WO2022231260A1

WO2022231260A1 - Artificial knee joint bearing element having reverse slope

Info

Publication number: WO2022231260A1
Application number: PCT/KR2022/005922
Authority: WO
Inventors: 이장연
Original assignee: 이장연
Priority date: 2021-04-26
Filing date: 2022-04-26
Publication date: 2022-11-03
Also published as: KR20220146930A; KR102608868B1

Abstract

The present invention relates to an artificial knee joint bearing element having a reverse slope and, more particularly, an artificial knee joint bearing element having a reverse slope, comprising: a bearing body which has a downwardly depressed articular surface with a curved shape so that an artificial knee joint femoral element can slide on the articular surface; and a sloped portion which is provided to extend downwardly from the bearing body and to come into contact with a tibial element, and which is formed to be sloped on at least one side, wherein the sloped portion extends downward from the bearing body from the anterior side to the posterior side such that the overall slope of the artificial knee joint system is maintained to be gentle, and the tibia is cut along the patient's own tibial slope to avoid excessive cutting of bone, thereby reducing complications and sequelae after artificial knee replacement surgery and improving the durability of an artificial knee joint implant. The present invention relates to a bearing element having a reverse slope as opposed to a conventional bearing having a gentle posterior slope, wherein when the lower surface thereof is placed on the floor parallel to the ground, the anterior side is low and the posterior side is high, providing a slope opposite to the reverse slope of existing bearing designs in which the anterior side is high and the posterior side is low.

Description

Artificial knee joint bearing element with reverse inclination

The present invention relates to an artificial knee joint bearing element having a reverse inclination, and more particularly, a bearing body having a curved shape and having a downwardly depressed articular surface so that the artificial knee joint femoral element can slide on the joint surface, the It extends downward from the bearing body and is provided to come into contact with the tibial element, and includes an inclined portion formed to be inclined to at least one side, wherein the inclined portion is formed to have an anterior inclination rising from the rear to the front, and the bearing body is formed to be inclined from the front to the rear. It extends downward from the knee joint system and maintains the overall inclination of the artificial knee joint system gently, but cuts the tibia along the patient's own tibial inclination to avoid excessive fracture agents, thereby reducing complications and sequelae after artificial knee arthroplasty. It relates to an artificial knee joint bearing element having a reverse inclination that can improve the durability of a knee joint insert. The present invention is a bearing element having a reverse slope as opposed to a conventional bearing having a gentle rear slope. It has a slope opposite to the high front and low rear slope of the conventional bearing design. In addition, the present invention is a mirror image of the tibial resection surface having a posterior slope, and the lower surface of the bearing has a reverse slope.

The knee joint refers to the joint formed by the three bones surrounding the knee, the femur, tibia, and patella. It corresponds to the key joint involved. When the knee joint does not function properly due to various causes such as degenerative arthritis of the knee and post-traumatic arthritis, as an orthopedic treatment method, an implant that can replace the damaged knee joint is inserted into the patient's bone. is being implemented

1 is a view showing a conventional artificial knee joint, the prior art is disclosed in Korean Patent Registration No. 10-1184905 (September 20, 2012). Hereinafter, it will be described with reference to FIG. 1 .

Total knee arthroplasty is an operation in which a part of the femur (F) and tibia (T) is incised when the knee joint is damaged and an artificial knee joint implant is inserted in the incised area. The artificial knee joint implant implantation surgery is performed in such a way as to fix, fix the tibial element 93 to the proximal portion of the tibia, and position the bearing element 95 between the femoral element 91 and the tibial element 93. will perform

The artificial knee joint bearing element used today is a polyethylene material and is combined with the tibial element 93, which is a substitute for the tibia, and is provided to contact the femoral element 91 so that the femoral element 91 moves on the bearing element 95. At this time, in order to reduce friction between the femoral element 91 and the bearing element 95 and to depict the movement of the human knee while maximizing the joint movement, the upper surface of the bearing element 95 is concave in a downward or distal shape. ) The joint surface is formed, and the lower surface is trimmed flat to be parallel to the ground or perpendicular to the mechanical axis of the tibia (T).

On the other hand, in order to insert the tibia element 93 into the tibia, the tibia is cut flat. In general, during artificial joint surgery, the cutting surface is parallel to the ground to achieve a posterior inclination within about 5 degrees from the ground (average about to have a posterior inclination of 3 degrees). Forming the cutting surface to form a posterior slope of such a gentle angle (high anterior and low posterior) is because it can reduce mechanical wear and increase the stability of the artificial knee joint.

