematic view of a first angle structure of a patella prosthesis according to an embodiment of the present application;

FIG. 4 is a left cross-sectional view of the patella prosthesis shown in FIG. 3;

FIG. 5 is a schematic view of the patella prosthesis shown in FIG. 4 without the rotator shown;

FIG. 6 is a top view of the patella prosthesis shown in FIG. 3;

FIG. 7 is a bottom view of the patella prosthesis shown in FIG. 3;

fig. 8 is a schematic view of a second angle structure of a patella prosthesis according to an embodiment of the present application;

FIG. 9 is a schematic view of a third angular configuration of a patella prosthesis according to an embodiment of the present application;

fig. 10 is a schematic perspective view of a rotator of a patella prosthesis according to an embodiment of the present application;

fig. 11 is a front view of a rotator of a patella prosthesis according to an embodiment of the present application;

fig. 12 is a schematic perspective view of a patellar support of a patella prosthesis according to an embodiment of the present application;

fig. 13 is a front view of a patellar rest of a patella prosthesis according to an embodiment of the present application.

Icon: 100-a prosthesis body; 110-a first side; 120-a second side; 130-a body groove; 140-top cap; 150-patella support; 160-a connector; 170-a prosthesis attachment aperture; 200-rotating body; 300-patella mount; 400-rolling elements; 410-rolling grooves.

Detailed Description

The following description of the embodiments of the present application will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the application are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

In the description of the present application, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

Example 1

Referring to fig. 1-13, the present embodiment provides a patella prosthesis; fig. 1 and 2 are exploded views of the patella prosthesis according to the present embodiment from two perspectives; fig. 3 is a schematic view of a first angle structure of the patella prosthesis according to the present embodiment, which may also be understood as a front view of the patella prosthesis, fig. 4 is a left cross-sectional view, and fig. 6 is a top view; FIG. 7 is a bottom view; for a clearer illustration of the structure, fig. 5 is a schematic view of the patella prosthesis shown in fig. 4, without the rotator shown; fig. 8 and 9 are schematic views of two angles of the patella prosthesis according to the present embodiment; fig. 10 is a schematic perspective view of a rotor according to the present embodiment, and fig. 11 is a front view of the rotor; fig. 12 is a schematic perspective view of the patella support according to the present embodiment, and fig. 13 is a front view of the patella support.

Referring to fig. 1 to 13, the patella prosthesis provided in this embodiment includes a prosthesis body 100, a rotator 200, and a patella fastener 300.

The prosthesis body 100 has corresponding first and second faces 110, 120.

The prosthesis body 100 is provided with a body groove 130 cooperatively coupled with the rotator 200; optionally, the first face 110 is provided with a main body recess 130 in mating connection with the rotor 200.

Optionally, the second face 120 is coupled to the patella mount 300. The whole of the patella prosthesis is fixed to the patella by the patella fastener 300 in order to fix the patella prosthesis to the patella of the human body, for example, by means of bone cement or a bio-coating.

The body groove 130 can prevent the rotator 200 from being separated from the prosthesis body 100; i.e., the rotator 200 is not dropped from the prosthesis body 100 when rotated. The structure of the body groove 130 capable of preventing the rotator 200 from being separated from the prosthesis body 100 includes, but is not limited to, that the rotator 200 and the body groove 130 of the prosthesis body 100 are provided with a limit structure that cooperates with each other, that the notch of the body groove 130 of the prosthesis body 100 is provided with a stop ring for preventing the rotator 200 from being separated, and that the rotator 200 and the body groove 130 of the prosthesis body 100 adopt conical surface cooperation, cambered surface cooperation, etc.

The rotor 200 protrudes from the first surface 110, and the rotor 200 can rotate around its own axis. The rotator 200 is raised above the first surface 110 such that the rotator 200 contacts a normal femoral condyle or femoral condyle prosthesis of a human. The rotator 200 may be, for example, a truncated cone-like body, a spherical cone, or the like; optionally, the rotator 200 is a truncated cone. Alternatively, the rotator 200 can rotate 45-360 degrees around its own axis; alternatively, the rotator 200 can be rotated 360 degrees around its own axis.

