Artificial knee joint

Abstract

The application discloses an artificial knee joint, which comprises a femoral condyle prosthesis and a tibial plateau prosthesis, the tibial plateau prosthesis comprises a medial tibial plateau prosthesis and a lateral tibial plateau prosthesis arranged on both sides of an intercondylar ridge of the tibial plateau respectively, and the artificial knee joint further comprises a positioning pin for fixing the tibial plateau prosthesis; a prosthesis slot is formed in the bottom surface of the tibial plateau prosthesis, a tibial slot is formed in the tibia below the tibial plateau prosthesis, the prosthesis slot corresponds to the tibial slot, and together they form a limiting hole for accommodating the positioning pin; the cooperation between the positioning pin and the limiting hole can ensure that the relative position between the medial tibial plateau prosthesis and the lateral tibial plateau prosthesis is stable and balanced; the tibial plateau prosthesis comprises an upper gasket and a lower gasket, and an elastic member is arranged on the lower gasket, which can not only reduce vibration but also play a limiting and fixing role.

Description

TECHNICAL FIELD

[0001] The present application relates to a medical artificial joint prosthesis, in particular to an artificial knee joint. BACKGROUND

[0002] At present, knee replacement surgery is the most fundamental treatment for knee joint diseases and injuries in the world. In the replacement surgery, the joint prosthesis, also known as artificial knee joint, is implanted into the human body to replace the natural knee joint of the human body. With the gradual progress of science and technology, the further requirements for artificial knee joint and replacement surgery are becoming higher and higher. People not only hope to reduce pain, but also hope to improve the service life, and even hope to achieve the level of normal healthy people after recovery. For this reason, various artificial knee joints have gradually appeared, and various ideas have been put forward. However, the current mainstream surgical method and artificial knee joint still cannot meet the above requirements.

[0003] The two main leg bones of the human body are the femur and the tibia. The femur is on the top, and the tibia is on the bottom. The position where the femur and the tibia intersect and interact is the knee joint. The part of the femur in the knee joint is called the lower end of the femur, and the part of the tibia in the knee joint is called the upper end of the tibia. The lower end of the femur and the upper end of the tibia are enlarged to provide a support basis for the stability of the knee joint.

[0004] The lower end of the femur forms two separate condyles, the lower surface of which is smooth and rounded and covered with articular cartilage. The two separate condyles are not symmetrical, with the medial condyle being larger and the lateral condyle being smaller to adapt to the different stress conditions on the medial and lateral sides. The upper end of the tibia includes shallow, concave, articular cartilage-covered lateral and medial platforms. The medial platform is larger than the lateral platform, and the entire tibial platform is separated by a ridge or tubercle between the lateral and medial platforms.

[0005] The patella (kneecap) is embedded in the quadriceps tendon, which connects the quadriceps muscle tissue on the front of the upper leg to the patella. The patellar ligament connects the patella to the tibia just below the knee joint. The combination of the quadriceps tendon, the patella, and the patellar ligament acts like a pulley, transmitting the force generated by the quadriceps muscle tissue to the tibia through the flexed knee joint, thereby straightening the leg or slowing down the flexion speed. Obviously, the patella also has other functions to protect the knee joint from impact damage.

[0006] The function of the cruciate ligament is to position the condyles approximately on the tibia during flexion and extension. During flexion of the knee joint, the tension applied by the anterior cruciate ligament limits posterior displacement of the condyles, and during extension of the knee joint, the posterior cruciate ligament limits anterior displacement of the condyles.

[0007] The knee joint meniscus plays a vital role in the knee joint to function normally, in addition to increasing the symmetry of the joint, the meniscus is buffered and differentiated when force passes through the knee joint, reducing friction and impact between the femur and tibia;

[0008] However, in the current popular knee replacement surgery, the natural tibial platform is often directly resected, replaced with an artificial tibial platform, and a similar femoral condyle prosthesis is installed on the surface of the femur, so that the new femoral condyle prosthesis interacts with the artificial tibial platform, which results in the absence of cruciate ligaments and meniscus in the postoperative knee joint, and even the absence of patella, so the current surgical method and the characteristics of the artificial knee itself lead to the fact that the desired recovery effect is impossible after the surgery, and such surgery destroys the original physiological structure and characteristics of the knee joint, causing permanent and irreversible damage to the knee joint, and urgent adjustment is needed, and a new artificial knee joint that can retain the cruciate ligament, patella, and has the function of meniscal cushioning is needed.

[0009] In addition, through years of clinical research, it is known that in knee joint diseases, the damage degree of the medial condyle and the lateral condyle, the medial platform and the lateral platform is not the same, and is often affected by human behavior habits, work habits, etc., the condyle or platform located on the medial side is damaged first, and then the condyle or platform on the other side is accelerated to damage, and the patient suffers great pain during this process, if surgery is performed during this process, the undamaged side will also be resected because the tibial platform and the new femoral condyle are integral; and most knee joint diseases are caused by degeneration and wear of the meniscus, femoral condyle or tibial platform, and the cruciate ligament and patella are rarely damaged;

[0010] Therefore, someone proposes to replace the existing integral knee joint with a half-condyle knee joint, although this idea is worth promoting, but in the actual implementation process, great difficulties are encountered, and finally it cannot be realized, or its real effect is still lower than the original integral knee joint; the main problem is that when the half-condyle knee joint is replaced, the replaced part and the intact part do not match in function and height, and cannot effectively delay the damage speed of the intact part, when the other part of the knee joint that is originally intact is also damaged, the artificial knee joint still needs to be replaced, at this time, if the half-condyle knee joint is also used, the two half-condyle knee joints are difficult to coordinate in height, size, elasticity, etc., and the use effect is poor, if the integral knee joint is replaced, the originally replaced half-condyle knee joint is meaningless, and it also involves the secondary damage and installation of the tibia and femur.

