Knee prosthesis structure capable of preserving anterior and posterior cruciate ligaments

Abstract

The present invention discloses a knee joint prosthesis structure capable of retaining anterior and posterior cruciate ligaments, comprising a femoral prosthesis, a pad, a tibial prosthesis and a patellar prosthesis, wherein the femoral prosthesis is provided with two arc-shaped brackets, a first channel is formed between the two brackets, two pads are provided, a support surface is provided at the upper end of the pad, a second channel is formed between the two pads, and the tibial prosthesis is provided with two base blocks, a connecting column is provided at the lower end of the base block, and a third channel is formed between the two base blocks. The present invention provides the femoral prosthesis, the pad and the tibial prosthesis with a first channel, a second channel and a third channel corresponding to each other, respectively, so that the anterior and posterior cruciate ligaments between the femur and the tibia can move freely in the space of the first channel, the second channel and the third channel, thereby retaining the anterior and posterior cruciate ligaments of the original knee joint, retaining all the bone of the femoral intercondylar spine and the tibial intercondylar spine, improving the stability, proprioception and spatial position sense of the patient's knee joint after surgery, restoring the patient's function of going up and down stairs and squatting, achieving normal leg flexion and extension movement, and improving patient satisfaction.

Description

Technical Field

[0001] The invention relates to the technical field of joint surgical instruments, and in particular to a knee joint prosthesis structure capable of retaining anterior and posterior cruciate ligaments. Background Art

[0002] During total knee replacement surgery, a knife is used to remove the bone of the distal femur and proximal tibia and the surrounding soft tissue, and then a knee prosthesis is installed. Knee prostheses usually include femoral prostheses, pads, tibial prostheses, and patellar prostheses. The current knee prosthesis structure has two major types: PS and CR prostheses, but they do not reserve a place for the anterior cruciate ligament to pass through, so they cannot retain the original anterior cruciate ligament of the knee joint, resulting in partial loss of proprioception of the knee joint after surgery, affecting the function of the patient's knee joint, causing about 20% of patients to complain about poor knee replacement results, especially poor feeling and function when going up and down stairs and squatting. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a knee joint prosthesis structure that can retain the anterior and posterior cruciate ligaments, which can retain all the normal bones of the anterior and posterior cruciate ligaments, the intercondylar spines of the femur and the intercondylar spines of the tibia, and the prosthesis has lower restrictions, so that the patient's knee joint stability and proprioception are better after surgery, the function is better restored, and normal leg flexion and extension movements can be achieved, the patient's spatial position sense during knee joint activities is improved, and the patient's satisfaction is improved.

[0004] According to the first aspect of the present invention, a knee joint prosthesis structure capable of retaining anterior and posterior cruciate ligaments comprises: a femoral prosthesis, wherein the femoral prosthesis is provided with two arc-shaped brackets, a first channel is formed between the two brackets, and the brackets are provided with positioning columns; two pads, wherein the two pads are respectively arranged in one-to-one correspondence with the two brackets, a second channel corresponding to the first channel is formed between the two pads, an upper end of the pad is provided with a concave support surface, and an outer surface of the bracket is provided with a bracket convex surface matching the support surface; A bone prosthesis, comprising two base blocks corresponding to the two pads one by one, the pads abutting against the base blocks, a connecting column being provided at the lower end of the base block, a third channel corresponding to the second channel being formed between the two base blocks, and the two base blocks being connected by a connecting piece; a patella prosthesis, wherein the patella prosthesis is located in front of the femoral prosthesis, one end of the patella prosthesis protrudes outward to form an inner side surface and an outer side surface, a protrusion being formed between the inner side surface and the outer side surface, and a mounting base being provided at the other end of the patella prosthesis.

[0005] The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to the embodiment of the present invention has at least the following beneficial effects: by respectively providing the femoral prosthesis, the pad and the tibial prosthesis with the first channel, the second channel and the third channel corresponding to each other, the anterior and posterior cruciate ligaments between the femur and the tibia can move freely in the space of the first channel, the second channel and the third channel, so that all normal bones of the anterior and posterior cruciate ligaments, the intercondylar spines of the femur and the intercondylar spines of the tibia can be retained, the patient's knee joint stability, proprioception and spatial position sense after surgery are improved, the patient's ability to go up and down stairs and squat is restored, normal leg flexion and extension movements are achieved, and patient satisfaction is improved.

