Tibia component locking structure

Abstract

The utility model provides a tibia component locking structure which comprises a tibia liner and a tibia support, the upper surface of the tibia support is provided with a front limiting boss and a rear limiting boss located behind the front limiting boss, and an inclined guide face and a front bayonet located below the inclined guide face are formed on the outer edge of the rear side of the front limiting boss; the tibia liner is provided with a front positioning groove and a rear positioning groove, a front buckle is arranged in the front positioning groove, and an arc-shaped guide surface is arranged at the tail end of the front buckle; rear buckles are arranged on the groove walls of the two sides of the rear positioning groove; the front limiting boss is in interference fit with the interior of the front positioning groove of the tibia liner and is clamped in the front bayonet through the front buckle to realize fixation; the rear limiting boss is in interference fit with the interior of the rear positioning groove of the tibia liner and is clamped in the rear bayonet through the rear buckle to realize fixation; and rapid implantation and stability improvement are facilitated.

Description

Technical Field

[0001] This utility model relates to the field of medical devices, specifically to a tibial component locking structure. Background Technology

[0002] The knee joint is one of the largest and most complex joints in the human body, and it is the most important joint for human movement. Knee joint prosthesis systems have been developed for decades. When the natural knee joint loses some or all of its function due to disease or injury, a knee joint prosthesis system is needed to replace it, restoring normal knee joint function, reducing patient pain and inconvenience. Knee joint prosthesis replacement surgery can achieve the best treatment results and restore the patient's mobility to the greatest extent possible.

[0003] A knee prosthesis consists of the femoral condyle, tibial liner, tibial support, and patellar prosthesis. The tibial liner and tibial support together form the tibial assembly. The tibial assembly is the most important part of knee replacement surgery, and the connection strength and safe and effective implantation of the locking structure between the tibial liner and tibial support are crucial to the success of the surgery. In clinical practice, an improperly designed locking structure can easily lead to tibial liner locking failure during implantation, requiring replacement of the prosthesis, resulting in prolonged surgery time or premature wear. Therefore, the locking structure between the tibial support and tibial liner is critical to the success of knee surgery. Utility Model Content

[0004] To address the aforementioned problems, this invention provides a tibial component locking structure.

[0005] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0006] A tibial component locking structure includes a tibial pad and a tibial support. The upper surface of the tibial support is provided with a front limiting boss and a rear limiting boss located behind the front limiting boss. The rear outer edge of the front limiting boss forms an inclined guide surface and a front locking slot located below the inclined guide surface. The rear limiting boss includes a longitudinal boss section, a trapezoidal boss section connecting the rear end of the longitudinal boss section and gradually increasing in width, and two oblique boss sections connecting the two sides of the rear end of the trapezoidal boss section. The sidewalls of the two oblique boss sections are provided with rear locking slots.

[0007] The tibial liner has a front positioning groove and a rear positioning groove. A front buckle is provided in the front positioning groove, and the end of the front buckle has an arc-shaped guide surface. Rear buckles are provided on both sides of the rear positioning groove.

[0008] The front limiting boss is interference-fitted into the front positioning groove of the tibial liner and is fixed by being snapped into the front locking opening by the front buckle; the rear limiting boss is interference-fitted into the rear positioning groove of the tibial liner and is fixed by being snapped into the rear locking opening by the rear buckle.

[0009] Furthermore, the front buckle is an elastic buckle with elastic deformation.

[0010] Furthermore, the front buckle includes an elastic arm protruding from the bottom of the front positioning groove and a hook portion connecting the end of the elastic arm and protruding forward, wherein the end of the hook portion is provided with the arc-shaped guide surface.

[0011] Furthermore, the hook portion has a straight section of equal width, and the arc-shaped guide surface intersects with the straight section.

[0012] Furthermore, the thickness of the elastic arm is 1.5±0.2mm, the thickness of the straight section of the hook portion is 2.5±0.2mm, the height of the straight section of the hook portion is 0.2mm, and the arc-shaped guide surface is an arc surface with a radius of 3±0.5mm.