[0011] Due to the above problems, the inventor of the present application has made in-depth research on the existing artificial knee joint and designed a new artificial knee joint that can solve the above problems. SUMMARY

[0012] In order to overcome the above problems, the present inventors have made intensive studies and designed an artificial knee joint, which comprises a femoral condyle prosthesis and a tibial plateau prosthesis, the tibial plateau prosthesis comprising a tibial plateau medial prosthesis and a tibial plateau lateral prosthesis arranged on both sides of an intercondylar ridge of the tibial plateau respectively, and further comprising a positioning pin for fixing the tibial plateau prosthesis; a prosthesis slot is formed on the bottom surface of the tibial plateau prosthesis, and a tibial slot is formed on the top of the tibia below the tibial plateau prosthesis, the prosthesis slot and the tibial slot correspond to each other and together form a limiting hole for accommodating the positioning pin, the limiting hole penetrates the intercondylar ridge of the tibial plateau and communicates the tibial plateau medial prosthesis and the tibial plateau lateral prosthesis, and the artificial knee joint further comprises a positioning pin which can be embedded into the limiting hole, and the cooperation of the positioning pin and the limiting hole can ensure the relative position between the tibial plateau medial prosthesis and the tibial plateau lateral prosthesis to be stable and balanced, thereby achieving the present application.

[0013] Specifically, the present application aims to provide an artificial knee joint, which comprises a femoral condyle prosthesis 1 and a tibial plateau prosthesis 2,

[0014] The tibial plateau prosthesis 2 comprises a tibial plateau medial prosthesis 201 and a tibial plateau lateral prosthesis 202 which are independent of each other,

[0015] The tibial plateau medial prosthesis 201 and the tibial plateau lateral prosthesis 202 are arranged on both sides of the intercondylar ridge 31 of the tibial plateau and below the femoral condyle prosthesis 1.

[0016] Among them, the tibial plateau prosthesis 2 is placed below the posterior side of the patella.

[0017] Among them, the tibial plateau prosthesis 2 is placed below the posterior side of the patella.

[0018] Among them, the tibial plateau prosthesis 2 is placed below the posterior side of the patella.

[0019] Among them, the tibial plateau prosthesis 2 is placed below the posterior side of the patella.

[0020] Among them, the tibial plateau prosthesis 2 is placed below the posterior side of the patella.

[0021] The prosthesis slot 23 and the tibial slot 32 together form a limiting hole 4 for installing the positioning pin 5, and the limiting hole penetrates the intercondylar ridge 31 of the tibial plateau.

[0022] The medial hemicondylar prosthesis 201 and the lateral tibial plateau prosthesis 202 each include an upper spacer 21 and a lower spacer 22.

[0023] Among them, an elastic member 6 is provided on the lower pad 22 to buffer the impact force transmitted from the femoral condyle prosthesis 1 to the upper pad of the tibial plateau prosthesis 2, so that the upper pad 21 has a meniscus-like function.

[0024] The elastic member 6 passes through the lower pad 22 and is fixedly installed on the lower pad 22, with its upper end extending above the lower pad 22 and resting on the lower surface of the upper pad.

[0025] The elastic member 6 includes a sleeve 61 and a spring 62. The lower end of the spring 62 is embedded in the sleeve 61, and the upper end of the spring rests on the lower surface of the upper washer.

[0026] The sleeve 61 passes through the lower gasket 22, and the bottom end of the sleeve is installed in the cavity 7 on the tibia.

[0027] The sleeve 61 is provided with a bolt 63 at the bottom to adjust the tension of the spring 62.

[0028] The present invention also provides a method for using the artificial knee joint as described above, the method comprising the following steps:

[0029] Step 1: Install the femoral condyle prosthesis 1 onto the femoral condyle;

[0030] Step 2: Create a space on the tibial plateau to install the tibial plateau prosthesis 2.

[0031] Step 3: Carve out a tibial notch 32 on the tibia and extend the tibial notch 32 to the intercondylar ridge 31 of the tibial plateau, forming an intercondylar ridge foramen 33 on the intercondylar ridge 31 of the tibial plateau;

[0032] Step 4: Create a cavity 7 in the tibia;

[0033] Step 5: Insert the sleeve on the tibial plateau prosthesis 2 into the cavity 7, and at the same time adjust the relative positions of the prosthesis notch 21, the tibial notch 32 and the intercondylar ridge foramen 33 so that the prosthesis notch 21 together with the tibial notch 32 and the intercondylar ridge foramen 33 forms the limiting hole 4.

[0034] Step 6: Install the positioning pin 5 into the limiting hole 4. After the positioning pin 5 is fixed, fix the tibial plateau prosthesis 2 with bone cement.

[0035] Preferably, before performing step 5, the tension of spring 62 is adjusted by rotating bolt 63.

