CN204709085U - The two slip artificial knee joint of a kind of high-molecular organic material - Google Patents

Abstract

A double-sliding artificial knee joint made of organic polymer materials, comprising femoral condyle and tibial support of polyetheretherketone (PEEK) or its derivatives and tibial liner of ultra-high molecular weight polyethylene (UHMWPE), wherein the tibial support includes a platform and The stabilizing wing positioning part has a certain section, and the stabilizing wing positioning part is arranged under the platform and is perpendicular to it; the upper end and the lower end of the tibial pad are respectively engaged with the femoral condyle and the tibial support platform; the tibial pad is a double sliding tibial pad, and the femoral The sliding surface of the condyle on the tibial liner and the sliding surface of the tibial tray on the tibial liner are smooth sliding surfaces. All implant parts of the structure of the utility model do not contain metal materials, and there is no allergy problem caused by metal and its corrosion; the elastic modulus of PEEK matches the natural bone, which reduces the problem of stress shielding; The primary sliding friction surface reduces the wear problem; the potential wear problem of the secondary sliding interface between the PEEK tibial tray and the UHMWPE tibial liner is further reduced.

Description

An organic polymer double-sliding artificial knee joint

technical field

The utility model relates to a medical rehabilitation device, in particular to a double-sliding artificial knee joint made of organic polymer materials.

Background technique

Since the 1980s, double-sliding artificial knee replacements have been widely used clinically (LaCour MT, Sharma A, Carr CB, Komistek RD, Dennis DA. (2014) Confirmation of long-term in vivo bearing mobility in eight rotating- platformTKAs. Clin Orthop Relat Res. 2014 Sep;472(9):2766-73). Compared with the traditional single-sliding knee joint design, the double-sliding design has the advantages of low contact stress, small internal and external rotation resistance, and automatic reset. The double-sliding artificial knee joints that have been clinically used at present all use the combination of cobalt-chromium-molybdenum (CoCrMo) alloy and ultra-high molecular weight polyethylene (UHMWPE). The femoral condyle and tibial tray (tibial plateau) were constructed of CoCRMo alloy, and the rotatable or slidable tibial liner was constructed of ultra-high molecular weight polyethylene.

Metal materials, especially CoCrMo alloys, have unsatisfactory clinical problems whether they are applied to femoral condyles or tibial trays. First, the wear problem of ultra-high molecular weight polyethylene tibial liner on the main sliding surface of CoCrMo femoral condyle (Kinney MC, Kamath AF. (2013) Osteolyticpseudotumor after cemented total knee arthroplasty. Am J Orthop (BelleMead NJ). 2013Nov; 42( 11):512-4); Second, the wear problem of ultra-high molecular weight polyethylene tibial liner on the sliding surface of CoCrMo tibial tray (Banerjee S, Cherian JJ, Bono JV, Kurtz SM, Geesink R, Meneghini RM, Delanois RE ,Mont MA.(2014)GrossTrunnion Failure After Primary Total Hip Arthroplasty.J Arthroplasty.2014Nov 26.pii:S0883-5403(14)00899-7); CoCrMo femoral condyle to natural bone stress shielding problem (Panegrossi G, Ceretti M ,Papalia M,Casella F,Favetti F,Falez F.(2014) Bone loss management in total knee revision surgery.Int Orthop.2014Feb;38(2):419-27); Third, the effect of CoCrMo tibial support on natural bone Stress shielding problem (Panegrossi G, Ceretti M, Papalia M, Casella F, Favetti F, Falez F.(2014) Bone loss management in total knee revision surgery. Int Orthop.2014Feb;38(2):419-27); Fourth, the CoCrMo alloy contains a small amount of nickel, which causes allergic reactions in some patients (Innocenti M, Carulli C, Matassi F, Carossino AM, Brandi ML, Civinini R. (2014) Total knee arthritis in patients with hypersensitivity tometals.Int Orthop. 2014Feb; 38(2):329-33.doi:10.1007/s00264-013-2229-2); fifth, metal materials are not Corrosion can be avoided, Co, Cr, Mo, Ni plasma are released, and excessive metal ion release can cause toxicity (Kretzer JP, Reinders J, Sonntag R, Hagmann S, Streit M, Jeager S, Moradi B. (2014) Wear in total knee arthritis--just a question of polyethylene? :Metal ion release in total knee arthritis.Int Orthop.2014Feb; 38(2):335-40.doi:10.1007/s00264-013-2162-4.Epub 2013Nov 12.); Sixth, metal materials, especially CoCrMo Impact on magnetic resonance (MRI) imaging (Bachschmidt TJ, Sutter R, Jakob PM, Pfirrmann CW, Nittka M. (2014) Knee implant imaging at 3 Tesla using high-bandwidth radiofrequency pulses. J Magn Reson Imaging. 2014Aug 2000/m1: 10. 24729.[Epub ahead of print]).

