Acetabular cup and acetabular prosthesis applied to hip joint revision

Abstract

The utility model provides an acetabular cup and an acetabular prosthesis which are applied to rebuilding a hip joint. The acetabular cup comprises an acetabular cup body and an acetabular wing formed by extending outwards from the acetabular cup body, the acetabular cup body comprises a hemispherical shell, a plurality of mounting holes formed close to the opening end of the hemispherical shell, a holding hole formed in the top end of the hemispherical shell and a plurality of screw holes located between the mounting holes and the holding hole, the plurality of mounting holes are distributed along the circumference, and the extension directions of each mounting hole and each screw hole are different; the acetabular wing comprises an acetabular wing body arranged close to the opening end of the hemispherical shell and two concave holes longitudinally penetrating through the acetabular wing body, and the two concave holes are used for installing universal screws. According to the acetabular cup provided by the utility model, the fixing strength and the initial stability of the acetabular cup can be improved by adopting a fixing mode of combining the single wing with the universal screw, so that the service life of the acetabular prosthesis is prolonged.

Description

Technical Field

[0001] The utility model belongs to the technical field of medical equipment, and in particular relates to an acetabular cup and an acetabular prosthesis used for hip joint revision. Background Art

[0002] Reconstruction of acetabular bone defects is an important challenge in hip revision surgery.

[0003] The acetabular prosthesis used in hip joint revision usually includes an acetabular cup and a liner. The liner is installed in the acetabular cup, and the liner and the acetabular cup are usually connected by a locking method, that is, a groove is set in the acetabular cup, a protrusion is set on the liner, and the liner is hammered into the acetabular cup so that the protrusion enters the groove.

[0004] The existing technology uses acetabular cups including Jumbo acetabular cups and Ringfix clasps for larger bone defects, and uses traditional acetabular screws to fix the acetabular cup to increase the stability of the acetabular cup. However, traditional acetabular screws rely on the side of the head to contact the surface of the acetabular cup to fix the acetabular cup. The contact area of ​​the side of the screw head and the acetabular cup is small, and the stress at the contact site is too concentrated, which can easily lead to fixation failure and reduce the stability of the acetabular cup. In addition, this side contact positioning can easily form a large shear force, causing the screw to loosen and fail, requiring the acetabular screw to be re-implanted, thereby increasing the patient's pain, reducing the efficiency of the operation, and increasing medical costs. Utility Model Content

[0005] The utility model aims to provide an acetabular cup with a circle of mounting holes and acetabular wings, which can provide more options for screw implantation angles when used in hip joint revision, thereby increasing the stability of the connection between the acetabular cup and the host bone and thus improving the service life of the acetabular prosthesis.

[0006] To achieve the above-mentioned purpose, the utility model provides an acetabular cup for hip joint revision, comprising:

[0007] An acetabular cup body, the acetabular cup body comprising a hemispherical shell, a plurality of mounting holes arranged near the open end of the hemispherical shell, a holding hole opened at the top of the hemispherical shell, and a plurality of screw holes located between the plurality of mounting holes and the holding holes, wherein the plurality of mounting holes are arranged along a circumference and the extending directions of each mounting hole and each screw hole are different;

[0008] An acetabular wing, the acetabular wing is formed by extending from the hemispherical shell toward a direction away from the center of the hemispherical shell, the acetabular wing includes an acetabular wing body arranged near the open end of the hemispherical shell, and two recessed holes longitudinally penetrating the acetabular wing body, the two recessed holes are used for mounting on a universal screw, wherein the acetabular wing body includes a first wing portion horizontally extending from the outer surface of the hemispherical shell toward a direction away from the center of the hemispherical shell, and a second wing portion bent and extended from the end of the first wing portion toward a direction close to the outer surface of the hemispherical shell, and the thickness of the second wing portion is greater than the thickness of the first wing portion.

[0009] In a specific embodiment, the thickness of the first wing portion gradually increases from the hemispherical shell toward the second wing portion.