[0036] The beneficial effects of this invention include:

[0037] (1) The artificial knee joint provided by the application has two separate tibial plateau medial prostheses and tibial plateau lateral prostheses, which can be placed on both sides of the intercondylar ridge of the tibial plateau respectively, so that the intercondylar ridge of the tibial plateau does not need to be cut off or damaged, and the crossing ligament on the intercondylar ridge of the tibial plateau can be kept intact, thereby greatly enhancing the use effect and patient experience;

[0038] (2) The artificial knee joint provided by the application has two separate tibial plateau medial prostheses and tibial plateau lateral prostheses, which can be implanted in stages according to the condition, and the actual application is more flexible and convenient;

[0039] (3) The tibial plateau prosthesis of the artificial knee joint provided by the application is provided with an elastic member, which can simulate the function of the meniscus, provide a buffering and damping effect, and make the artificial knee joint more substantially similar to the natural knee joint;

[0040] (4) The spring elasticity / elasticity of the elastic member of the tibial plateau prosthesis of the artificial knee joint provided by the application is adjustable, which can be adjusted according to different ages and physical conditions, and can ensure that the spring elasticity / elasticity is in the best state;

[0041] (5) The elastic member of the tibial plateau prosthesis of the artificial knee joint provided by the application is arranged in a downwardly protruding cylindrical structure, which is embedded in the hole cavity on the tibia, thereby also playing a limiting and fixing role on the tibial plateau prosthesis;

[0042] (6) The tibial plateau prosthesis of the artificial knee joint provided by the application is provided with a prosthesis slot and a positioning pin which communicates the tibial plateau medial prosthesis and the tibial plateau lateral prosthesis and passes through the intercondylar ridge of the tibial plateau, thereby limiting and fixing the relative position between the two tibial plateau prostheses in all directions, making the artificial knee joint balanced in stress, stable as a whole, long in service life, and good in patient experience;

[0043] (7) The artificial knee joint provided by the application only replaces a small part of the femur and tibia, does not damage and destroy other physiological components near the femur and tibia, and does not affect the normal physiological function, so that the relevant physiological structures in the knee joint such as the patella and the cruciate ligament can be reserved after the operation, thereby having good postoperative recovery effect. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 An assembly explosion view of the artificial knee joint according to a preferred embodiment of the application is shown;

[0045] Figure 2 A schematic view of a commonly used integral femoral prosthesis structure in the prior art artificial knee joint is shown;

[0046] Figure 3 Fig. 1 shows a schematic view of a femoral condyle prosthesis according to a preferred embodiment of the present application;

[0047] Figure 4 Fig. 2 shows a schematic view of a femoral condyle prosthesis according to a preferred embodiment of the present application;

[0048] Figure 5 Fig. 3 shows a schematic view of a femoral condyle prosthesis according to a preferred embodiment of the present application;

[0049] Figure 6 Fig. 4 shows a schematic view of a femoral condyle prosthesis according to a preferred embodiment of the present application;

[0050] Figure 7 Fig. 5 shows a schematic view of a tibial platform medial prosthesis according to a preferred embodiment of the present application;

[0051] Figure 8 Fig. 6 shows a schematic view of a tibial platform prosthesis upper elastic member cross section according to a preferred embodiment of the present application;

[0052] Figure 9 Fig. 7 shows a schematic view of a tibia structure to house a tibial platform prosthesis according to a preferred embodiment of the present application;

[0053] Figure 10 Fig. 8 shows a schematic view of a tibia structure to house a tibial platform medial prosthesis or a tibial platform lateral prosthesis according to a preferred embodiment of the present application;

[0054] Figure 11 Fig. 9 shows a schematic view of a femoral condyle prosthesis assembly with femur according to a preferred embodiment of the present application;

[0055] Figure 12 Fig. 10 shows a schematic view of a femoral condyle prosthesis assembly with femur after assembly according to a preferred embodiment of the present application.

[0056] BRIEF DESCRIPTION OF THE DRAWINGS

[0057] 1 - femoral condyle prosthesis

[0058] 101 - femoral medial condyle prosthesis

[0059] 102 - femoral lateral condyle prosthesis

[0060] 11 - front cover

[0061] 12 - fixation spike

[0062] 13-Rear Cover

[0063] 14-Fixing Pin

[0064] 2-Tibial plateau prosthesis

[0065] 201-Medial tibial plateau prosthesis

[0066] 202-Lateral tibial plateau prosthesis

[0067] 21-Upper gasket

[0068] 22-Lower gasket

[0069] 23-Prosthesis notch

[0070] 3-Tibia

[0071] 31-Tibial plateau intercondylar ridge

[0072] 32-Tibial notch

[0073] 33-Intercondylar ridge opening

[0074] 4-Limiting Hole

[0075] 5-Positioning Pin

[0076] 6-Elastic Components

[0077] 61-Sleeve

[0078] 62-Spring

[0079] 63- Bolt

[0080] 7-hole cavity

[0081] 8-Femur Detailed Implementation

[0082] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Through these descriptions, the features and advantages of the present invention will become clearer and more apparent.

[0083] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments. Although various aspects of embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless specifically indicated otherwise.

[0084] The artificial knee joint provided by the present invention, such as Figure 1As shown in the figure, the artificial knee joint comprises a femoral condyle prosthesis 1 and a tibial plateau prosthesis 2, wherein the femoral condyle prosthesis 1 is arranged at the lower end of the femur 8 and replaces part of the bone structure at the lower end of the femur, and the tibial plateau prosthesis 2 is arranged at the upper end of the tibia 3 and replaces part of the bone structure on the tibial plateau at the upper end of the tibia; the tibial plateau in the present application refers to the surface of the tibia that contacts the lower end of the femur, and the central part of the tibial plateau is provided with a tibial intercondylar ridge 31, also known as a protuberance or a tubercle, on which the cruciate ligament is attached; the tibial plateau is mainly composed of a medial plateau and a lateral plateau on both sides of the tibial intercondylar ridge.

[0085] The tibial plateau prosthesis 2 comprises a tibial plateau medial prosthesis 201 and a tibial plateau lateral prosthesis 202, which are independent of each other and are used to replace the medial plateau and the lateral plateau, respectively. After the tibial plateau prosthesis replaces the medial plateau and / or the lateral plateau, the height of the un-replaced part of the tibial plateau (including the tibial intercondylar ridge) is consistent with the height of the tibial plateau prosthesis, that is, after a part of the tibial structure is replaced by the tibial plateau prosthesis, the height and the shape of the tibia do not change.

