Bionic unicompartmental prosthesis

Abstract

The invention relates to a bionic unicondylar prosthesis which comprises an inner side pad and an outer side pad, and the inner side pad is configured as a tibial plateau inner side prosthesis of a knee joint; the lateral pad is configured as a tibial plateau lateral prosthesis of the knee joint; wherein the inner side pad and the outer side pad are both provided with tibia anatomical shapes, and the tibia anatomical shapes are determined according to the tibia inner side and the tibia outer side of the knee joint of the human body; a first bionic concave curved surface and a second bionic concave curved surface are respectively arranged at the tops of the inner side pad and the outer side pad; each of the first bionic concave curved surface and the second bionic concave curved surface is provided with four sections of arc-shaped curved surfaces. According to the prosthesis, dislocation of the gasket can be effectively prevented, abrasion between the prostheses is reduced through contact of more articular surfaces, and the service life of the prostheses is prolonged.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of orthopedic medical devices, and in particular relates to a bionic unicompartmental prosthesis. BACKGROUND

[0002] Currently, unicompartmental knee joint prostheses are gaining more attention, and there are mainly two forms for the unicompartmental knee joint: fixed platform and mobile platform. In order to make the distal femur prosthesis move more naturally, the mobile platform spacer is not locked with the proximal tibial prosthesis, and the joint surface is usually designed as a spherical surface, so that the distal femur can rotate in a larger range. The fixed platform spacer is locked with the proximal tibial prosthesis, and the joint surface is usually designed as a flat surface or a large radius curved surface, so that the femoral prosthesis movement does not limit it, and realizes the free movement of the distal femur.

[0003] The mobile platform may have the risk of spacer dislocation, and the fixed platform may have the risk of excessive wear of the joint spacer, and how to reduce wear and prolong service life is a technical problem that needs to be solved. For example, in the prior art, there is a product that uses a spacer fixed with a tibial tray, and a buckle is provided on the spacer to fix the tibial tray; however, the spacer and the tray of this product are only fixed by a single buckle, and the spacer and the tibial tray are prone to sliding, which increases the wear of the spacer. For another example, in the prior art, there is another product that directly fixes the spacer on the tibial section by bone cement, and the lower part of the spacer is provided with a long strip-shaped protruding structure, which can be inserted into the slot on the tibial section; however, the spacer of this structure adopts a single slot fixing form, and the stress is mainly concentrated on the protruding structure, which is easy to loosen for long-term effect, and is not fixed firmly, which not only increases the wear, but also reduces the service life of the spacer. SUMMARY

[0004] In view of the above analysis, the embodiments of the present application aim to provide a bionic unicompartmental prosthesis to solve one or more of the above problems in the prior art.

[0005] The purpose of the present application is achieved as follows:

[0006] A bionic unicompartmental prosthesis, comprising a tibial pad, the tibial pad having:

[0007] a medial pad configured as a tibial plateau medial prosthesis of a knee joint;

[0008] The outer side pad is configured as a tibial platform prosthesis of the knee joint; wherein the inner side pad and the outer side pad both have a single condyle anatomical shape determined according to the medial tibial plateau and the lateral tibial plateau of the human knee joint; the top part of the inner side pad and the outer side pad has a first bionic concave surface and a second bionic concave surface respectively; the first bionic concave surface and the second bionic concave surface both have four arc surfaces.

[0009] Further, the inner side pad and the outer side pad are fixedly installed on the tibial bone cutting surface by using bone cement.

[0010] Further, the bottom surface of the inner side pad and the outer side pad is convexly provided with an insertion type locking structure which can be inserted into the insertion slot on the tibial bone cutting surface.

[0011] Further, the insertion type locking structure has a long wing, a short wing and a column, the length of the long wing is greater than the length of the short wing, the long wing is arranged vertically to the short wing, and the column is arranged in the area surrounded by the long wing and the short wing; wherein the length direction of the long wing is arranged along the x-axis direction, and the length direction of the short wing is arranged along the y-axis direction; the x-axis direction refers to the direction of the front of the human body, and the y-axis direction refers to the direction of the side of the human body, which is perpendicular to the x-axis direction.

[0012] Further, the column and the short wing have a symmetry plane which is parallel to the long wing.

[0013] Further, the long wing, the short wing and the column have the same height, the length of the short wing is 1 / 4-1 / 3 of the length of the long wing, and the vertical distance between the axis of the column and the long wing is 7-10 mm.