In contrast, as can be seen in FIG. 2 , the human tibial plateau (upper surface) forms a posterior inclination that decreases from the front to the rear at an angle greater than 5 degrees from the ground. Depending on the shape of the tibia, a relatively hard cortical bone (CoT) is located just below the articular surface, and a relatively soft cancellous bone (CaT) is located on the inside. The average posterior inclination of the human tibia before amputation has been studied to be between 7 and 20 degrees, with significant individual differences, and patients in Asia have an average of about 14 degrees. Therefore, if the tibia is cut to have a posterior inclination of about 3 degrees without considering the natural posterior inclination of the tibia, the amount of bone resection on the anterior side becomes excessively large compared to the posterior side, and the relatively hard cortical bone ( CoT) is excised to weaken the bone strength, and postoperative complications or complications such as pain during walking and depression of the artificial knee may be induced. However, there is still no solution to improve the problems that occur in patients with such a large posterior inclination.

Therefore, in the industry, the amount of bone cut is reduced by maximally matching the cutting angle of the tibia to the posterior inclination of the human tibia. It requires artificial knee joint bearing elements with high durability while reproducing natural joint motion.

(Patent Document 1) Korean Patent Publication No. 10-1184905 (2012.09.20.)

The present invention has been devised to solve the above problems,

An object of the present invention is to provide a bearing body having a curved surface shape and a downwardly recessed articular surface so that the artificial knee joint femoral element can slide on the joint surface, extending downward from the bearing body to come into contact with the tibial element However, the overall inclination of the artificial knee joint system including the inclination portion formed to be inclined to at least one side is maintained gently, and the tibia is cut along the patient's own tibial inclination to avoid excessive fractures. Or to provide an artificial knee joint bearing element having a reverse inclination.

An object of the present invention is that the lower inclined portion is formed to have an anterior slope and extends downward from the bearing body from the front to the rear to reduce complications and sequelae after artificial knee arthroplasty and to improve the durability of the artificial knee joint implant. It is to provide an artificial knee joint bearing element having a reverse inclination.

It is an object of the present invention, the load transmitted from the femoral element, including a connecting surface formed between the inclined surface and the inclined surface extending up and down along the periphery of the bearing body and the inclined surface extending rearwardly with a constant inclination of the inclined portion It is to provide an artificial knee joint bearing element having a reverse inclination that stably transmits the incline toward the tibia cut obliquely.

The object of the present invention is applicable to artificial knee joint surgery that forms the tibial cutting surface in the conventional way, and provides an additional angle of extension so that the knee can be stretched better after the artificial joint to a patient with a flexion contracture that does not fully straighten the knee. It is to provide an artificial knee joint bearing element having a reverse inclination.

An object of the present invention is to provide an artificial knee joint bearing element having a reverse inclination in which the connecting surface extends along the outer circumferential surface at the same inclination as the outer circumferential surface and is vertically connected to the inclined surface.

An object of the present invention is that at least a part of the connection surface is bent from one end of the outer peripheral surface to the center side, so that at least a part of the connection surface extends at a different inclination from the outer peripheral surface, so that a bearing element of a relatively large size is provided even on a narrow tibia cutting surface. It is to provide an artificial knee joint bearing element having a reverse slope that can be seated.

An object of the present invention is that the outer circumferential surface includes a front outer circumferential surface constituting the circumference of the bearing body at the front of the bearing body and a rear outer circumferential surface constituting the circumference of the bearing body at the rear of the bearing body, and is connected to the rear outer circumferential surface at the rear end It is to provide an artificial knee joint bearing element having a reverse inclination that is provided so that the vertical length of the surface extending is longer than the vertical length of the front outer circumferential surface at the front end.

The object of the present invention is that the joint surface is defined as the lowest point that is most depressed downward on the anterior and posterior cross section, the first trough having the shortest vertical distance from the articular surface to the lower slope, and the first trough is anterior to the lowest point. It is to provide an artificial knee joint bearing element which is formed on the side and has a reverse inclination to improve durability from loads in the vertical direction.

An object of the present invention is that the front outer peripheral surface and the rear outer peripheral surface extend vertically from the lower surface of the bearing body, and the inclined surface extends rearward with a predetermined inclination with respect to the lower surface of the bearing body and is inclined toward the tibial cutting surface. An object of the present invention is to provide an artificial knee joint bearing element having a reverse inclination in which the bearing element can extend in the direction of the anatomical axis of the tibia.

An object of the present invention is to provide an artificial knee joint bearing element having a reverse inclination extending up and down while having a predetermined angle so that the front outer peripheral surface and the rear outer peripheral surface are perpendicular to the inclined surface.

The present invention is implemented by an embodiment having the following configuration in order to achieve the above object.

According to an embodiment of the present invention, the artificial knee joint bearing element having a reverse inclination according to the present invention has a curved shape and has a downwardly depressed articular surface so that the artificial knee joint femoral element can slide on the joint surface. Body, which is provided to extend downward from the bearing body to be in contact with the tibial element, characterized in that it comprises an inclined portion formed to be inclined to at least one side.

According to another embodiment of the present invention, the lower inclined portion of the artificial knee joint bearing element having a reverse inclination according to the present invention is formed to have an anterior inclination and extends downward from the bearing body from the front to the rear. .