The patella prosthesis in this embodiment includes a prosthesis main body 100, a rotator 200 and a patella fixing member 300, in which a main body groove 130 is disposed on the prosthesis main body 100 and is cooperatively connected with the rotator 200, the main body groove 130 can prevent the rotator 200 from separating from the prosthesis main body 100, and the rotator 200 can rotate around its own axis, so that the patella prosthesis keeps contact with a normal femoral condyle or a femoral condyle prosthesis of a human body through the rotator 200, and a friction pair formed by the patella prosthesis and the normal femoral condyle or the femoral condyle prosthesis of the human body is rolling friction, thereby greatly reducing wear of the patella prosthesis and prolonging service life of the knee joint prosthesis.

It is known from physical knowledge that the wear of rolling friction is significantly lower than sliding friction; in this embodiment, the patella prosthesis adopts the design principle of rolling friction, replaces the traditional design thought of sliding friction, designs a rotator 200 capable of freely rotating along the axis of the patella prosthesis, and in the knee joint flexion and extension movement process, the rotator 200 on the patella prosthesis always keeps contact with the normal femoral condyle or the femoral condyle prosthesis of the human body, and along with different contact positions, the rotator 200 freely rotates along with the contact positions, for example, freely rotates for 360 degrees, so that the patella prosthesis is ensured to be in a low-abrasion movement state for a long time, and the service life of the knee joint prosthesis is remarkably prolonged. Meanwhile, the patella prosthesis is always in a low-abrasion state, so that the phenomena of patella complications, such as subluxation and dislocation of the patella, patella looseness, gonalgia and the like, which are originally caused after the traditional artificial knee joint replacement operation, are also reduced, and the life quality of patients is greatly improved.

Referring to fig. 1-9, in an alternative version of the present embodiment, the prosthesis body 100 includes a cap 140 and a patella bearing 150.

The cap 140 is fixedly connected to the patella bearing 150.

The first surface 110 is a surface of the cap 140 away from the patella bearing 150, and the second surface 120 is a surface of the patella bearing 150 away from the cap 140. The prosthesis body 100 is designed to be two parts of the top cover 140 and the patella bearing 150, and the rotator 200 is conveniently installed and connected in the prosthesis body 100 through a split assembly mode.

Optionally, the top cover 140 is provided with a main body groove 130, and the rotator 200 is connected to the patella bearing 150. That is, the body groove 130 penetrates the top cover 140, the rotation surface of the rotator 200 is connected to the top cover 140, the bottom surface of the rotator 200 is connected to the patella bearing 150, and the top surface of the rotator 200 is connected to the first surface 110.

To facilitate rotation of rotator 200, rotator 200 is coupled to patella bearing 150 by rolling elements 400; the rolling bodies 400 reduce friction between the rolling bodies 200 and the patella support 150 when the rolling bodies 200 rotate, so that the rolling bodies 200 rotate in the prosthesis main body 100 more flexibly, abrasion of the patella prosthesis is further reduced, and the service life of the knee prosthesis is prolonged. Alternatively, the number of rolling bodies 400 is a plurality, for example, the number of rolling bodies 400 is 6-20, for example, the number of rolling bodies 400 is 6, 8, 9, 10, 12, 15, or the like.

According to the patella prosthesis in the embodiment, the design principle of rolling friction and thrust bearing is adopted through the rotator 200 and the rolling body 400 to replace the traditional design thought of sliding friction, so that the abrasion of the patella prosthesis is greatly reduced, and the service life of the knee joint prosthesis is remarkably prolonged.

Referring to fig. 10-13, further, the rotator 200 and/or the patella bearing 150 is provided with a rolling groove 410 that mates with the rolling body 400; that is, the rotator 200 is provided with the rolling grooves 410 that mate with the rolling bodies 400, or the patella bearing 150 is provided with the rolling grooves 410 that mate with the rolling bodies 400, or both the rotator 200 and the patella bearing 150 are provided with the rolling grooves 410 that mate with the rolling bodies 400. By rolling the grooves 410, the rolling bodies 400 are rolled better. Optionally, both rotator 200 and patella bearing 150 are provided with rolling grooves 410 that mate with rolling bodies 400. Optionally, the rolling grooves 410 of the rotator 200 and the rolling grooves 410 of the patella support 150 are semicircular in cross section; alternatively, the rolling grooves 410 provided on the rotator 200 have the same diameter as the rolling bodies 400, and the rolling grooves 410 provided on the patella bearing 150 have the same diameter as the rolling bodies 400; the diameter may range, for example, from 1mm to 4mm, and the diameter may be, for example, 1mm, 1.5mm, 2mm, 2.2mm, 3mm, 3.5mm, and the like. Optionally, the rolling bodies 400 substantially fill the rolling grooves 410; further, in order to secure a good rolling effect, a rolling bracket for connecting the rolling bodies 400 is provided in the rolling groove 410. Alternatively, the rolling bodies 400 are spheres, cylinders, cones, or the like.