[0014] Further, the side wall surface of the long wing is provided with a first lateral groove and a second lateral groove arranged in parallel from top to bottom, the short wing is provided with a third lateral groove, and the side surface of the column is provided with an annular groove; wherein the distance between the first lateral groove, the second lateral groove, the third lateral groove and the annular groove and the bottom surface of the inner side pad and the outer side pad is 6-8 mm, 2-4 mm, 3-4 mm and 3-4 mm respectively.

[0015] Further, a plurality of cement grooves are also arranged on the bottom surface of the inner side pad and the outer side pad.

[0016] Further, the cement grooves in the area surrounded by the long wing, the short wing and the column and outside the area are area-in cement grooves and area-out cement grooves respectively, and the depth of the area-in cement grooves is less than the depth of the area-out cement grooves.

[0017] Further, the depth of the area-in cement grooves is 2 / 3-3 / 4 of the depth of the area-out cement grooves.

[0018] Further, the inner pad and the outer pad are fixedly installed on the tibial osteotomy surface by a tibial support.

[0019] Further, the top end of the tibial support is provided with a support groove, the lower part of the inner pad and the outer pad is fixedly installed in the support groove; the lower end of the tibial support is fixedly connected with the tibial osteotomy surface; the groove wall surface of the support groove is provided with an inclined surface, and the lower part of the inner pad and the outer pad is provided with an inclined matching surface which can be matched with the inclined surface.

[0020] Further, the lower part of the inner pad and the outer pad is provided with an insertion part, the connection part between the insertion part and the upper part of the inner pad and the outer pad is provided with a stepped surface which is arranged around the root of the insertion part; the inclined matching surface is located on the end surface of the insertion part along the y-axis direction.

[0021] Further, the stepped surface is provided with an anti-disengagement hook, the groove wall of the support groove is provided with a first clamping groove which can clamp the anti-disengagement hook; the end part of the insertion part is laterally protruded and provided with a lateral clamping part, and the groove wall of the support groove is provided with a second clamping groove which can clamp the lateral clamping part; the first clamping groove and the second clamping groove are respectively located at the two ends of the groove wall of the support groove along the x-axis direction.

[0022] Further, the first bionic concave curved surface has a first arc-shaped a curved surface, a second arc-shaped a curved surface, a third arc-shaped a curved surface and a fourth arc-shaped a curved surface which are sequentially and continuously connected along the x-axis direction; the second bionic concave curved surface has a first arc-shaped b curved surface, a second arc-shaped b curved surface, a third arc-shaped b curved surface and a fourth arc-shaped b curved surface which are sequentially and continuously connected along the x-axis direction.

[0023] The radius of the first arc-shaped a curved surface, the second arc-shaped a curved surface, the third arc-shaped a curved surface and the fourth arc-shaped a curved surface is R a1 <R a2 <R a4 <R a3 ; the radius of the first arc-shaped b curved surface, the second arc-shaped b curved surface, the third arc-shaped b curved surface and the fourth arc-shaped b curved surface is R b4 <R b1 <R b3 <R b2 .

[0024] Compared with the prior art, the bionic unicompartmental prosthesis provided by the application can at least achieve one of the following beneficial effects:

[0025] 1. It is a fixed platform prosthesis, which can effectively prevent the spacer from dislocation; by more contact of the joint surface, it reduces the wear between the prostheses and improves the service life of the prostheses; the joint surface also has a certain limitation, which can adapt to different cross ligament conditions and provide more stability for the joint; at the same time, the joint surface adopts bionic anatomy, and the knee joint movement can be more natural.

[0026] 2. The single condyle spacer provided by the application has the advantages that the knee joint movement is more natural, and more clinical solutions are provided for the operator, so that the operator can select a single condyle spacer with a suitable size according to the joint gap formed by the cross ligament and the collateral ligament without increasing the amount of osteotomy, reduce the operation process and operation time, directly reduce the operation room operation cost, and at the same time, the patient obtains better prosthesis use effect, the flexion and extension movement trajectory is closer to the physiological state, the postoperative knee joint activity and stability are improved compared with the traditional prosthesis, the gait is more natural, the long-term medical expenditure of each patient can be saved by prolonging the revision cycle.

