A femoral stem

Abstract

The present invention discloses a femoral stem, including a main body structure, a bulging structure and an extrusion screw. The main body structure is provided with a blind hole and a movable hole of the bulging structure. The bulging structure includes a bone insertion unit and a connection unit. The connection unit includes a positioning surface and a guide inclined surface. The present invention adopts a combined structural design to cooperate with the main body structure, the bulging structure and the extrusion screw. The extrusion screw is screwed into the through hole and the blind hole. When the guide thread and the positioning thread are connected with each other, the bone insertion unit extends out of the movable hole of the bulging structure and penetrates into the bone. This method of "expanding and extending the protrusion" can effectively increase the stability during installation and fixation. Therefore, there is no need to design a femoral stem with a slender structure, which avoids the femoral stem from being easily broken due to stress concentration. At the same time, the torque is reduced, the strength of the femoral stem is improved, and the service life of the femoral stem is increased.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a femoral stem. Background Art

[0002] Artificial hip replacement surgery is currently commonly used to treat patients who have difficulty walking and living a normal life due to hip injuries and lesions. Among them, femoral head necrosis of the hip joint is a common condition. Artificial hip replacement surgery involves removing the necrotic femoral head, inserting the femoral stem into the patient's femoral medullary cavity through interference, and then fixing it with bone cement. Finally, a ball is installed on the femoral stem to replace the original femoral head.

[0003] However, the traditional femoral stem is fixed with the aid of bone cement during installation, but it is still difficult to achieve stable fixation for patients with osteoporosis. In addition, the traditional femoral stem is relatively slender. If it is implanted in the host body, a secondary operation is required to forcibly pull out the slender femoral stem and perform a revision, which causes great damage to the patient. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a femoral stem, which increases the stability during installation and retention by expanding and extending the protrusion, so there is no need to design a slender femoral stem, which avoids the femoral stem from being easily broken due to stress concentration, and at the same time reduces the moment to improve the strength of the femoral stem and increase the service life of the femoral stem.

[0005] A femoral stem according to an embodiment of the present invention comprises:

[0006] A main body structure, the main body structure comprises a retaining part and a supporting part connected in sequence, a blind hole is provided at the bottom of the retaining part, an inner side wall of the blind hole is provided with an internal thread, an outer side wall of the retaining part is provided with a bulging structure movable hole, the bulging structure movable hole is connected with the blind hole, a through hole is provided on the side wall of the supporting part along the top surface direction of the supporting part, the inner side wall of the through hole has the same internal thread as the blind hole, the through hole is connected with the blind hole and has the same diameter;

[0007] A bulging structure, the bulging structure comprises a bone insertion unit and a connecting unit, the connecting unit is inserted into the movable hole of the bulging structure, the bone insertion unit is arranged on a side of the connecting unit away from the blind hole, a side of the connecting unit close to the blind hole is a connecting surface, the connecting surface comprises a positioning surface, a guiding inclined surface connected to the bottom side of the positioning surface, the guiding inclined surface is inclined from bottom to top along a direction close to the blind hole, the positioning surface is provided with a positioning thread, and the guiding inclined surface is provided with a guiding thread;

[0008] An extrusion screw, wherein the top surface of the extrusion screw is provided with a hexagonal groove, and the outer side wall of the extrusion screw is provided with an external thread, and the external thread is adapted to the internal thread, the positioning thread, and the guide thread. When the guide thread and the positioning thread are mutually matched and connected, the bone insertion unit extends out of the movable hole of the bulging structure.

[0009] The femoral stem according to the embodiment of the present invention has at least the following beneficial effects:

[0010] The femoral stem adopts a combined structural design, and the main structure, the bulging structure and the extrusion screw are used in combination. The extrusion screw is screwed into the through hole and the blind hole. When the guide thread and the positioning thread are connected with each other, the bone insertion unit extends out of the movable hole of the bulging structure and penetrates into the bone. This method of "expanding and extending the bulge" can effectively increase the stability during installation and retention, so there is no need to design a femoral stem with a slender structure, which avoids the femoral stem from being easily broken due to stress concentration, and at the same time reduces the torque, improves the strength of the femoral stem, and increases the service life of the femoral stem.

[0011] According to some embodiments of the present invention, the movable hole of the bulging structure is a "┑"-shaped structure, the left end of which is connected to the blind hole, wherein the horizontal section of the structure is used to place the connection unit, and the vertical section of the structure is used to place the bone insertion unit. The top surface of the blind hole is flush with the top surface of the movable hole of the bulging structure.

[0012] According to some embodiments of the present invention, the retaining portion is a cylindrical structure.

