Femoral stem prosthesis

Abstract

A femoral stem prosthesis comprises a head and neck part, a near-end part and a far-end part which are sequentially connected, the two sides of the near-end part are solid bodies, the middle of the near-end part is a near-end porous body, and the far-end part comprises a hollow far-end shell and a far-end porous body arranged in the far-end shell. The near-end porous body and the far-end porous body are internally provided with pores which are communicated with each other and extend to the surface, so that a porous structure is formed, the elastic modulus of the femoral stem prosthesis is reduced, the problem of uneven stress conduction caused by a stress shielding effect formed by overlarge elastic modulus is avoided, the fracture risk around the prosthesis is reduced, and the fracture resistance of the femoral stem prosthesis is improved. The human health is better protected; meanwhile, the human body structure tissue can grow into the pores, so that the adhesiveness and combination stability between the prosthesis and the human body tissue are met, the manufacturing and using requirements of a coating are omitted, the problem that the integration degree between the prosthesis and the femur is poor due to the fact that the coating is not uniform is solved, and the risk of sterile looseness is greatly reduced.

Description

Technical Field

[0001] The utility model relates to medical equipment, in particular to a structure of a femoral stem prosthesis. Background Art

[0002] A prosthesis is a medical device used for a limb, organ, or tissue in the human body. Among them, the femoral stem prosthesis is an implant used in current orthopedic hip replacement surgery and is suitable for the repair and reconstruction of human hip joint diseases. The femoral stem prosthesis is usually implanted with the femoral head prosthesis and together with the acetabular liner and acetabular cup to form a complete hip prosthesis. The femoral stem prosthesis generally adopts a solid structure. In order to improve the adhesion and bonding stability between the prosthesis and human tissue, the surface of the prosthesis needs to be coated with a specific material. However, the elastic modulus of this prosthesis is large, which can easily lead to uneven stress conduction due to the stress shielding effect, as well as significant bone absorption in the proximal femur, increasing the risk of periprosthetic fractures. In addition, the manufacturing precision of the prosthesis surface coating is limited, and the thickness of the coating is uneven, resulting in poor integration between the prosthesis and the femur, and a greater risk of aseptic loosening. Utility Model Content

[0003] The purpose of the utility model is to provide a femoral stem prosthesis with a porous structure, so as to reduce the elastic modulus of the prosthesis and increase the integration between the prosthesis and the femur.

[0004] The femoral stem prosthesis described in the present invention includes a head and neck portion, a proximal portion and a distal portion connected in sequence, two opposite sides of the proximal portion are solid bodies, a proximal porous body is located between the two solid bodies, and the proximal porous body is provided with pores that are interconnected and extend to the surface of the proximal porous body.

[0005] Furthermore, the head and neck portion includes a cylindrical neck head and a femoral neck connecting the neck head and the proximal portion.

[0006] Furthermore, the femoral stem prosthesis is arc-shaped as a whole.

[0007] Furthermore, the distal portion includes a hollow distal shell and a distal porous body disposed in the distal shell, and the distal porous body is provided with pores that are interconnected and extend to each side surface.

[0008] Furthermore, the distal porous body includes a distal proximal section, a distal middle section, and a distal distal section arranged in sequence from one end adjacent to the proximal end to the other end, and the porosity of the pores of the distal proximal section, the distal middle section, and the distal distal section increases in sequence.

[0009] Further, the porosity of the pores of the distal porous body is greater than the porosity of the pores of the proximal portion.

[0010] Furthermore, the porosity of the pores in the proximal portion is 28.14%, and the porosities of the pores in the proximal distal portion, the middle distal portion, and the distal distal portion are 37.59%, 47.37%, and 57.17%, respectively.

[0011] Furthermore, the proximal porous body includes a plurality of staggered porous rods, the gaps between adjacent porous rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores.

[0012] Furthermore, the distal porous body includes a plurality of staggered porous rods, the gaps between adjacent porous rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores.

[0013] The femoral stem prosthesis described in the present invention has a proximal portion located on a solid body with a solid structure on both the inner and outer sides of the arc. The solid body can make the prosthesis have good structural strength; the middle portion of the proximal portion is a proximal porous body with pores, and the pores on the proximal porous body pass through the arc surface and the interior of the proximal porous body to form a porous structure, thereby reducing the elastic modulus of the femoral stem prosthesis and avoiding the problem of uneven stress conduction caused by the stress shielding effect due to excessive elastic modulus, thereby reducing the risk of fracture around the prosthesis and better protecting human health; at the same time, through the setting of the proximal porous body, human structural tissue can grow into the pores, thereby meeting the adhesion and bonding stability between the prosthesis and human tissue, eliminating the need for coating production and use, avoiding the problem of poor integration between the prosthesis and femur due to uneven coating, and greatly reducing the risk of aseptic loosening. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the femoral stem prosthesis.

[0015] Figure 2 、 3 It is a schematic diagram of the structure of the femoral stem prosthesis without the distal shell.

[0016] Figure 4 yes Figure 2 Schematic diagram of the local structure of the femoral stem prosthesis shown.

