Hip prosthesis

Abstract

The invention discloses a hip joint prosthesis, and belongs to the technical field of medical prostheses, the hip joint prosthesis comprises a femoral stem, a metal ball head and an acetabulum, the acetabulum is composed of a full-dome hemispherical acetabulum outer cup and an acetabulum lining which are mutually sleeved, and the top of the femoral stem is provided with a connector through an insertion rod for sleeving the metal ball head; the top of the metal ball head is inserted into the acetabular lining, an anti-rotation structure is arranged between the acetabular outer cup and the acetabular lining, a longitudinal groove is formed in the side wall of the femoral stem to increase the contact area between a bone and the femoral stem, a transverse groove used for preventing a prosthesis from sinking is formed in the inner side of the neck of the femoral stem, an acetabular screw is arranged on the acetabular outer cup in a penetrating mode, and the acetabular screw is connected with the acetabular outer cup. The end of the acetabulum screw is located between the acetabulum outer cup and the acetabulum lining, the acetabulum screw is specifically a titanium alloy self-tapping screw, the top of the acetabulum screw is provided with a cutting groove, the top end of the acetabulum screw is designed to be a blunt end, the outer surface of the femoral stem and the outer surface of the acetabulum outer cup are rough surfaces, and the acetabulum joint is high in strength and stability and low in abrasion rate.

Description

Technical Field

[0001] The present invention relates to the technical field of medical prostheses, and more particularly to hip prostheses. Background Art

[0002] In the field of modern medicine, hip replacement surgery has gradually lost its mystery and become a relatively common type of surgical operation. However, how to ensure that the femoral stem of the artificial hip joint is firmly fixed in the femoral medullary cavity and maintain long-term stability is a key problem that the academic community has been working hard to overcome. With the rapid development of industrial technology, the field of artificial hip joints has witnessed wave after wave of innovation tides, and new hip joint products have emerged like mushrooms after a spring rain. Currently, the mainstream hip prostheses on the market are mainly divided into two categories: biological and cemented.

[0003] Cemented hip joints have a long application history, and years of clinical data have verified that they can maintain a long service life in the body. However, their shortcomings are also very obvious. When using cement to fix the prosthesis, heat will be released during the solidification process, which is extremely easy to scald the surrounding bone tissue. Moreover, over time, problems such as debris generated by cement wear and its own fatigue aging will not only cause inflammation but also make revision a high probability event, bringing a secondary burden to the patient's body and mind.

[0004] Biological hip joints have great advantages in the actual operation of surgery. They take a short time, significantly reducing the time a patient stays on the operating table. They are highly safe, reducing the risk of unexpected situations during the operation. They have less trauma, quick postoperative recovery, and inconspicuous scars. They are also cost-friendly, reducing the economic pressure on patients. Particularly importantly, they abandon the use of bone cement, completely avoiding the adverse reactions caused by bone cement and eliminating the worry of damage to bone quality caused by subsequent revision and secondary surgery.

[0005] As disclosed in a Chinese patent with the publication number CN205626193U, a biological hip joint is provided, which includes an acetabular cup and a femoral stem. The femoral stem includes a proximal end and a distal end connected by threads. A femoral head is provided on one side of the proximal end away from the distal end. The distal end has an elliptical cross-section, is hollow inside, and has a plurality of micropores on its wall. The acetabular cup includes an inner liner and an outer liner that are snap-connected to each other. The outer liner is fixed in the acetabulum, and the femoral head cooperates with the inner surface of the inner liner. An elastic member is provided between the femoral head and the femoral stem. A reinforcing frame is provided inside the distal end. At least one groove is provided on the outer surface of the femoral stem along the length direction. The reinforcing frame improves the compressive performance of the femoral stem. The groove helps to discharge impurities such as gas and blood in the femoral medullary cavity. The snap connection between the inner liner and the outer liner makes the structure simple and compact, and the use effect is good. One proximal end can be matched with distal ends of different lengths and different external dimensions, and the proximal end can be reused, reducing costs and having strong versatility. This patent improves the compressive performance of the femoral stem by designing a reinforcing frame and discharges impurities by providing grooves on the femoral stem, effectively preventing the internal pressure of the medullary cavity from increasing and reducing the incidence of fat embolism syndrome. However, the stability of the overall structure is not good enough and there is still room for improvement.

