A bone stem positioning structure of an artificial joint

Abstract

The utility model discloses a bone handle positioning structure of artificial joint, including joint axle seat, bone handle and set between the both positioning structure body, the top of joint axle seat is provided with thread groove, is provided with gasket groove on the bottom inner wall of thread groove, is provided with axle groove on the bottom inner wall of gasket groove, and the bottom end of bone handle is movably inserted into the axle groove. The utility model discloses a series of structure is set up, is convenient for to bone handle pressure fixed position restriction and integrated automatic to threaded part elasticity tight anti -looseness, utilizes the tight elasticity that always exists, improves the thread engagement locking strength of threaded part, reduces the risk of positioning failure caused by thread loosening when long -term application, improves the stability of use, and through the mode of the movable sleeve of conical sleeve screwing cooperation, when the bone handle or conical sleeve is split and is replaced individually after long -term use and the like factors such as serious wear, reduce the cost phenomenon caused by overall replacement, improve the use flexibility.

Description

Technical Field

[0001] This utility model relates to the field of bone stem positioning technology, specifically to a bone stem positioning structure for an artificial joint. Background Technology

[0002] Common sites for artificial joint replacement surgery are the hip or knee joints, which are located on both sides of the pelvis and support most of the body's weight. Therefore, if the artificial bone is not placed ideally or not accurately aligned, it can cause the connection to loosen, resulting in the joint and the bone stem not being securely connected. Furthermore, the growth and curvature angle of the bones of each patient undergoing artificial joint replacement surgery are different. Therefore, for a precise artificial joint, the connection angle between the artificial joint and the bone stem needs to be precisely positioned to prevent the artificial joint from loosening due to improper lateral forces.

[0003] According to the novelty search report, CN2873139Y discloses a bone stem positioning structure for an artificial joint. This structure mainly involves forming a bearing seat with a tapered shaft hole on the artificial joint. The outer end of the shaft hole has a polygonal directional groove and a threaded section. The joint end of the bone stem and the artificial joint has a tapered connecting post that matches the shaft hole, allowing the bone stem to be locked and positioned on the bearing seat using a locking sleeve with a tapered perforation. Thus, when the connecting post of the bone stem is inserted and locked to the bearing seat of the artificial joint, the matching tapered angle between the connecting post and the shaft hole, combined with the reverse downward pressure from the inner tapered hole of the locking sleeve, allows the bone stem to obtain the optimal tight positioning angle.

[0004] The aforementioned technology discloses a bone stem positioning structure for an artificial joint. This structure uses a tapered pressure-guiding section on the bone stem, and a locking sleeve, screwed in through a thread, to compress and restrict the outer side of the tapered pressure-guiding section, thus preventing the bone stem from slipping out. However, this method still has the following shortcomings: the locking sleeve's compression method, relying solely on threaded insertion, results in insufficient damping and locking force, and long-term use carries a risk of significant thread loosening leading to positioning failure. Therefore, improvements are needed. This application proposes a bone stem positioning structure for an artificial joint to address these problems. Utility Model Content

[0005] The purpose of this invention is to provide a bone stem positioning structure for an artificial joint to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a bone stem positioning structure for an artificial joint, comprising a joint bearing, a bone stem, and a positioning structure body disposed between the two, wherein a threaded groove is provided on the top of the joint bearing, a gasket groove is provided on the bottom inner wall of the threaded groove, a shaft groove is provided on the bottom inner wall of the gasket groove, and the bottom end of the bone stem is movably inserted into the shaft groove.

[0007] The positioning structure body includes:

[0008] A conical sleeve is installed on the outside of the bone stem and makes movable contact with the bottom inner wall of the pad groove;

[0009] The external threaded sleeve has its threads screwed into the threaded groove and is movably pressed against the outside of the tapered sleeve.

[0010] The elastic damping and wear-increasing assembly is installed in a ring at equal intervals at the bottom of the external threaded sleeve. The elastic damping and wear-increasing assembly is used to elastically tighten the external threaded sleeve after it is screwed in and pressed, so as to increase the thread engagement damping and anti-loosening force between it and the thread groove.

[0011] Multiple annular gaskets are stacked and movable within a gasket groove, and make active contact with the elastic damping wear-increasing component. The annular gaskets are configured to be used to rotate and change the thickness of the appropriate number of gaskets to change the tension of the elastic damping wear-increasing component.

[0012] Preferably, the conical sleeve is fixedly connected to the outside of the bone stem by adhesive.

[0013] Preferably, the conical sleeve is detachably mounted on the outside of the bone handle.