[0006] According to some embodiments of the present invention, a plurality of positioning posts are provided, and the plurality of positioning posts are distributed vertically and spaced apart along the inner wall of the bracket.

[0007] According to some embodiments of the present invention, the outer edge of the bracket is provided with an inwardly bent flange.

[0008] According to some embodiments of the present invention, a downwardly extending clamping platform is provided at the lower end of the cushion block, and a clamping slot cooperating with the clamping platform is provided at the upper end of the base block, and the clamping platform is accommodated in the clamping slot.

[0009] According to some embodiments of the present invention, the two cushion blocks are respectively a first cushion block and a second cushion block, and the inner and outer diameters, front and rear diameters and curvatures of the first cushion block and the second cushion block are different.

[0010] According to some embodiments of the present invention, the lateral side surface is larger than the medial side surface, and the protrusion is located in the middle of one end of the patella prosthesis close to the medial side surface.

[0011] According to some embodiments of the present invention, three mounting bases are provided, and the three mounting bases are distributed circumferentially at 120°.

[0012] According to some embodiments of the present invention, a plurality of first reinforcing ribs are disposed on the outer wall of the positioning column.

[0013] According to some embodiments of the present invention, a plurality of second reinforcing ribs are disposed on the outer wall of the connecting column.

[0014] According to some embodiments of the present invention, both ends of the connecting member are respectively connected and fixed to the front ends of the two base blocks by fasteners; or the connecting member is provided with two, and the two connecting members are connected between the side surfaces of the two base blocks close to each other by interbone drilling.

[0015] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0017] Figure 1 A schematic diagram of the three-dimensional structure of a knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of the three-dimensional structure of a femoral prosthesis;

[0019] Figure 3 is the posterior view of the femoral prosthesis;

[0020] Figure 4 It is a schematic diagram of the assembly of the spacer and the tibial prosthesis when a fixed platform knee prosthesis is used;

[0021] Figure 5 It is a schematic diagram of the assembly of the pad and the tibial prosthesis when a mobile platform knee prosthesis is used;

[0022] Figure 6 is a bottom view of the base block;

[0023] Figure 7 A view of one end of the patellar prosthesis. DETAILED DESCRIPTION

[0024] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0025] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0026] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0027] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0028] Reference Figures 1 to 7 As shown, a knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to an embodiment of the present invention mainly comprises a femoral prosthesis 100, a tibial prosthesis 300, a patellar prosthesis 400 and two pads 200. Figure 2 and Figure 3 The upper surface of the femoral prosthesis 100 is offset outward at a certain angle so that it can better match the femur of the human body. The femoral prosthesis 100 is provided with two arc-shaped brackets 110, and the brackets 110 are used to wrap and fix on the distal end of the femur and the medial and lateral condyles. The arc-shaped brackets 110 can better wrap the distal end of the femur. A first channel 120 is formed between the two brackets 110. The first channel 120 is in an arc shape. The first channel 120 can facilitate the passage of the anterior and posterior cruciate ligaments. The bracket 110 is provided with a positioning column 130, and the positioning column 130 is used to fix the femoral prosthesis 100 on the femur. The outer wall of the positioning column 130 can be provided with a plurality of first reinforcing ribs, so that the contact surface between the positioning column 130 and the femur is larger, thereby improving the connection strength. For example, the outer wall of the positioning column 130 can be provided with three first reinforcing ribs to form a three-wing column structure.

[0029] There are two pads 200, and the two pads 200 are arranged in one-to-one correspondence with the two brackets 110. The upper end of the pad 200 is provided with a concave support surface 230, and the outer surface of the bracket 110 is provided with a bracket convex surface that matches the support surface. Therefore, the femoral prosthesis 100 can slide or roll relative to the pad 200 through the bracket convex surface. A second channel 220 corresponding to the first channel 120 is formed between the two pads 200, and the second channel 220 can facilitate the passage of the anterior and posterior cruciate ligaments. According to the activity mode of the pad 200, the knee joint prosthesis structure of the present invention has two types: a fixed platform knee joint prosthesis and a movable platform knee joint prosthesis, and the appropriate type can be selected according to actual needs. Figure 4 , the convex surface of the bracket of the fixed platform knee joint prosthesis slides on the support surface 230 of the pad 200, at which time the pad 200 is fixed and cannot move; refer to Figure 5 The convex surface of the bracket of the mobile platform knee joint prosthesis and the supporting surface 230 of the cushion block 200 can slide against each other, and at this time, the cushion block 200 has a certain movable space.