[0027] 3. The combination of the fixed platform structure and the bionic anatomical joint surface can solve the two technical pain points of the traditional single condyle replacement at the same time: it avoids the dislocation risk of the mobile platform spacer, and at the same time, the contact area is increased by about 30-50% through the optimization of the joint contact surface design, which significantly reduces the wear rate, and theoretically prolongs the service life of the prosthesis to more than 20 years. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present specification or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present specification, and other drawings can also be obtained by those skilled in the art based on these drawings.

[0029] Figure 1 A schematic view of a bionic unicompartmental prosthesis provided by the application is shown in the figure.

[0030] Figure 2 A schematic view of the bionic concave surface structure of the medial spacer of the bionic unicompartmental prosthesis provided by the application is shown in the figure.

[0031] Figure 3 A schematic view of the bionic concave surface structure of the lateral spacer of the bionic unicompartmental prosthesis provided by the application is shown in the figure.

[0032] Figure 4 A first angle structure schematic view of a single condyle spacer of a first structure type provided by the application is shown in the figure.

[0033] Figure 5 A second angle structure schematic view of a single condyle spacer of a first structure type provided by the application is shown in the figure.

[0034] Figure 6 The third angle structure diagram of the unicompartmental tibial spacer of the first structure type according to the present application;

[0035] Figure 7 The stress distribution diagram of the tibial resection surface for implanting the existing cement tibial spacer;

[0036] Figure 8 The stress distribution diagram of the tibial resection surface for implanting the unicompartmental tibial spacer of the first structure type according to the present application;

[0037] Figure 9 The structure diagram of the unicompartmental tibial spacer of the second structure type according to the present application installed on the tibial tray;

[0038] Figure 10 The structure diagram of the Figure 9 A-A sectional structure diagram;

[0039] Figure 11 The exploded structure diagram of the unicompartmental tibial spacer of the second structure type according to the present application and the tibial tray;

[0040] Figure 12 The sectional structure diagram of the unicompartmental tibial spacer of the second structure type according to the present application and the tibial tray after exploded;

[0041] Figure 13 The partial structure diagram of the tibial tray suitable for the unicompartmental tibial spacer of the second structure type according to the present application.

[0042] Reference signs:

[0043] 1, tibial spacer; 11, medial spacer; 111, first bionic concave surface; 1111, first arc-shaped a surface; 1112, second arc-shaped a surface; 1113, third arc-shaped a surface; 1114, fourth arc-shaped a surface; 12, lateral spacer; 121, second bionic concave surface; 1211, first arc-shaped b surface; 1212, second arc-shaped b surface; 1213, third arc-shaped b surface; 1214, fourth arc-shaped b surface;

[0044] 2, tibial resection surface; 21, insertion slot;

[0045] 3, insertion type locking structure; 31, long wing; 311, first lateral slot; 312, second lateral slot; 32, short wing; 321, third lateral slot; 33, column; 331, annular slot; 34, cement slot; 341, intra-regional cement slot; 342, extra-regional cement slot;

[0046] 4, tibial tray; 41, tray slot; 42, inclined surface; 43, first clamping slot; 44, second clamping slot;

[0047] 5. Insertion part; 51. Inclined mating surface; 52. Stepped surface; 53. Anti-disengagement hook; 54. Lateral locking part; 55. Lateral arc-shaped surface; 56. Front plane. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be noted that, unless otherwise specified, the implementation methods and features in the implementation methods in this disclosure can be combined, separated, interchanged, and / or rearranged. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] In the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0050] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0051] Example 1

[0052] In one specific embodiment of the present application, a bionic unicompartmental prosthesis is disclosed, which comprises a tibial pad 1, the tibial pad 1 comprising a unicompartmental pad piece divided into medial and lateral sides, that is, the tibial pad 1 has a medial pad 11 and a lateral pad 12: the medial pad 11 is configured as a medial tibial plateau prosthesis of a knee joint; the lateral pad 12 is configured as a lateral tibial plateau prosthesis of a knee joint; the medial pad 11 and the lateral pad 12 both have a unicompartmental anatomical shape determined according to the medial tibial plateau and the lateral tibial plateau of a human knee joint; the top of the medial pad 11 and the top of the lateral pad 12 have a first bionic concave surface 111 and a second bionic concave surface 121, respectively; the first bionic concave surface 111 and the second bionic concave surface 121 both have four arc surfaces, and the radii of the four arc surfaces are determined according to the top surface curve of the medial tibial plateau and the lateral tibial plateau of a human knee joint.