[0010] In a specific embodiment, the first wing portion includes a lower surface located in the same plane as the opening end of the hemispherical shell, and an upper surface arranged opposite to the lower surface, and the second wing portion includes a first surface connected to the lower surface, and a second surface connected to the upper surface, and the angle between the first surface and the lower surface, and the angle between the second surface and the upper surface are both obtuse angles.

[0011] In a specific embodiment, the second wing portion further includes a third surface having two ends respectively connected to the first surface and the second surface, and one end of the two recessed holes is located on the lower surface and the first surface and the other end is located on the second surface and the third surface.

[0012] In a specific embodiment, central axes of the two recessed holes are parallel to each other.

[0013] In a specific embodiment, the holding hole is a threaded hole, and the projection of the center of the holding hole onto the plane where the opening end of the hemispherical shell is located coincides with the center of the hemispherical shell.

[0014] In a specific embodiment, the inner surface of the hemispherical shell is a smooth surface, and the outer surface of the hemispherical shell is formed into a rough surface by coating, and the plurality of pores on the rough surface are evenly distributed.

[0015] The utility model also provides an acetabular prosthesis, comprising:

[0016] An acetabular cup, wherein the acetabular cup is the acetabular cup described above;

[0017] A holding rod, the holding rod being mounted in the holding hole to place the acetabular cup in the acetabulum;

[0018] A connecting component, comprising a plurality of first connecting screws correspondingly installed in some of the mounting holes, a plurality of second connecting screws correspondingly installed in some of the screw holes, and two universal screws correspondingly installed in two recessed holes, wherein the plurality of first connecting screws, the plurality of second connecting screws and the two universal screws all extend from the inside to the outside of the corresponding holes to connect the acetabular cup to the host bone.

[0019] In a specific embodiment, the acetabular prosthesis is a biological prosthesis, the plurality of mounting holes are nail holes, and the first connecting screw is an ordinary screw.

[0020] In a specific embodiment, the acetabular prosthesis is a bone cement prosthesis, the plurality of mounting holes are universal screw recesses, and the first connecting screw is a universal screw.

[0021] The beneficial effects of the utility model include at least:

[0022] 1. The acetabular cup used for hip joint revision provided by the utility model comprises an acetabular cup body and an acetabular wing extending outward from the acetabular cup body, wherein the acetabular cup body is provided with a holding hole, a plurality of mounting holes and a plurality of screw holes, and the extension directions of each mounting hole and each screw hole are different, and the acetabular wing is provided with a concave hole for cooperating with a universal screw, so that, on the one hand, the mounting hole, the holding hole and the screw hole are all used to provide a mounting position for the screw, and the extension directions of each hole are different, so that more screw implantation directions can be provided, which is convenient for the screw to be fixed to the remaining host bone at a better angle, so that the initial stability of the acetabular cup installation is good; on the other hand, the provision of the acetabular wing increases the contact area between the acetabular cup and the host bone, and the acetabular wing is fixed to the host bone by the universal screw, which does not lose strength and allows the screw to be adjusted in all directions, and the fixing angle of the screw can be adjusted according to the patient's bone anatomy and surgical conditions, so as to flexibly cope with complex clinical situations, and reduce complications caused by poor screw implantation directions while ensuring effective fixation.

[0023] 2. The acetabular cup provided by the utility model for hip joint revision is only provided with one acetabular wing. The fixing method of combining a single wing (one acetabular wing) with a universal screw can increase the fixing strength and initial stability of the acetabular cup, increase the anti-rotation ability, make the micro-motion between the acetabular cup and the host bone very small, promote bone ingrowth, and thus increase the service life of the acetabular prosthesis.

[0024] 3. Finite element analysis has shown that the stress and shear force of the acetabular cup provided by the present invention for hip joint revision are less than those of the HDR prosthesis provided by the prior art, indicating that the connection between the acetabular prosthesis provided by the present invention and the host bone is more stable.