As early as the 1990s, British doctors and scientists tried the clinical application of single-sliding total knee replacement made of organic polymer materials (Plante-Bordeneuve P, Freeman MA. (1993) Tibial high-density polyethylene wear in conforming tibiofemoral prostheses. J Bone Joint Surg Br. 1993 Jul; 75(4):630-6.). The femoral condyle is made of Polyacetal (Delrin) polymer material, and the tibial friction surface is made of ultra-high molecular weight polyethylene. The fixation between the Polyacetal femoral condyle and the natural bone is fixed by bone cement or extrusion without bone cement. The components are fixed with bone cement to the natural bone. Ten years of clinical follow-up found that Polyacetal had no abnormal wear on the UHMWPE friction surface, and Polyacetal had no mechanical damage to the femoral condyle. The main problems caused by revision were loosening and early infection (Bradley GW, Freeman MA, Tuke MA, McKellop HA .(1993)Evaluation of wear in an all-polymer total knee replacement.Part 2:clinicalevaluation of wear in a polyethylene on polyacetal total knee.Clin Mater.1993;14(2):127-32;McKellop HA, T, Bradley G.(1993)Evaluation of wear in an all-polymer total knee replacement.Part 1:laboratory testing of polyethylene on polyacetal bearing surfaces.Clin Mater.14(2):117-26;Moore DJ,Freeman MA, Revell PA, Bradley GW, Tuke M. (1998) Can a total knee replacement prosthesis be made entirely of polymers? J Arthroplasty. 13(4):388-95). The clinical use of Polyacetal as a femoral condyle was discontinued due to the poor chemical stability of Polyacetal after gamma ray sterilization.

In recent years, a new generation of polymer material polyetheretherketone (PEEK) with high chemical stability, high strength and high biocompatibility has been widely used in orthopedic implants, especially for spinal fixation and fusion. Since 2010, American scientists and researchers have discovered that high-strength and high-stability PEEK polymer materials have better wear resistance than CoCrMo alloys on UHMWPE acetabular cup liners as the friction surface of the femoral head of the hip joint. Sex (Wang AG, Zhang ZT, Lawrynowicz DE and Yau SS(2010) Orthopedic PAEK-on-polymer bearings, HOWMEDICA OSTEONICS CORP, IPC8Class: AA61F230FI, USPC Class: 6231811, Patent application number: 20100312348-, 2010-1ingh; V, Ogden, C, Sitton, K and Sitton, K (2012) Wear evaluation of different polymeric materials for total discreplacement (TDR), Proceedings of the ASME/STLE International Joint Tribology Conference, Los Angeles, CA, 2011, 35-37, 2012).