[0013] Furthermore, the inner diameter of the front positioning groove is 0.15±0.1mm smaller than the outer diameter of the front limiting boss, thereby forming an interference fit.

[0014] Furthermore, the inner diameter of the rear positioning groove is 0.15±0.1mm smaller than the outer diameter of the rear limiting boss, thereby forming an interference fit.

[0015] Furthermore, the angle between the inclined guide surface and the normal line of the front limiting boss is 35°-55°; the height between the outermost edge of the inclined guide surface and the front bayonet is 0.65±0.3mm.

[0016] Furthermore, the outer edges of the front limiting boss and the rear limiting boss are chamfered.

[0017] Furthermore, the top of the groove walls of the front and rear positioning grooves are chamfered.

[0018] The technical solution provided by this utility model has the following beneficial effects:

[0019] The anterior limiting boss is interference-fitted into the anterior positioning groove of the tibial liner and secured by a front snap fastener within the anterior locking slot. Similarly, the posterior limiting boss is interference-fitted into the posterior positioning groove of the tibial liner and secured by a rear snap fastener within the posterior locking slot. This achieves a stable and secure connection between the tibial liner and the tibial support. Furthermore, the structural design of the posterior limiting boss, consisting of a longitudinal boss segment, a trapezoidal boss segment, and two oblique boss segments connected sequentially from front to back, provides automatic guidance when engaging with the posterior positioning groove, facilitating rapid implantation. Additionally, the inclined guide surface above the anterior locking slot and the arc-shaped guide surface at the end of the front snap fastener guide each other, allowing for smoother insertion of the tibial liner and tibial support. This effectively improves the success rate of knee surgery. Attached Figure Description

[0020] Figure 1 The diagram shown is a schematic representation of the tibial component locking structure in the embodiment.

[0021] Figure 2 As shown Figure 1 Sectional view of line AA in the middle;

[0022] Figure 3 As shown Figure 1 Sectional view of the middle BB line;

[0023] Figure 4 The figure shown is a three-dimensional structural diagram of the tibial support in the embodiment;

[0024] Figure 5 The image shown is a top view of the tibia support in the embodiment;

[0025] Figure 6 As shown Figure 5 A cross-sectional view of the CC line;

[0026] Figure 7 As shown Figure 6 Enlarged schematic diagram of region D in the middle;

[0027] Figure 8 The figure shown is a three-dimensional structural diagram of the tibial pad in the embodiment;

[0028] Figure 9 The image shown is a bottom view of the tibial liner in the embodiment;

[0029] Figure 10 The image shown is a cross-sectional view of the tibial liner in the embodiment;

[0030] Figure 11 The example shown is from an embodiment. Figure 10 A magnified view of region E in the middle. Detailed Implementation

[0031] To further illustrate each embodiment, the present utility model provides attached drawings. These drawings are a part of the disclosure of the present utility model, mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principle of the embodiments. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present utility model. The components in the drawings are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0032] In the description of the present invention, the orientation or positional relationships such as "upper", "lower", "left", "right", "front", "rear", etc. are based on the orientation or positional relationships shown in the attached drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0033] The present utility model will be further described below in conjunction with the attached drawings and specific implementation manners.

[0034] Refer to Figures 1 to 11 As shown, a locking structure for a tibial component provided in this embodiment includes a tibial liner 20 and a tibial tray 10. Among them, the upper surface of the tibial tray 10 is provided with a front limiting boss 11 and a rear limiting boss 12 located behind the front limiting boss 11. An inclined guiding surface 111 is formed on the rear outer edge of the front limiting boss 11 and a front bayonet 112 is located below the inclined guiding surface 111. The rear limiting boss 12 includes a longitudinal boss section 121, a trapezoidal boss section 122 connecting the rear end of the longitudinal boss section 121 and gradually increasing in width, and two oblique boss sections 123 connecting the two sides of the rear end of the trapezoidal boss section 122, thus forming a structure similar to a "human" shape; rear bayonets 124 are provided on the side walls of the two oblique boss sections 123. Specifically, in this embodiment, the longitudinal boss section 121 is a constant-width structure, and the two sides of its front end are designed with rounded corners.

