Femoral head local replacement prosthesis assembly

Abstract

The invention discloses a femoral head local replacement prosthesis assembly which comprises a prosthesis column and a top cover which are finally implanted into a femoral head, and further comprises a mounting handle used when the prosthesis column is implanted. After the bone grafting channel is established, the prosthesis column and the installation handle are assembled, the prosthesis column is placed into the channel along the kirschner wire, when the prosthesis column is implanted, the head of the installation handle can be hammered to enable the prosthesis column to be embedded into the channel, the positioning nail at the bottom of the prosthesis column is smashed into the bone layer, and the prosthesis column and the bone substance can be fixed. Then the mounting handle is taken out, the top cover is fixedly assembled at the top of the prosthesis column, and the upper surface of the top cover is an arc surface matched with the camber of the femoral head and is matched with the defect surface of the femoral head, so that the top cover can be better fused with the femoral head.

Description

Technical Field

[0001] The invention relates to the field of femoral head prostheses, in particular to a femoral head partial replacement prosthesis component. Background Art

[0002] In recent years, the number of cases of avascular necrosis of the femoral head has been on the rise, and the patients are getting younger. The treatment methods for this type of complication have also become diversified, mainly divided into two categories: drug treatment and surgical treatment. The treatment effect varies from person to person. Commonly used ones include core decompression, free fibula transplantation, femoral head replacement and total hip replacement.

[0003] In stage I and II of avascular necrosis of the femoral head, core decompression or free fibula transplantation is generally used as the treatment method. The short-term effect is obvious, but the long-term follow-up effect is not ideal, and there is also the possibility of further necrosis and collapse of the femoral head.

[0004] Total hip replacement is suitable for patients with advanced femoral head necrosis, and the surgical effect is ideal. Although the success rate of total hip replacement is getting higher and higher, there are still many problems, especially for young patients with more activities. In addition to the prosthesis being more prone to aseptic loosening, there is a great possibility of late joint revision. Compared with the primary replacement, joint revision is difficult, lasts longer, has a large amount of bleeding, has a high risk of infection, and requires higher technical requirements for the surgeon. In addition, most of them are difficult to achieve the effect of the primary replacement, and are prone to catastrophic complications such as infection and dislocation. Revision with higher difficulty is required, which seriously affects the patient's quality of life. The high cost is a heavy burden for both the patient and the society. Therefore, although it has a definite therapeutic effect, total hip replacement should be postponed as much as possible in young and middle-aged patients.

[0005] Prostheses made of biocompatible materials or metal materials are now commonly used. By replacing the damaged and collapsed joint surface, they can effectively relieve patients' joint pain, restore hip joint function to the greatest extent, retain as much hip bone mass as possible, and delay or avoid total hip replacement. However, existing prostheses have defects such as poor fixation effect and inconvenient installation. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a firmly fixed femoral head partial replacement prosthesis component.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] A femoral head partial replacement prosthesis assembly, characterized by comprising:

[0009] A prosthetic column, the cross section of which is circular, the top of which has a convex or concave positioning portion located in the axial direction thereof, and the bottom of which has a plurality of protruding positioning pins;

[0010] A top cover, covering the top of the prosthesis column, wherein the upper surface of the top cover is an arc surface matching the curvature of the femoral head, and a fixing portion is provided at the bottom of the top cover, which is concavely and convexly engaged with the positioning portion and fixed thereto; and

[0011] The mounting handle comprises a limiting plate which can be in close contact with the top surface of the prosthesis column, a handle rod is fixed above the limiting plate, and a pressing part which matches the concave and convex part of the positioning part is fixed below the limiting plate.

[0012] A further technical solution is that after the prosthesis column and the mounting handle are assembled, a through hole is provided for the Kirschner wire to pass through, and the through hole on the mounting handle matches the diameter of the Kirschner wire to form a positioning hole.

[0013] A further technical solution is that the positioning portion is provided with a nail hole penetrating downward, and a nail body for nailing the prosthesis column into the bone layer is installed in the nail hole.

[0014] A further technical solution is that the nail hole is a threaded hole, and the nail body is a screw with a nail cap.

[0015] A further technical solution is that a plurality of axial grooves are circumferentially arranged on the outer surface of the prosthetic column.

[0016] A further technical solution is that a plurality of micro holes are evenly distributed on the prosthetic column and the upper cover.

[0017] A further technical solution is that the axial directions of the multiple microholes are in multiple directions.

[0018] A further technical solution is that there is an interference fit between the fixing portion and the positioning portion.