[0086] The femoral condyle prosthesis can be two separate unicompartmental femoral condyle prostheses or one integrated bicompartmental femoral condyle prosthesis. Figure 2 As shown in the figure, the integrated bicompartmental femoral condyle prosthesis has a large volume and weight, and the prosthesis will block the femoral trochlea and rub against the patella due to the change of the trochlear track, so an artificial patella replacement is often required to ensure normal operation.

[0087] Preferably, the femoral condyle prosthesis comprises two separate unicompartmental femoral condyle prostheses, namely a femoral medial unicompartmental femoral condyle prosthesis 101 and a femoral lateral unicompartmental femoral condyle prosthesis 102, which are independent of each other; the femoral medial unicompartmental femoral condyle prosthesis 101 is arranged on the medial unicompartmental femur and abuts against the top surface of the tibial plateau medial prosthesis 201, and the femoral lateral unicompartmental femoral condyle prosthesis 102 is arranged on the lateral unicompartmental femur and abuts against the top surface of the tibial plateau lateral prosthesis 202.

[0088] The femoral medial unicompartmental femoral condyle prosthesis 101 and the femoral lateral unicompartmental femoral condyle prosthesis 102 are basically similar in overall shape and composition, and are approximately mirror-symmetric. However, due to the slight differences in size and shape between the medial unicompartmental femur and the lateral unicompartmental femur, the femoral medial unicompartmental femoral condyle prosthesis 101 and the femoral lateral unicompartmental femoral condyle prosthesis 102 are not completely symmetric. Since the components of the femoral medial unicompartmental femoral condyle prosthesis 101 and the femoral lateral unicompartmental femoral condyle prosthesis 102 are basically consistent, the femoral medial unicompartmental femoral condyle prosthesis 101 will be described as an example, which comprises a front cover 11, a fixation spike 12, a rear cover 13 and a fixation pin 14, as shown in Figure 1 and Figure 3

[0089] Specifically, as shown in Figure 11 and​Figure 12 As shown in the figure, the femoral intracodyl prosthesis 101 is in the shape of the part of the femur it replaces, and its outer surface is arc-shaped. The front cover 11 and the back cover 13 are respectively arranged at the two ends of the femoral intracodyl prosthesis 101, so as to fix the femoral intracodyl prosthesis 101 on the femur. The top end of the back cover 13 is inclined towards the front cover.

[0090] When the femoral intracodyl prosthesis is installed, a concave prosthesis fixing area is first excavated on the femur. After the femoral intracodyl prosthesis is installed in the area, the area is just filled, so that the femur returns to the state before the prosthesis fixing area is excavated. That is, the femoral intracodyl prosthesis 101 is fixed on the femur by embedding into the prosthesis fixing area.

[0091] The fixing spike 12 and the fixing pin 14 are respectively arranged on the inner sides of the femoral intracodyl prosthesis 101 and the femoral extracodyl prosthesis 102. When the prosthesis fixing area is processed on the femur, a blind hole is also excavated in the spongiosa at the corresponding position. When the femoral intracodyl prosthesis 101 or the femoral extracodyl prosthesis 102 is buckled in the prosthesis fixing area, the fixing pin 14 is embedded into the blind hole.

[0092] Meanwhile, a tapered groove / tapered hole is arranged on the spongiosa near the front cortical bone, wherein the front cortical bone refers to the cortical bone in contact with the front cover 11. The specific shape and number of the tapered groove / tapered hole correspond to the shape and number of the fixing spike 12. When the femoral intracodyl prosthesis 101 or the femoral extracodyl prosthesis 102 is buckled in the prosthesis fixing area, the sharp end of the fixing spike 12 is inserted into the tapered groove / tapered hole.

[0093] Preferably, the diameter of the blind hole is slightly smaller than the outer diameter of the fixing pin 14. During the embedding of the fixing pin 14 into the blind hole, the diameter of the blind hole is inevitably expanded, which compresses the spongiosa area, thereby forming a tight fixation.

[0094] Preferably, the fixing spike 12 and the fixing pin 14 can be one or more. In this application, preferably, there are two fixing spikes and one fixing pin. Correspondingly, the number of the blind hole and the tapered groove / tapered hole matches the number of the fixing pin 14 and the fixing spike 12.

[0095] The area of the femur which is in contact with the front cover 11 and the rear cover 13 is the cortical bone area, which has high strength and toughness; preferably, the front cover 11 is adjacent to the fixing spike 12, the front cover 11 is buckled outside the cortical bone, the fixing spike 12 is inserted into the cancellous bone, and the fixing spike 12 is abutted on the cortical bone from the inside, so as to tighten the cortical bone, and the rear cover 13 forms a nest groove together, and is buckled and fixed on the femur; meanwhile, the front cover 11 and the fixing spike 12 together form a groove structure with a V-shaped cross section, and the cortical bone of the femur which is ground is abutted on the bottom of the groove structure; the fixing spike 12 and the groove structure with a V-shaped cross section together assist the front cover 11 to fix the cortical bone, so that the front cover 11 and the rear cover 13 can be buckled on the femur; the femoral condyle prosthesis and the femur can be firmly and reliably fixed, and can withstand long-term test.

[0096] In a preferred embodiment, the femoral condyle prosthesis has a small surface area, and thus has small volume and weight; specifically, the area of the outer surface of the medial femoral condyle prosthesis 101 is less than 60% of the outer surface area of the medial femoral condyle, and preferably is about 40%-55%, and preferably is about 50% in the present application; similarly, the area of the outer surface of the lateral femoral condyle prosthesis 102 is less than 60% of the outer surface area of the lateral femoral condyle, and preferably is about 40%-55%, and preferably is about 50% in the present application.