According to another embodiment of the present invention, the inclined portion of the artificial knee joint bearing element having a reverse inclination according to the present invention includes an inclined surface extending backward with a constant inclination, an outer peripheral surface extending up and down along the circumference of the bearing body, and It characterized in that it comprises a connection surface formed between the inclined surfaces.

According to another embodiment of the present invention, the connection surface of the artificial knee joint bearing element having a reverse inclination according to the present invention is characterized in that it extends along the outer circumferential surface at the same inclination as the outer circumferential surface.

According to another embodiment of the present invention, at least a portion of the connecting surface of the artificial knee joint bearing element having a reverse inclination according to the present invention is bent and extended from one end of the outer circumferential surface toward the center so that at least a portion of the connecting surface is inclined different from the outer circumferential surface. characterized in that it is extended to

According to another embodiment of the present invention, the inclination of the lower inclined surface of the artificial knee joint bearing element having a reverse inclination according to the present invention is characterized in that it is 3 degrees or more and 7 degrees or less.

According to another embodiment of the present invention, the outer peripheral surface of the artificial knee joint bearing element having a reverse inclination according to the present invention is the front outer peripheral surface constituting the circumference of the bearing body in front of the bearing body and the bearing body in the rear of the bearing body. It comprises a rear outer peripheral surface constituting the perimeter, and characterized in that the vertical length extending the rear outer peripheral surface and the connecting surface at the rear end is longer than the vertical length extending the front outer peripheral surface at the front end.

According to another embodiment of the present invention, the joint surface of the artificial knee joint bearing element having a reverse inclination according to the present invention has the lowest point most depressed downward on the anterior and posterior cross section, and the vertical distance from the joint surface surface to the lower slope is the most A short first low is defined, and the first low is characterized in that it is formed in front of the lowest point.

According to another embodiment of the present invention, the front outer peripheral surface and the rear outer peripheral surface of the artificial knee joint bearing element having a reverse inclination according to the present invention is characterized in that it extends up and down while having a predetermined angle to be perpendicular to the inclined surface.

According to another embodiment of the present invention, an artificial knee joint bearing with a reverse inclination according to the present invention

The present invention can obtain the following effects by the configuration, combination, and use relationship described below with the present embodiment.

The present invention provides a bearing body having a curved shape and a downwardly recessed articular surface so that the artificial knee joint femur element can slide on the joint surface, extending downward from the bearing body to come into contact with the tibial element, The overall inclination of the artificial knee joint system, including the inclined portion formed to be inclined to at least one side, is maintained gently, but the tibia is cut along the patient's own tibial inclination to avoid excessive fractures. There is an effect of providing an artificial knee joint bearing element.

In the present invention, the inclined portion extends downward from the bearing body from the front to the rear to reduce complications such as depression of the prosthesis and pain during walking after artificial knee arthroplasty, and improve the durability of the artificial knee joint insert.

In the present invention, the inclined portion includes a connecting surface formed between the inclined surface and the outer peripheral surface extending up and down along the periphery of the bearing body and the inclined surface extending while having a constant inclination to the rear, the load transmitted from the femoral element to be inclined. It has the effect of stably delivering to the cut tibia.

The present invention provides an additional angle of extension so that the knee can be extended better after the artificial joint to a patient with a flexion contracture in which the knee is not fully extended even for an artificial knee joint procedure that forms a tibial cutting surface in the conventional way. It can have the effect of providing an artificial knee joint bearing element with an inclination.

In the present invention, at least a portion of the connection surface is bent from one end of the outer circumferential surface to the center side, so that at least a portion of the connection surface is extended at a different inclination from the outer circumferential surface, so that a bearing element of a relatively large size can be seated even on a narrow tibia cutting surface. can

In the present invention, the outer circumferential surface includes a front outer circumferential surface constituting the circumference of the bearing body at the front of the bearing body and a rear outer circumferential surface constituting the circumference of the bearing body at the rear of the bearing body, and the rear outer circumferential surface and the connecting surface at the rear end are It is possible to provide an artificial knee joint bearing element having a reverse inclination provided so that the extended vertical length is longer than the extended vertical length of the front outer circumferential surface at the front end.

In the present invention, the joint surface is defined as the lowest point that is most depressed downward on the anterior and posterior cross section, and the first low point with the shortest vertical distance from the joint surface surface to the lower slope, and the first low point is on the front side of the lowest point. It has the effect of improving durability from a load in the vertical direction.

In the present invention, the front outer circumferential surface and the rear outer circumferential surface extend vertically from the lower surface of the bearing body, and the inclined surface extends rearward with a predetermined inclination with respect to the lower surface of the bearing body. The effect of extending in the direction of the anatomical axis of the tibia can be obtained.

In the present invention, when the tibia is excised between 0 and 5 degrees in the conventional way and the knee does not fully straighten when the existing bearing is inserted (if the flexion contracture remains), an additional extension angle can be obtained using this bearing. . This is an effect due to the design of the bearing element having a relatively thicker back than the front.

