Assembled double-acting elastic capitulum radius prosthesis

Abstract

The utility model discloses an assembled double-acting elastic radius capitulum prosthesis, and relates to the technical field of orthopedic implantation. Comprising a double-acting radius head, a cobalt-chromium-molybdenum ball head and a titanium alloy medullary cavity handle, the cobalt-chromium-molybdenum ball head is located between the double-acting radius head and the titanium alloy medullary cavity handle, the cobalt-chromium-molybdenum ball head comprises a ball head block and a connecting column, one end of the ball head block of the cobalt-chromium-molybdenum ball head is connected with a ball joint of the double-acting radius head, and the other end of the ball head block of the cobalt-chromium-molybdenum ball head is connected with a ball joint of the titanium alloy medullary cavity handle. One end of a connecting column of the cobalt-chromium-molybdenum ball head is connected with the titanium alloy medullary cavity handle in an inserted mode, the double-acting radius head comprises a body and a ball groove, the ball head block slides on the inner wall of the ball groove, and a groove for increasing the moving range of the cobalt-chromium-molybdenum ball head is formed in the joint of the ball groove and the side face, facing the cobalt-chromium-molybdenum ball head, of the body. Through the arrangement of the double-acting radial head, the cobalt-chromium-molybdenum ball head, the titanium alloy medullary cavity handle and the like, the radial head capitulum prosthesis provides good mobility through the spherical structure contact surface, is good in flexibility and reduces the pressure of the capitulum humerus.

Description

Technical Field

[0001] The utility model relates to the technical field of orthopedic implantation, in particular to a modular double-motion elastic radial head prosthesis. Background Art

[0002] With the continuous improvement of implant design and surgical techniques, the effect of radial head prosthesis replacement is getting better and better. During the radial head prosthesis replacement process, the radial head prosthesis stem is implanted into the radial medullary cavity and then replaced and fixed.

[0003] The existing technical solution is to fix the radial head through an integrated method. However, since the radial head is a single-motion design, it is very easy to cause excessive pressure on the humeral head or limited mobility, resulting in delayed injury to the humeral head and low elbow joint mobility.

[0004] In recent years, modular radial head prostheses have also appeared. Since the radial head is a single-motion design, it is very easy to put excessive pressure on the humeral head or limit its range of motion, causing delayed injury to the humeral head and low elbow joint mobility. Utility Model Content

[0005] The utility model aims to provide a modular double-motion elastic radial head prosthesis to solve the problems of excessive pressure or limited range of motion during the replacement of the radial head prosthesis.

[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solution: a modular double-action elastic radial head prosthesis, comprising:

[0007] Dual-action radial head, cobalt-chromium-molybdenum ball head and titanium alloy intramedullary stem;

[0008] The cobalt-chromium-molybdenum ball head is located between the dual-motion radial head and the titanium alloy medullary stem;

[0009] The cobalt-chromium-molybdenum ball head comprises a ball head block and a connecting column, one end of the ball head block of the cobalt-chromium-molybdenum ball head is connected to the double-motion radial head ball joint, and one end of the connecting column of the cobalt-chromium-molybdenum ball head is plugged into the titanium alloy intramedullary stem.

[0010] Further to this solution, the dual-motion radial head includes a body and a ball groove;

[0011] The ball head block slides on the inner wall of the ball groove;

[0012] A groove for increasing the activity range of the cobalt-chromium-molybdenum ball head is provided at the intersection of the ball groove and a side surface of the body facing the cobalt-chromium-molybdenum ball head.

[0013] Further to this solution, the inner wall surface of the ball groove is paved with bumps, and the ball head block slides on the surface of the bumps to reduce friction.

[0014] Further to this plan,

[0015] The connecting column is provided with a slot 1;

[0016] An inner wall of the slot is inclined from one end close to the ball head block toward the axis of the connecting column;

[0017] The titanium alloy intramedullary stem comprises a first protrusion;

[0018] The protrusion is inserted into the slot to form a taper lock.