[0006] As disclosed in a Chinese patent with the publication number CN204814287U, a biological hip joint is provided, which includes an acetabular prosthesis, a ball head, a femoral neck, and an articular prosthesis. The ball head is located inside the acetabular prosthesis. One end of the femoral neck is connected to the ball head, and the other end of the femoral neck is connected to the proximal end of the articular prosthesis. The distal end of the articular prosthesis is used to be inserted into the femoral medullary cavity. The cross-section of the proximal end of the articular prosthesis is an elliptical structure, the proximal end of the articular prosthesis is a hollow structure, the distal end of the articular prosthesis is a sheet-like structure, and a long strip hole is provided on the distal end of the articular prosthesis. The distal end of the articular prosthesis is a needle-like structure, which has the advantages of being easy to implant into the femoral medullary cavity, being stable after implantation, effectively resisting rotation, and preventing loosening between the articular prosthesis and the bone mass, and has the function of inducing the growth of bone cells. However, its stability still needs to be further improved, and there is still room for improvement in the stability of the biological hip joint. In view of this, the present application is proposed. Summary of the Invention

[0007] Therefore, the present invention provides a hip joint prosthesis to solve the above-mentioned problem of insufficient stability. The outer acetabular cup and the femoral stem are made of titanium alloy, with a rough surface and a HA coating design, having excellent bone integration and bone ingrowth. The acetabular inner liner is made of imported ultra-high molecular weight polyethylene, with a 10° high-edge design, effectively preventing the risk of dislocation. The longitudinal grooves provided on the femoral stem can improve the rotational stability and increase the contact area between the bone and the prosthesis. The transverse grooves can effectively prevent the prosthesis from sinking after installation, optimize the proximal load conduction, and improve the stability.

[0008] The present invention provides the following technical solution: A hip joint prosthesis, which includes a femoral stem, a metal ball head, and an acetabulum, constituting the basic structure of the hip joint prosthesis. During actual use, the acetabulum is inserted into the acetabular fossa of the human body, and the femoral stem is inserted into the femur of the human body. The femoral stem and the acetabulum are connected by the metal ball head to form a relatively stable rotating structure, replacing the original hip joint of the human body. The acetabulum is composed of an acetabular outer cup and an acetabular liner that are sleeved with each other. The surface of the acetabular outer cup is roughened and then sprayed with an HA coating design to ensure firm bone ingrowth and good long-term fixation effect. The full-dome hemispherical design of the acetabular outer cup has better stress conduction and a low wear rate. The overall hemispherical design has a 2mm peripheral protrusion to avoid soft tissue irritation. The top of the femoral stem is installed with a connecting head through a plugging rod. The connecting head adopts the internationally common 12 / 14 standard taper for the socketing of the metal ball head, and is locked through taper fit, which can ensure the stability and firmness of the metal ball head connected to the femoral stem, preventing postoperative dislocation or loosening. The top of the metal ball head is plugged into the acetabular liner. There is an anti-rotation structure between the acetabular outer cup and the acetabular liner. The setting of the anti-rotation structure further improves the stability of this prosthesis, and at the same time can also reduce wear and has a longer service life. A longitudinal groove is provided on the side wall of the femoral stem to increase the contact area between the bone and the femoral stem. A transverse groove for preventing the prosthesis from sinking is provided on the inner side of the neck of the femoral stem. By providing a longitudinal groove on the femoral stem to increase the contact area between the bone and the prosthesis, the rotational stability of this prosthesis is effectively improved. The provided transverse groove can increase the resistance to the downward movement of the prosthesis, effectively avoiding the sinking of the prosthesis after installation, optimizing the proximal load conduction, and improving the stability.

[0009] As a preferred solution of the present invention, an acetabular screw is penetrated through the acetabular outer cup, and the end of the acetabular screw is located between the acetabular outer cup and the acetabular liner. During actual use, after the inside of the human acetabular fossa is processed, the acetabular outer cup can be inserted into the acetabular fossa, and then the acetabular screw is penetrated through the acetabular outer cup and drilled into the acetabular fossa to fix the acetabular outer cup.

[0010] As a preferred solution of the present invention, the acetabular screw is specifically a titanium alloy self-tapping screw, and the top of the acetabular screw has a cutting groove, and the top end is designed as a blunt head. The titanium alloy material has high strength to ensure connection stability. The cutting groove at the top makes the drilling of the acetabular screw smoother and improves the surgical efficiency to a certain extent.