[0019] The beneficial effects of adopting the above technical solution are:

[0020] Before implanting the prosthesis component, a Kirschner wire is inserted according to the necrosis of the femoral head to determine the direction of the channel, and then a step drill is used to remove the dead bone in the area, and then a fine bone drill is used to decompress the periphery of the dead bone removal area to establish a bone grafting channel. After the channel is established, the prosthesis column is assembled with the installation handle, and the prosthesis column is placed in the channel along the Kirschner wire. When implanting the prosthesis column, the head of the installation handle can be hammered to embed the prosthesis column into the channel, and the positioning pins at the bottom of the prosthesis column are hammered into the bone layer, so that the prosthesis column can be fixed to the bone. Then the installation handle is taken out, and the top cover is fixedly assembled on the top of the prosthesis column. The upper surface of the top cover is an arc surface that matches the curvature of the femoral head, which is adapted to the defective surface of the femoral head and can better fuse with the femoral head.

[0021] By hammering the installation handle, the force is prevented from acting directly on the prosthesis, thus ensuring the appearance quality of the prosthesis. In addition, the installation handle has a positioning hole that matches the diameter of the Kirschner wire. By hammering the installation handle, the installation handle drives the prosthesis column to move in the same direction as the bone graft channel, thus ensuring the coaxiality of the prosthesis column and the bone graft channel, so that the circumferential direction of the prosthesis column is uniformly restricted by the bone, thus ensuring the circumferential stability of the prosthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] Figure 1 It is a schematic diagram of the structure of the combination of the prosthesis and the femur in the present invention;

[0024] Figure 2 is a schematic diagram of the exploded structure of the prosthesis component of the present invention;

[0025] Figure 3 The structure of the prosthesis column in the present invention is shown in FIG. Figure 1 ;

[0026] Figure 4 The structure of the prosthesis column in the present invention is shown in FIG. Figure 2 ;

[0027] Figure 5 It is a structural schematic diagram of the upper cover in the present invention;

[0028] Figure 6 It is a structural schematic diagram of the installation handle in the present invention. DETAILED DESCRIPTION

[0029] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0030] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] like Figure 1 to Figure 6 As shown, a femoral head partial replacement prosthesis assembly includes a prosthesis column 10 and a top cover 20 that are finally implanted in the femoral head, and also includes a mounting handle 30 used when implanting the prosthesis column 10. The main structure of the femoral neck and femoral head is not destroyed, and only the collapsed or damaged area is locally repaired and filled.

[0032] The cross section of the prosthetic column 10 is circular, and the prosthetic column 10 can be cylindrical or truncated cone-shaped with a thin bottom and a thick top. When the prosthetic column 10 is truncated cone-shaped, the size of its large end is slightly larger than the inner diameter of the bone grafting channel, so that there is a squeezing force between the prosthetic column 10 and the bone grafting channel. The top of the prosthetic column 10 has a convex or concave positioning portion 11 located in its axial direction, and the bottom of the prosthetic column 10 has a plurality of protruding positioning pins 12, and the positioning pins 12, the positioning portion 11 and the main body of the prosthetic column 10 are integrally formed. A plurality of axial grooves are circumferentially arranged on the outer surface of the prosthetic column 10, and the arrangement of the grooves can provide bone cells for growth, so that the prosthetic column 10 is more firmly combined with the bone.

[0033] The top cover 20 is used to cover the top of the prosthetic column 10. The upper surface of the top cover 20 is an arc surface 21 that matches the curvature of the femoral head. The bottom of the top cover 20 has a fixing portion 22 that is concave-convexly fitted with and fixed to the positioning portion 11. The fixing portion 22 and the positioning portion 11 are interference fit, that is, when the fixing portion 22 and the positioning portion 11 are matched, the raised part has a Morse taper, so that the fixing portion 22 and the positioning portion 11 are interference fit, and the two are squeezed against each other to achieve fixation.

[0034] The prosthetic column 10 and the upper cover are evenly distributed with multiple micropores, which can be made using existing micropore 3D printing technology. This pore structure is conducive to the creeping growth of bone cells to cause bone fusion, accelerate the growth of bone and achieve the purpose of long-term stability. And the axial directions of the multiple micropores are preferably multiple directions.

[0035] The prosthesis column 10 and the top cover 20 cooperate to form a complete prosthesis structure, which is made of the same size according to the patient's CT image and other tomographic scanning data and is an implant made of medical metal or medical organic polymer materials such as peek.