[0025] In addition to the above-described purposes, features and advantages, the present invention has other purposes, features and advantages. The present invention will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of a three-dimensional structure of an acetabular cup for hip joint revision provided by an embodiment of the utility model at one angle;

[0027] Figure 2 A schematic diagram of the three-dimensional structure of an acetabular cup for hip joint revision provided by an embodiment of the utility model at another angle;

[0028] Figure 3 A schematic diagram of a three-dimensional structure of an acetabular prosthesis for hip joint revision provided by another embodiment of the utility model at one angle;

[0029] Figure 4 A schematic diagram of the three-dimensional structure of an acetabular prosthesis for hip joint revision provided by another embodiment of the utility model at another angle;

[0030] Figure 5 A schematic diagram of the structure of an acetabular prosthesis for hip joint revision provided by the utility model placed in the acetabulum;

[0031] Figure 6 The utility model is provided for the schematic diagram of the acetabular prosthesis used for hip joint revision to fill the defect of the acetabulum bottom surface. DETAILED DESCRIPTION

[0032] The following is a detailed description of the embodiments of the present invention in conjunction with the accompanying drawings, but the present invention can be defined and covered by a variety of different implementations according to the claims.

[0033] See also Figure 1 and Figure 2 The utility model provides an acetabular cup 10 for hip joint revision, which is used for reconstruction of acetabular bone defects. Due to the existence of acetabular bone defects, when installing the acetabular cup 10, it is necessary to achieve a firm initial stability between the acetabular cup 10 and the remaining host bone.

[0034] The acetabular cup 10 for hip joint revision provided by the utility model comprises an acetabular cup body 11 and an acetabular wing 12 extending outward from the acetabular cup body 11. The acetabular cup body 11 is placed in the acetabulum to fill the defect. The acetabular wing 12 is used to assist in increasing the stability of the connection between the acetabular cup body 11 and the acetabulum. The acetabular cup body 11 and the acetabular wing 12 are both fixedly connected to the host bone by screws.

[0035] Preferably, the acetabular cup body 11 and the acetabular wing 12 are made of completely the same material and are integrally formed.

[0036] The acetabulum cup body 11 includes a hemispherical shell 111, a plurality of mounting holes 112 arranged near the open end of the hemispherical shell 111, a holding hole 113 opened at the top of the hemispherical shell 111, and a plurality of screw holes 114 located between the plurality of mounting holes 112 and the holding holes 113, wherein the plurality of mounting holes 112 are arranged along a circle and the extension directions of each mounting hole 112 and each screw hole 114 are different.

[0037] In this embodiment, the mounting holes, holding holes and screw holes are all used to provide mounting positions for screws, and the extension directions of the various holes are different, thereby providing more screw implantation directions, making it easier for the screws to be fixed to the remaining host bone at a better angle, thereby improving the initial stability of the acetabular cup installation.

[0038] In specific applications, a finite element model can be established based on the hip joint CT image of the case, and then the extension directions of the mounting holes, holding holes and screw holes can be designed based on the finite element model.

[0039] Preferably, the inner surface of the hemispherical shell is a smooth surface, and the outer surface of the hemispherical shell 111 is formed into a rough surface by coating.

[0040] Preferably, the plurality of pores on the rough surface of the hemispherical shell 111 are evenly distributed.

[0041] Preferably, the porosity of the rough surface of the hemispherical shell 111 is 40% to 70%.

[0042] Porosity is usually expressed as a percentage, which refers to the proportion of the total volume of the material that is void. For example, a material with a porosity of 40% means that 40% of the total volume of the material is void or pores. In the case of the acetabular cup, a constant porosity means that the coating has uniformly distributed pores, which is designed to help bone cells grow into these pores, thereby promoting bone integration of the implant and improving its stability.

[0043] In this embodiment, the hemispherical shell 111 includes a first portion connected to the acetabular wing 12 and a second portion with two ends respectively connected to the first portion, and a plurality of mounting holes 112 are evenly distributed in the second portion.

[0044] In this embodiment, the number of the mounting holes 112 is 7.

[0045] In this embodiment, the plurality of mounting holes 112 are arranged along the circumference, i.e., are designed in a "ring" shape. On the one hand, more screw installation positions and implantation angles can be provided. On the other hand, the shear force and stress on the acetabular cup can be reduced, thereby solving the problem that the stress and shear force on the acetabular cup are currently too concentrated, which can easily lead to fixation failure.