[0019] Further to this plan,

[0020] The titanium alloy intramedullary stem includes a second slot;

[0021] The second slot is inclined from the end away from the cobalt-chromium-molybdenum ball head toward the axis of the titanium alloy medullary cavity handle;

[0022] The cobalt-chromium-molybdenum ball head includes a second protrusion;

[0023] The second protrusion is plugged into the second slot to form a taper lock.

[0024] Further to this solution, the outer wall surface of the titanium alloy intramedullary stem is provided with a recessed groove for increasing the contact area with the intramedullary cavity, and the side of the dual-motion radial head away from the cobalt-chromium-molybdenum ball head is provided with a ball concave surface for reducing friction with the joint.

[0025] The ball groove passes through a side surface of the body and the diameter of the passing portion is less than or equal to the maximum diameter of the ball head block.

[0026] The ball head block and the connecting column are connected via a connecting piece, and the diameter of the connecting piece is smaller than the cross-sectional diameter of the ball head block and the connecting column.

[0027] Compared with the prior art, the beneficial effects of the utility model are:

[0028] The assembled dual-motion elastic radial capitellum prosthesis is provided with a dual-motion radial head, a cobalt-chromium-molybdenum ball head and a titanium alloy medullary stem. The radial capitellum prosthesis provides good mobility and flexibility through a spherical structure contact surface, thereby reducing the pressure on the humeral capitellum.

[0029] At the same time, the cobalt-chromium-molybdenum ball head and titanium alloy medullary stem can be combined with different medullary cavity lengths and spaces to adapt to different human body structures. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the cross-sectional structure of the radial head prosthesis of the utility model;

[0031] Figure 2 It is a schematic diagram of the connection and matching structure of the dual-action radial head, the cobalt-chromium-molybdenum ball head and the titanium alloy intramedullary stem of the utility model;

[0032] Figure 3This is a schematic structural diagram of one embodiment of the dual-action radial head of the utility model;

[0033] Figure 4 For the utility model Figure 1 The enlarged structural diagram of part A in the middle;

[0034] Figure 5 This is a schematic structural diagram of one embodiment of the cobalt-chromium-molybdenum ball head and titanium alloy intramedullary stem of the utility model;

[0035] Figure 6 It is a schematic diagram of the overall structure of the utility model.

[0036] In the figure: 1. dual-movable radial head; 101. body; 102. ball groove; 103. groove; 104. concave ball surface; 105. convex point; 2. cobalt-chromium-molybdenum ball head; 201. ball head block; 202. connecting column; 203. slot one; 204. protrusion two; 205. connecting plate; 3. titanium alloy intramedullary stem; 301. protrusion one; 302. slot two; 4. concave groove. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0038] Existing technology defects:

[0039] 1. The lack of elastic buffering in the metal radial head increases the tension after prosthesis replacement, causing elbow pain, and may not be suitable for various medullary cavity lengths and human body structures;

[0040] 2. The radial head is a single-motion prosthesis with low mobility, and replacement of the prosthesis causes decreased function of the elbow joint and forearm.

[0041] In order to better solve the problems of stress and limited range of motion after prosthesis replacement, a modular double-motion elastic radial head prosthesis has been invented.

[0042] like Figure 1 - Figure 2As shown, the embodiment of the utility model provides a modular dual-motion elastic radial head prosthesis, including a dual-motion radial head 1, a cobalt-chromium-molybdenum ball head 2 and a titanium alloy intramedullary handle 3, wherein the cobalt-chromium-molybdenum ball head 2 is located between the dual-motion radial head 1 and the titanium alloy intramedullary handle 3, wherein the cobalt-chromium-molybdenum ball head 2 includes a ball head block 201 and a connecting column 202, wherein one end of the ball head block 201 of the cobalt-chromium-molybdenum ball head 2 is connected to the ball joint of the dual-motion radial head 1, and one end of the connecting column 202 of the cobalt-chromium-molybdenum ball head 2 is plugged into the titanium alloy intramedullary handle 3, thereby, the The radial head capitellum prosthesis uses a cobalt-chromium-molybdenum ball head 2 as an intermediate piece to connect the dual-motion radial head 1 and the titanium alloy intramedullary stem 3. In this embodiment, the dual-motion radial head 1 is made of high-hinge or vitamin E polyethylene material, cobalt-chromium-molybdenum or zirconium-niobium alloy high-polishing material, and the dual-motion radial head 1 and the cobalt-chromium-molybdenum ball head 2 are provided with a spherical concave surface 104 spherical structure contact surface, which provides good mutual mobility. The cobalt-chromium-molybdenum ball head 2 and the titanium alloy intramedullary stem 3 can be combined with different intramedullary cavity lengths and bring adaptability to different human body structures.