[0013] According to some embodiments of the present invention, the support portion is a curved structure with an arc, and its cross-section is a circle with a diameter that transitions from large to small from top to bottom. The specific arc can be designed according to the angle actually required by the patient's joint. At the same time, the inner wall of the through hole has the same internal thread as the blind hole, which can ensure that there are sufficient threads in the through hole to cooperate with the extrusion screw.

[0014] According to some embodiments of the present invention, the retaining portion and the supporting portion are integrally formed.

[0015] According to some embodiments of the present invention, a cylindrical structure is provided at the lower end of the support portion, and the outer wall of the cylindrical structure has an external thread, which is compatible with the internal thread of the acetabulum cup in hip replacement surgery and is used for retention, so that the femoral stem and the acetabulum cup are tightly connected, ensuring the stability of the hip joint during movement, thereby reducing the occurrence of dislocation accidents.

[0016] According to some embodiments of the present invention, the movable holes of the bulging structure are evenly distributed along the circumference on the outer wall of the retaining portion.

[0017] According to some embodiments of the present invention, the bone insertion unit is a triangular prism structure.

[0018] According to some embodiments of the present invention, the corner on one side of the bone insertion unit is an embedded portion, and the embedded portion faces the outer wall of the retaining portion through the movable hole of the bulging structure, so that when the guide thread and the positioning thread are cooperated and connected with each other, the embedded portion extends out of the movable hole of the bulging structure and penetrates into the bone, wherein the corner consists of a lateral edge and two side surfaces adjacent to the lateral edge.

[0019] According to some embodiments of the present invention, the embedding portion has embedding teeth, and the embedding teeth include "V"-shaped, "W"-shaped or wavy shapes, so as to be more firmly embedded in the bone.

[0020] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0022] Figure 1 is a schematic structural diagram of the main structure of an embodiment of the present invention;

[0023] Figure 2 is a schematic structural diagram of a bulging structure according to an embodiment of the present invention;

[0024] Figure 3 is a schematic structural diagram of an extrusion screw according to an embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of the assembly structure of an embodiment of the present invention before implantation;

[0026] Figure 5 is a schematic diagram of the assembly structure after implantation of an embodiment of the present invention;

[0027] Main structure 100, fixing part 110, bulging structure activity hole 111, blind hole 112, supporting part 120, through hole 121, cylindrical structure 122,

[0028] The bulging structure 200, the bone insertion unit 210, the embedding portion 211, the connecting unit 220, the positioning surface 221, the guiding slope 222,

[0029] Extrusion screw 300 and hexagonal groove 310 . DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0031] In the description of the present invention, it should be understood that descriptions involving orientation, such as orientation or positional relationship indicated as up, down, etc., are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, 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 therefore should not be understood as a limitation on the present invention.

[0032] In the description of the present invention, unless otherwise clearly defined, words such as provided with, installed, connected, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0033] Reference below Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 A femoral stem according to an embodiment of the present invention is described.

[0034] like Figure 1-Figure 5As shown, the femoral stem according to an embodiment of the present invention includes a main structure 100, a bulging structure 200 and an extrusion screw 300. The main structure 100 includes a retaining portion 110 and a supporting portion 120 connected in sequence, a blind hole 112 is provided at the bottom of the retaining portion 110, an inner wall of the blind hole 112 is provided with an internal thread, an outer wall of the retaining portion 110 is provided with a movable hole 111 of the bulging structure 200, the movable hole 111 of the bulging structure 200 is connected with the blind hole 112, a through hole 121 is provided on the side wall of the supporting portion 120 along the top surface direction of the supporting portion 120, the inner wall of the through hole 121 has the same internal thread as the blind hole 112, the through hole 121 is connected with the blind hole 112 and has the same diameter; the bulging structure 200 includes a bone insertion unit 210 and a connecting unit 220, the connecting unit 220 is inserted into the bulging structure 200 movable hole 111, the bone insertion unit 210 is arranged on the side of the connecting unit 220 away from the blind hole 112, and the side surface of the connecting unit 220 close to the blind hole 112 is a connecting surface, which includes a positioning surface 221 and a guiding bevel 222 connected to the bottom side of the positioning surface 221, the guiding bevel 222 is inclined from bottom to top along the direction close to the blind hole 112, the positioning surface 221 is provided with a positioning thread, and the guiding bevel 222 is provided with a guiding thread; the outer wall of the extrusion screw 300 is provided with an external thread, the external thread is adapted to the internal thread, the positioning thread and the guiding thread, and when the guiding thread and the positioning thread are matched and connected with each other, the bone insertion unit 210 extends out of the movable hole 111 of the bulging structure 200. The femoral stem adopts a combined structural design, and the main structure 100, the bulging structure 200 and the extrusion screw 300 are used in combination. The extrusion screw 300 is screwed into the through hole 121 and the blind hole 112. When the guide thread and the positioning thread are connected with each other, the bone insertion unit 210 extends out of the movable hole 111 of the bulging structure 200 and is inserted into the bone. This method of "expanding and extending the bulge" can effectively increase the stability during installation and retention, so there is no need to design a slender femoral stem, which avoids the femoral stem from being easily broken due to stress concentration, and at the same time reduces the torque to improve the strength of the femoral stem and increase the service life of the femoral stem.