1 is a view showing a conventional artificial knee joint

Figure 2 is a view briefly showing the femur and tibia of a patient before performing knee arthroplasty;

3 is a perspective view of an artificial knee joint bearing element 1 having a reverse inclination according to a preferred embodiment of the present invention.

4 is a cross-sectional view A-A' of the artificial knee joint bearing element 1 having a reverse inclination according to an embodiment of the present invention.

5 is a front view of the artificial knee joint bearing element 1 and the femur element 91 provided on the upper side of the bearing element according to an embodiment of the present invention.

6 is a view showing that the artificial knee joint bearing element (1) having a reverse inclination according to an embodiment of the present invention is seated on the tibia (T) together with the tibial element (93)

7 is a cross-sectional view of an artificial knee joint bearing element 1 having a reverse inclination according to another embodiment of the present invention.

8 is a view showing the cutting angle of the tibia when the artificial knee joint bearing element 1 having a reverse inclination according to a preferred embodiment of the present invention is applied.

9 is a cross-sectional view of an artificial knee joint bearing element 1 having a reverse inclination according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the artificial knee joint bearing element having a reverse inclination according to the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, if it is determined that a detailed description of a well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. Unless otherwise defined, all terms in this specification have the same general meaning as understood by those of ordinary skill in the art to which the present invention belongs, and in case of conflict with the meaning of the terms used in this specification, the According to the definition used in the specification.

Throughout the specification, when a part "includes" a certain component, it does not exclude other components unless otherwise stated, and it means that other components may also be further included, The described terms such as “~ unit” mean a unit that processes at least one function or operation. In addition, when it is said to be "connected" between certain components, it is not limited to being fastened in direct contact with each other, but includes fastening through other components, and can transmit a predetermined force or energy even if it is not fastened. It may mean that it is placed so that Hereinafter, the present invention will be described in detail by describing preferred embodiments of the present invention with reference to the accompanying drawings.

Since the present invention is inserted into a human knee joint to reproduce the movement of the knee joint, as shown in FIG. 3 , anterior (Anterior), posterior (Posterior), medial (Medial), lateral (Lateral), and proximal (Proximal) , the distal direction is defined, and with reference to this, the artificial knee joint bearing element 1 having a reverse inclination according to the present invention will be described. The proximal and distal sides may be described as superior and inferior.

3 is a perspective view of an artificial knee joint bearing element 1 having a reverse inclination according to a preferred embodiment of the present invention. The artificial knee joint bearing element 1 having the reverse inclination maintains the inclination of the overall articular surface of the artificial knee joint system as gently as in the conventional invention, but cuts the tibia along the patient's own tibialis inclination to remove excess fractures. It is characterized in that it reduces the complications and sequelae after knee arthroplasty and improves the durability of the artificial knee joint implant by making it possible to avoid it. The artificial knee joint bearing element 1 may be seated or fixed on the tibia in combination with a tibial element 93 to be described later inserted into the tibia. The artificial knee joint bearing element (1) having a reverse inclination includes a bearing body (10), a post (30) and an inclined portion (50).

4 is a cross-sectional view A-A' of the inner portion of the artificial knee joint bearing element 1 having a reverse inclination according to an embodiment of the present invention. 3 and 4 , the bearing body 10 is provided so that the artificial knee joint femur element can slide on the bearing body 10 . As the condyle of the femoral element moves in contact with the bearing body 10, it is possible to reproduce the bending motion of the knee joint. As can be seen in FIG. 4 , the bearing body 10 may be distinguished from the inclined portion 50 to be described later by using a horizontal plane H extending forward and backward, that is, a plane parallel to the ground as a boundary. The bearing body 10 may be formed to have a different height for each section while having a planar shape similar to that of the tibia. The bearing body 10 may have a front side portion higher than a rear side portion, which will be described later. The bearing body 10 includes an articular surface 11 and an outer peripheral surface 13 .

The articular surface 11 is configured to be in contact with the femoral element and the condyle on the upper surface, that is, the proximal side of the bearing body 10 so that the femoral element can reproduce joint motion on the joint surface 11 . The joint surface 11 may have a concave shape by being recessed downward while having a curved shape. As can be seen in FIG. 5, the femoral element 91 is divided into medial and lateral and has a condyle 911 convexly protruding in the downward direction, wherein the condyle 911 is It comes into contact with the articular surface 11 to enable joint movement so that the femoral element 91 can rotate and slide on the joint surface 11 . The sliding motion means that the femoral element 91 slides in the anterior or posterior direction on the articular surface 11, and the meaning of sliding is not limited to only the translational movement of the femoral element 91. It is preferable to interpret including that a predetermined rotational motion may be accompanied together. In addition, the shape of the joint surface 11, which will be described later, may be formed asymmetrically from the inside and the outside in order to vary the rate at which rotation and sliding motion occur.