[0043] The modular double-motion elastic radial head prosthesis provided by the embodiment of the utility model is described below in conjunction with the accompanying drawings.

[0044] Embodiment 1:

[0045] like Figure 2 As shown, in this embodiment, the dual-action radial head 1 includes a body 101 and a ball groove 102, and the ball head block 201 of the cobalt-chromium-molybdenum ball head 2 slides on the inner wall of the ball groove 102, providing the cobalt-chromium-molybdenum ball head 2 with sufficient range of motion and flexibility, avoiding the excessive pressure on the humeral head or limited mobility due to the single-action design of the radial head. In this embodiment, the ball groove 102 penetrates one side of the body 101, and a circle is formed at the penetration point on the side, and the R of the circle is less than the maximum diameter of the ball head block 201. The ball head block 201 can be directly placed in the ball groove 102, or when the dual-action radial head 1 is made of a high hinge or vitamin E polyethylene material, it has elasticity, and the ball head block 201 is pressed into the ball groove 102, and the ball groove 102 can limit the cobalt-chromium-molybdenum ball head 2 to prevent it from falling off;

[0046] like Figure 2 As shown, it can also be known that a groove 103 for increasing the range of movement of the cobalt-chromium-molybdenum ball head 2 is provided at the intersection of the ball groove 102 and the side of the body 101 facing the cobalt-chromium-molybdenum ball head 2. When the connecting column 202 of the cobalt-chromium-molybdenum ball head 2 is closer to one side of the body 101, the connecting column 202 has limited space for movement during rotation. The range of movement of the connecting column 202 can be increased by the groove 103. Note that the cross-sectional diameter of the connecting column 202 is smaller than the diameter of the groove 103.

[0047] The dual-action radial head 1 can also provide another embodiment, such as Figure 3For example, the inner wall surface of the ball groove 102 is paved with protrusions 105, which are evenly distributed on the inner wall of the ball groove 102 and contact the ball head block 201. The contact area between the ball head block 201 and the dual-movable radial head 1 is reduced and multiple points of contact are performed, thereby reducing the connection friction while ensuring the effect of stable contact.

[0048] Embodiment 2:

[0049] like Figure 4 As shown, this embodiment provides a connecting column 202 and a titanium alloy intramedullary stem 3, wherein a slot 203 is provided on the side of the connecting column 202 facing the titanium alloy intramedullary stem 3, the inner wall of the slot 203 is inclined from the end close to the ball head block 201 toward the axis of the connecting column 202, and the inner wall diameter of the slot 203 gradually increases from the end facing the connecting column 202 to the other end, and the titanium alloy intramedullary stem 3 includes a protrusion 301, which is inserted into the slot 203 to form a taper lock, and the diameters of each part of the protrusion 301 are consistent. The protrusion 301 is inserted into the slot 203, and the titanium alloy intramedullary stem 3 can move under the condition of the slot 203 to combine different intramedullary cavity lengths and bring to adapt to different human body structures.

[0050] like Figure 5 As shown, the connecting column 202 and the titanium alloy medullary cavity handle 3 also provide another embodiment, the titanium alloy medullary cavity handle 3 includes a second slot 302, the second slot 302 is inclined from the end away from the cobalt-chromium-molybdenum ball head 2 toward the axis of the titanium alloy medullary cavity handle 3, the cobalt-chromium-molybdenum ball head 2 includes a second protrusion 204, the second protrusion 204 is inserted into the second slot 302 to form a taper lock, similarly, the titanium alloy medullary cavity handle 3 can move under the condition of the second slot 302 to combine different medullary cavity lengths and between them to adapt to different human body structures.

