Artificial joint prosthesis for semi-hip replacement

Abstract

The utility model relates to an artificial joint prosthesis for semi-hip replacement. The artificial joint prosthesis comprises a bipolar head cup, a femoral head, a C-shaped ring and a femoral stem, the double-pole-head cup comprises a first containing cavity and an inner locking groove. The femoral head comprises a ball head and a second accommodating cavity, and the ball head is arranged in the first accommodating cavity; the C-shaped ring comprises a C-shaped ring body, a ring through hole and a ring notch, the shape of the C-shaped ring is consistent with that of the inner locking groove, and the caput femoris is locked in the first containing cavity through a conical surface formed by elastic deformation; the femoral stem comprises a stem awl, a stem neck and a stem body, the stem awl is arranged in the second accommodating cavity, and the stem body is wedged into the femoral medullary cavity of the human body; and the bipolar head cup is made of ceramic. The C-shaped ring elastically deforms to form a conical surface to lock the femoral head, the problems that a traditional locking mode is poor in locking mode and the femoral head is prone to falling off due to deformation space are solved, a ceramic material is used for replacing a traditional material, and the problem that a traditional artificial joint prosthesis cannot be compatible with friction force in a service environment is solved.

Description

Technical Field

[0001] The utility model relates to the field of medical instruments, in particular to an artificial joint prosthesis used in hemi-hip replacement surgery. Background Art

[0002] For more than 50 years, hemiarthroplasty has been clinically proven to be an effective method for treating displaced femoral neck fractures, with a low incidence of infection and dislocation. In the traditional bipolar head structure, the structure faced during the C-ring assembly process must be assembled by inward deformation. At the same time, it can also be removed by inward deformation. Removal in the locked state requires a certain amount of inward deformation space. This leads to the fact that the outer arc surface of the femoral head ball head and the inner arc surface of the bipolar head cup cannot fit in the traditional bipolar head structure design. The C-ring is mostly made of polyethylene with a very low elastic modulus. During the movement, there is a default space. In this way, the C-ring has a multi-directional deformation space, and its locking method is poor. It is very easy to deform and creep due to local force, resulting in falling off, which in turn causes the femoral head to fall off from the bipolar head cup. The traditional bipolar head is composed of a cobalt-chromium-molybdenum outer cup and a polyethylene liner. The polyethylene liner has a low elastic modulus and is easy to deform. In the double-motion state, it cannot be compatible with the friction caused by the two interface movements in the service environment. Utility Model Content

[0003] The technical problem to be solved by the utility model is that there is a certain deformation space when the C-ring in the prior art locks the bipolar head cup and the femoral head, resulting in a poor locking method, the femoral head is easy to fall off from the bipolar head cup, and the traditional artificial joint prosthesis is not compatible with the friction caused by the two interface movements in the service environment in the dual-motion state.

[0004] In order to solve the problems existing in the prior art, an artificial joint prosthesis for hemiarthroplasty is disclosed, comprising:

[0005] A bipolar head cup, the bipolar head cup is a hemispherical structure, including a bipolar head cup body, a first accommodating cavity and an inner locking groove, the inner locking groove is arranged at the bottom of the bipolar head cup body, and the bipolar head cup body includes an inner spherical surface of the bipolar head cup and an outer spherical surface of the bipolar head cup;

[0006] A femoral head, the femoral head comprising a ball head and a second accommodating cavity, the ball head being placed in the first accommodating cavity of the bipolar head cup;

[0007] A C-shaped ring, the C-shaped ring comprising a C-shaped ring body, a ring through hole and a ring notch, the shape of the C-shaped ring matches the shape of the inner locking groove, the C-shaped ring is placed in the inner locking groove of the bipolar head cup, and the C-shaped ring forms a conical surface through elastic deformation to lock the femoral head in the first accommodating cavity of the bipolar head cup;

[0008] A femoral stem comprises a stem cone, a stem neck and a stem body, wherein the stem cone is placed in the second accommodating cavity, and the stem body is fixed in the medullary cavity with a pre-opened hole in the human femoral bone marrow.