[0046] In this embodiment, the plurality of mounting holes 112 are common nail holes or universal screw recesses. When the acetabular prosthesis including the acetabular cup is a biological prosthesis, the plurality of mounting holes are nail holes for mounting common screws. When the acetabular prosthesis including the acetabular cup is a bone cement prosthesis, the plurality of mounting holes are universal screw recesses for mounting universal screws.

[0047] Preferably, the projection of the center of the holding hole 113 onto the plane where the opening end of the hemispherical shell 111 is located coincides with the center of the hemispherical shell 111 .

[0048] The holding hole 113 is used to install a holding rod, and after the holding rod is fixed to the acetabulum, the installation position of the acetabulum cup is determined.

[0049] By adjusting the tilt angle of the holding rod, the position of the acetabular cup body in the acetabulum can be fine-tuned, and the shear force and stress distribution of the acetabular cup can be changed.

[0050] In this embodiment, the holding hole 113 is a threaded hole.

[0051] Preferably, the plurality of screw holes 114 are evenly arranged in a ring shape, and the plurality of screw holes 114 and the plurality of mounting holes 112 are staggered.

[0052] The misaligned setting here can be understood as the mounting hole and the screw hole are not located on the same curve with one end being the top of the hemispherical shell and the other end being located at the open end of the hemispherical shell.

[0053] In this embodiment, a screw hole 114 is disposed above the middle position of each two mounting holes 112. Here, the above can be understood as the direction toward the holding hole 113.

[0054] The acetabular wing 12 is formed to extend from the hemispherical shell 11 in a direction away from the center of the hemispherical shell 111 and is used to assist in fixing the acetabular cup body 11 to improve the stability of the fixation between the acetabular cup 10 and the host bone.

[0055] It can be understood that, compared with the acetabular cup 10 having only the acetabular cup body, the provision of the acetabular wing 12 increases the contact area between the acetabular cup 10 and the host bone, thereby improving the stability of the fixation between the acetabular cup 10 and the host bone.

[0056] The acetabular wing 12 includes an acetabular wing body 121 disposed adjacent to the open end of the hemispherical shell 111 , and two recessed holes 122 longitudinally penetrating the acetabular wing body 121 . The two recessed holes 122 are used for mounting universal screws.

[0057] In this embodiment, the concave hole opened on the acetabular wing body is designed to be a hole matching the universal screw, so that the universal screw can be installed. The universal screw fixation does not lose strength, and the screw can be adjusted in all directions. The fixing angle of the screw can be adjusted according to the patient's bone anatomy and surgical conditions, and the clinical complex situation can be flexibly responded to. While ensuring effective fixation, the complications caused by the improper screw implantation direction can be reduced.

[0058] Preferably, the acetabular wing body 121 includes a first wing portion 1211 extending horizontally from the outer surface of the hemispherical shell 111 toward the center of the hemispherical shell 111, and a second wing portion 1212 extending and bending from the end of the first wing portion 1211 toward the outer surface of the hemispherical shell 111, and the thickness of the second wing portion 1212 is greater than the thickness of the first wing portion 1211.

[0059] Preferably, the thickness of the first wing portion 1211 gradually increases from the hemispherical shell 111 to the second wing portion 1212 .

[0060] Preferably, the first wing 1211 includes a lower surface 121A located in the same plane as the opening end of the hemispherical shell 111, and an upper surface 121B arranged opposite to the lower surface 121A, and the second wing 1212 includes a first surface 122A connected to the lower surface 121A, and a second surface 122B connected to the upper surface 121B, and the angle between the first surface 122A and the lower surface 121A, and the angle between the second surface 122B and the upper surface 121B are both obtuse angles.

[0061] Preferably, the second wing 1212 also includes a third surface 122C whose two ends are respectively connected to the first surface 122A and the second surface 122B, and one end of the two recessed holes 122 is located on the lower surface 121A and the first surface 122A and the other end is located on the second surface 122B and the third surface 122C.

[0062] Preferably, central axes of the two recessed holes 122 are parallel to each other.