[0097] The medial femoral condyle prosthesis 101 and the lateral femoral condyle prosthesis 102 are respectively located on the two sides of the femoral trochlea, and the replacement of the medial femoral condyle prosthesis 101 and the lateral femoral condyle prosthesis 102 does not affect the normal work of the femoral trochlea, so the replacement of the medial femoral condyle prosthesis 101 and the lateral femoral condyle prosthesis 102 does not affect the normal work and installation position of the patella.

[0098] Preferably, the tibial plateau prosthesis includes a medial tibial plateau prosthesis 201 and a lateral tibial plateau prosthesis 202, the medial tibial plateau prosthesis 201 and the lateral tibial plateau prosthesis 202 are respectively arranged on the two sides of the intercondylar ridge 31 of the tibial plateau, and are located below the femoral condyle prosthesis 1, the tibial plateau prosthesis 2 replaces the medial tibial plateau and the lateral tibial plateau in the tibial plateau, and supports the femoral condyle prosthesis 1. Figure 9 In order to place and fix the two tibial plateau prostheses, the tibia or the tibial plateau needs to be reformed in structure, and the reformed tibia or tibial plateau is shown in FIG. Figure 10 When only the medial tibial plateau prosthesis 201 or the lateral tibial plateau prosthesis 202 of the tibial plateau prosthesis is replaced, the reformed tibia or tibial plateau is shown in FIG.

[0099] The upper surface of the tibial platform prosthesis 2 is concave inward and downward to facilitate the cooperation with the femur, similar to the medial and lateral platforms on the natural tibial platform, as shown in Figure 1 .

[0100] The cross section of the tibial platform prosthesis 2 is in the shape of a waist or a waist-like shape, and the outer contour is consistent with the excavated part of the tibial platform.

[0101] The cross section of the tibial platform prosthesis 2 is about one third of the cross section of the tibial platform.

[0102] In a preferred embodiment, as shown in Figure 1 , the artificial knee joint further comprises a positioning pin 5 for fixing the tibial platform prosthesis 2, and the medial tibial platform prosthesis 201 and the lateral tibial platform prosthesis 202 are fixed to the tibia through the positioning pin 5.

[0103] Preferably, the positioning pin 5 penetrates the intercondylar ridge 31 of the tibial platform, and one end is mounted in the medial tibial platform prosthesis 201, and the other end is mounted in the lateral tibial platform prosthesis 202;

[0104] In a preferred embodiment, as shown in Figure 7 , a prosthesis slot 23 is formed in the bottom of the tibial platform prosthesis 2,

[0105] A tibial slot 32 is formed in the top of the tibia below the tibial platform; that is, a tibial slot 32 is formed in the tibia / tibial platform below the tibial platform, and the tibial slot 32 penetrates / penetrates into the intercondylar ridge 31 of the tibial platform; that is, an intercondylar ridge hole 33 is formed in the intercondylar ridge, and the intercondylar ridge hole 33 is a through hole; as shown in Figure 9 and Figure 10 .

[0106] The prosthesis slot 23 corresponds to the tibial slot 32, and together with the intercondylar ridge hole 33, they form a limiting hole 4 for mounting the positioning pin 5; as shown in Figure 4 , Figure 5 and Figure 6 .

[0107] Preferably, the limiting hole 4 and the positioning pin 5 penetrate the intercondylar ridge 31 of the tibial platform, and communicate the medial tibial platform prosthesis 201 and the lateral tibial platform prosthesis 202; that is, in the axial direction of the limiting hole 4, the limiting hole is spliced by three parts, of which the two parts at both ends are surrounded by the prosthesis slot 23 above and the tibial slot 32 below; the third part in the middle is the intercondylar ridge hole 33 formed on the intercondylar ridge 31 of the tibial platform.

[0108] In a preferred embodiment, the length of the positioning pin is greater than the length of the prosthetic slot 23 on the medial tibial plateau prosthesis 201 or the lateral tibial plateau prosthesis 202, and the length of the positioning pin is less than the sum of the length of the prosthetic slot 23 and the width of the intercondylar ridge 31. Thus, when only the medial tibial plateau prosthesis 201 or the lateral tibial plateau prosthesis 202 is installed, the positioning pin can achieve the positioning and fixing effect. When the medial tibial plateau prosthesis 201 and the lateral tibial plateau prosthesis 202 are installed, the length of the limiting hole 4 is naturally extended, the positioning pin can further move into the extended limiting hole, and finally the positioning pin completely penetrates the intercondylar ridge 31 of the tibial plateau, and the two ends of the positioning pin are embedded in the prosthetic slot 23, achieving the limiting and fixing effect of the tibial plateau prosthesis 2. It is worth noting that due to the presence of the positioning pin, the medial tibial plateau prosthesis 201 and the lateral tibial plateau prosthesis 202 on both sides of the intercondylar ridge of the tibial plateau can be positioned in the vertical direction, so that the physiological height of the replaced knee femur is basically consistent with the physiological height of the replaced knee femur, and the fixation of the medial tibial plateau prosthesis 201 and the lateral tibial plateau prosthesis 202 is performed on this basis, so that the tibial prosthesis is in a reasonable position, ensuring that the patient experiences good after surgery.

[0109] When only the medial tibial plateau prosthesis 201 or the lateral tibial plateau prosthesis 202 of the tibial plateau prosthesis 2 is installed, the limiting hole extends into the intercondylar ridge 31 of the tibial plateau and does not penetrate the intercondylar ridge 31 of the tibial plateau, i.e. the intercondylar ridge hole 33 at this time is a blind hole.

[0110] Preferably, the width of the intercondylar ridge 31 of the tibial plateau is less than or equal to the length of the prosthetic slot 23.