[0053] For ease of description, taking a standing human body as an example, referring to Figure 1 , the direction of the human body looking at the front is defined as the x-axis direction, and the y-axis direction refers to the direction viewed from the side of the standing human body, which is perpendicular to the x-axis direction.

[0054] In this embodiment, the medial pad 11 and the lateral pad 12 can both be referred to as “unicompartmental pad pieces”. The unicompartmental pad pieces can be made into products of multiple size parameters according to the body structure parameter characteristics of different populations, so as to facilitate doctors to select different types of products according to the patient's condition.

[0055] In this embodiment, the unicompartmental pad piece has an anatomical shape, and the shapes of the medial pad 11 and the lateral pad 12 are not symmetrical but anatomical shapes, which can better increase the bone surface coverage, reduce the platform contact stress, and improve the long-term stability of the joint prosthesis.

[0056] In one optional embodiment, as shown in Figures 2-3 , the first bionic concave surface 111 has a first arc a surface 1111, a second arc a surface 1112, a third arc a surface 1113, and a fourth arc a surface 1114 connected in sequence along the x-axis direction; the second bionic concave surface 121 has a first arc b surface 1211, a second arc b surface 1212, a third arc b surface 1213, and a fourth arc b surface 1214 connected in sequence along the x-axis direction; wherein the radii of the first arc a surface 1111, the second arc a surface 1112, the third arc a surface 1113, and the fourth arc a surface 1114 are R a1 <R a2 <R a4 <R a3; the radii of the first arc-shaped b curved surface 1211, the second arc-shaped b curved surface 1212, the third arc-shaped b curved surface 1213 and the fourth arc-shaped b curved surface 1214 are R b4 <R b1 <R b3 <R b2 .

[0057] Optionally, R a1 = 6-12 mm, R a2 = 10-15 mm, R a3 = 28-40 mm, R a4 = 13-25 mm;

[0058] R b1 = 18-25 mm, R b2 = 40-60 mm, R b3 = 25-40 mm, R b4 = 15-22 mm.

[0059] Exemplarily, R a1 = 9 mm, R a2 = 13 mm, R a3 = 33 mm, R a4 = 17 mm;

[0060] R b1 = 22 mm, R b2 = 53 mm, R b3 = 33 mm, R b4 = 20 mm.

[0061] It should be noted that the arc lengths of the different arc-shaped surfaces on the bionic concave surfaces of the inner side pad 11 and the outer side pad 12 in the embodiment are obtained by G2 curves through natural transition according to the anteroposterior diameter and the anteroposterior height of the anatomical shape.

[0062] The first bionic concave surface 111 and the second bionic concave surface 121 of the embodiment are designed by using the above parameters, which can effectively reduce the wear and prolong the service life.

[0063] In the embodiment, the unicompartmental pad is divided into two structural types according to different fixed mounting modes of the unicompartmental pad and the tibial bone resection surface 2.

[0064] Figures 4-6The first structure type of single knee spacer is shown, which is a cement type tibial spacer, namely the medial spacer 11 and the lateral spacer 12 are fixedly installed on the tibial bone cut surface 2 by using bone cement. Specifically, the bottom surface of the medial spacer 11 and the lateral spacer 12 is provided with an insertion type locking structure 3, which can be inserted into the insertion slot 21 on the tibial bone cut surface 2. When the insertion type locking structure 3 is inserted into the insertion slot 21 on the tibial bone cut surface 2, the bottom surface of the medial spacer 11 and the lateral spacer 12 can be in contact with the tibial bone cut surface 2, and the bone cement is applied between the bottom surface of the medial spacer 11 and the lateral spacer 12 and the tibial bone cut surface 2 to fix the medial spacer 11 and the lateral spacer 12 with the tibial bone cut surface 2.

