CN201175391Y

CN201175391Y - Knee joint endoprosthesis

Info

Publication number: CN201175391Y
Application number: CNU2008200618339U
Authority: CN
Inventors: 张国亮; 姚进; 裴福兴; 沈彬; 周宗科
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2008-01-17
Filing date: 2008-01-17
Publication date: 2009-01-07
Anticipated expiration: 2018-01-17

Abstract

The utility model provides a false body for knee joint. The false body comprises: a thighbone false body 1 connected with the far end of the thighbone, a shinbone pad 4 fixed on the shinbone support 5, a shinbone support 5 connected with the proximal end of the shinbone, shinbone intercondylar crista 3 arranged in an intercondylar hole 4c of the shinbone pad 4 and a lug boss 5f hole of the shinbone support 5, and a bolt 2 ensuring the corresponding position of the shinbone intercondylar crista 3 with the shinbone pad 4 and the shinbone support 5. The articular surfaces of an endoskeleton 4a and an ectocondyle 4b of the shinbone pad 4 respectively correspond to the articular surfaces of an endoskeleton 1a and an ectocondyle 1b of the thighbone false body 1 to ensure that the thighbone false body 1 can stretch and roll back on the shinbone pad 4. The shinbone intercondylar crista 3 stretches into an intercondylar area 1d of the thighbone false body 1 to ensure the stretching stability of the knee joint; the shinbone intercondylar crista 3 close to the ectocondyle 1b of the thighbone false body 1 is excised to ensure that the thighbone false body 1 has larger outward rotation angle when going down the knee, thereby achieving deep flexure of the knee joint.

Description

Knee-joint endoprosthesis

Technical field

This utility model relates to a kind of medical artificial joint, relates in particular to a kind of knee-joint endoprosthesis that is applied to human body, in knee arthroplasty, is used for replacing the human body natural's knee joint that causes all or part of afunction owing to reasons such as pathological changes or damages.

Background technology

The history of the development of artificial knee joint surplus the present existing 40 year when human body natural's knee joint causes all or part of afunction owing to reasons such as pathological changes or damages, just need be replaced with artificial knee joint, with the reconstruction knee joint, alleviates patient's slight illness.

Usually said knee-joint endoprosthesis comprises femoral prosthesis and tibial prosthesis two large divisions.Wherein, femoral prosthesis by femur stem is installed or screw is connected with distal femur, has internal skeleton condyle and dermoskeleton condyle.Tibial prosthesis is divided into tibia liner and tibial bearing two parts, tibial bearing is fixed on proximal tibia, the tibia liner is between femoral prosthesis and tibial bearing, be fixed on the tibial bearing, in it dermoskeleton facies artieularis malleolaris respectively with femoral prosthesis in the dermoskeleton facies artieularis malleolaris be complementary, to simulate normal human body natural's motion of knee joint process.

For human body natural's knee joint, when knee joint when being in knee-expanding position, ridge stretches in the femoral intercondylar groove between the tibia condyle, with ligament and soft tissue have been realized kneed stability jointly on every side, when knee joint when knee-expanding position begins to go down on one's knees gradually, the outward turning angle of the relative tibia of femur increases gradually.So in knee-joint endoprosthesis, ridge is to realize kneed knee-expanding position stability between design tibia condyle, simultaneously, ridge can increase the outward turning angle of the relative tibial prosthesis of femoral prosthesis between the tibia condyle, to increase kneed angle of bend.In U.S. Pat 6793680, proposed a kind of new of ridge between the tibia condyle, ridge protrudes in the knee joint front part between its tibia condyle, to realize kneed knee-expanding position stability, recessed at rear section, the outward turning angle of the relative tibial prosthesis of femoral prosthesis when going down on one's knees with increase.In U.S. Pat 7066963, among the US6902582, the ridge front part is higher than rear section between the tibia condyle, realizes kneed knee-expanding position stability on the one hand, increases the outward turning angle of the relative tibial prosthesis of femoral prosthesis when going down on one's knees on the other hand.But ridge and tibia liner all are an integral body between the tibia condyle in these patents, and when the wearing and tearing of ridge between the tibia condyle increased, the life-span of whole tibia liner will reduce, thereby influences the kinetic stability of knee-joint endoprosthesis.

Summary of the invention

Deficiency at above technology and patent, the utility model proposes a kind of new human body knee joint endoprosthesis, purpose is: at first, when knee joint when being in knee-expanding position, ridge stretches in the femoral intercondylar groove between the tibia condyle, with the kneed stability of the common realization of ligament and soft tissue on every side.Secondly, ridge can increase the outward turning angle of the relative tibial prosthesis of femoral prosthesis between the tibia condyle, increasing kneed angle of bend, and realizes the knee joint deep flexion.At last, ridge and tibia liner separate design between the tibia condyle, ridge adopts wear-resistant metal material to make between the tibia condyle, with the anti-wear performance of ridge between raising tibial prosthesis condyle, and then the kinetic stability of assurance knee-joint endoprosthesis.