[0111] In a preferred embodiment, as shown in Figure 4 、 Figure 5 and Figure 6 , the cross-sectional shape of the limiting hole 4 is consistent with the cross-sectional shape of the positioning pin 5; the cross-sectional shape can be oval, square, trapezoidal, diamond, triangular, pentagonal, pentagonal star, hexagonal, octagonal, etc. Among various cross-sectional shapes of the positioning pin, triangular, square, trapezoidal and polygonal are better in use effect, and trapezoidal is preferably selected in the present application, and the upper base of the trapezoidal shape is located in the prosthetic slot 23, the lower base is located in the tibial slot 32, and the length of the upper base is greater than the length of the lower base.

[0112] In a preferred embodiment, the cross-sectional size of the positioning pin corresponds to the cross-sectional size of the limiting hole, and the two are tightly fitted, preferably with an interference fit; so that the positioning pin is difficult to continue to stretch in after being embedded to a certain depth and is stuck, at this time the positioning pin is just stopped at the desired position, preferably the central position, without deviating to both sides;

[0113] In a preferred embodiment, the cross-sectional dimension of the positioning hole and the cross-sectional dimension of the positioning hole correspond, the positioning pin can be embedded in the corresponding depth position of the positioning hole, and an expansion bolt can be arranged on the end face of the positioning pin, when the positioning pin is located at the desired position, preferably the center position, the expansion bolt is screwed to fix the positioning pin in the positioning hole, so as to ensure that the position of the positioning pin is stable and cannot deviate to both sides.

[0114] In a preferred embodiment, the cross-sectional dimension of the positioning hole and the cross-sectional dimension of the positioning hole correspond, the positioning pin can be embedded in the corresponding depth position of the positioning hole, and an expansion bolt can be arranged on the end face of the positioning pin, when the positioning pin is located at the desired position, preferably the center position, the expansion bolt is screwed to fix the positioning pin in the positioning hole, so as to ensure that the position of the positioning pin is stable and cannot deviate to both sides.

[0115] In the present application, the positioning pin has one or more, each positioning pin is matched with a positioning hole, when the positioning pin has multiple, the positioning hole also has multiple, the number of positioning pins is consistent with the number of positioning holes.

[0116] The tibial platform prosthesis 2 is placed at the front upper end surface position of the tibia, below the posterior side of the patella, preferably, the setting position of the tibial platform prosthesis 2 maintains a predetermined distance from the lower edge of the patella, and the distance value between the natural tibial platform and the patella is equal to the predetermined distance value; replacing the natural tibial platform with the tibial platform prosthesis 2 has no substantial impact on the patella itself and does not affect the sliding of the patella, which can ensure that the patella is retained after the operation. The natural tibial platform in the present application refers to the tibial platform naturally grown in the human body, wherein natural means naturally existing.

[0117] In a preferred embodiment, as shown in Figure 7 and Figure 8 , the inner condyle prosthesis 201 and the tibial platform lateral prosthesis 202 are substantially mirror-symmetric in large structure, but the size of each component is slightly different, and are completely copied according to the physiological structure of the human body; the inner condyle prosthesis 201 and the tibial platform lateral prosthesis 202 both include an upper gasket 21 and a lower gasket 22, and the upper gasket 21 and the lower gasket 22 are fixed by bolts, pins and the like, so that the upper gasket 21 and the lower gasket 22 can have a certain relative displacement in the vertical direction, and cannot move relatively in other directions.

[0118] An elastic member 6 is arranged on the lower pad 22. The elastic member 6 buffers the impact force transmitted from the femoral condyle prosthesis 1 to the upper pad 21 of the tibial plateau prosthesis 2, so that the upper pad 21 has a semi-meniscus function. Specifically, when the femoral condyle prosthesis 1 transmits an impact force to the tibial plateau prosthesis 2, the impact force is first received by the upper pad 21, and the upper pad 21 moves downward to press the elastic member 6. As the reaction force of the elastic member 6 gradually increases, the speed of the downward movement of the upper pad 21 gradually decreases, and the impact force on the upper pad 21 gradually decreases. Finally, the upper pad 21 is pressed against the lower pad, and the impact force is transmitted to the tibia. Since the impact force is buffered by the elastic member 6, the damage to the tibia can be ignored, so that the buffering effect similar to that of the semi-meniscus is achieved, that is, the upper pad 21 has a semi-meniscus function.

[0119] In the present application, the elastic member 6 can include a spring, an air bag, a cushion pad or other elastic member having a certain buffering effect. The elastic member is arranged below the upper pad 21 and can buffer the impact force transmitted by the upper pad 21. The specific placement position can be selected according to the specific structure.

[0120] In the following, the elastic member including a spring is taken as an example for description.

[0121] The elastic member 6 penetrates and is fixed on the lower pad 22, and the part of the elastic member 6 above the lower pad 22 is in contact with the lower surface of the upper pad 21, and the part of the elastic member 6 below the lower pad 22 is in a columnar shape.

[0122] Preferably, as shown in FIG. 6, the elastic member 6 includes a sleeve 61 and a spring 62. Figure 8

[0123] The lower end of the spring 62 is embedded in the sleeve 61, and the upper end of the spring 62 is in contact with the lower surface of the upper pad 21. Thus, the force transmitted from the femoral condyle prosthesis to the upper pad 21 is buffered by the spring 62 and then acts on the lower pad 22.

[0124] In the present application, the prosthesis slot 23 is arranged on the lower pad 22.