[0011] As a preferred embodiment of the present invention, the materials of the femoral stem and the acetabular outer cup are both titanium alloy. The outer surfaces of the femoral stem and the acetabular outer cup are both rough surfaces and have a HA coating. The femoral stem and the acetabular outer cup are made of high-strength titanium alloy. At the same time, after the outer surface is roughened, a HA coating is sprayed, so that the prosthesis has excellent bone integration and bone ingrowth, and can improve biocompatibility and fatigue strength to a certain extent, and reduce the elastic modulus, which is suitable for prosthesis implantation.

[0012] As a preferred embodiment of the present invention, the anti-rotation structure between the acetabular outer cup and the acetabular liner is specifically a clamping groove opened in the acetabular outer cup and a clamping protrusion arranged on the outer surface of the acetabular liner. The acetabular outer cup and the acetabular liner are fixed in position by the structure of the clamping protrusion being snapped into the clamping groove. With the cooperation of the clamping groove and the clamping protrusion, the acetabular liner has a stable connection state when being installed in the acetabular outer cup, avoiding rotation between the two, improving the stability of the overall structure and reducing the wear rate at the same time.

[0013] As a preferred embodiment of the present invention, the material of the acetabular liner is polyethylene and has a 10° high-edge design. The acetabular liner is made of imported ultra-high molecular weight polyethylene. At the same time, a 10° high-edge is designed, which can make the metal ball be more fully wrapped after being installed, reducing the risk of dislocation during use.

[0014] As a preferred embodiment of the present invention, the material of the metal ball head is cobalt-chromium alloy, which is made of cobalt-chromium alloy with ultra-high strength and hardness. The outer surface is mirror-polished, so that the metal ball head maintains a good rotating state after being installed in the acetabular liner, significantly reducing wear, having a stable structure and a long service life.

[0015] As a preferred embodiment of the present invention, the connecting head adopts the internationally common 12 / 14 standard taper and is locked through taper fit, which can ensure the stability and firmness of the connection between the metal ball head and the femoral stem, preventing postoperative dislocation or loosening.

[0016] The beneficial effects of the present invention are as follows: 1. The acetabular outer cup of the present invention is made of high-strength titanium alloy, with a rough surface and a HA coating design, having excellent bone integration and bone ingrowth. The full-dome hemispherical design has better stress conduction and a lower wear rate. The femoral stem is made of precision-forged titanium alloy, which can effectively improve biocompatibility, fatigue strength, and reduce the elastic modulus. The acetabular liner is made of imported ultra-high molecular weight polyethylene with a 10° high-edge design, effectively preventing the risk of dislocation. The metal ball head is made of cobalt-chromium alloy with ultra-high strength and hardness, and the outer surface is mirror-polished, significantly reducing wear.

[0017] 2. The femoral stem design of the present invention reduces the lateral shoulder, is applicable to traditional surgeries and minimally invasive surgeries. The fully HA coating induces rapid bone growth. The longitudinal grooves provided on the femoral stem can improve rotational stability, increase the contact area between bone and prosthesis, and the transverse grooves can effectively prevent sinking after the prosthesis is installed, optimize proximal load conduction, and improve stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] Figure 1 is a schematic diagram of the overall structure of the present invention; Figure 2 is an exploded view of the structure of the present invention; Figure 3 is a front view of the present invention; Figure 4 is a schematic diagram of the structure of the acetabular liner in the present invention; Figure 5 is a schematic diagram of the structure of the acetabular outer cup in the present invention; Figure 6 is a schematic diagram of the structure of the femoral stem in the present invention.

[0020] Legend: 1. Femoral stem; 101. Insertion rod; 102. Longitudinal groove; 103. Transverse groove; 2. Connector; 3. Metal ball head; 4. Acetabular liner; 401. Clamping protrusion; 5. Acetabular outer cup; 501. Clamping groove; 6. Acetabular screw. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Specific embodiments are given below.