Although the above studies have proposed the concept of PEEK on polyethylene sliding surface, the friction of PEEK on polyethylene sliding surface is only suitable for articular surfaces with good matching and low surface contact stress, such as ball-and-socket hip joints (wear Quantity: 16.5±1.8mm ³ /million, WangAG, Zhang ZT, Lawrynowicz DE and Yau SS(2010) Orthopedic PAEK-on-polymer bearings, HOWMEDICA OSTEONICS CORP, IPC8Class: AA61F230FI, USPC Class: 623-1811, Patent application number: 2031003 ,2010-12-09). Moreover, the low wear of PEEK on the high molecular weight polyethylene on the hip joint cannot be directly reflected in the knee joint. Due to the requirements of different sports and the impact force far greater than that of the hip joint, the surface shape of the knee joint is very complex and the matching degree Relatively poor, which will cause the knee joint surface pressure (10 ~ 20MPa) is much higher than the hip joint (2 ~ 5MPa). The coupling of these harsher mechanical environments and the higher rigidity of the metal tibial tray results in substantially increased wear. According to the ISO14243 standard test, the wear of the PEEK femoral condyle to the high molecular weight polyethylene liner can reach 18.0±3.0mm ³ /million, which is higher than the wear of the currently used CoCrMo to polyethylene (9.0±4.0mm ³ /million, Fisher J , Jennings LM, Galvin AL, Jin ZM, Stone MH, Ingham E. (2010) Knee Society Presidential Guest Lecture: Polyethylene wear in total knees. Clin Orthop Relat Res. 2010 Jan; 468(1): 12-8. doi: 10.1007 /s11999-009-1033-1.Epub 2009Aug 11), which further proves why the clinically applied knee prostheses are all made of metal materials, especially CoCrMo alloys.

In response to the above problems, we have done a lot of experiments, and through further treatment of the friction surface of the PEEK femoral condyle on the high molecular weight polyethylene liner, the friction situation has been improved to some extent, but the desired result has not yet been achieved. The results of the above tests were almost the same whether the metal tibial tray was used or the high molecular weight polyethylene was used as the liner and fixed directly on the tibia with bone cement.

Further, our research found that, according to the principle of tribology, under high-intensity exercise load, joint wear has a certain conduction transfer effect, and it should be possible to further optimize the tibial tray to reduce this impact load, and indirectly reduce the PEEK femoral condyle. Abrasion against high molecular weight polyethylene liners. However, due to the structural characteristics of the knee joint, the tibial tray bears the greatest load. No matter in clinical practice or in the literature, it has never been used or mentioned that other materials can be used for the tibial tray. Therefore, the key of the utility model is whether this alternative material can be found to meet the requirements of strength, impact load reduction and wear reduction at the same time, so that the whole artificial knee joint system is better than the current all-metal materials, especially the artificial CoCrMo alloy. knee joint.

Utility model content

The utility model proposes a double-sliding artificial knee joint made of organic polymer material for the first time, which includes the femoral condyle, tibial liner and tibial support, wherein the femoral condyle and tibial support are made of PEEK or its derivative materials, and the tibial liner is made of high Made of molecular weight polyethylene material. Because the knee joint structure of the utility model creatively adopts the tibial bracket of PEEK or its derivative material, it is possible to apply the PEEK femoral condyle to the high molecular weight polyethylene tibial liner in the knee joint system. In the utility model, through the matching of material properties between the polyethylene tibial liner and the PEEK tibial support, the cushioning of the two sliding surfaces of the PEEK femoral condyle to the polyethylene tibial liner and the PEEK tibial support to the polyethylene tibial liner is increased, Controlling the displacement between the two affects the wear mechanism of the PEEK femoral condyle on the high molecular weight polyethylene tibial liner. In addition, the PEEK tibial tray can effectively transmit the motion load, so that the gap between the PEEK femoral condyle and the polyethylene tibial liner The primary sliding and secondary sliding movement between the PEEK tibial tray and the polyethylene tibial liner are matched to reduce the alternating shear caused by multi-directional movement, which can greatly reduce the overall wear of the two surfaces of the polyethylene liner. According to the ISO14243 standard test, the wear amount is reduced to 4.3±1.1mm ³ /million, which is much better than the wear amount of the currently used CoCrMo on polyethylene (9.0±4.0mm ³ /million), so it can be predicted that the knee joint based on wear The life span can reach more than 40 years from the current 20 years. This fully provides the possibility of clinical application of the total knee joint system based on PEEK material.

In addition, the utility model reduces the clinical problems caused by the use of metal materials, such as the sensitivity of metal ions, toxicity, pseudo-tumor and other problems and because the elastic modulus (3GPa) of PEEK material is far lower than that of metal (200GPa) It is similar to the elastic modulus of bone (0.8 ~ 17GPa), so the use of PEEK tibial tray can reduce the stress shielding of the tibia, avoid bone resorption, so as to achieve a long-term good fixation effect of more than 30 years; these advantages will make full polymer polymerization The knee joint system composed of materials can be widely used in different patients, especially young patients, without clinical revision; this can not only reduce the pain of patients, but also greatly reduce medical costs. In addition, the utility model further solves the clamping problem in the polymer prosthesis in order not to damage the polymer prosthesis, and solves the problem of clinical practical use. problems in order to observe the surgical effect and the long-term service of the prosthesis in the human body.