[0036] The installation handle 30 is used as an auxiliary tool when installing the prosthesis. The installation handle 30 includes a limit plate 31 that can fit in contact with the top surface of the prosthesis column 10, a handle rod 32 is fixed above the limit plate 31, and a pressing portion 33 that matches the positioning portion 11 is fixed below the limit plate 31. The pressing portion 33 and the positioning portion 11 are matched to ensure that they are coaxial. In addition, after the prosthesis column 10 and the installation handle 30 are assembled, there is a through hole for the Kirschner wire to pass through. The through hole on the installation handle 30 matches the diameter of the Kirschner wire to form a positioning hole 34.

[0037] Before implantation of the prosthesis component, a Kirschner wire is inserted according to the condition of femoral head necrosis to determine the direction of the channel, and then a step drill is used to remove the dead bone in the area, and then a fine bone drill is used to reduce the pressure around the dead bone removal area to establish a bone grafting channel. After the channel is established, the prosthesis column 10 is assembled with the installation handle 30, and the prosthesis column 10 is placed in the channel along the Kirschner wire. When implanting the prosthesis column 10, the head of the installation handle 30 can be hammered to embed the prosthesis column 10 into the channel, and the positioning pin 12 at the bottom of the prosthesis column 10 is hammered into the bone layer, so that the prosthesis column 10 can be fixed to the bone. Then the installation handle 30 and the Kirschner wire are taken out, and the top cover 20 is fixedly assembled on the top of the prosthesis column 10. The upper surface of the top cover 20 is an arc surface 21 that matches the curvature of the femoral head, which is compatible with the defective surface of the femoral head and can better fuse with the femoral head.

[0038] By hammering the installation handle 30, the force is prevented from acting directly on the prosthesis, thereby ensuring the appearance quality of the prosthesis. In addition, the installation handle 30 has a positioning hole 34 that matches the diameter of the Kirschner wire. By hammering the installation handle 30, the installation handle 30 drives the prosthesis column 10 to move in the same direction as the bone grafting channel, thereby ensuring the coaxiality of the prosthesis column 10 and the bone grafting channel, so that the circumferential direction of the prosthesis column 10 is uniformly restricted by the bone, thereby ensuring the circumferential stability of the prosthesis.

[0039] In order to further enhance the fixing strength of the prosthesis, a downwardly penetrating nail hole 13 is provided on the positioning portion 11, in which a nail body for nailing the prosthesis column 10 into the bone layer is installed. The nail hole 13 is a threaded hole, and the nail body is a screw with a nail cap. After the prosthesis column 10 is installed in place, the installation handle 30 is taken out and the nail body is installed. The prosthesis column 10 is nailed into the bone using the nail body, and finally the top cover 20 is installed.

[0040] The above are only preferred embodiments of the present invention. Any simple modification, deformation and equivalent substitution made by anyone to the present invention based on the contents of the present invention shall fall within the protection scope of the present invention.

Claims

1. A femoral head partial replacement prosthesis assembly, characterized in that: include: A prosthetic column (10) having a circular cross section, the top of the prosthetic column (10) having a convex or concave positioning portion (11) located in the axial direction thereof, and the bottom of the prosthetic column (10) having a plurality of protruding positioning pins (12); A top cover (20) covers the top of the prosthetic column (10), wherein the upper surface of the top cover (20) is an arc surface (21) matching the curvature of the femoral head, and a fixing portion (22) is provided at the bottom of the top cover (20) for being concavely and convexly engaged with and fixed to the positioning portion (11); and The mounting handle (30) comprises a limiting plate (31) capable of being in close contact with the top surface of the prosthesis column (10), a handle rod (32) is fixed above the limiting plate (31), and a pressing portion (33) that is concavely matched with the positioning portion (11) is fixed below the limiting plate (31).

2. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: After being assembled, the prosthetic column (10) and the mounting handle (30) have a through hole for the Kirschner wire to pass through, and the through hole on the mounting handle (30) matches the diameter of the Kirschner wire to form a positioning hole (34).

3. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: The positioning portion (11) is provided with a nail hole (13) penetrating downwards, and a nail body for nailing the prosthesis column (10) into the bone layer is installed in the nail hole (13).

4. The femoral head partial replacement prosthesis assembly according to claim 3, characterized in that: The nail hole (13) is a threaded hole, and the nail body is a screw with a nail cap.

5. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: The outer surface of the prosthetic column (10) is circumferentially provided with a plurality of axial grooves.

6. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: The prosthetic column (10) and the upper cover are evenly distributed with a plurality of micropores.

7. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: The axial directions of the plurality of micropores are in a plurality of directions.

8. The femoral head partial replacement prosthesis assembly according to claim 1, characterized in that: The fixing portion (22) and the positioning portion (11) are in interference fit.

Images