The curvature of the articular surface 11 may be formed so as not to correspond to the curvature of the condyle 911 of the femoral element, which adjusts the rate at which the femoral element 91 rotates and slides on the articular surface 11. This is to reproduce the actual bending and extension of the knee.

Referring back to FIG. 4 , the bearing body 10 has the anterior portion of the articular surface 11 higher than the posterior portion in order to reproduce natural knee motion and prevent dislocation, so that when going from the front to the rear, a predetermined degree It may have a rear slope that slopes downward. However, as the joint surface 11 is formed to have a concave shape, it may have a shape that rises from the front to the rear in a predetermined section. In detail, from the lowest point 111 to be described later to the rear end of the articular surface 11, the articular surface may be formed in a form that rises toward the rear. In FIG. 3, the articular surface 11 is formed to have a concave shape from the inside and the outside, but in another embodiment of the present invention, the sliding motion predominantly occurs in the lateral part of the knee joint, and the medial part In this case, the medial pivot can be implemented by making the rotational movement dominant. In this case, the outer articular surface can be formed relatively flat compared to the inner one. The articular surface 11 includes a lowest point 111 and a first low point 113 .

Referring to FIG. 6 , the lowest point 111 refers to the lowest point among the articular surfaces when the joint surface 11 of the bearing body 10 is cut into a cross section extending forward and backward, and in the articular surface 11 . It is used as a meaning to refer to the lowest point among the parts recessed downward. The lowest point is a point defined on a cross-section extending forward and backward, and when the bearing element is viewed from a cross-section other than the A-A' cross-section, the position of the lowest point may be changed forward or backward by a predetermined degree. As shown in FIG. 3, as the degree and curvature of the articular surface 11 are different from the inside to the outside of the bearing element 1, the lowest point is the innermost or distal side recessed in the entire articular surface 11. It may mean a specific point on the outside, but it is preferable to see it as the lowest point on a cross-section extending forward and backward, such as A-A' cross-section. The lowest point 111 may have a first length t1 as a vertical distance or vertical distance from the proximal side to the distal side from the inclined surface 51 to be described later, that is, a distance along the mechanical and/or anatomical axis of the tibia. . This will be described later in comparison with the first low point 113 .

The first low point 113 may be defined as a point having the shortest vertical distance from the articular surface to the lower inclined surface. The first trough 113 is a point defined on a cross-section extending forward and backward. have.

As the bearing element 1 replaces a person's knee joint, a load is applied, and thus wear or breakage may occur. The Korea Food and Drug Administration (KFDA) measures the durability of implants through wear tests, etc. and stipulates the minimum thickness of the artificial knee joint. The first low point 113 is defined as a point where the vertical distance to the lower slope is the shortest as shown in FIG. 6, and is formed to have a thickness of a predetermined degree or more, which is more than a predetermined regulation. The first trough 113 has a second distance t2 as a vertical distance or vertical distance from the proximal side to the distal side with the inclined surface 51 to be described later, that is, a distance along the mechanical and/or anatomical axis of the tibia. can

The first low point 113 may be formed in front of the lowest point 111 . The lowest point 111 on the articular surface 11 is the most depressed, but the inclined surface 51 has a constant inclination and extends distally or downward from the front to the rear, in the part where the inclination of the articular surface 11 becomes gentle. A point with the shortest vertical distance to the inclined surface may be defined. At this time, in a loading environment in which the load acts in the vertical direction, that is, in the anatomical axis direction of the tibia, the load due to the load is most applied to the lowest point 111 . In the present invention, the first low point 113 is located in front of the lowest point 111 so that the first distance t1 from the lowest point 111 to the lower and/or distal slope 51 is the first low point 113 . ) to be greater than the second distance t2, which is the vertical distance from the inclined surface 51, so that the thickness of the portion where wear occurs the most is the same as that of the conventional implant, while the thickness of the front part can be made thinner than in the prior art Even with a thinner thickness, safety and durability against load can be maintained.

The outer peripheral surface 13 is provided extending up and down along the circumference of the bearing body 10 . 3 to 6 , the outer circumferential surface 13 surrounds the side surface of the bearing body 10 while having a curved shape. The outer circumferential surface 13 may be formed to extend in a streamlined shape over the circumference of the front, side, and rear portions of the bearing body 10 . The length in which the outer circumferential surface 13 extends vertically may have a predetermined difference for each part. When the bearing element 1 shown in FIG. 5 is viewed from the front side, the front end of the bearing body 10 may convexly protrude upward, so that the outer peripheral surface 13 of the front side may extend higher than other parts. . In addition, when the bearing body 10 as a whole has a higher shape than the rear as in FIG. 4 , the outer peripheral surface of the rear side may extend lower than the outer peripheral surface of the front side. The outer peripheral surface 13 includes a front outer peripheral surface 131 , a lateral outer peripheral surface 133 , and a rear outer peripheral surface 135 . In a preferred embodiment of the present invention, the outer circumferential surface 13 may extend vertically along the anatomical axis of the tibia, but as in other embodiments of the present invention, the right to extend while forming a predetermined angle with the anatomical axis of the tibia not excluded from the scope.