[0009] Furthermore, the ball head includes an outer spherical surface of the femoral head. After the ball head is placed in the bipolar head cup, the outer spherical surface of the femoral head and the inner spherical surface of the bipolar head cup fit each other.

[0010] Furthermore, the C-shaped ring also includes an outer locking surface, an inner arc surface, a first ring end surface and a second ring end surface. The thickness between the outer locking surface and the inner arc surface is constructed to be the thickness of the C-shaped ring. The inner arc surface matches the outer spherical surface of the femoral head, and the first ring end surface and the second ring end surface are arranged opposite to each other.

[0011] Furthermore, the inner locking surface of the inner locking groove fits with the outer locking surface of the C-shaped ring to complete the locking of the femoral head.

[0012] Furthermore, the outer shape of the handle cone matches the shape of the second accommodating cavity. After the handle cone is placed in the second accommodating cavity, the handle cone and the inner conical surface of the second accommodating cavity fit each other.

[0013] Furthermore, the bipolar head cup is placed in the human acetabulum.

[0014] Furthermore, the bipolar head cup is made of ceramic.

[0015] Furthermore, the size of the ring gap is 1 to 2 mm.

[0016] Furthermore, after assembly is completed, the dual-motion interface composed of the inner spherical surface of the bipolar head cup and the outer spherical surface of the femoral head, the outer spherical surface of the bipolar head cup and the human acetabulum is flipped and circumferentially rotated along the meridian and latitude directions.

[0017] The artificial joint prosthesis for hemiarthroplasty of the present invention comprises a bipolar head cup, a femoral head, a C-shaped ring and a femoral stem; the bipolar head cup is a hemispherical structure, comprising a bipolar head cup body, a first accommodating cavity and an inner locking groove, the inner locking groove is arranged at the bottom of the bipolar head cup body, the bipolar head cup body comprises an inner spherical surface of the bipolar head cup and an outer spherical surface of the bipolar head cup; the femoral head comprises a ball head and a second accommodating cavity, the ball head is placed in the first accommodating cavity of the bipolar head cup; the C-shaped ring comprises a C-shaped ring body , annular through hole and annular notch, the shape of the C-shaped ring matches the shape of the inner locking groove, the C-shaped ring is placed in the inner locking groove of the bipolar head cup, and the C-shaped ring forms a conical surface through elastic deformation to lock the femoral head in the first accommodating cavity of the bipolar head cup; the femoral stem comprises a stem cone, a stem neck and a stem body, the stem cone is placed in the second accommodating cavity, and the stem body is fixed in the medullary cavity of the human femoral bone marrow with a pre-opened hole; the ball head comprises an outer spherical surface of the femoral head, and the ball head is placed in the bipolar head cup. After the bipolar head cup is in place, the outer spherical surface of the femoral head fits with the inner spherical surface of the bipolar head cup; the C-shaped ring also includes an outer locking surface, an inner arc surface, a first ring end surface and a second ring end surface, the thickness between the outer locking surface and the inner arc surface is constructed to be the thickness of the C-shaped ring, the inner arc surface matches the outer spherical surface of the femoral head, the first ring end surface and the second ring end surface are arranged opposite to each other, and the second ring end surface is flush with the bottom surface of the bipolar head cup; the inner locking surface of the inner locking groove fits with the outer locking surface of the C-shaped ring , completing the locking of the femoral head; the outer shape of the handle cone matches the shape of the second accommodating cavity, and after the handle cone is placed in the second accommodating cavity, the handle cone and the inner conical surface of the second accommodating cavity fit each other; the bipolar head cup is placed in the human acetabulum; the material of the bipolar head cup is ceramic; the size of the ring notch is 1 to 2 mm, and after the assembly is completed, the double-motion interface composed of the inner spherical surface of the bipolar head cup and the outer spherical surface of the femoral head, the outer spherical surface of the bipolar head cup and the human acetabulum flips along the meridian and latitude directions and moves in a ring.