[0063] In the utility model, only one acetabular wing is provided, and the concave hole on the acetabular wing is a universal screw concave hole, so that the rotation advantage of the acetabular cup is maintained while the contact area between the acetabular cup and the host bone is increased.

[0064] Please refer to Figures 1 to 4 The utility model also provides an acetabular prosthesis 100 for hip joint revision, comprising an acetabular cup 10, a holding rod, and a connecting assembly 30, wherein the acetabular cup 10 is the acetabular cup described above, the holding rod is installed in the holding hole 113 of the acetabular cup 10 to place the acetabular cup 10 in the acetabulum, and the connecting assembly 30 is used to be installed in the mounting hole, screw hole and concave hole of the acetabular cup 10.

[0065] In this embodiment, the holding rod is a threaded rod with a nut.

[0066] The connecting assembly 30 includes a plurality of first connecting screws 31 correspondingly installed in the partial mounting holes 112, a plurality of second connecting screws 32 correspondingly installed in the partial screw holes 114, and two universal screws 33 correspondingly installed in the two recessed holes 122. The plurality of first connecting screws 31, the plurality of second connecting screws 33 and the two universal screws 33 all extend from the inside to the outside of the corresponding holes to connect the acetabular cup 10 to the host bone.

[0067] Preferably, the acetabular prosthesis 100 is a biological prosthesis, the plurality of mounting holes 112 are nail holes, and the first connecting screws 31 are ordinary screws.

[0068] Preferably, the acetabular prosthesis 100 is a bone cement prosthesis, the plurality of mounting holes 112 are universal screw recessed holes, and the first connecting screw 31 is a universal screw.

[0069] In this embodiment, the mounting hole 112, the holding hole 113, the screw hole 114 and the recessed hole 122 all include conical holes, and the nuts of the holding rod, the first connecting screw, the second connecting screw and the universal screw are all accommodated in the conical holes, that is, the nuts of the holding rod, the first connecting screw, the second connecting screw and the universal screw do not extend out of the inner side of the hemispherical shell.

[0070] It can be understood that the acetabular prosthesis 100 used for hip joint revision also includes an acetabular liner, etc. The acetabular liner has the same structure as that provided by the prior art, and the present invention does not improve its structure. The innovation of the present invention lies in improving the structure of the acetabular cup and adding or improving the connecting components corresponding to the improved points of the acetabular cup to make the connection between the acetabular cup and the host bone more stable, thereby increasing the service life of the acetabular prosthesis 100.

[0071] The acetabular prosthesis 100 is applied to a specific patient as follows:

[0072] A biological acetabular prosthesis or a bone cement acetabular prosthesis is selected according to the patient's bone defect. An acetabular cup of a suitable type is selected based on the diameter of the patient's acetabulum. When the selected acetabular prosthesis is a biological acetabular prosthesis, it is necessary to place a suitable abduction angle, anteversion angle and acetabular wing position to test the initial stability. Then, a holding rod is connected to the central holding hole of the acetabular cup, and the acetabular cup is driven into the acetabulum until the outer surface of the acetabular cup fits the bone surface. Then, the first connecting screw is screwed into a suitable mounting hole, the second connecting screw is screwed into a suitable screw hole, the universal screw is screwed into the concave hole, and then the acetabular liner is placed. When the selected acetabular prosthesis is a bone cement acetabular prosthesis, it does not need to be placed according to the traditional abduction angle and anteversion angle. The acetabular cup can be placed at the position where the contact area with the host bone is the largest. When placing the liner, a suitable abduction angle and anteversion angle are selected. At this time, the liner needs to be bonded with expensive cement to connect the acetabular cup.

[0073] See also Figure 5 and Figure 6 ,in, Figure 5 A schematic diagram of the application of the acetabular prosthesis placed in the acetabulum with the acetabular wing facing the ilium; Figure 6 Schematic diagram of an acetabular prosthesis filling the defect on the bottom surface of the acetabulum. At this time, the acetabular wing fits the acetabular rim and ilium.