In order to realize the purpose of above-mentioned utility model, the utility model adopts following technical scheme:

A double-sliding artificial knee joint made of organic polymer materials, including femoral condyle, tibial liner and tibial tray, wherein:

The tibial support includes a tibial support platform and a stabilizing wing positioning part, and the stabilizing wing positioning part is arranged below the tibial support platform and perpendicular to the tibial support platform; the lower end of the femoral condyle is in contact with the tibial pad The upper end is engaged; the lower end of the tibial pad is engaged with the tibial tray platform; the femoral condyle, the tibial pad, and the tibial tray are all made of polymer materials, wherein the femoral condyle and the tibial tray Composed of polyetheretherketone or its derivatives, the tibial liner is composed of ultra-high molecular weight polyethylene; the tibial liner is a double-sliding tibial liner, wherein the femoral condyle is opposed to the sliding surface of the tibial liner The sliding surfaces of the tibial tray and the tibial liner are smooth sliding surfaces.

Further, the surface roughness of the sliding surface is not greater than 1.0 μm.

Further, the surface roughness of the sliding surface is less than 0.1 μm.

Further, the left and right sides of the femoral condyle are provided with clamping grooves; the clamping grooves contain metal or ceramic reinforcements matching their shapes; the upper end sidewall of the tibial tray platform contains one or more metal strip-shaped components.

Further, the junction of the outer end of the stabilizing wing positioning part and the platform of the tibial tray includes a metal reinforcement part.

Further, the metal reinforcement, the metal strip-shaped part and the metal reinforcement are all made of biocompatible metals or alloys thereof; the metals or alloys thereof include cobalt-chromium-molybdenum alloys, titanium or titanium alloys, Tantalum or tantalum alloys, stainless steel, and zirconium-niobium alloys.

Further, the stabilizing wing positioning part is provided with a hollow fixing column perpendicular to the tibial support platform, and the opening of the hollow fixing column is set on the upper surface of the tibial support platform; or the upper surface of the platform A raised swivel column is arranged on the top.

Further, the lower part of the tibial pad is provided with a cylindrical or conical rotating column; or the lower part of the tibial pad is provided with an inward concave cavity.

Further, the hollow fixing column is matched with the cylindrical or conical rotating column; the raised rotating column is matched with the concave cavity.

Further, the femoral condyle, the tibial liner and the tibial tray can be combined and disassembled flexibly.

Owing to adopting above technical scheme, the beneficial effect of the utility model is:

1) All implant parts of the organic polymer material double-sliding artificial knee joint provided by the utility model do not contain metal materials, and there is no metal corrosion and allergy problems that may be caused by metals;

2) The elastic modulus of PEEK in the utility model matches the natural bone, which reduces the problem of stress shielding;

3) In the utility model, the sliding surface of the PEEK femoral condyle to the UHMWPE tibial liner reduces the wear problem;

4) In the utility model, the potential wear problem of the PEEK tibial support on the sliding surface of the UHMWPE tibial liner is further reduced;

5) In the present utility model, all implant parts composed of organic polymer materials do not interfere with nuclear magnetic resonance imaging.

Description of drawings

Fig. 1 is a structural schematic view of the joining of components of the organic polymer material double-sliding artificial knee joint provided by the present invention;

Fig. 2 is a structural schematic diagram of the components of the double-sliding artificial knee joint made of organic polymer materials in an embodiment of the utility model;

Fig. 3 is a schematic diagram of the components of the double-sliding artificial knee joint made of organic polymer materials in another embodiment of the present invention.