[0051] Embodiment three:

[0052] like Figure 5 and Figure 6 As shown, in this embodiment, the outer wall surface of the titanium alloy intramedullary handle 3 is provided with a recessed groove 4 for increasing the contact area with the intramedullary cavity. In actual operation, the recessed groove 4 can assist the titanium alloy intramedullary handle 3 to be placed in the intramedullary cavity more stably, with better firmness and stability. The side of the dual-motion radial head 1 away from the cobalt-chromium-molybdenum ball head 2 is provided with a ball concave surface 104 for reducing friction with the joint, which fits the joint better and reduces discomfort after installation. The ball head block 201 and the connecting column 202 are connected by a connecting piece 205. The diameter of the connecting piece 205 is smaller than the cross-sectional diameter of the ball head block 201 and the connecting column 202. The connecting piece 205 is integrally formed with the ball head block 201 and the connecting column 202, thereby increasing the distance between the connecting column 202 and the body 101 and expanding the range of motion of the cobalt-chromium-molybdenum ball head 2.

[0053] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is limited by the attached embodiments and their equivalents.

Claims

1. A modular dual-motion elastic radial head prosthesis, characterized in that: include: Dual-action radial head (1), cobalt-chromium-molybdenum ball head (2) and titanium alloy intramedullary stem (3); The cobalt-chromium-molybdenum ball head (2) is located between the dual-motion radial head (1) and the titanium alloy intramedullary stem (3); The cobalt-chromium-molybdenum ball head (2) comprises a ball head block (201) and a connecting post (202); one end of the ball head block (201) of the cobalt-chromium-molybdenum ball head (2) is connected to the ball joint of the double-movable radial head (1); and one end of the connecting post (202) of the cobalt-chromium-molybdenum ball head (2) is plugged into the titanium alloy intramedullary stem (3).

2. The modular dual-motion elastic radial head prosthesis according to claim 1, characterized in that: The dual-action radial head (1) comprises a body (101) and a ball groove (102); The ball head block (201) slides on the inner wall of the ball groove (102); A groove (103) for increasing the range of motion of the cobalt-chromium-molybdenum ball head (2) is provided at the intersection of the ball groove (102) and a side surface of the body (101) facing the cobalt-chromium-molybdenum ball head (2).

3. The modular dual-motion elastic radial head prosthesis according to claim 2, characterized in that: The inner wall surface of the ball groove (102) is paved with convex points (105), and the ball head block (201) slides on the surface of the convex points (105) to reduce friction.

4. The modular dual-motion elastic radial head prosthesis according to claim 1, characterized in that: The connecting column (202) is provided with a slot 1 (203); The inner wall of the slot 1 (203) is inclined from one end close to the ball head block (201) toward the axis of the connecting column (202); The titanium alloy intramedullary handle (3) comprises a protrusion 1 (301); The protrusion 1 (301) is inserted into the slot 1 (203) to form a taper lock.

5. The modular dual-motion elastic radial head prosthesis according to claim 1, characterized in that: The titanium alloy intramedullary handle (3) comprises a second slot (302); The second slot (302) is inclined from the end away from the cobalt-chromium-molybdenum ball head (2) toward the axis of the titanium alloy medullary stem (3); The cobalt-chromium-molybdenum ball head (2) comprises a second protrusion (204); The second protrusion (204) is inserted into the second slot (302) to form a taper lock.

6. The modular dual-motion elastic radial head prosthesis according to claim 1, characterized in that: The outer wall surface of the titanium alloy intramedullary handle (3) is provided with a concave groove (4) for increasing the contact area with the intramedullary cavity, and the side of the dual-motion radial head (1) facing away from the cobalt-chromium-molybdenum ball head (2) is provided with a ball concave surface (104) for reducing friction with the joint.

7. The modular dual-motion elastic radial head prosthesis according to claim 3, characterized in that: The ball groove (102) penetrates through one side surface of the body (101), and the diameter of the penetration point is less than or equal to the maximum diameter of the ball head block (201).

8. The modular dual-motion elastic radial head prosthesis according to claim 1, characterized in that: The ball head block (201) and the connecting column (202) are connected via a connecting piece (205), and the diameter of the connecting piece (205) is smaller than the cross-sectional diameters of the ball head block (201) and the connecting column (202).

Images