The front outer circumferential surface 131 constitutes a circumference of the bearing body in front of the bearing body and extends vertically while having a predetermined length. The anterior outer circumferential surface 131 may extend vertically parallel to the anatomical axis of the tibia (T) as in the preferred embodiment of the present invention shown in FIG. 6, and another embodiment of the present invention shown in FIG. As in the example, it may extend up and down while having a predetermined angle with the anatomical axis of the tibia (T). With respect to the front outer circumferential surface 131, a first vertical length h1 of the front outer circumferential surface 131 along the anatomical axis direction of the tibia may be defined. The length in which the front outer circumferential surface 131 extends vertically is changed as going from the inside to the outside of the bearing element 1 , and the first vertical length h1 is the position of the front and rear cross-sections of the bearing element 1 . may vary depending on

The lateral outer peripheral surface 133 extends up and down while constituting the circumference of the bearing body from the side of the bearing body 10 . The lateral outer circumferential surface 133 extends while forming a curved surface on the inside and outside of the bearing body, and the length of the extension may vary depending on the location. The lateral outer peripheral surface 133 may be provided on the side of the bearing body 10 to connect the front outer peripheral surface 131 and the rear outer peripheral surface 135 to be described later.

The rear outer peripheral surface 135 extends up and down while constituting the circumference of the bearing body at the rear of the bearing body 10 . The rear outer circumferential surface 135 may extend vertically parallel to the anatomical axis of the tibia (T), and as in another embodiment of the present invention shown in FIG. It can extend up and down while having an angle of . Since the rear height of the bearing body 10 may vary as it goes from the inside to the outside of the bearing element 1 , the length in which the rear outer circumferential surface 135 extends up and down is at the position of the front and rear end surfaces of the bearing element 1 . may vary depending on

The lower surface 15 is a part constituting the distal plane of the bearing body 10 along the horizontal plane H extending forward and backward, and is a plane serving as a reference for the extending direction of the outer peripheral surface 13 . In a preferred embodiment of the present invention, the outer circumferential surface 13 may extend vertically from the lower surface 15 . The lower surface may be provided or defined substantially parallel to the horizontal plane H. It may be substantially the same as the upper surface of the inclined portion 50 . As the bearing body 10 and the inclined portion 50 are integrally provided, the lower surface 15 may not be exposed to the outside or may be omitted.

In another embodiment of the present invention shown in FIG. 7 , the anterior outer circumferential surface 131 and/or the rear outer circumferential surface 135 extend vertically while having a predetermined angle with the anatomical axis of the tibia (T) in a horizontal plane. It can also be defined as extending from (H) while having a predetermined angle that is not a right angle. At this time, the inclined surface 51 to be described later has a predetermined inclination α with respect to the horizontal plane H, and the front outer peripheral surface 131 and/or the rear outer peripheral surface 135 may extend while forming a preferably perpendicular to the inclined surface. . At this time, the position of the joint surface 111 and the post 30 may be formed relatively rearward.

Referring back to FIGS. 3 to 6 , the post 30 replaces the posterior cruciate ligament to prevent posterior dislocation when the artificial knee joint is bent, and may be provided for natural knee movement (femoral roll back phenomenon). The post 30 protrudes upward or proximally from the bearing body 10 and engages the femoral element 91 to reproduce the knee motion through the post-cam motion. Similarly in an anterior stabilized (AS) or ultra congruence (UC) type in which a post is not present while removing the posterior cruciate ligament, in another embodiment of the present invention, the bearing body 10 without the post 30 is provided. ) and the inclined portion 50 to be described later may be provided to reproduce the knee motion of the artificial knee joint.

The inclined portion 50 extends downward from the bearing body 10 and is provided to contact the tibial element, and is formed to extend downward from the bearing body toward at least one side, preferably from the front to the rear. The inclined surface corresponding to may have a forward inclination. The inclined portion 50 may be distinguished from the bearing body 10 on the basis of a horizontal plane (H) extending forward and backward, that is, a plane parallel to the ground, but preferably extends integrally from the bearing body (10). can be formed. As the inclined portion 50 is provided with a predetermined inclination at the lower side of the bearing body 10, the surgeon cuts the patient's tibia in a direction parallel to the ground or close to perpendicular to the anatomical axis of the tibia. Since the cutting surface of the tibia can be resected to have a slope close to the posterior inclination of the patient's tibia, the anterior portion can be cut less. In addition, it is possible to form a tibia cutting surface by cutting the anterior cortical bone (CoT) portion that was excessively cut relatively less, thereby improving the stability and durability of the knee joint after surgery. In particular, in the case of an Asian population having a posterior inclination of 10 degrees or more, preferably about 14 degrees, it is possible to reproduce the patient's unique knee joint. The inclined portion 50 includes an inclined surface 51 and a connecting surface 53 .