Fig. 4 is the plan view of femoral condyle among the utility model, and it has shown the structural representation of metal inlay on both sides of femoral condyle;

Fig. 5 is a schematic structural view of the upper side wall of the tibial support platform inlaid with a metal band-shaped part in the utility model;

Fig. 6 is a sectional view of the structure of Fig. 5 of the utility model;

Explanation of reference signs

1 femoral condyle, 2 tibial liner, 21 cylindrical or cone-shaped rotating column, 3 tibial tray, 31 hollow fixed column, 32 raised rotating column, 4 tibial tray platform, 5 stabilizer wing positioning part, 11 metal inlay objects, 12 metal inlays, 33 metal bands.

Detailed ways

In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model, and are not intended to limit the utility model.

As shown in Figures 1, 2 and 3, a kind of organic polymer material double-sliding artificial knee joint provided by the utility model includes a femoral condyle 1, a tibial pad 2 and a tibial support 3, wherein the tibial support 3 includes a tibial support platform 4 And the stabilizing wing positioning part 5 with a certain cross section, the stabilizing wing positioning part 5 is arranged below the tibial support platform 4 and perpendicular to the tibial support platform 4, and is used to fix the tibial support 3 and then the whole artificial knee joint on the human skeleton The lower end of the femoral condyle 1 is joined to the upper end of the tibial pad 2; the lower end of the tibial pad 2 is joined to the tibial tray platform 4; 1 and tibial tray 3 are made of polyetheretherketone or its derivative material, tibial liner 2 is made of ultra-high molecular weight polyethylene; tibial liner 2 is double sliding tibial liner 2, in which femoral condyle 1 is paired with tibial liner 2 The sliding surface of the tibial pad 2 and the sliding surface of the tibial tray 3 are smooth sliding surfaces.

In addition, in this utility model, through the matching of material properties between the polyethylene tibial liner 2 and the PEEK tibial support 3, the PEEK femoral condyle 1 pair polyethylene tibial liner 2 and the PEEK tibial support 3 pair polyethylene tibial liner 2 The cushioning of the two sliding surfaces controls the displacement between the two; since the addition of the PEEK tibial support 3 can effectively transmit the motion load, the sliding between the PEEK femoral condyle 1 and the polyethylene tibial liner 2 and the PEEK tibial The sliding movement between the holder 3 and the polyethylene tibial liner 2 is matched to reduce the alternating shear caused by multi-directional movement, thereby greatly reducing the overall wear of the two surfaces of the polyethylene liner 2 .

According to the ISO14243 standard test, the wear amount is reduced to 4.3±1.1mm ³ /million, which is much better than the wear amount of the currently used CoCrMo on polyethylene (9.0±4.0mm ³ /million), so it can be predicted that the knee joint based on wear The life span can reach more than 40 years from the current 20 years. This fully provides the possibility of clinical application of the total knee joint system based on PEEK material.

In the above technical solution, as shown in Figure 4-6, the left and right sides of the femoral condyle 1 are provided with clamping grooves; the clamping grooves include metal or ceramic reinforcements 11 and 12 that match their shapes; One or more metal belt parts 33; the junction of the outer end of the stabilizing wing positioning part and the tibial support platform 4 contains a metal reinforcement; the metal reinforcement, the metal belt parts 33 and the metal reinforcement are all made of biocompatible metal or Its alloy composition; metal or its alloys include cobalt chromium molybdenum alloy, titanium or titanium alloy, tantalum or tantalum alloy, stainless steel and zirconium niobium alloy.

In the above technical solution, the joint surface between the upper surface of the polyetheretherketone (PEEK) tibial tray 3 and the lower surface of the ultrahigh molecular weight polyethylene (UHMWPE) double sliding tibial liner 2 adopts a rotatable or slidable design. In one embodiment, as shown in Figure 2 again, the upper surface of the polyether ether ketone (PEEK) tibial tray platform 4 is a smooth sliding surface, with a surface finish of Ra≤1.0 μm, preferably Ra<0.1 μm; The stabilizing wing positioning part 5 of 3 is provided with a hollow fixing column 31 perpendicular to the tibial support platform 4, and the opening of the hollow fixing column 31 is arranged on the upper surface of the tibial support platform 4; ultra-high molecular weight polyethylene (UHMWPE) double The lower part of the sliding tibial liner 2 is provided with a cylindrical or conical rotating column 21, which can be inserted into the hollow fixing column 31 through an opening on the upper surface, and its shape and size are the same as those of the lower end of the PEEK tibial tray 3 fixing column 31. The hollow part matches.