[0023] Such as Figures 1-6As shown, the hip joint prosthesis includes a femoral stem 1, a metal ball head 3, and an acetabulum, which are the basic structure of the hip joint prosthesis. During actual use, the acetabulum is inserted into the acetabular fossa of the human body, and the femoral stem 1 is inserted into the femur of the human body. The femoral stem 1 and the acetabulum are connected by the metal ball head 3 to form a relatively stable rotating structure, replacing the original hip joint of the human body. The acetabulum is composed of an acetabular outer cup 5 and an acetabular liner 4 that are sleeved with each other. The surface of the acetabular outer cup 5 is roughened and then sprayed with a HA coating design to ensure firm bone ingrowth and good long-term fixation effect. The all-dome hemispherical design of the acetabular outer cup 5 has better stress conduction and a low wear rate. The overall hemispherical design has a 2mm peripheral protrusion to avoid soft tissue irritation. The top of the femoral stem 1 is installed with a connecting head 2 through a plugging rod 101. The connecting head uses the internationally common 12 / 14 standard taper for the socketing of the metal ball head 3. Locking is achieved through taper fit, which can ensure the stability and firmness of the metal ball head 3 connected to the femoral stem 1, preventing postoperative dislocation or loosening. The top of the metal ball head 3 is inserted into the acetabular liner 4. There is an anti-rotation structure between the acetabular outer cup 5 and the acetabular liner 4. The setting of the anti-rotation structure further improves the stability of this prosthesis, and at the same time can also reduce wear and has a longer service life. A longitudinal groove 102 is opened on the side wall of the femoral stem 1 to increase the contact area between the bone and the femoral stem 1. A transverse groove 103 for preventing the prosthesis from sinking is opened on the inner side of the neck of the femoral stem 1. By setting the longitudinal groove 102 on the femoral stem 1, the contact area between the bone and the prosthesis is increased, effectively improving the rotational stability of this prosthesis. The set transverse groove 103 can increase the resistance to downward movement of the prosthesis, effectively avoiding the sinking of the prosthesis after installation, optimizing proximal load conduction, and improving stability.

[0024] An acetabular screw 6 is penetrated through the acetabular outer cup 5. The end of the acetabular screw 6 is located between the acetabular outer cup 5 and the acetabular liner 4. During actual use, after the inside of the human acetabular fossa is processed, the acetabular outer cup 5 can be inserted into the acetabular fossa, and then the acetabular screw 6 is passed through the acetabular outer cup 5 and drilled into the acetabular fossa to fix the acetabular outer cup 5.

[0025] The acetabular screw 6 is specifically a titanium alloy self-tapping screw, and the top of the acetabular screw 6 has a cutting groove, and the top end is a blunt head design. The titanium alloy material has high strength to ensure connection stability. The cutting groove at the top makes the drilling of the acetabular screw 6 smoother, improving the surgical efficiency to a certain extent. The blunt head design is relatively round and not as sharp as a pointed screw. Therefore, when the acetabular screw is drilled into the acetabular fossa, it can effectively reduce the pressure concentration of the screw on the bone, reducing the risk of bone cracking and damage, and can protect the prosthesis and the human bone from being torn while ensuring the fixation strength, which is beneficial to the postoperative recovery of the patient.

[0026] The materials of the femoral stem 1 and the acetabular outer cup 5 are both titanium alloy. The outer surfaces of the femoral stem 1 and the acetabular outer cup 5 are both rough surfaces and have a HA coating. The femoral stem 1 and the acetabular outer cup 5 are made of high-strength titanium alloy. At the same time, after the outer surface is roughened, a HA coating is sprayed, so that this prosthesis has excellent bone integration and bone ingrowth, and can improve biocompatibility and fatigue strength to a certain extent, and reduce the elastic modulus, which is suitable for prosthesis implantation.

[0027] The anti-rotation structure between the acetabular outer cup 5 and the acetabular liner 4 is specifically a clamping groove 501 opened in the acetabular outer cup 5 and a clamping protrusion 401 provided on the outer surface of the acetabular liner 4. The acetabular outer cup 5 and the acetabular liner 4 are fixed in position by the structure that the clamping protrusion 401 is inserted into the clamping groove 501. With the cooperation of the clamping groove 501 and the clamping protrusion 401, the acetabular liner 4 has a stable connection state when it is installed in the acetabular outer cup 5, avoiding rotation of the two, improving the stability of the overall structure and reducing the wear rate at the same time.

[0028] The material of the acetabular liner 4 is polyethylene and has a 10° high-edge design. The acetabular liner 4 is made of imported ultra-high molecular weight polyethylene. At the same time, a 10° high-edge is designed, which can make the metal ball be more fully wrapped after being installed, reducing the risk of dislocation during use.

[0029] The material of the metal ball head 3 is cobalt-chromium alloy, which is made of cobalt-chromium alloy with ultra-high strength and hardness. The outer surface is mirror-polished, so that the metal ball head 3 maintains a good rotating state after being installed in the acetabular liner 4, significantly reducing wear, having a stable structure and a long service life.

[0030] The connecting head 2 adopts the internationally common 12 / 14 standard taper and is locked through taper fit, which can ensure the stability and firmness of the connection between the metal ball head and the femoral stem, preventing postoperative dislocation or loosening.