Those skilled in the art will appreciate that the rotator 200 and the patella bearing 150 may also be coupled by bearings to reduce friction between the rotator 200 and the patella bearing 150 as the rotator 200 rotates.

In an alternative of this embodiment, the surface of the rotator 200 close to the patella support 150, the surface of the patella support 150 close to the rotator 200, the outer circumferential surface of the rotator 200 matching the cap 140, and the inner circumferential surface of the cap 140 matching the rotator 200 are important friction interfaces of the patella prosthesis. For example, when the patellar prosthesis is implanted in a human body, the rotator 200 will have contact friction with the normal femoral condyle or femoral condyle prosthesis of the human body, so the side of the rotator 200 near the patellar support 150 is an important friction interface; meanwhile, as the patella moves, the rotator 200 rotates under the eccentric load according to the contact position, friction is formed on the surface of the patella support 150, which is close to the rotator 200, the outer circumferential surface of the rotator 200, which is matched with the top cover 140, and the inner circumferential surface of the top cover 140, which is matched with the rotator 200, while rotating, so that these contact surfaces are also important friction interfaces.

Optionally, the surface roughness Ra of the side of the rotator 200 near the patella rest 150 ranges from: ra is less than or equal to 1.5 mu m.

Optionally, the surface roughness Ra of the surface of the patella bearing 150 adjacent to the rotator 200 may range from: ra is less than or equal to 0.1 mu m. Preferably, the surface roughness Ra of the surface of the patella bearing 150 adjacent to the rotator 200 ranges from: ra is less than or equal to 1.5 mu m.

Alternatively, the range of the surface roughness Ra of the outer peripheral surface of the rotor 200 mated with the top cover 140 is: ra is less than or equal to 1.5 mu m.

Alternatively, the range of the surface roughness Ra of the inner peripheral surface of the top cover 140 mated with the rotator 200 is: ra is less than or equal to 1.5 mu m.

In an alternative of this embodiment, the rotator 200 is connected to the top cover 140 by conical surface fit; alternatively, the taper angle of the taper surface of the rotor 200 mating with the top cover 140 is the same as the taper angle of the taper surface of the top cover 140 mating with the rotor 200. By employing a tapered fit, the rotator 200 is prevented from disengaging the cap 140 and thus the rotator 200 is prevented from disengaging the prosthesis body 100.

Optionally, the cone angle a of the cone is in the range of: a is more than or equal to 5 degrees and less than or equal to 45 degrees. The taper angle a may be, for example, 5 °, 10 °, 18 °, 35 °, 38 °, 45 °, and so on.

Alternatively, the rotator 200 is spaced apart from the top cover 140; i.e., the conical surface of the rotor 200 mating with the top cover 140, and the conical surface of the top cover 140 mating with the rotor 200 are spaced apart to reduce or avoid friction between the rotor 200 and the top cover 140 when the rotor 200 is rotated. Alternatively, the gap between the rotator 200 and the top cover 140 is 0.01mm-0.08mm. Preferably, the gap between the rotator 200 and the top cover 140 is 0.01mm-0.05mm.

In an alternative of this embodiment, the first surface 110 is a curved surface; optionally, the first surface 110 is a symmetrical curved surface or an asymmetrical curved surface; preferably, the first face 110 is a spherical or ellipsoidal spherical cap; that is, the surface of the top cover 140 far away from the patella support 150 is a spherical cap or an ellipsoidal spherical cap; so as to reduce or avoid discomfort and pain of the human body caused by the patella prosthesis in the knee joint bending and stretching movement process.

Optionally, the radius of the spherical crown is 15mm-45mm; preferably, the radius of the spherical cap is 20mm-40mm. Optionally, the radius of the spherical cap is equal to or greater than the radius of the rotator 200.

Alternatively, the major radius of the ellipsoidal spherical cap is 25mm-45mm and the minor radius of the ellipsoidal spherical cap is 15mm-35mm. Alternatively, the short radius of the ellipsoidal spherical cap is greater than the radius of the rotator 200.

Optionally, rotator 200 is smoothly transition-coupled to first surface 110 to further reduce or avoid discomfort and pain to the person caused by the patella prosthesis during flexion and extension movements of the knee joint. Alternatively, rotor 200 uses the same design parameters as first face 110 to achieve a relatively perfect interface. Preferably, the rotator 200 and the first surface 110 adopt an arc surface having the same curvature.