[0065] In a preferred embodiment, the insertion type locking structure 3 has a long wing 31, a short wing 32 and a column 33, the tibial bone cut surface 2 is provided with three insertion slots 21, and the sizes and shapes of the three insertion slots 21 match the long wing 31, the short wing 32 and the column 33; the length of the long wing 31 is greater than the length of the short wing 32, the long wing 31 is arranged perpendicular to the short wing 32, and the column 33 is arranged in the area surrounded by the long wing 31 and the short wing 32; wherein the length direction of the long wing 31 is arranged along the x-axis direction, and the length direction of the short wing 32 is arranged along the y-axis direction. Optionally, the column 33 is a cylinder, and the column 33 has a symmetry plane with the short wing 32, and the symmetry plane is parallel to the long wing 31. That is, the symmetry plane of the column 33 and the short wing 32 is parallel to the x-axis direction. Further, the height of the long wing 31, the short wing 32 and the column 33 is the same, the length of the short wing 32 is 1 / 4-1 / 3 of the length of the long wing 31, and the vertical distance between the axis of the column 33 and the long wing 31 is 7-10 mm.

[0066] In an optional embodiment, the side wall surface of the long wing 31 is provided with a first lateral groove 311 and a second lateral groove 312 arranged in parallel from top to bottom, the short wing 32 is provided with a third lateral groove 321, and the side surface of the column 33 is provided with an annular groove 331; wherein the distances from the first lateral groove 311, the second lateral groove 312, the third lateral groove 321 and the annular groove 331 to the bottom surface of the medial spacer 11 and the lateral spacer 12 are 6-8 mm, 2-4 mm, 3-4 mm and 3-4 mm respectively.

[0067] In this embodiment, the bottom surface of the medial spacer 11 and the lateral spacer 12 is also dispersedly provided with a plurality of cement grooves 34; by providing the cement grooves 34, the connection strength of the bone cement is increased.

[0068] In one of the alternative embodiments, the long wing 31, the short wing 32 and the column 33 form the inner and outer cement grooves 34, respectively, the inner cement groove 341 and the outer cement groove 342, the depth of the inner cement groove 341 is less than that of the outer cement groove 342; the depth of the inner cement groove 341 is 2 / 3-3 / 4 of that of the outer cement groove 342. The different depths of the cement grooves at different positions are designed to improve the connection strength of the bone cement and increase the mechanical strength of the main load position.

[0069] Compared with the existing gasket fixed by a single slot, the stress is mainly concentrated on the protruding structure, see Figure 7 , which is prone to loosening of the protruding structure, unstable fixation, increased wear and reduced service life of the gasket. The cement tibial gasket with the above structural parameters is implanted into the tibia, and the stress distribution on the tibial implant surface obtained by finite element analysis is Figure 8 It can be seen that the stress is mainly concentrated on the tibial osteotomy surface 2, the stress is shared, and the long-term stability of the prosthesis is better.

[0070] Figures 9-13 A second structure type of unicompartmental gasket is shown: the medial gasket 11 and the lateral gasket 12 are fixedly installed on the tibial osteotomy surface 2 by the tibial support 4. Specifically, the top end of the tibial support 4 is provided with a bracket groove 41, and the lower part of the medial gasket 11 and the lateral gasket 12 is fixedly installed in the bracket groove 41; the lower end of the tibial support 4 is fixedly connected with the tibial osteotomy surface 2; the slot wall surface of the bracket groove 41 has an inclined surface 42, and the lower part of the medial gasket 11 and the lateral gasket 12 is provided with an inclined matching surface 51 which can be matched with the inclined surface 42. When the medial gasket 11 and the lateral gasket 12 are installed in the bracket groove 41, the inclined surface 42 of the bracket groove 41 can be interference-fitted with the inclined matching surface 51 of the side surface of the medial gasket 11 and the lateral gasket 12, and the two inclined surfaces can prevent the side gasket from falling out.

[0071] In one of the alternative embodiments, the lower part of the medial gasket 11 and the lateral gasket 12 is provided with an insertion part 5, the insertion part 5 has a stepped surface 52 arranged around the root of the insertion part 5 at the connection between the upper part of the medial gasket 11 and the lateral gasket 12 and the insertion part 5; the inclined matching surface 51 is located on the insertion part 5 and is an end side wall surface of the insertion part 5 along the y-axis direction. The inclined matching surface 51 is approximately an inclined plane, and the other end side wall surface of the insertion part 5 along the y-axis direction is an arc-shaped side end surface, and the curvature of the arc-shaped side end surface is designed according to the single-condyle anatomical shape.