[0031] Working principle: Through surgery, the human femoral head is removed from the acetabular fossa, then the femoral head and femoral neck are resected, and then the acetabular fossa is ground and trimmed. After that, this prosthesis can be installed. Specifically, first install the acetabular outer cup 5 into the acetabular fossa, then drill the tip of the acetabular screw 6 through the acetabular outer cup 5 and into the acetabular fossa to fix the acetabular outer cup 5, and then install the acetabular liner 4, so that the clamping protrusion 401 of the acetabular liner 4 is inserted into the clamping groove 501 of the acetabular outer cup 5, thereby realizing the position fixation of the two, avoiding deflection during later use and improving the structural stability.

[0032] Then, holes are drilled in the human femur, the femoral stem 1 is inserted into the hole, the connector 2 is sleeved on the insertion rod 101, the metal ball head 3 is inserted into the connector 2, and finally the metal ball head 3 is moved into the acetabular liner 4, thus realizing the installation and fixation of the prosthesis. Compared with traditional hip joint prostheses, the acetabular outer cup 5 of the hip joint prosthesis provided by the present invention is made of high-strength titanium alloy, with a rough surface and a HA coating sprayed design, having excellent bone integration and bone ingrowth. The full-dome hemisphere design has better stress conduction and a lower wear rate. The femoral stem 1 is made of precision-forged titanium alloy, which can effectively improve biocompatibility, fatigue strength, and reduce the elastic modulus. The acetabular liner 4 is made of imported ultra-high molecular weight polyethylene, with a 10° high-edge design, effectively preventing the risk of dislocation. The metal ball head 3 is made of ultra-high strength and hardness cobalt-chromium alloy, with a mirror-polished outer surface, significantly reducing wear. The femoral stem 1 is designed to reduce the outer shoulder, suitable for traditional surgery and minimally invasive surgery. The full HA coating induces rapid bone growth. The longitudinal groove 102 provided on the femoral stem 1 can improve rotational stability and increase the contact area between the bone and the prosthesis, while the transverse groove 103 can effectively prevent the prosthesis from sinking after installation, optimize proximal load conduction, and improve stability.

[0033] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A hip joint prosthesis, comprising a femoral stem (1), a metal ball head (3) and an acetabulum, wherein the acetabulum is composed of a full-dome hemispherical acetabulum outer cup (5) and an acetabulum liner (4) which are sleeved together, the top of the femoral stem (1) is mounted with a connector (2) through a plug-in rod (101) for sleeve connection of the metal ball head (3), and the top of the metal ball head (3) is inserted into the acetabulum liner (4), characterized in that: An anti-rotation structure is provided between the acetabular outer cup (5) and the acetabular inner liner (4); a longitudinal groove (102) is provided on the side wall of the femoral stem (1) to increase the contact area between the bone and the femoral stem (1); and a transverse groove (103) is provided on the inner side of the neck of the femoral stem (1) to prevent the prosthesis from sinking.

2. The hip joint prosthesis according to claim 1, characterized in that: An acetabular screw (6) is inserted into the acetabular outer cup (5), and an end of the acetabular screw (6) is located between the acetabular outer cup (5) and the acetabular inner liner (4).

3. The hip joint prosthesis according to claim 2, characterized in that: The acetabular screw (6) is specifically a titanium alloy self-tapping screw, and the top of the acetabular screw (6) has a cutting groove, and the top end is a blunt head design.

4. The hip joint prosthesis according to claim 1, characterized in that: The outer surfaces of the femoral stem (1) and the acetabular outer cup (5) are both rough and have an HA coating.

5. The hip joint prosthesis according to claim 1, characterized in that: The anti-rotation structure between the acetabular outer cup (5) and the acetabular liner (4) specifically comprises a snap-in groove (501) provided in the acetabular outer cup (5) and a snap-in protrusion (401) provided on the outer surface of the acetabular liner (4); the acetabular outer cup (5) and the acetabular liner (4) are fixed in position by a structure in which the snap-in protrusion (401) is snapped into the snap-in groove (501).

6. The hip joint prosthesis according to claim 1, characterized in that: The femoral stem (1) and the acetabulum outer cup (5) are both made of titanium alloy.

7. The hip joint prosthesis according to claim 1, characterized in that: The acetabulum liner (4) is made of polyethylene and has a 10° high edge design.

8. The hip joint prosthesis according to claim 1, characterized in that: The material of the metal ball head (3) is cobalt-chromium alloy.

9. The hip joint prosthesis according to claim 1, characterized in that: The connector (2) adopts the internationally accepted 12 / 14 standard taper.

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