[0035] In some embodiments of the present invention, the movable hole 111 of the bulging structure 200 is a “┑”-shaped structure, the leftmost end of which is connected to the blind hole 112 , wherein the horizontal section of the structure is used to place the connecting unit 220 , and the vertical section of the structure is used to place the bone insertion unit 210 .

[0036] In some embodiments of the present invention, the retaining portion 110 is a cylindrical structure.

[0037] In some embodiments of the present invention, the support portion 120 is a curved structure with an arc, and the specific arc can be designed according to the angle actually required by the patient's joint.

[0038] In some embodiments of the present invention, the retaining portion 110 and the supporting portion 120 are integrally formed.

[0039] In some embodiments of the present invention, a cylindrical structure 122 is provided at the lower end of the support portion 120, and the outer wall of the cylindrical structure 122 has an external thread, which is compatible with the internal thread of the acetabular cup in hip replacement surgery and is used for retention, so that the femoral stem and the acetabular cup are tightly connected, ensuring the stability of the hip joint during movement, thereby reducing the occurrence of dislocation accidents.

[0040] In some embodiments of the present invention, the movable holes 111 of the bulging structure 200 are evenly distributed on the outer wall of the retaining portion 110 along the circumference.

[0041] In some embodiments of the present invention, the bone insertion unit 210 is a triangular prism structure.

[0042] In some embodiments of the present invention, the corner on one side of the bone insertion unit 210 is an embedded portion 211, and the embedded portion 211 is directed toward the outer wall of the retaining portion 110 through the movable hole 111 of the bulging structure 200, so that when the guide thread and the positioning thread are connected with each other, the embedded portion 211 extends out of the movable hole 111 of the bulging structure 200 and penetrates into the bone, wherein the corner is composed of a lateral edge and two side surfaces adjacent to the lateral edge.

[0043] In some embodiments of the present invention, the embedding portion 211 has embedding teeth, which are in a “V” shape, a “W” shape, or a wavy shape, so as to be more firmly inserted into the bone.

[0044] Other structures and operations of the femoral stem according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0045] Reference below Figure 1-Figure 5 , a femoral stem according to an embodiment of the present invention is described in detail with a specific embodiment. It is worth noting that the following description is only an exemplary description and is not a specific limitation of the invention.

[0046] like Figure 1-Figure 5As shown, the femoral stem includes a main structure 100, a bulging structure 200 and an extrusion screw 300. The main structure 100 includes a retaining part 110 and a supporting part 120 connected in sequence. The retaining part 110 is a cylindrical structure, and a blind hole 112 is provided at the bottom thereof. The inner wall of the blind hole 112 is provided with an internal thread. The outer wall of the cylinder is provided with four movable holes 111 of the bulging structure 200 in a "┑"-shaped structure along the circumferential direction. The left end blind holes 112 of the movable holes 111 of the bulging structure 200 are connected. The supporting part 120 is an integral curved structure with an arc, and the arc is designed according to the angle of the actual joint requirements of the patient. The side wall of the support part 120 is provided with a through hole 121 connected to the blind hole 112 and having the same diameter along the top surface direction of the support part 120, and the inner side wall of the through hole 121 has the same internal thread as the blind hole 112; the bulging structure 200 includes a bone insertion unit 210 and a connecting unit 220, and the connecting unit 220 is inserted into the movable hole 111 of the bulging structure 200 of the "┑" type structure, wherein the connecting surface in the connecting unit 220 is close to the blind hole 112, and the connecting surface includes a positioning surface 221, and a bottom side connected to the positioning surface 221. The guide bevel 222 is inclined from bottom to top in the direction close to the blind hole 112, the positioning surface 221 is provided with a positioning thread, the guiding bevel 222 is provided with a guiding thread, the bone insertion unit 210 is a triangular prism structure, which is arranged on the side of the connecting unit 220 away from the blind hole 112; the top surface of the extrusion screw 300 is provided with a hexagonal groove 310, and the outer side wall of the extrusion screw 300 is provided with an external thread, the external thread is adapted to the internal thread, the positioning thread and the guiding thread, and the guiding thread and the positioning thread are mutually adapted. When matingly connected, the bone insertion unit 210 extends out of the movable hole 111 of the bulging structure 200, wherein the corner edge on one side of the triangular prism structure (the corner edge is composed of a side edge and two side surfaces adjacent to the side edge) is an embedded portion 211, and the embedded portion 211 passes through the movable hole 111 of the bulging structure 200 toward the outer wall of the retaining portion 110 of the cylindrical structure, so that when the guide thread and the positioning thread are matingly connected to each other, the embedded portion 211 gradually extends out of the movable hole 111 of the bulging structure 200 and slowly penetrates into the bone.