[0125] In a preferred embodiment, the sleeve 61 is embedded in the hole cavity 7 arranged on the tibia 3. Preferably, the cross-sectional shape and size of the hole cavity are consistent with those of the sleeve 61, and the sleeve 61 can be tightly fitted in the hole cavity 7, so that the relative position between the tibia and the tibial plateau prosthesis is stable and there is no relative displacement. The cross-sectional shape of the sleeve 61 and the hole cavity 7 can be various shapes, such as polygon, quadrilateral, triangle, ellipse, circle and the like. Preferably, the cross-sectional shape is circular. ​

[0126] The sleeve can protect the spring and limit and fix the tibial plateau prosthesis 2, so that the tibial plateau prosthesis 2 has a simple structure and the fixing process is simplified.

[0127] Preferably, the spring 62 is always in a non-stretched state,

[0128] In a preferred embodiment, as shown in Fig. Figure 8 A bolt 63 is arranged at the bottom of the sleeve 61 and can move in the vertical direction by rotating, and the top of the bolt is in contact with the bottom of the spring 62 inside the sleeve 61, so that the elasticity of the spring 62 can be adjusted by controlling the position of the bolt 63 in the vertical direction; when the bolt 63 moves upward in the vertical direction, the spring 62 is compressed, the elasticity of the spring 62 increases, and when the bolt 63 moves downward in the vertical direction, the compression degree of the spring 62 decreases, and the elasticity of the spring 62 decreases; so that the appropriate spring elasticity, or spring tightness, can be adjusted according to the age and physical condition of the patient, so that the elasticity between the upper gasket 21 and the lower gasket 22 is consistent with the elasticity of the meniscus, and the total height / thickness of the upper gasket 21 and the lower gasket 22 is consistent with the height of the side of the artificial knee joint that has not been replaced,

[0129] The total height / thickness of the upper gasket 21 and the lower gasket 22 of the medial tibial plateau prosthesis 201 or the lateral tibial plateau prosthesis 202 can also be consistent with the height of the previously replaced lateral tibial plateau prosthesis 202 or medial tibial plateau prosthesis 201, so that the height and elasticity inconsistency between the medial tibial plateau prosthesis 201 and the lateral tibial plateau prosthesis 202 replaced in two times is solved, and the effect after batch surgery is good.

[0130] In a preferred embodiment, a scale line is engraved near the bottom of the sleeve 61 and / or the bolt 63, so that the screwing degree of the bolt 63 can be directly read through the scale line; so as to facilitate the adjustment of the spring tightness when the elastic member 6 is installed.

[0131] Preferably, the spring 62 comprises a top block arranged at the top to contact the upper gasket 21.

[0132] In the present application, the spring 62 can be made of metal, various high molecular polymers and other materials.

[0133] The present application provides a use method of an artificial knee joint,

[0134] The artificial knee joint is the artificial knee joint described above, and the method comprises the following steps:

[0135] Step 1, a space for placing the tibial platform prosthesis 2 is opened on the tibial platform, preferably, the space is only one time, located on one side of the intercondylar ridge 31 of the tibial platform, the space is two times, located on both sides of the intercondylar ridge 31 of the tibial platform, and in the process of opening the space, there is no damage to the intercondylar ridge 31 and the cruciate ligament thereon, and further preferably, there is no damage to the patella and the quadriceps tendon thereon;

[0136] Step 2, a tibial slot 32 is excavated on the tibia and extended to the intercondylar ridge 31 of the tibial platform to form an intercondylar ridge hole 33 on the intercondylar ridge 31 of the tibial platform; a hole cavity 7 is excavated on the tibia; preferably, the number of tibial slots 32 and hole cavities 7 is not fixed, which can be one, two or more, and preferably one is selected;

[0137] Step 3, the sleeve on the tibial platform prosthesis 2 is embedded into the hole cavity 7, and the relative positions of the prosthesis slot 23, the tibial slot 32 and the intercondylar ridge hole 33 are adjusted, so that the prosthesis slot 23 and the tibial slot 32, and the intercondylar ridge hole 33 together form a limiting hole 4;

[0138] Step 4, the positioning pin 5 is installed into the limiting hole 4;

[0139] Step 5, the height position of the tibial platform prosthesis 2 is fixed by the positioning pin 5, and the height of the tibial platform prosthesis 2 is further fixed by adjusting the amount of bone cement injection.

[0140] Preferably, before step 3 is performed, the tightness of the spring 62 is adjusted by rotating the bolt 63, and the tightness / strength of the spring is detected by using an elastic detection device to ensure that the tightness / strength of the springs in the plurality of elastic members 6 is consistent;

[0141] Preferably, the following optional steps are further included:

[0142] Step a, the upper gasket 21, the lower gasket 22 and the elastic member 6 are assembled into a complete tibial platform prosthesis 2, preferably, the tibial platform prosthesis 2 includes a medial tibial platform prosthesis 201 and / or a lateral tibial platform prosthesis 202;

[0143] Step b, the femoral condyle prosthesis 1 is installed, wherein the femoral condyle prosthesis is fixed on the femur and is in contact with the tibial platform prosthesis above the tibial platform prosthesis; preferably, a prosthesis fixing area is first excavated on the femur, then the femoral condyle prosthesis is embedded into the area, and due to the special curvature of the femoral condyle prosthesis and the front cover 11 and the rear cover 13, the femoral condyle prosthesis is buckled on the femur, at the same time, the fixing spike 12 on the femoral condyle prosthesis is inserted into the cancellous bone of the femur, and the fixing pin 14 on the femoral condyle prosthesis is embedded into the fixing pin 14 excavated on the femur, thereby realizing the fixation between the femoral condyle prosthesis and the femur.