[0035] The tibial liner 20 has a front positioning groove 21 and a rear positioning groove 22. A front buckle 23 is provided in the front positioning groove 21, and an arc-shaped guiding surface 233 is provided at the end of the front buckle 23; rear buckles 24 are provided on the two side walls of the rear positioning groove 22.

[0036] Specifically, in this embodiment, the front positioning groove 21 is adapted to the outer shape of the front limiting boss 11, and the rear positioning groove 22 is adapted to the outer shape of the rear limiting boss 12.

[0037] The front limiting boss 11 is press-fitted into the front positioning groove 21 of the tibial liner 20 and is fixed by being snapped into the front bayonet 112 through the front buckle 23; the rear limiting boss 12 is press-fitted into the rear positioning groove 22 of the tibial liner 20 and is fixed by being snapped into the rear bayonet 124 through the rear buckle 24.

[0038] During assembly, the tibial pad 20 is placed above the tibial support 10, with the front positioning groove 21 corresponding to the front limiting boss 11 and the rear positioning groove 22 corresponding to the rear limiting boss 12. External force is applied downwards. During this process, the "V"-shaped structure of the rear limiting boss 12, consisting of a longitudinal boss segment 121, a trapezoidal boss segment 122, and two oblique boss segments 123 connected sequentially from front to back, automatically guides the rear positioning groove 22, facilitating rapid implantation. Simultaneously, as the tibial pad 20 is continuously pressed downwards, the arc-shaped guide surface 233 at the end of the front latch 23 of the tibial pad 20 engages with the inclined guide surface 111 above the front latch 112, allowing the front latch 23 to more easily engage with the front latch 112. This achieves a stable and secure connection between the tibial pad 20 and the tibial support 10, effectively improving the success rate of knee surgery.

[0039] The front buckle 23 is an elastic buckle with elastic deformation. When inserted, it quickly snaps into the front bayonet 112 through a certain elastic deformation, and then achieves a firm engagement by restoring its deformation.

[0040] Specifically, the front buckle 23 includes an elastic arm 231 protruding from the bottom of the front positioning groove 21 and a hook portion 232 connecting the end of the elastic arm 231 and protruding forward. The end of the hook portion 232 is provided with the arc-shaped guide surface 233. The hook portion 232 has a straight section 234 of equal width, and the arc-shaped guide surface 233 intersects with the straight section 234; this gives the hook portion 232 a certain strength and makes it less prone to breakage.

[0041] Furthermore, in this specific embodiment, the thickness W1 of the elastic arm 231 is 1.5±0.2mm, and the thickness W2 of the straight section 234 of the hook portion 232 is 2.5±0.2mm. This configuration optimizes the performance of the front buckle 23, effectively enhancing its strength while satisfying deformation and recovery capabilities. Simultaneously, the height H2 of the straight section 234 of the hook portion 232 is 0.2mm, ensuring the strength of the hook portion 232. The arc-shaped guide surface 233 is an arc surface with a radius of 3±0.5mm. The intersection of this arc-shaped guide surface 233 and the straight section 234 of the hook portion 232 ensures a smooth transition to the snap-fit ​​engagement after the front buckle 23 is guided by the inclined guide surface 111. The above-described design of the structure and dimensions of the front buckle 23 represents a preferred solution. Of course, in other embodiments, the structure and size of the front buckle 23 are not limited to this. The various dimensions mentioned above can be adjusted within an appropriate range, as long as the front buckle 23 can be smoothly engaged.

[0042] More preferably, the angle between the inclined guide surface 111 and the normal line of the front limiting boss 11 is 35°-55°; the height dimension H1 between the outermost edge of the inclined guide surface 111 and the front bayonet 112 is 0.65±0.3mm. This setting ensures structural strength while guaranteeing that the inclined guide surface 111 provides guidance.