[0014] Preferably, the conical sleeve has circular grooves on both the front and rear sides, and bolt holes are formed on the inner wall of the circular grooves on the side away from their openings. The bone handle has threaded grooves on both the front and rear sides, and hexagonal bolts are threaded into the threaded grooves. The hexagonal bolts consist of hexagonal heads and stainless steel studs. The circular grooves are movably fitted on the outside of the corresponding hexagonal heads, and the bolt holes are movably fitted on the outside of the corresponding stainless steel studs.

[0015] Preferably, the elastic damping wear-increasing assembly includes a vertical guide rod. The bottom of the external threaded sleeve has four vertical guide grooves that are evenly spaced in an annular shape. The vertical guide rod is slidably sleeved in the corresponding vertical guide groove. A compression spring in a compressed state is fixedly connected between the top inner wall of the vertical guide groove and the top end of the corresponding vertical guide rod. A support block is fixedly connected to the bottom end of the vertical guide rod. A ball is movably embedded in the bottom of the support block. The ball is pressed tightly against the top of the uppermost annular washer.

[0016] Preferably, both sides of the external threaded sleeve are provided with horizontal portions for engaging the wrench.

[0017] Preferably, a retaining ring is fixedly connected to the upper inner side of the external threaded sleeve, and the retaining ring is movably sleeved on the outside of the bone handle and located above the conical sleeve.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] 1. By cooperating with the set bone handle, conical sleeve, shaft groove, annular gasket, threaded groove, external threaded sleeve and elastic damping grinding component, the external threaded sleeve can be rotated and moved down to press and restrict the conical sleeve, thereby achieving the fixed position limit of the bone handle. When the bone handle is pressed and fixed, the threaded parts can be automatically and elastically tightened to prevent loosening. By utilizing the always-present tensioning elastic force, the thread engagement locking force of the threaded parts is improved, reducing the risk of positioning failure due to thread loosening during long-term use and improving the stability of use.

[0020] 2. In addition, the number of annular shims can be adjusted by personnel to flexibly control the number. The support height of the ball bearing can be changed by increasing or changing the number of annular shims, thereby changing the tension of the compression spring during compression and changing its elastic force. This allows for subsequent disassembly and maintenance after long-term use, further improving the flexibility of use.

[0021] 3. The tapered sleeve is secured by an internal hex bolt, and the tapered sleeve is movably fitted onto the outside of the bone handle. After long-term use, when severe wear occurs, the bone handle or tapered sleeve can be disassembled and replaced separately, reducing the high cost of replacing the whole unit and improving the flexibility of use.

[0022] This invention incorporates a series of structures that facilitate the fixed positioning of the bone stem and automatically and elastically tighten the threaded parts to prevent loosening. The constant tension enhances the thread engagement and locking force, reducing the risk of positioning failure due to thread loosening during long-term use and improving operational stability. Furthermore, the movable fitting of the conical sleeve allows for individual replacement of the bone stem or conical sleeve after prolonged use, reducing the high cost of overall replacement and increasing operational flexibility. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the bone stem positioning structure of an artificial joint according to Embodiment 1 of this utility model;

[0024] Figure 2 This is a schematic diagram of the main sectional view of the bone stem positioning structure of an artificial joint according to Embodiment 1 of this utility model.

[0025] Figure 3 for Figure 2 A magnified structural diagram of part A in the diagram;

[0026] Figure 4 This is a front sectional view of the bone stem positioning structure of an artificial joint according to Embodiment 2 of this utility model.

[0027] In the diagram: 1. Joint bearing; 11. Shaft groove; 12. Shim groove; 13. Threaded groove; 2. Bone handle; 21. Conical sleeve; 22. Round groove; 23. Socket head bolt; 3. External threaded sleeve; 31. Horizontal part; 32. Retaining ring; 4. Vertical guide groove; 41. Vertical guide rod; 42. Compression spring; 43. Support block; 44. Ball bearing; 5. Annular washer. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Example 1

[0030] like Figures 1 to 3 As shown, the artificial joint stem positioning structure proposed in this embodiment includes a joint bearing 1, a stem 2 and a positioning structure body disposed between the two. The joint bearing 1 has a threaded groove 13 on its top, a gasket groove 12 on the bottom inner wall of the threaded groove 13, and a shaft groove 11 on the bottom inner wall of the gasket groove 12. The bottom end of the stem 2 is movably inserted into the shaft groove 11.

[0031] The positioning structure body includes:

[0032] The conical sleeve 21 is installed on the outside of the bone handle 2 and makes movable contact with the bottom inner wall of the pad groove 12;

[0033] The external threaded sleeve 3 is threaded into the threaded groove 13 and is movably pressed against the outside of the conical sleeve 21. Both sides of the external threaded sleeve 3 are provided with horizontal parts 31 for engaging the wrench. A retaining ring 32 is fixedly connected to the upper part of the inner side of the external threaded sleeve 3. The retaining ring 32 is movably sleeved on the outside of the bone handle 2 and located above the conical sleeve 21.