Knee-joint endoprosthesis described in this utility model is applicable to knee joint peripheral ligament and the intact patient of soft tissue function.

The concrete formation of this device:

Femoral prosthesis 1, this prosthese is connected with distal femur, has internal skeleton condyle 1a, dermoskeleton condyle 1b and intercondylar area territory 1d;

Tibial bearing 5, this bearing is connected with proximal tibia;

Tibia liner 4, this liner is fixed on the tibial bearing 5, has internal skeleton condyle 4a and dermoskeleton condyle 4b;

Ridge 3 between the tibia condyle, and in the hole 4c that packs between tibia liner 4 condyles and in the tibial bearing 5 boss 5f holes, top peripheral is made up of face 3a, 3b, 3c, 3d, 3e,, wherein 3e is the inclined-plane;

Screw 2 links to each other with the boss 5f of hole 4c and tibial bearing 5 between the condyle of tibia liner 4.

The technical scheme that this device is implemented:

When knee joint by enuflex position during gradually to knee-expanding position, ridge 3 stretches in the intercondylar area territory 1a of femoral prosthesis gradually between the tibia condyle, its top peripheral face 3a, 3b, 3c, 3d match with femoral prosthesis intercondylar area territory 1d, to guarantee the kneed knee joint stability of stretching.

When kneed angle of bend increases gradually, the outward turning angle of femoral prosthesis 1 increases gradually, it is cut that ridge 3 is close to the part of femoral prosthesis 1 dermoskeleton condyle 1b between the tibia condyle, the top peripheral face 3e that is ridge 3 between the tibia condyle is the inclined-plane, and the counterclockwise angle of 3e and vertical curve T is B, at this moment, the rear section 1c of femoral prosthesis 1 dermoskeleton condyle 1b not can and the tibia condyle between ridge 3 interfere, thereby guarantee that femoral prosthesis 1 has bigger outward turning angle when enuflex position, increasing kneed angle of bend, and finally realize the knee joint deep flexion.

The utility model has the advantages that: at first, can realize the kneed knee joint stability of stretching.Secondly, the outward turning angle of the relative tibial prosthesis of femoral prosthesis increases, and can increase kneed angle of bend and realize the knee joint deep flexion.At last, ridge adopts wear-resistant metal material to make between the tibia condyle, and this not only can improve the bulk life time of knee-joint endoprosthesis, and can guarantee the kinetic stability of knee-joint endoprosthesis.

Description of drawings

Fig. 1 knee-joint endoprosthesis decomposition diagram

Fig. 2 tibial prosthesis front view

Fig. 3 is about the cutaway view of Fig. 2 section line K-K

Fig. 4 is about the cutaway view of Fig. 2 section line H-H

Fig. 5 is about the symmetrical instance graph of ridge between the tibia condyle

Sequence number among the figure, 1. femoral prosthesis, 2. screw, 3. ridge between the tibia condyle, 4. tibia liner, 5. tibial bearing A. knee joint front side, P. knee joint rear side, M. knee joint inboard, the L. knee joint outside

The specific embodiment

In Fig. 1, Fig. 2, Fig. 3 and Fig. 4, femoral prosthesis 1 is made by cobalt-chromium-molybdenum alloy material, is connected with distal femur by femur installation stem or screw, has internal skeleton condyle 1a and dermoskeleton condyle 1b.Tibial bearing 5 is made by cobalt-chromium-molybdenum alloy material, by tibia stem 5c is installed and is connected with proximal tibia with fixed leg 5b, 5d, wherein, tibia is installed stem 5c and is pressed into the tibia pulp cavity, play main fixation, fixed leg 5b, 5d are pressed into the proximal tibia osteotomy surface, play anti-rotation and auxiliary fixation.Tibia liner 4 is made by superhigh molecular weight polyethylene material, between femoral prosthesis 1 and tibial bearing 5, have internal skeleton condyle 4a and dermoskeleton condyle 4b, realize the location of tibia liner 4 by protruding 5a and 5e along M-L direction (interior-outer direction) along tibial bearing A-P direction (front-rear direction), by tibia liner 4 upper edge A-P direction (front-rear direction)

bayonet socket face

4c, 4d and tibial bearing 5 are along A-P direction (front-rear direction) bayonet socket face 5h, the cooperation of 5j realizes that tibia liner 4 is along the location of A-P direction (front-rear direction) with fixed, simultaneously, can prevent tibia liner 4 upward dislocations.Ridge 3 is made by wear-resistant metal material between the tibia condyle, packs between tibia liner 4 condyles in the 4c of hole and in the tibial bearing 5 boss 5f holes.The 2b of screw 2 partly stretches into the respective aperture of ridge 3 between the tibia condyle, ridge 3 and tibia liner 4 are located with the relative position of tibial bearing 5 between the realization condyle, the 2a of screw 2 partly is an external screw thread, be connected with the respective screw hole of tibia liner 4, ridge 3 and tibia liner 4 are fixed with the relative position of tibial bearing 5 between the realization condyle.