[0017] Figure 5 It is a structural diagram of the pore rods and the pores they form. Implementation Method

[0018] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only 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 ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0019] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, top, bottom, inside, outside, vertical, horizontal, longitudinal, counterclockwise, clockwise, circumferential, radial, axial...), then the directional indications are only used to explain the relative position relationship, movement status, etc. between the various components in a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indications will also change accordingly.

[0020] If there are descriptions involving "first" or "second" in the embodiments of the present invention, the descriptions of "first" or "second" are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features specified as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this utility model.

[0021] The utility model provides a femoral stem prosthesis.

[0022] In an embodiment of the present invention, the femoral stem prosthesis includes a head and neck portion, a proximal portion and a distal portion connected in sequence; the head and neck portion includes a cylindrical neck head 1, and a femoral neck 2 connecting the neck head and the proximal portion; two opposite sides of the proximal portion are solid bodies 3, and a proximal porous body 4 is located between the two solid bodies, and the proximal porous body is provided with pores 5 that are interconnected and extend to the surface of the proximal porous body.

[0023] like Figure 1-4 As shown, the femoral stem prosthesis formed by sequentially connecting the head and neck, the proximal end and the distal end is arc-shaped as a whole, which is consistent with the appearance of existing prostheses; wherein, the proximal end is located on both the inner and outer sides of the arc, which are solid bodies with solid structures, and the middle part of the proximal end is a proximal porous body with pores, and the pores on the proximal porous body pass through the arc surface and the interior of the proximal porous body to form a porous structure.

[0024] The femoral stem prosthesis described herein comprises a hollow distal shell 6 and a distal porous body 7 disposed within the distal shell, and the distal porous body is provided with pores 5 that are interconnected and extend to each side surface. This ensures that the outer surface of the distal portion remains a solid structure, while a porous structure is formed inside, thereby reducing the elastic modulus of the distal portion, further avoiding the problem of uneven stress conduction and reducing the risk of fractures around the prosthesis. In addition, the distal porous body 7 includes a distal proximal section 71, a distal middle section 72, and a distal distal section 73, which are arranged in sequence from one end adjacent to the proximal section to the other end, and the porosity of the pores 5 of the distal proximal section, the distal middle section, and the distal distal section increases in sequence and is greater than the porosity of the pores of the proximal section. Specifically, the porosity of the pores 5 of the proximal section can be set to 28.14%, while the porosity of the pores 5 of the distal proximal section, the distal middle section, and the distal distal section can be set to 37.59%, 47.37%, and 57.17% in sequence. Experiments have shown that this can better reduce the absorption of the proximal femoral bone, increase bone integration, and achieve the effect of prosthetic bone ingrowth.

[0025] The femoral stem prosthesis, the proximal porous body 4 and the distal porous body 7 both include a plurality of staggered hole rods 8, the gaps between adjacent hole rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores 5. These pores can be used to further increase the adhesion between the prosthesis and human tissue, and further reduce the elastic modulus of the prosthesis while ensuring structural strength.

[0026] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention specification and drawings under the utility model concept, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A femoral stem prosthesis, comprising a head and neck portion, a proximal portion, and a distal portion connected in sequence, characterized in that: Two opposite sides of the proximal portion are solid bodies (3), a proximal porous body (4) is located between the two solid bodies, and pores (5) are provided in the proximal porous body that are interconnected and extend to the surface of the proximal porous body.

2. The femoral stem prosthesis according to claim 1, characterized in that: The head and neck portion includes a cylindrical neck head (1) and a femoral neck (2) connecting the neck head and the proximal portion.

3. The femoral stem prosthesis according to claim 1, characterized in that: The femoral stem prosthesis is overall curved.

4. The femoral stem prosthesis according to claim 1, characterized in that: The distal portion comprises a hollow distal shell (6) and a distal porous body (7) disposed in the distal shell, wherein the distal porous body is provided with pores (5) that are interconnected and extend to each side surface.

5. The femoral stem prosthesis according to claim 4, characterized in that: The distal porous body (7) comprises a distal proximal section (71), a distal middle section (72), and a distal distal section (73) arranged in sequence from one end adjacent to the proximal end to the other end, and the porosities of the pores (5) of the distal proximal section, the distal middle section, and the distal distal section increase in sequence.

6. The femoral stem prosthesis according to claim 4 or 5, characterized in that: The porosity of the pores (5) of the distal porous body (7) is greater than the porosity of the pores at the proximal end.

7. The femoral stem prosthesis according to claim 6, characterized in that: The porosity of the pores (5) at the proximal end is 28.14%, and the porosities of the pores at the proximal distal end (71), the middle distal end (72), and the distal distal end (73) are 37.59%, 47.37%, and 57.17%, respectively.

8. The femoral stem prosthesis according to any one of claims 1 to 4, characterized in that: The proximal porous body (4) comprises a plurality of staggered porous rods (8), the gaps between adjacent porous rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores (5).

9. The femoral stem prosthesis according to claim 4 or 5, characterized in that: The distal porous body (7) comprises a plurality of staggered porous rods (8), the gaps between adjacent porous rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores (5).

10. The femoral stem prosthesis according to claim 8, characterized in that: The distal porous body (7) comprises a plurality of staggered porous rods (8), the gaps between adjacent porous rods are in the shape of regular tetrahedrons, and the adjacent gaps are interconnected to form pores (5).

Images