In an alternative to this embodiment, the number of patella fasteners 300 is multiple; the number of patella fasteners 300 may be, for example, 2-10, such as 2, 3, 6, 8, etc.

Optionally, the patella fixtures 300 are disposed in central symmetry and uniformly fixed on the second surface 120; optionally, the patella mount 300 is integrally formed with the patella bracket 150.

Optionally, the patella fastener 300 is one or more of a stud, a cylinder, a conical cylinder, a triangular cylinder, a rectangular cylinder, a pentagonal cylinder, or a hexagonal cylinder; the patella mount 300 may also be other shapes. Alternatively, the patella mount 300, when circular in cross-sectional shape, is preferably 4mm-8mm in diameter; alternatively, when the patella mount 300 has a cross-sectional shape other than circular, the area of the cross-section ranges from 12mm ² -25mm ² 。

In an alternative of this embodiment, the top cover 140 and the patella support 150 are detachably and fixedly connected by a connecting member 160; optionally, the number of connectors 160 is a plurality; the number of connectors 160 may be, for example, 2-10, such as 2, 3, 6, 8, etc. Optionally, the plurality of connectors 160 are arranged in a central symmetry.

Optionally, the connector 160 is spaced apart from the patella mount 300 so as not to interfere with each other.

Optionally, the cap 140 and the patella rest 150 are each provided with a prosthetic connection aperture 170 corresponding to the connector 160; preferably, the shape of the prosthetic connection aperture 170 may be a screw thread or a light aperture. Optionally, the threaded hole is metric or english; when the prosthetic connection hole 170 is designed with a metric thread, the nominal diameter of the thread is 1.5mm-5mm; when the prosthetic connection hole 170 is designed with english threads, the nominal diameter of the threads is 0.059inch-0.197inch. Alternatively, whenWhen the cross section of the prosthesis connecting hole 170 is circular, the diameter is 1.5mm-5mm; alternatively, when the cross-sectional shape of the prosthetic connection hole 170 is a shape other than a circle, the average area of the cross-section of the prosthetic connection hole 170 is 1.5mm ² -20mm ² 。

Optionally, the connection 160 is one or more of a stud, a cylinder, a conical column, a triangular column, a rectangular column, a pentagonal column, or a hexagonal column; the connector 160 may also be other shapes. The number of prosthesis attachment holes 170 corresponds to the number of connectors 160; the shape of the prosthesis attachment aperture 170 corresponds to the shape of the attachment element 160. Optionally, the connection 160 is screwed and/or interference fit with the prosthetic connection hole 170 of the cap 140, and the connection 160 is a small clearance fit with the prosthetic connection hole 170 of the patella bearing 150 to ensure a rotational clearance between the rotator 200 and the body recess 130.

In an alternative embodiment, the top cover 140 is made of cobalt-chromium-molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic. Optionally, the top cover 140 made of cobalt-chromium-molybdenum alloy material or ultra-high molecular weight polyethylene material is formed by adopting traditional numerical control processing, and detection can be realized by a common measuring tool; optionally, the top cover 140 made of alumina-based ceramic material or zirconia-based ceramic material is formed by adopting a processing mode of isostatic pressing, rough machining forming, sintering, finish machining grinding and polishing, and the common measuring tool can realize inspection; so that the top cover 140 does not have any design, manufacturing process and inspection difficulties.

Optionally, the patella support 150 is made of stainless steel, ultra-high molecular weight polyethylene, cobalt-chromium-molybdenum alloy or titanium alloy; optionally, the patella support 150 made of stainless steel, ultra-high molecular weight polyethylene, cobalt-chromium-molybdenum alloy or titanium alloy material is formed by adopting traditional numerical control machining, and the detection can be realized by a common measuring tool; so that the patella bearing 150 does not have any design, manufacturing process, and inspection difficulties.

Optionally, the material of the rotator 200 is cobalt-chromium-molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic; optionally, the rotor 200 made of cobalt-chromium-molybdenum alloy material or ultra-high molecular weight polyethylene material is formed by adopting traditional numerical control processing, and the detection can be realized by a common measuring tool; optionally, the rotator 200 made of alumina-based ceramic material or zirconia-based ceramic material is formed by adopting a processing mode of isostatic pressing, rough machining forming, sintering, finish machining grinding and polishing, and the common measuring tool can realize inspection; so that the rotor 200 does not have any difficulty in design, production process, and inspection.