[0034] The elastic damping and wear-increasing assembly is installed in a ring at equal intervals at the bottom of the external threaded sleeve 3. The elastic damping and wear-increasing assembly is used to elastically tighten the external threaded sleeve 3 after it is screwed in and pressed, so as to increase the thread engagement damping and anti-loosening force between it and the thread groove 13.

[0035] Annular gaskets 5, which are multiple and movably stacked in the gasket groove 12, are in active contact with the elastic damping wear-increasing assembly; the annular gaskets 5 are configured to rotate to change the thickness of the appropriate number to change the tension of the elastic damping wear-increasing assembly.

[0036] Specifically, the conical sleeve 21 is fixedly connected to the outside of the bone stem 2 by glue.

[0037] Furthermore, the elastic damping wear-increasing assembly includes a vertical guide rod 41. The bottom of the external threaded sleeve 3 has four equally spaced vertical guide grooves 4 arranged in an annular pattern. The vertical guide rod 41 is slidably fitted into the corresponding vertical guide groove 4. A compression spring 42 in a compressed state is fixedly connected between the top inner wall of the vertical guide groove 4 and the top of the corresponding vertical guide rod 41. A support block 43 is fixedly connected to the bottom of the vertical guide rod 41. A ball bearing 44 is movably embedded in the bottom of the support block 43, and the ball bearing 44 is in tight contact with the top of the uppermost annular washer 5. The vertical guide grooves 4, vertical guide rod 41, compression spring 42, support block 43, and ball bearing 44 work together so that when the external threaded sleeve 3 is screwed downwards, the external threaded sleeve 3 sequentially drives the four ball bearings 44 to rotate and move downwards through the four vertical guide rods 41 and the four support blocks 43. When the ball bearing 44 moves downwards and contacts the uppermost annular washer 5, it is blocked and restricted by it. As the sleeve moves downward, the external threaded sleeve 3 continues to slide down on the four vertical guide rods 41, compressing the four compression springs 42 until the external threaded sleeve 3 is pressed tightly against the outside of the tapered sleeve 21. The four compression springs 42, in their compressed state, maintain a constant tension force on the external threaded sleeve 3. This tension force ensures a tight meshing between the external threaded sleeve 3 and the threaded groove 13, increasing the meshing damping and anti-loosening force of the threads, reducing the risk of loosening during prolonged use, and improving operational stability. Additionally, the height of the ball bearing 44 can be adjusted by increasing or changing the number of annular washers 5, thereby altering the tension of the compression springs 42 during pressing and changing their elastic force. This facilitates subsequent maintenance and adjustments after long-term use, further improving operational flexibility.

[0038] The usage method of this embodiment is as follows: When using the bone stem positioning structure of this artificial joint, firstly, the bottom end of the bone stem 2 passes through the annular washer 5 and is inserted into the shaft groove 11. The bone stem 2 drives the conical sleeve 21 to press against the bottom inner wall of the washer groove 12. Then, the external threaded sleeve 3 is screwed downward into the threaded groove 13. The external threaded sleeve 3 drives the four balls 44 to rotate and move downward through the four vertical guide rods 41 and the four support blocks 43 in sequence. When the balls 44 move down to contact the uppermost annular washer 5, they are blocked and no longer move downward. At this time, the external threaded sleeve 3 continues to move downward and slides down on the four vertical guide rods 41, compressing the four compression springs 42 until the external threaded sleeve 3 is pressed tightly against the outside of the conical sleeve 21 and fixed. The elasticity of the four compression springs 42 in the compressed state is used to externally screw the ball 44 into the groove 13. The threaded sleeve 3 always has a tension spring force. Under the tension spring force, the threads of the external threaded sleeve 3 and the threaded groove 13 are tightly engaged, increasing the engagement damping and anti-loosening force of the threads of the two, reducing the risk of the external threaded sleeve 3 loosening during long-term use, and achieving the effect of positioning and limiting the bone handle 2 and automatically and elastically tightening and preventing loosening of the threaded parts. This improves the engagement locking force of the threaded parts, reduces the risk of positioning failure due to thread loosening during long-term use, and improves the stability of use. In addition, the support and limiting height of the ball 44 can be changed by increasing or changing the number of annular shims 5, thereby changing the tension of the compression spring 42 during compression and changing its elastic force. This allows for subsequent disassembly and maintenance adjustment after long-term use, further improving the flexibility of use.