[0030] The tibial prosthesis 300 is provided with two base blocks 310 corresponding to the two pads 200 one by one, and the pads 200 abut against the base blocks 310. When the knee joint prosthesis structure is a movable platform knee joint prosthesis, the pads 200 can move relative to the base blocks 310. When the knee joint prosthesis structure is a fixed platform knee joint prosthesis, the base blocks 310 limit and fix the pads 200. The lower end of the base block 310 is provided with a connecting column 330, and the tibial prosthesis 300 can be fixed to the proximal end of the tibia through the connecting column 330. The outer wall of the connecting column 330 can be provided with a plurality of second reinforcing The ribs are strengthened to increase the contact area between the connecting column 330 and the tibia, thereby enhancing the connection strength. For example, the outer wall of the connecting column 330 may be provided with three second reinforcing ribs to form a three-wing column structure. A third channel 320 corresponding to the second channel 220 is formed between the two base blocks 310. The third channel 320 can facilitate the passage of the anterior and posterior cruciate ligaments. The two base blocks 310 are connected and fixed by a connecting piece 340. The connecting piece 340 can maintain the relative position stability between the two base blocks 310 to prevent the two base blocks 310 from loosening. Specifically, when the knee joint prosthesis structure is a fixed platform knee joint prosthesis, the two ends of the connecting member 340 are respectively connected and fixed to the front ends of the two base blocks 310 by fasteners 341, and the fasteners 341 can be structures such as screws; when the knee joint prosthesis structure is a movable platform knee joint prosthesis, two connecting members 340 are provided, and the two connecting members 340 are connected between the sides of the two base blocks 310 that are close to each other by interbone drilling. The side can protrude upward relative to the base block 310 for easy connection, and at the same time prevent the pad 200 from easily sliding off the base block 310. At this time, the connecting member 340 can be a rod-shaped structure. When the patient's proximal tibia bone condition is very good, the two ends of the connecting member 340 may not be connected and fixed to the front ends of the two base blocks 310 by fasteners 341; or there are two connecting members 340, but the two connecting members 340 may not be connected between the sides of the two base blocks 310 that are close to each other, that is, the prostheses on the left and right sides of the tibia may not be connected.

[0031] Reference Figure 1 and Figure 7 The patella prosthesis 400 is located in front of the femoral prosthesis 100. One end of the patella prosthesis 400 protrudes outward to form an inner side surface 410 and an outer side surface 420. A protrusion 430 is formed between the inner side surface 410 and the outer side surface 420. The other end of the patella prosthesis 400 is provided with a mounting base 440, and the patella prosthesis 400 can be installed and fixed by the mounting base 440.

[0032] The knee prosthesis structure of the present application is provided with a first channel 120, a second channel 220 and a third channel 320 corresponding to each other in the femoral prosthesis 100, the pad 200 and the tibial prosthesis 300 respectively, so that the anterior and posterior cruciate ligaments between the femur and the tibia can move freely in the space of the first channel 120, the second channel 220 and the third channel 320, so that the anterior and posterior cruciate ligaments, the intercondylar femoral spine and the intercondylar tibial spine of the original knee joint can be retained. The restrictiveness of the prosthesis is lower, the stability, proprioception and spatial position sense of the patient's knee joint after surgery are improved, the patient's ability to go up and down stairs and squat is restored, normal leg flexion and extension movements are achieved, and patient satisfaction is improved.

[0033] Reference Figure 2 In some embodiments, a plurality of positioning posts 130 are provided, and the plurality of positioning posts 130 are spaced apart from each other along the inner wall of the bracket 110. For example, each bracket 110 may be provided with three positioning posts 130, wherein the outer diameter of the positioning post 130 in the middle may be larger than the outer diameters of the other positioning posts 130, so that the femoral prosthesis 100 can be more firmly fixed on the femur. Of course, each bracket 110 may also be provided with only one positioning post 130, in which case the positioning post 130 is provided in the middle of the inner wall of the bracket 110.

[0034] In some embodiments, the outer edge of the bracket 110 is provided with an inwardly bent flange 111. During installation, the flange 111 can be fastened to the femur to further improve the stability of the connection.