The inclined surface 51 may be provided so as to extend while having an anterior inclination in contact with the tibial element. As can be seen in FIGS. 4 and 6 , the inclined surface may be extended with a predetermined inclination α toward the rear lower side or the front upper side based on the horizontal plane H extending forward and backward. In a preferred embodiment of the present invention, the inclined surface 51 may be inclined forward while having a certain inclination, and the inclination α may be 3 to 7 degrees. Here, the 'anterior slope' is defined as a shape in which the inclined surface 51 rises upward or proximal toward the front, and corresponds to a 'posterior slope' having a shape in which the cutting surface of the tibia descends downward or distally toward the rear. can be used as a concept. The inclination α is preferably a vertical length h2 at which the rear outer circumferential surface 135 and the connecting surface 53 extend at the rear end of the bearing element rather than the vertical length h1 at which the front outer circumferential surface 131 extends at the front end. The number can be limited so that is longer (h2>h1). However, when the inclination α of the lower surface is formed to be small and the length of the connection surface 53 to be described later is small, the vertical length h1 at the front end may be formed to be longer than the vertical length h2 at the rear end. (h1>h2). Referring to FIG. 5 , the inclined surface 51 may have the same plane as the bearing body 10 when the inclined surface is orthogonally projected with respect to the horizontal plane H extending forward and backward.

Referring to FIG. 8 , when the bearing element according to an embodiment of the present invention is applied, as the inclined surface 51 is provided, the cutting surface during cutting of the tibia descends distally toward the rear, that is, to have a rear inclination. can be formed Unlike the conventional cutting surface that is cut to achieve a posterior inclination within about 3 degrees from the ground from an angle parallel to the ground, the cutting angle (β) of the tibial cutting surface is obtained by adding the inclination (α) of the inclined surface 51 to the horizontal plane (H ) from 3 degrees to 12 degrees. Furthermore, C shown by a dotted line in FIG. 8 corresponds to the cutting surface of the tibia when the conventional bearing element is used. As the inclined surface 51 is provided, it can be seen that the front portion of the tibia is less cut. Accordingly, when the inclined surface 51 is placed parallel to the ground, the joint surface 11 is formed due to the overall shape in which the front part of the artificial knee joint bearing element having a reverse inclination according to the present invention is thin and the rear part is relatively thick. The upper surface may have a forward slope.

In addition, since the inclination α of the inclined surface 51 has an anterior slope of 3 to 7 degrees, an additional extension interval is provided so that the knee can be stretched better after the artificial joint to a patient with a flexion contracture that does not fully extend the knee do. Because the front portion of the bearing element according to the present invention has a relatively thin shape compared to the rear portion, the extension interval is widened when the knee is unfolded, which additionally provides a space where the knee can be further stretched so that normal knee movement is possible. do.

The connection surface 53 may be provided between the outer peripheral surface 13 extending vertically along the circumference of the bearing body 10 and the inclined surface 51 to connect the outer peripheral surface 13 and the inclined surface 51 . . The connecting surface 53 may preferably be formed between the lateral connecting surface 133 and/or the rear connecting surface 135 and the inclined surface 51 . In a preferred embodiment of the present invention, the connection surface 53 may extend along the outer circumferential surface at the same inclination as the outer circumferential surface. As in FIG. 6 , when the rear outer circumferential surface 135 extends substantially vertically while forming a right angle with the horizontal plane H, the connection surface 53 is inclined from the rear outer circumferential surface 135 to the rear outer circumferential surface 135 at the same inclination. It may extend and be connected to the inclined surface 51 . In another embodiment of the present invention, at least a portion of the connecting surface 53 is extended at a different inclination from the outer circumferential surface 13 by bending and extending from one end of the outer circumferential surface toward the center, as shown in FIG. 9, and may be connected to the inclined surface 51. . In this case, a relatively large bearing element can come into contact with the narrow tibial cutting surface and the tibial element, so that artificial knee replacement surgery suitable for a patient who needs a large bearing element (1) compared to the tibial cutting surface can be performed.

As can be seen in FIG. 6 , the rear outer peripheral surface 135 and the connecting surface 53 may define a second vertical length h2 according to the anatomical axis direction of the tibia. The length in which the rear outer circumferential surface 135 and the connecting surface 53 extend vertically is changed as going from the inside to the outside of the bearing element 1 , and the second vertical length h2 is the bearing element 1 . ) may vary depending on the position of the front and rear cross-sections.