In another embodiment, as shown in FIG. 3 again, the upper surface of the polyether ether ketone (PEEK) tibial tray 3 is a smooth sliding surface, and its surface finish is Ra≤1.0 μm, preferably Ra<0.1 μm; 3 The upper end is provided with a raised rotating post 32; the lower part of the ultra-high molecular weight polyethylene (UHMWPE) double sliding tibial liner 2 is provided with a concave cavity (not shown), its shape and size are the same as the PEEK tibial tray 3 protruding The swivel column 32 matches.

The above descriptions are only preferred embodiments of the present utility model, and are not used to limit the implementation scope of the present utility model; if the utility model is modified or equivalently replaced without departing from the spirit and scope of the present utility model, all should be covered by this utility model. within the protection scope of utility model claims.

Claims (10)

1. the two slip artificial knee joint of high-molecular organic material, is characterized in that, comprise condyle of femur, tibia liner and tibia support, wherein:

Described tibia support comprises tibia support platform and stabilizer location division, and described stabilizer location division to be arranged on below described tibia support platform and vertical with described tibia support platform; The lower end of described condyle of femur engages with the upper end of described tibia liner; The lower end of described tibia liner engages with described tibia support platform; Described condyle of femur, described tibia liner and described tibia support are formed by macromolecular material, and wherein said condyle of femur and described tibia support are made up of polyether-ether-ketone or derivatives thereof, and described tibia liner is made up of ultra-high molecular weight polyethylene; Described tibia liner is two slip tibia liners, and to the sliding surface of described tibia liner and described tibia support, the sliding surface to described tibia liner is smooth sliding surface to wherein said condyle of femur.

2. the two slip artificial knee joint of high-molecular organic material according to claim 1, it is characterized in that, the surface smoothness of described sliding surface is not more than 1.0 μm.

3. the two slip artificial knee joint of high-molecular organic material according to claim 2, it is characterized in that, the surface smoothness of described sliding surface is less than 0.1 μm.

4. the two slip artificial knee joint of high-molecular organic material according to claim 1, it is characterized in that, the left and right sides of described condyle of femur is provided with clip slot; Described clip slot comprises and the metal of its form fit or ceramic stiffener; Described tibia support platform upper end sidewall comprises one or more metal band-shaped parts.

5. the two slip artificial knee joint of high-molecular organic material according to claim 1, it is characterized in that, the intersection of described outer end, stabilizer location division and described tibia support platform comprises metal rib.

6. the two slip artificial knee joint of high-molecular organic material according to claim 4, is characterized in that, described metal reinforcement, described metal band-shaped parts are formed by biocompatibility metal or its alloy; Described metal or its alloy comprise vitallium, titanium or titanium alloy, tantalum or tantalum alloy, rustless steel and zirconium-niobium alloy.

7. the two slip artificial knee joint of high-molecular organic material according to claim 5, it is characterized in that, described metal rib is made up of biocompatibility metal or its alloy; Described metal or its alloy comprise vitallium, titanium or titanium alloy, tantalum or tantalum alloy, rustless steel and zirconium-niobium alloy.

8. the two slip artificial knee joint of high-molecular organic material according to claim 1, it is characterized in that, be provided with the hollow fixed leg vertical with described tibia support platform in described stabilizer location division, and the opening of described hollow fixed leg is arranged on the upper surface of described tibia support platform; Or the upper surface of described platform is provided with protruding column spinner;

Described pair of slip tibia liner lower is provided with cylindric or pyramidal column spinner; Or the described pair of slip tibia liner lower is set to the cavity concaved.

9. the two slip artificial knee joint of high-molecular organic material according to claim 8, it is characterized in that, described hollow fixed leg and described cylindric or pyramidal column spinner match; Column spinner and the described cavity concaved of described projection match.

10. the two slip artificial knee joint of the high-molecular organic material according to any one in claim 1-9, it is characterized in that, described condyle of femur, described pair of slip tibia liner and described tibia support can combine flexibly and dismantle.