Optionally, the material of the connecting member 160 is titanium alloy or stainless steel. Optionally, the connecting piece 160 made of stainless steel or titanium alloy material is formed by adopting traditional numerical control machining, and the detection can be realized by a common measuring tool; so that the connection 160 does not have any design, manufacturing process and inspection difficulties.

Optionally, the rolling element 400 is made of cobalt-chromium-molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic; optionally, the rolling body 400 made of cobalt-chromium-molybdenum alloy material or ultra-high molecular weight polyethylene material is formed by adopting traditional numerical control machining, and the detection can be realized by a common measuring tool; optionally, the rolling body 400 made of alumina-based ceramic material or zirconia-based ceramic material is formed by adopting a processing mode of isostatic pressing, rough machining forming, sintering, finish machining grinding and polishing, and the common measuring tool can realize inspection; so that the rolling element 400 does not have any difficulty in design, production process, and inspection.

Alternatively, the materials of the cap 140, the patella support 150, the rotator 200, the connector 160, the patella mount 300, the rolling body 400, etc. may be the same or different.

In the artificial knee joint replacement, a special surgical instrument is used for performing patella osteotomy operation so as to ensure all installation and matching precision.

Example two

A second embodiment provides an artificial knee joint, where the second embodiment includes the patella prosthesis described in the first embodiment, and technical features of the patella prosthesis disclosed in the first embodiment are also applicable to the second embodiment, and technical features of the patella prosthesis disclosed in the first embodiment are not repeated.

The artificial knee joint provided by the embodiment comprises a patella prosthesis. The patella fixing part of the patella prosthesis can fix the patella prosthesis on the patella of the osteotomy of the human body in a way of bone cement or biological coating.

In the embodiment, the artificial knee joint is formed by a rolling friction pair consisting of the patella prosthesis and a normal femoral condyle or a femoral condyle prosthesis of a human body, so that the abrasion of the patella prosthesis is greatly reduced, and the service life of the knee joint prosthesis is prolonged; the artificial knee joint has advantages of the patella prosthesis of embodiment one, and the advantages of the patella prosthesis of embodiment one disclosed herein are not repeated here.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the application.

Claims

1. A patella prosthesis, which is characterized by comprising a prosthesis main body, a rotator and a patella fixing piece;

the body groove is capable of preventing the rotor from being separated from the prosthesis body; the rotating body protrudes out of the first surface, and the rotating body can rotate around the axis of the rotating body;

the prosthesis body includes a cap and a patella support; the top cover is fixedly connected with the patella support;

the top cover is provided with the main body groove, and the rotator is connected with the patella support;

the rotator is connected with the patella support through a rolling body; the rotator and/or the patella support are provided with rolling grooves matched with the rolling bodies;

the rotator and the top cover are connected in a conical surface fit manner; the first surface is a spherical crown or an ellipsoidal spherical crown; the rotating body is in smooth transitional connection with the first surface.

2. The patella prosthesis according to claim 1, wherein the surface roughness Ra of the surface of the rotator adjacent to the patella support, the surface of the patella support adjacent to the rotator, the outer circumferential surface of the rotator mated with the cap, and the inner circumferential surface of the cap mated with the rotator ranges from: ra is less than or equal to 1.5 mu m.

3. The patella prosthesis according to claim 1, wherein the taper angle a of the taper surface ranges from: a is more than or equal to 5 degrees and less than or equal to 45 degrees.

4. The patella prosthesis according to claim 1, wherein the spherical crown has a radius of 15mm-45mm, the ellipsoidal crown has a major radius of 25mm-45mm, and the ellipsoidal crown has a minor radius of 15mm-35mm.

5. The patellar prosthesis according to claim 1, wherein the number of patella fixtures is a plurality; the patella fixing pieces are arranged in a central symmetry manner and are uniformly fixed on the second surface;

6. The patellar prosthesis according to claim 1, wherein the patella fastener is integrally formed with the patellar bracket; the top cover and the patella support are detachably and fixedly connected through a connecting piece;

7. The patella prosthesis according to claim 6, wherein the cap is made of cobalt chrome molybdenum alloy, ultra-high molecular weight polyethylene, alumina-based ceramic or zirconia-based ceramic;

the connecting piece is made of titanium alloy or stainless steel.

8. An artificial knee joint comprising the patella prosthesis according to any of claims 1-7.