[0072] In one of the optional embodiments, the stepped surface 52 is provided with an anti-unhooking hook 53, and the groove wall of the bracket 41 is provided with a first clamping groove 43 capable of clamping the anti-unhooking hook 53; the end of the insertion part 5 is laterally protruding and provided with a lateral clamping part 54, and the groove wall of the bracket 41 is provided with a second clamping groove 44 capable of clamping the lateral clamping part 54; the anti-unhooking hook 53 is located at one end of the stepped surface 52 along the x-axis direction, and the lateral clamping part 54 is located at the other end of the insertion part 5 away from the anti-unhooking hook 53; the first clamping groove 43 and the second clamping groove 44 are respectively located at both ends of the groove wall of the bracket 41 along the x-axis direction.

[0073] In one of the optional embodiments, the insertion part 5 further has a lateral arc surface 55 and a front flat surface 56, the lateral arc surface 55 is arranged opposite to the inclined matching surface 51, and the front flat surface 56 is located at the other end of the insertion part 5 opposite to the lateral clamping part 54, that is, the lateral clamping part 54 and the front flat surface 56 are located at both ends of the side end surface of the insertion part 5. Optionally, the front flat surface 56 can be located on one side or both sides of the anti-unhooking hook 53. Among them, the lateral arc surface 55 and the front flat surface 56 are both vertical surfaces, and correspondingly, the groove wall surface of the bracket 41 has vertical surfaces corresponding to the lateral arc surface 55 and the front flat surface 56, and when the insertion part 5 is installed in the bracket 41, the insertion part is in interference fit with the groove wall surface of the bracket 41 at the positions of the lateral arc surface 55 and the front flat surface 56.

[0074] When the second structure type of unicompartmental spacer is used, the bracket 41 of the tibial tray 4 faces upward, the medial spacer 11 / lateral spacer 12 is first installed in the bracket 41 on the side of the lateral clamping part 54, and the lateral clamping part 54 is inserted into the second clamping groove 44, the position of the medial spacer 11 / lateral spacer 12 in the bracket 41 is adjusted so that the inclined matching surface 51 on the insertion part 5 slides below the inclined surface 42 of the groove wall surface of the bracket 41; the medial spacer 11 / lateral spacer 12 is pressed downward on the side of the anti-unhooking hook 53 until the anti-unhooking hook 53 is clamped into the first clamping groove 43 on the groove wall of the bracket 41, and the installation of the unicompartmental spacer and the tibial tray 4 is completed. After assembly, the inclined matching surface 51 of the insertion part 5 and the inclined surface 42 of the bracket 41 form a first limiting position, the anti-unhooking hook 53 and the first clamping groove 43 form a second limiting position, and the positions of the lateral arc surface 55 and the front flat surface 56 and the interference fit positions of the groove wall surface of the bracket 41 form a third limiting position, and the three limiting positions jointly improve the installation stability of the spacer and the tibial tray and effectively prevent unhooking.

[0075] Compared with the prior art, the bionic unicompartmental prosthesis provided by the embodiment can achieve the following beneficial effects:

[0076] 1. It is a fixed platform prosthesis, which can effectively prevent the spacer from dislodging; it reduces wear between prostheses and improves prosthesis life by increasing the contact between articular surfaces; the articular surfaces also have a certain degree of restriction, which can adapt to different cruciate ligament conditions and provide more stability to the joint; at the same time, the articular surfaces adopt a biomimetic anatomical shape, so that the knee joint movement can be more natural.

[0077] 2. This invention provides a unicompartmental implant that allows for more natural knee joint movement and offers surgeons more clinical solutions. It allows surgeons to select the appropriate size unicompartmental implant based on the joint space formed by the cruciate ligaments and collateral ligaments without increasing the amount of osteotomy, reducing surgical procedures, shortening operation time, and directly lowering operating room operating costs. Simultaneously, patients achieve better prosthesis performance, with flexion and extension trajectories closer to physiological states. Postoperative knee joint range of motion and stability are improved compared to traditional prostheses, resulting in a more natural gait. By extending the revision period, it can save long-term medical expenses for each patient.

[0078] 3. By combining a fixed platform structure with a biomimetic anatomical joint surface, this invention can simultaneously solve two major technical problems of traditional unicompartmental arthroplasty: it avoids the risk of dislocation of the movable platform pad and increases the contact area by about 30-50% through optimized joint contact surface design, significantly reducing the wear rate and theoretically extending the service life of the prosthesis to more than 20 years.