[0144] The present application provides a method for artificial knee joint replacement,

[0145] The artificial knee joint is the artificial knee joint as described above, and the method comprises the following steps:

[0146] Step 1: a space for placing the tibial platform prosthesis 2 is formed on the tibial platform, preferably, when there is only one space, the space is located on one side of the intercondylar ridge 31 of the tibial platform, and when there are two spaces, the spaces are respectively located on both sides of the intercondylar ridge 31 of the tibial platform, and in the process of forming the space, the intercondylar ridge 31 and the cruciate ligament thereon are not damaged, and further preferably, the patella and the quadriceps tendon thereon are not damaged;

[0147] Step 2: a tibial slot 32 is excavated on the tibia and extended to the intercondylar ridge 31 of the tibial platform to form an intercondylar ridge hole 33 on the intercondylar ridge 31 of the tibial platform; a hole cavity 7 is excavated on the tibia; preferably, the number of the tibial slot 32 and the hole cavity 7 is not fixed, which can be one, two or more, and preferably one is selected;

[0148] Step 3: the sleeve on the tibial platform prosthesis 2 is embedded into the hole cavity 7, and the relative positions of the prosthesis slot 23, the tibial slot 32 and the intercondylar ridge hole 33 are adjusted so that the prosthesis slot 23, together with the tibial slot 32 and the intercondylar ridge hole 33, forms a limiting hole 4;

[0149] Step 4: the positioning pin 5 is installed into the limiting hole 4;

[0150] Step 5: the height position of the tibial platform prosthesis 2 is fixed by the positioning pin 5, and the height of the tibial platform prosthesis 2 is further fixed by adjusting the amount of injected bone cement.

[0151] Preferably, before step 3 is performed, the tightness of the spring 62 is adjusted by rotating the bolt 63, and the tightness / strength of the spring is detected by using an elastic detection device to ensure that the tightness / strength of the springs in the plurality of elastic members 6 is consistent;

[0152] Preferably, the following optional steps are further included:

[0153] Step a: the upper gasket 21, the lower gasket 22 and the elastic member 6 are assembled into a complete tibial platform prosthesis 2, preferably, the tibial platform prosthesis 2 comprises a tibial platform medial prosthesis 201 and / or a tibial platform lateral prosthesis 202;

[0154] Step b, installing femoral condyle prosthesis 1, wherein the femoral condyle prosthesis is fixed on the femur and is above the tibial plateau prosthesis and in contact with the tibial plateau prosthesis; preferably, first, a prosthesis fixing area is excavated on the femur, then the femoral condyle prosthesis is embedded into the area, and due to the special curvature and front cover 11 and rear cover 13 of the femoral condyle prosthesis, the femoral condyle prosthesis is buckled on the femur, at the same time, the fixing spikes 12 on the femoral condyle prosthesis are inserted into the cancellous bone of the femur, and the fixing pins 14 on the femoral condyle prosthesis are embedded into the fixing pins 14 excavated on the femur, thereby realizing the fixation between the femoral condyle prosthesis and the femur.

[0155] The above describes the present application in combination with the preferred embodiments, but these embodiments are only exemplary and are only for the purpose of illustration. On this basis, various substitutions and improvements can be made to the present application, and these all fall within the protection scope of the present application.

Claims

1. An artificial knee joint, characterized in that, The knee joint includes a femoral condyle prosthesis (1) and a tibial plateau prosthesis (2). The tibial plateau prosthesis (2) includes a medial tibial plateau prosthesis (201) and a lateral tibial plateau prosthesis (202), which are independent of each other. The medial tibial plateau prosthesis (201) and the lateral tibial plateau prosthesis (202) are respectively located on both sides of the intercondylar ridge (31) of the tibial plateau and below the femoral condyle prosthesis (1); The tibial plateau prosthesis (2) is placed below the posterior side of the patella; The artificial knee joint also includes a positioning pin (5), through which the medial tibial plateau prosthesis (201) and the lateral tibial plateau prosthesis (202) are fixed to the upper end of the tibia; Prosthesis notches (23) are provided at the bottom of the inner prosthesis (201) and the outer prosthesis (202) of the tibial plateau. A tibial notch (32) is provided at the top of the tibia below the tibial plateau prosthesis (2); The prosthesis notch (23) together with the tibial notch (32) forms a limiting hole (4) for installing the positioning pin (5), and the limiting hole penetrates the intercondylar ridge (31) of the tibial plateau.

2. The artificial knee joint according to claim 1, characterized in that, The positioning pin (5) passes through the intercondylar ridge (31) of the tibial plateau, with one end of its upper part installed in the medial prosthesis (201) of the tibial plateau and the other end of its upper part installed in the lateral prosthesis (202) of the tibial plateau.

3. The artificial knee joint according to claim 1, characterized in that, The medial tibial plateau prosthesis (201) and the lateral tibial plateau prosthesis (202) each include an upper pad (21) and a lower pad (22). Among them, an elastic member (6) is provided on the lower pad (22). The elastic member (6) buffers the impact force transmitted from the femoral condyle prosthesis (1) to the upper pad of the tibial plateau prosthesis (2), so that the upper pad (21) has a meniscus-like function.

4. The artificial knee joint according to claim 3, characterized in that, The elastic member (6) passes through the lower pad (22) and is fixedly installed on the lower pad (22). Its upper end extends above the lower pad (22) and rests on the lower surface of the upper pad.

5. The artificial knee joint according to claim 4, characterized in that, The elastic member (6) includes a sleeve (61) and a spring (62), with the lower end of the spring (62) embedded in the sleeve (61) and the upper end of the spring resting on the lower surface of the upper washer. The sleeve (61) passes through the lower gasket (22), and the bottom end of the sleeve is installed in the cavity (7) on the tibia.

6. The artificial knee joint according to claim 5, characterized in that, A bolt (63) for adjusting the tension of the spring (62) is provided at the bottom of the sleeve (61).

Images