[0035] Reference Figure 4 In some embodiments, when the knee joint prosthesis structure is a fixed platform knee joint prosthesis, the lower end of the pad 210 is provided with a clamping platform 210 extending downward, and the upper end of the base block 310 is provided with a clamping slot 311 that cooperates with the clamping platform 210, and the clamping platform 210 is accommodated in the clamping slot 311. Through the above arrangement, the pad 200 is fixed on the base block 310 to prevent the pad 200 from moving. Of course, in order to further improve the stability of the pad 200 fixed on the base block 310, the pad 200 can be further fixed to the base block 310 by fasteners such as screws 211.

[0036] Since the sizes of the inner and outer menisci of the human knee joint are usually different, in some embodiments of the present invention, the two pads 200 are respectively a first pad and a second pad, and the inner and outer diameters, the anterior-posterior diameters and the curvatures of the first and second pads are different, so that the sizes of the first pad and the second pad are close to the inner and outer menisci required by the patient, respectively. By adopting bionic design for the two pads, they are more in line with the original structure of the human body, thereby improving the recovery effect of the knee joint function after surgery.

[0037] Reference Figure 7In practice, the lateral surface of the human patella is usually larger than the medial surface of the patella. Therefore, in some embodiments of the present invention, the lateral surface 420 is larger than the medial surface 410, and the protrusion 430 is located in the middle of one end of the patella prosthesis 400 close to the medial surface 410, which is more in line with the actual structure of the human knee joint and improves the postoperative knee joint function recovery effect.

[0038] In some embodiments, three mounting bases 440 are provided, and the three mounting bases 440 are distributed circumferentially at 120° at the bottom of the patellar prosthesis 400. The mounting base 440 is a non-cylindrical structure, which can adopt a three-wing columnar structure similar to the above-mentioned connecting column, so that the installation and fixation are more stable.

[0039] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. A knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments, characterized in that: include: A femoral prosthesis, wherein the femoral prosthesis is provided with two arc-shaped brackets, a first channel is formed between the two brackets, and the brackets are provided with positioning columns; Two cushion blocks, the two cushion blocks are respectively arranged in one-to-one correspondence with the two brackets, a second channel corresponding to the first channel is formed between the two cushion blocks, an inner concave support surface is provided at the upper end of the cushion block, and a bracket convex surface matching the support surface is provided on the outer surface of the bracket; The tibial prosthesis is provided with two base blocks corresponding to the two cushion blocks one by one, the cushion blocks abut against the base blocks, a connecting column is provided at the lower end of the base block, a third channel corresponding to the second channel is formed between the two base blocks, and the two base blocks are connected by a connecting piece; A patella prosthesis, the patella prosthesis is located in front of the femoral prosthesis, one end of the patella prosthesis protrudes outward to form a medial side and a lateral side, a protrusion is formed between the medial side and the lateral side, the other end of the patella prosthesis is provided with a mounting base, the lateral side is larger than the medial side, the protrusion is located in the middle of one end of the patella prosthesis close to the medial side, three mounting bases are provided, and the three mounting bases are distributed 120° circumferentially; When the knee joint prosthesis structure is a movable platform knee joint prosthesis, the pad block is movable relative to the base block; when the knee joint prosthesis structure is a fixed platform knee joint prosthesis, the base block limits and fixes the pad block, and the lower end of the pad block is provided with a downwardly extending clamping platform, and the upper end of the base block is provided with a clamping groove that cooperates with the clamping platform, and the clamping platform is accommodated in the clamping groove.

2. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to claim 1, characterized in that: A plurality of positioning posts are provided, and the plurality of positioning posts are distributed at intervals up and down along the inner wall of the bracket.

3. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to claim 1, characterized in that: The outer edge of the bracket is provided with a flange bent inwardly.

4. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to claim 1, characterized in that: The two cushion blocks are respectively a first cushion block and a second cushion block, and the inner and outer diameters, front and rear diameters and curvatures of the first cushion block and the second cushion block are all different.

5. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to claim 1, characterized in that: The outer wall of the positioning column is provided with a plurality of first reinforcing ribs.

6. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to claim 1, characterized in that: The outer wall of the connecting column is provided with a plurality of second reinforcing ribs.

7. The knee joint prosthesis structure capable of retaining the anterior and posterior cruciate ligaments according to any one of claims 1 to 6, characterized in that: The two ends of the connecting member are respectively connected and fixed to the front ends of the two base blocks by fasteners; or two connecting members are provided, and the two connecting members are connected between the sides of the two base blocks close to each other by interosseous drilling.

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