[0043] In this embodiment, the inner diameter of the front positioning groove 21 is 0.15±0.1mm smaller than the outer diameter of the front limiting boss 11, thus forming an interference fit; and the inner diameter of the rear positioning groove 22 is 0.15±0.1mm smaller than the outer diameter of the rear limiting boss 12, thus forming an interference fit. The interference fit is designed to be 0.15±0.1mm, ensuring a stable fit without affecting assembly due to excessive dimensional differences; this is a preferred parameter. Of course, in other embodiments, the specific dimensions of the interference fit can be adjusted according to actual conditions.

[0044] The outer edges of the front limiting boss 11 and the rear limiting boss 12 are chamfered, as are the tops of the groove walls of the front positioning groove 21 and the rear positioning groove 22. The chamfered edges eliminate sharp edges and provide good guidance, facilitating assembly.

[0045] The tibial component locking structure provided in this embodiment can improve the connection strength by about 45% compared to the existing mating structure.

[0046] Although the present invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the present invention without departing from the spirit and scope of the present invention as defined in the appended claims, and all such changes shall be within the scope of protection of the present invention.

Claims

1. A tibial component locking structure, comprising a tibial pad and a tibial support, characterized in that: The upper surface of the tibial support is provided with a front limiting protrusion and a rear limiting protrusion located behind the front limiting protrusion. The rear outer edge of the front limiting protrusion forms an inclined guide surface and a front locking slot located below the inclined guide surface. The rear limiting protrusion includes a longitudinal protrusion section, a trapezoidal protrusion section that connects to the rear end of the longitudinal protrusion section and gradually increases in width, and two oblique protrusion sections that connect the two sides of the rear end of the trapezoidal protrusion section. The side walls of the two oblique protrusion sections are provided with rear locking slots. The tibial liner has a front positioning groove and a rear positioning groove. A front buckle is provided in the front positioning groove, and the end of the front buckle has an arc-shaped guide surface. Rear buckles are provided on both sides of the rear positioning groove. The front limiting boss is interference-fitted into the front positioning groove of the tibial liner and is fixed by being snapped into the front locking opening by the front buckle; the rear limiting boss is interference-fitted into the rear positioning groove of the tibial liner and is fixed by being snapped into the rear locking opening by the rear buckle.

2. The tibial component locking structure according to claim 1, characterized in that: The front buckle is an elastic buckle with elastic deformation.

3. The tibial component locking structure according to claim 2, characterized in that: The front buckle includes an elastic arm protruding from the bottom of the front positioning groove and a hook portion that connects to the end of the elastic arm and protrudes forward. The end of the hook portion is provided with the arc-shaped guide surface.

4. The tibial component locking structure according to claim 3, characterized in that: The hook portion has a straight section of equal width, and the arc-shaped guide surface intersects with the straight section.

5. The tibial component locking structure according to claim 4, characterized in that: The elastic arm has a thickness of 1.5±0.2mm, the straight section of the hook has a thickness of 2.5±0.2mm, the straight section of the hook has a height of 0.2mm, and the arc-shaped guide surface is an arc surface with a radius of 3±0.5mm.

6. The tibial component locking structure according to claim 1, characterized in that: The inner diameter of the front positioning groove is 0.15±0.1mm smaller than the outer diameter of the front limiting boss, thus forming an interference fit.

7. The tibial component locking structure according to claim 1 or 6, characterized in that: The inner diameter of the rear positioning groove is 0.15±0.1mm smaller than the outer diameter of the rear limiting boss, thus forming an interference fit.

8. The tibial component locking structure according to claim 1, characterized in that: The angle between the inclined guide surface and the normal line of the front limiting boss is 45°±10°; the height between the outermost edge of the inclined guide surface and the front bayonet is 0.65±0.3mm.

9. The tibial component locking structure according to claim 1, characterized in that: The outer edges of the front and rear limiting bosses are chamfered.

10. The tibial component locking structure according to claim 1 or 9, characterized in that: The top of the groove walls of the front and rear positioning grooves are chamfered.

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