[0074] The utility model also establishes a finite element model of the acetabular prosthesis and imports the finite element model into the Ansysworkbench finite element analysis software package. By applying loads to simulate the normal gait cycle and single-leg static standing, the stress condition of the acetabular cup is analyzed. The finite element results show that the stress and shear force of the acetabular cup provided by the utility model are less than those of the HDR prosthesis provided by the prior art, indicating that the acetabular prosthesis provided by the utility model has a more stable connection with the host bone and a longer service life.

[0075] The above contents are further detailed descriptions of the present invention in combination with specific preferred implementations, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions and substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. An acetabular cup for hip joint revision, characterized in that: include: An acetabular cup body, the acetabular cup body comprising a hemispherical shell, a plurality of mounting holes arranged near the open end of the hemispherical shell, a holding hole opened at the top of the hemispherical shell, and a plurality of screw holes located between the plurality of mounting holes and the holding holes, wherein the plurality of mounting holes are arranged along a circumference and the extending directions of each mounting hole and each screw hole are different; An acetabular wing, the acetabular wing is formed by extending from the hemispherical shell toward a direction away from the center of the hemispherical shell, the acetabular wing includes an acetabular wing body arranged near the open end of the hemispherical shell, and two recessed holes longitudinally penetrating the acetabular wing body, the two recessed holes are used for mounting on a universal screw, wherein the acetabular wing body includes a first wing portion horizontally extending from the outer surface of the hemispherical shell toward a direction away from the center of the hemispherical shell, and a second wing portion bent and extended from the end of the first wing portion toward a direction close to the outer surface of the hemispherical shell, and the thickness of the second wing portion is greater than the thickness of the first wing portion.

2. The acetabular cup for hip joint revision according to claim 1, characterized in that: From the hemispherical shell toward the second wing, the thickness of the first wing gradually increases.

3. The acetabular cup for hip joint revision according to claim 2, characterized in that: The first wing portion includes a lower surface located in the same plane as the opening end of the hemispherical shell, and an upper surface arranged opposite to the lower surface. The second wing portion includes a first surface connected to the lower surface, and a second surface connected to the upper surface. The angle between the first surface and the lower surface, and the angle between the second surface and the upper surface are both obtuse angles.

4. The acetabular cup for hip joint revision according to claim 3, characterized in that: The second wing portion further includes a third surface having two ends connected to the first surface and the second surface respectively, and one end of the two concave holes is located on the lower surface and the first surface and the other end is located on the second surface and the third surface.

5. The acetabular cup for hip joint revision according to any one of claims 1 to 4, characterized in that: The central axes of the two recessed holes are parallel to each other.

6. The acetabular cup for hip joint revision according to claim 1, characterized in that: The holding hole is a threaded hole, and the projection of the hole center of the holding hole onto the plane where the opening end of the hemispherical shell is located coincides with the sphere center of the hemispherical shell.

7. The acetabular cup for hip joint revision according to claim 1, characterized in that: The inner surface of the hemispherical shell is a smooth surface, and the outer surface of the hemispherical shell is formed into a rough surface by coating, and a plurality of pores on the rough surface are evenly distributed.

8. An acetabular prosthesis for hip joint revision, characterized in that: include: An acetabular cup, wherein the acetabular cup is the acetabular cup according to any one of claims 1 to 7; A holding rod, the holding rod being mounted in the holding hole to place the acetabular cup in the acetabulum; A connecting component, comprising a plurality of first connecting screws correspondingly installed in some of the mounting holes, a plurality of second connecting screws correspondingly installed in some of the screw holes, and two universal screws correspondingly installed in two recessed holes, wherein the plurality of first connecting screws, the plurality of second connecting screws and the two universal screws all extend from the inside to the outside of the corresponding holes to connect the acetabular cup to the host bone.

9. The acetabular prosthesis for hip joint revision according to claim 8, characterized in that: The acetabular prosthesis is a biological prosthesis, the plurality of mounting holes are nail holes, and the first connecting screw is an ordinary screw.

10. The acetabular prosthesis for hip joint revision according to claim 8, characterized in that: The acetabular prosthesis is a bone cement prosthesis, the plurality of mounting holes are universal screw recessed holes, and the first connecting screw is a universal screw.

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