[0047] Specifically, when the femoral stem is used in hip replacement surgery, the main structure 100, four bulging structures 200, and one extrusion screw 300 are prepared before the patient's surgery. During the operation, the patient's hip joint is opened, and after the femoral head is removed, the femoral cavity of the patient is expanded using a bone drill, and then four protruding structures 200 are taken, and the connecting units 220 therein are respectively aligned with the horizontal section of the movable hole 111 of the protruding structure 200, with one side of the connecting surface close to the blind hole 112, the positioning surface 221 at the upper end, and the guiding inclined surface 222 at the lower end, and then the bone insertion unit 210 of the triangular prism structure is placed in the vertical section of the movable hole 111 of the protruding structure 200, and the sharp edge side (i.e., the embedded part 211) passes through the movable hole 111 of the protruding structure 200 toward but not exceeding the outer wall of the retaining part 110 of the cylindrical structure. After the four protruding structures 200 are installed, the retaining part 110 of the main structure 100 is placed in the femoral cavity, and after adjusting the angle of the supporting part 120, the extrusion screw 300 is placed in the through hole 121, the installation tool is placed in the hexagonal groove 310, and the extrusion screw 300 is slowly screwed in. When the guide thread and the positioning thread are connected with each other, the embedded part 211 is slowly squeezed out and passes through the movable hole 111 of the bulging structure 200, exceeds the outer wall of the solid structure, and slowly penetrates into the bone. The depth of penetration into the bone can be selected according to needs to complete the fixation.

[0048] In the description of this specification, the description with reference to the terms "some embodiments" or "examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0049] Although the embodiments of the present invention have been shown and described, it will be appreciated 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 that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A femoral stem, characterized in that: include: A main body structure, the main body structure comprises a retaining part and a supporting part connected in sequence, a blind hole is provided at the bottom of the retaining part, an inner side wall of the blind hole is provided with an internal thread, an outer side wall of the retaining part is provided with a bulging structure movable hole, the bulging structure movable hole is connected with the blind hole, a through hole is provided on the side wall of the supporting part along the top surface direction of the supporting part, the through hole is connected with the blind hole and has the same diameter, the inner side wall of the through hole has the same internal thread as the blind hole, the bulging structure movable hole is a "┑" type structure, and its left end is connected with the blind hole; A bulging structure, the bulging structure comprises a bone insertion unit and a connecting unit, the connecting unit is inserted into the movable hole of the bulging structure, the bone insertion unit is arranged on a side of the connecting unit away from the blind hole, a side of the connecting unit close to the blind hole is a connecting surface, the connecting surface comprises a positioning surface, a guiding inclined surface connected to the bottom side of the positioning surface, the guiding inclined surface is inclined from bottom to top along a direction close to the blind hole, the positioning surface is provided with a positioning thread, and the guiding inclined surface is provided with a guiding thread; An extrusion screw, wherein the top surface of the extrusion screw is provided with a hexagonal groove, and the outer side wall of the extrusion screw is provided with an external thread, and the external thread is adapted to the internal thread, the positioning thread, and the guide thread. When the guide thread and the positioning thread are mutually matched and connected, the bone insertion unit extends out of the movable hole of the bulging structure.

2. The femoral stem according to claim 1, characterized in that: The retaining part is a cylindrical structure.

3. The femoral stem according to claim 1, characterized in that: The support part is a curved structure with an arc, a cylindrical structure is arranged at the lower end of the support part, and an outer wall of the cylindrical structure has an external thread.

4. The femoral stem according to claim 1, characterized in that: The retaining part and the supporting part are integrally formed.

5. The femoral stem according to claim 1, characterized in that: The movable holes of the bulging structure are evenly distributed along the circumference on the outer side wall of the retaining part.

6. The femoral stem according to claim 1, characterized in that: The bone insertion unit is a triangular prism structure.

7. The femoral stem according to claim 6, characterized in that: The corner of one side of the bone insertion unit is an embedding part, and the embedding part faces the outer side wall of the fixing part through the movable hole of the bulging structure.

8. The femoral stem according to claim 7, characterized in that: The embedding portion is provided with embedding teeth, and the embedding teeth include "I" shape, "V" shape, "W" shape or wave shape.

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