[0079] 4. By collecting, organizing, and analyzing tibial model data, and combining it with the concept of unicompartmental implants, a biomimetic prosthesis structure was designed to replace the tibial plateau meniscus, enabling targeted treatment of unilateral compartment arthritis. This structure can replace both the meniscus and the tibial plateau. Furthermore, due to the biomimetic design, it increases contact with the femoral side, improving femoral restraint without restricting movement, thereby enhancing stability, reducing wear, and achieving a more natural gait.

[0080] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above description is only a specific embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A biomimetic unicompartmental prosthesis comprising a tibial pad, characterized in that, The tibial pad has: A medial pad configured as a medial tibial plateau prosthesis of a knee joint; A lateral pad configured as a lateral tibial plateau prosthesis of a knee joint; wherein the medial pad and the lateral pad each have a single condyle anatomical shape determined according to the medial tibial plateau and the lateral tibial plateau of a human knee joint; the top part of the medial pad and the lateral pad has a first bionic concave surface and a second bionic concave surface respectively; the first bionic concave surface and the second bionic concave surface each have four arc surfaces.

2. The biomimetic unicompartmental prosthesis according to claim 1, characterized in that The medial pad and the lateral pad are fixedly installed on a tibial bone resection surface by using bone cement.

3. The bionic unicompartmental prosthesis according to claim 2, characterized in that, The bottom surface of the medial pad and the lateral pad is convexly provided with an insertion type locking structure which can be inserted into a slot on the tibial bone resection surface.

4. The bionic unicompartmental prosthesis according to claim 3, characterized in that, The insertion type locking structure has a long wing, a short wing and a column, the length of the long wing is greater than the length of the short wing, the long wing is arranged vertically to the short wing, and the column is arranged in the area surrounded by the long wing and the short wing. Wherein, the length direction of the long wing is arranged along the x-axis direction, and the length direction of the short wing is arranged along the y-axis direction; the x-axis direction refers to the direction of the front of the human body, and the y-axis direction refers to the direction from the side of the human body, which is perpendicular to the x-axis direction.

5. The biomimetic unicompartmental prosthesis of claim 1, wherein, The bottom surface of the medial pad and the lateral pad is also dispersedly provided with a plurality of cement grooves.

6. The biomimetic unicompartmental prosthesis of claim 1, wherein, The medial pad and the lateral pad are fixedly installed on a tibial bone resection surface by using a tibial bone support.

7. The bionic unicompartmental prosthesis according to claim 6, characterized in that The top end of the tibial bone support is provided with a support slot, and the lower part of the medial pad and the lateral pad is fixedly installed in the support slot; the lower end of the tibial bone support is fixedly connected with the tibial bone resection surface. The slot wall surface of the support slot has an inclined surface, and the lower part side wall surface of the medial pad and the lateral pad is provided with an inclined matching surface which can be matched with the inclined surface.

8. The biomimetic unicompartmental prosthesis according to claim 7, characterized in that The lower part of the medial pad and the lateral pad is provided with an insertion part, and the connection between the insertion part and the upper part of the medial pad and the lateral pad has a stepped surface arranged around the root of the insertion part. The inclined matching surface is located on the insertion part, which is an end side wall surface of the insertion part along the y-axis direction.

9. The biomimetic unicompartmental prosthesis according to claim 8, characterized in that The stepped surface is provided with an anti-disengagement hook, and the slot wall of the support slot is provided with a first clamping groove which can clamp the anti-disengagement hook. The end part of the insertion part is laterally convexly provided with a lateral clamping part, and the slot wall of the support slot is provided with a second clamping groove which can clamp the lateral clamping part. The first clamping groove and the second clamping groove are respectively located at both ends of the slot wall of the support slot along the x-axis direction.

10. The unicompartmental prosthesis of claim 1, wherein, The first bionic concave surface has a first arc a surface, a second arc a surface, a third arc a surface and a fourth arc a surface which are sequentially connected in sequence along the x-axis direction; The second bionic concave surface has a first arc b surface, a second arc b surface, a third arc b surface and a fourth arc b surface which are sequentially connected in sequence along the x-axis direction; Wherein, the radius of the first arc-shaped a curved surface, the second arc-shaped a curved surface, the third arc-shaped a curved surface and the fourth arc-shaped a curved surface are R a1 <R a2 <R a4 <R a3 ; Radii of the first arc-shaped b curved surface, the second arc-shaped b curved surface, the third arc-shaped b curved surface and the fourth arc-shaped b curved surface are R b4 <R b1 <R b3 <R b2 .

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