In this case, the second vertical length h2 may be longer than the first vertical length h1. In the bearing element 1 according to the present invention, the bearing body 10 as a whole has a higher shape in the front than the rear, but as the connection surface 53 extends from the rear, the connection surface 53 on the lower side of the rear outer circumferential surface 135 ) is provided so that the second vertical length h2 in which the rear outer peripheral surface 135 and the connecting surface 53 extend vertically is longer than the first vertical length h1 in which the front outer peripheral surface 131 extends vertically. . In FIG. 6, with respect to the A-A' section of the inner (media) of the front outer circumferential surface, the vertical length h2 in which the rear outer circumferential surface and the connection surface extend is longer than the vertical length h1 in which the front outer circumferential surface extends. It is preferable not only on the inside of the bearing element 1 but also on the outside. In another embodiment of the present invention, when the length in which the connecting surface 53 is extended is short due to the small inclination of the inclined surface 51, the front outer peripheral surface 131 of the bearing body 10 as a whole has a higher shape than the rear. The first vertical length h1 extending vertically may be formed to be longer than the second vertical length h2 extending vertically between the rear outer circumferential surface 135 and the connection surface 53 .

The artificial knee joint bearing element 1 of the present invention may be combined with the tibial element 93 inserted into the tibia after cutting the tibia. Preferably, the inclined surface 51 of the artificial knee joint bearing element 1 is combined with the tibial element 93, and as the inclined surface 51 is formed with an anterior inclination, the tibial element is also downward from the front to the rear, that is, It may be formed with a distally descending slope. The tibial element 93 may have an inner wall having a predetermined thickness extending upward or proximal from the outer circumferential surface, and the inner wall and the lower surface of the inclined portion 50 may be coupled through a taper coupling, an interference fit coupling, or the like. In this case, the inner wall extending proximally from the tibial element 93 may be formed to extend with a shape and an angle corresponding to the shape of the outer peripheral surface 13 and the connection surface 53 of the artificial knee joint bearing element 1 .

The above detailed description is illustrative of the present invention. In addition, the above description shows and describes preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications are possible within the scope of the concept of the invention disclosed herein, the scope equivalent to the written disclosure, and/or within the scope of skill or knowledge in the art. The written embodiment describes the best state for implementing the technical idea of the present invention, and various changes required in specific application fields and uses of the present invention are possible. Accordingly, the detailed description of the present invention is not intended to limit the present invention to the disclosed embodiments. Also, the appended claims should be construed as including other embodiments.

Claims

In the artificial knee joint implant,

A bearing body having a curved shape and having a downwardly recessed articular surface so that the artificial knee joint femur element can slide on the articular surface;

An artificial knee joint bearing element extending downward from the bearing body and provided to come in contact with the tibial element, the artificial knee joint bearing element having a reverse inclination including an inclined portion formed to be inclined to at least one side.
The artificial knee joint bearing element having a reverse inclination according to claim 1, wherein the inclined portion extends downward from the bearing body from the front to the rear.
The inclined surface according to claim 2, wherein the inclined portion extends from the bearing body rearward with a constant inclination to form a front inclination;

An artificial knee joint bearing element having a reverse inclination, characterized in that it includes a connection surface formed between an outer peripheral surface extending up and down along the circumference of the bearing body and the inclined surface.
[4] The artificial knee joint bearing element of claim 3, wherein the connecting surface extends along the outer circumferential surface at the same inclination as the outer circumferential surface.
[4] The artificial knee joint bearing element of claim 3, wherein at least a portion of the connection surface is bent from one end of the outer circumferential surface toward the center, so that at least a portion of the connection surface extends at a different inclination from the outer circumferential surface.
The artificial knee joint bearing element having a reverse inclination according to claim 3, wherein the inclination of the inclined surface is 3 degrees or more and 7 degrees or less.
According to any one of claims 3 to 6, wherein the outer circumferential surface comprises a front outer circumferential surface constituting the circumference of the bearing body at the front of the bearing body and a rear outer circumferential surface constituting the circumference of the bearing body at the rear of the bearing body, ,

An artificial knee joint bearing element having a reverse inclination, characterized in that the vertical length at which the rear outer circumferential surface and the connecting surface at the rear end extend is longer than the vertical length at which the front outer circumferential surface at the front end extends.
The method of claim 7, wherein the articular surface is defined as the lowest point most depressed downward on the anterior and posterior cross section, the first trough with the shortest vertical distance from the articular surface to the lower slope,

The first low point is an artificial knee joint bearing element having a reverse slope, characterized in that formed on the front side than the lowest point.
According to claim 7, wherein the front outer peripheral surface and the rear outer peripheral surface extends vertically from the lower surface of the bearing body, and the inclined surface extends rearward with a predetermined inclination with respect to the lower surface of the bearing body. artificial knee joint bearing elements.
The artificial knee joint bearing element having a reverse inclination according to claim 7, wherein the front outer peripheral surface and the rear outer peripheral surface extend up and down while having a predetermined angle to be perpendicular to the inclined surface.
[4] The artificial knee joint bearing element having a reverse inclination according to claim 3, wherein the bearing body and the inclined portion are integrally formed.