[0039] Example 2

[0040] like Figure 4 As shown, this embodiment differs from Embodiment 1 in that: the conical sleeve 21 is detachably installed on the outside of the bone handle 2. Both the front and rear sides of the conical sleeve 21 have circular grooves 22. A bolt hole is formed on the inner wall of the circular groove 22 on the side away from its opening. Both the front and rear sides of the bone handle 2 have threaded grooves. An internal hexagonal bolt 23 is threaded into the threaded groove. The internal hexagonal bolt 23 consists of an internal hexagonal head and a stainless steel stud. The circular groove 22 is movably fitted onto the outside of the corresponding internal hexagonal head, and the bolt hole is movably fitted onto the outside of the corresponding stainless steel stud. The internal hexagonal bolt 23 is threadedly locked to the conical sleeve 21. Combined with the way the conical sleeve 21 is movably fitted onto the outside of the bone handle 2, after long-term use, the internal hexagonal bolt 23 can be loosened and removed, allowing the bone handle 2 to be pulled downwards from the conical sleeve 21. This facilitates individual replacement of the bone handle 2 or the conical sleeve 21 after long-term use due to severe wear, reducing the cost of overall replacement and improving usability.

[0041] The method of use in this embodiment is as follows: The difference from Embodiment 1 is that, based on Embodiment 1, it also has the following functions: In addition, the conical sleeve 21 is threaded and locked with the internal hex bolt 23. With the conical sleeve 21 movably placed on the outside of the bone handle 2, after long-term use, the bone handle 2 can be pulled out downward from the conical sleeve 21 by loosening and removing the internal hex bolt 23. This allows the bone handle 2 or the conical sleeve 21 to be replaced separately in case of severe wear or other factors after long-term use, reducing the high cost of overall replacement and improving the flexibility of use.

[0042] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A bone stem positioning structure of an artificial joint, comprising a joint shaft seat (1), a bone stem (2) and a positioning structure body arranged between the two, characterized in that: The joint bearing (1) has a threaded groove (13) at the top, a gasket groove (12) on the bottom inner wall of the threaded groove (13), a shaft groove (11) on the bottom inner wall of the gasket groove (12), and the bottom end of the bone stem (2) is movably inserted into the shaft groove (11). The positioning structure body includes: A conical sleeve (21) is installed on the outside of the bone stem (2) and makes movable contact with the bottom inner wall of the pad groove (12); The external threaded sleeve (3) is threaded into the threaded groove (13) and is movably pressed against the outside of the tapered sleeve (21); The elastic damping wear-increasing component is installed in a ring at equal intervals at the bottom of the external threaded sleeve (3); An annular gasket (5), which is multiple and dynamically stacked in the gasket groove (12), and dynamically contacts the elastic damping wear-increasing component.

2. The positioning structure for the stem of an artificial joint according to claim 1, characterized in that: The conical sleeve (21) is fixedly connected to the outside of the bone handle (2) by glue.

3. The positioning structure for the stem of an artificial joint according to claim 1, characterized in that: The conical sleeve (21) is detachably mounted on the outside of the bone handle (2).

4. The bone stem positioning structure for an artificial joint according to claim 3, characterized in that: The conical sleeve (21) has a circular groove (22) on both the front and rear sides. A bolt hole is provided on the inner wall of the circular groove (22) away from its opening. The bone handle (2) has a threaded groove on both the front and rear sides. An internal hexagon bolt (23) is threaded in the threaded groove. The internal hexagon bolt (23) consists of an internal hexagon head and a stainless steel stud. The circular groove (22) is movably fitted on the outside of the corresponding internal hexagon head, and the bolt hole is movably fitted on the outside of the corresponding stainless steel stud.

5. The bone stem positioning structure for an artificial joint according to claim 1, characterized in that: The elastic damping wear-increasing assembly includes a vertical guide rod (41). The bottom of the external threaded sleeve (3) is provided with four vertical guide grooves (4) at equal intervals in an annular shape. The vertical guide rod (41) is slidably sleeved in the corresponding vertical guide groove (4). A compression spring (42) in a compressed state is fixedly connected between the top inner wall of the vertical guide groove (4) and the top end of the corresponding vertical guide rod (41). A support block (43) is fixedly connected to the bottom end of the vertical guide rod (41). A ball bearing (44) is movably embedded in the bottom of the support block (43). The ball bearing (44) is pressed tightly against the top of the uppermost annular gasket (5).

6. The bone stem positioning structure for an artificial joint according to claim 1, characterized in that: Both sides of the external threaded sleeve (3) are provided with horizontal portions (31) for engaging the wrench.

7. The bone stem positioning structure for an artificial joint according to claim 1, characterized in that: A retaining ring (32) is fixedly connected to the upper inner side of the external threaded sleeve (3). The retaining ring (32) is movably sleeved on the outside of the bone handle (2) and located above the conical sleeve (21).

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