In Fig. 1, when knee joint by enuflex position gradually to knee-expanding position, or by knee-expanding position during gradually to enuflex position, the internal skeleton condyle 1a articular surface of femoral prosthesis 1 and dermoskeleton condyle 1b articular surface are complementary with the internal skeleton condyle 4a articular surface and the dermoskeleton condyle 4b articular surface of tibia liner 4 respectively, realizing the bending of femoral prosthesis 1 on tibia liner 4, slide and to roll action such as back, thereby simulate normal human body natural's motion of knee joint process

In Fig. 1 and Fig. 2, when knee joint by enuflex position during gradually to knee-expanding position, ridge 3 stretches in the intercondylar area territory 1d of femoral prosthesis gradually between the tibia condyle, and its top peripheral face 3a, 3b, 3c, 3d match with femoral prosthesis intercondylar area territory 1d, to guarantee the kneed knee joint stability of stretching.

In Fig. 1 and Fig. 2, when knee joint is gone down on one's knees gradually by knee-expanding position, and when increasing gradually along with angle of bend, femoral prosthesis 1 carries out outward turning along the relative tibia liner 4 of the direction of R shown in Fig. 2, and the outward turning angle increases gradually, it is cut that ridge 3 is close to the part of femoral prosthesis 1 dermoskeleton condyle 1b between the tibia condyle, the top peripheral face 3e that is ridge 3 between the tibia condyle is the inclined-plane, and the counterclockwise angle of 3e and vertical curve T is B, at this moment, the rear section 1c of femoral prosthesis 1 dermoskeleton condyle 1b not can and the tibia condyle between ridge 3 interfere, thereby guarantee that femoral prosthesis 1 has bigger outward turning angle when enuflex position, increasing kneed angle of bend, and finally realize the knee joint deep flexion.The size of included angle B can be selected, thereby can insert ridge 3 between only tibia condyle according to patient's practical situation.

Ridge 3 or 3 ' adopts wear-resistant metal material to make between the tibia condyle, so, in knee joint by enuflex position gradually to knee-expanding position, or by knee-expanding position during gradually to enuflex position, ridge 3 or the 3 ' wear extent with respect to femoral prosthesis 1 reduce greatly between the tibia condyle, this not only can improve the bulk life time of knee-joint endoprosthesis, and can guarantee the kinetic stability of knee-joint endoprosthesis.

Knee-joint endoprosthesis is applicable to the right side knee joint shown in Fig. 1, Fig. 2, Fig. 3 and Fig. 4.

In Fig. 2, ridge 3 between the tibia condyle is changed to ridge symmetry example 3 ' between tibia condyle shown in Figure 5, knee-joint endoprosthesis as herein described is equally also applicable to the left side knee joint.

Claims

1. knee-joint endoprosthesis is characterized in that:

Femoral prosthesis (1), this prosthese is connected with distal femur, has internal skeleton condyle (1a), dermoskeleton condyle (1b) and intercondylar area territory (1d);

Tibial bearing (5), this bearing is connected with proximal tibia;

Tibia liner (4), this liner are fixed on the tibial bearing (5), have internal skeleton condyle (4a) and dermoskeleton condyle (4b);

Ridge between the tibia condyle (3), in the hole (4c) of packing between tibia liner (4) condyle and in tibial bearing (5) boss (5f) hole, top peripheral is made up of face (3a), (3b), (3c), (3d), (3e), and wherein top peripheral face (3e) is the inclined-plane;

Screw (2) links to each other with the boss (5f) of hole (4c) and tibial bearing (5) between the condyle of tibia liner (4).

2. knee-joint endoprosthesis according to claim 1, it is characterized in that, when knee-expanding position, ridge between the tibia condyle (3) stretches in the intercondylar area territory (1a) of femoral prosthesis, its top peripheral face (3a), (3b), (3c), (3d) match with femoral prosthesis intercondylar area territory (1a), to guarantee the kneed knee joint stability of stretching.

3. knee-joint endoprosthesis according to claim 1, it is characterized in that, it is cut that ridge between the tibia condyle (3) is close to the part of femoral prosthesis (1) dermoskeleton condyle (1b), the top peripheral face (3e) that is ridge between the tibia condyle (3) is the inclined-plane, and top peripheral face (3e) is (B) with the counterclockwise angle of vertical curve (T), guaranteeing that femoral prosthesis (1) has bigger outward turning angle when the enuflex position, thereby increase kneed angle of bend, and finally realize the knee joint deep flexion.