[0018] The utility model locks the femoral head by forming a conical surface through elastic deformation of the C-shaped ring, thereby solving the problem that when the traditional C-shaped ring locks the bipolar head cup and the femoral head, there is a certain deformation space, which leads to a poor locking method and the femoral head is easy to fall off the bipolar head cup. Ceramic materials are used instead of traditional materials, solving the problem that traditional artificial joint prostheses are not compatible with the friction caused by two interface movements in the service environment in the dual-motion state. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0020] Figure 1It is a schematic diagram of the overall structure of an embodiment of the utility model;

[0021] Figure 2 It is a structural explosion diagram of an embodiment of the utility model;

[0022] Figure 3 This is a cross-sectional view of the bipolar head cup structure of an embodiment of the utility model;

[0023] Figure 4 This is a cross-sectional view of the femoral head structure of an embodiment of the utility model;

[0024] Figure 5 This is a cross-sectional view of the C-shaped ring structure of an embodiment of the utility model;

[0025] Figure 6 This is a cross-sectional view of the femoral stem structure of an embodiment of the utility model;

[0026] Figure 7 It is a schematic diagram of the overall ring movement of an embodiment of the utility model;

[0027] Figure 8 It is a cross-sectional view of the assembled structure of an embodiment of the utility model.

[0028] In the figure, 1-bipolar head cup, 11-bipolar head cup body, 110-inner spherical surface of bipolar head cup, 111-outer spherical surface of bipolar head cup, 12-first accommodating cavity, 13-inner locking groove, 130-inner locking surface; 2-femoral head, 21-ball head, 210-outer spherical surface of femoral head, 22-second accommodating cavity, 220-inner conical surface; 3-C-shaped ring, 31-C-shaped ring body, 310-outer locking surface, 311-first ring end face, 312-second ring end face, 313-inner arc surface, 32-ring through hole, 33-ring notch; 4-femoral stem, 41-stem cone, 42-stem neck, 43-stem body;. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] In order to solve the problems existing in the prior art, the present application provides an artificial joint prosthesis for use in hemiarthroplasty. Figure 1As shown, the artificial joint prosthesis used in hemiarthroplasty includes a bipolar head cup 1, which is a hemispherical structure, including a bipolar head cup body 11, a first accommodating cavity 12 and an inner locking groove 13, wherein the inner locking groove 13 is provided at the bottom of the bipolar head cup body 11, and the bipolar head cup body includes a bipolar head cup inner spherical surface 110 and a bipolar head cup outer spherical surface 111; a femoral head 2, including a ball head 21 and a second accommodating cavity 22, wherein the ball head 21 is placed in the first accommodating cavity 12 of the bipolar head cup 1; C-type The ring 3 comprises a C-shaped ring body 31, a ring through hole 32 and a ring notch 33. The shape of the C-shaped ring 3 matches the shape of the inner locking groove 13. The C-shaped ring 3 is placed in the inner locking groove 13 of the bipolar head cup 1. The C-shaped ring 3 forms a conical surface through elastic deformation to lock the femoral head 2 in the first accommodating cavity 13 of the bipolar head cup 1; the femoral stem 4 comprises a stem cone 41, a stem neck 42 and a stem body 43. The stem cone 41 is placed in the second accommodating cavity 22, and the stem body 43 is fixed in the medullary cavity of the human femoral bone marrow with a pre-opened hole.

[0031] Furthermore, the ball head 21 includes an outer spherical surface 210 of the femoral head. After the ball head 21 is placed in the bipolar head cup 1, the outer spherical surface 210 of the femoral head and the inner spherical surface 110 of the bipolar head cup fit each other.

[0032] Furthermore, the C-shaped ring 3 also includes an outer locking surface 310, an inner arc surface 313, a first ring end surface 311 and a second ring end surface 312. The thickness between the outer locking surface 310 and the inner arc surface 313 is constructed to be the thickness of the C-shaped ring 3. The inner arc surface 313 cooperates with the outer spherical surface 210 of the femoral head, and the first ring end surface 311 and the second ring end surface 312 are relatively arranged; the inner locking surface 130 of the inner locking groove 13 is in contact with the outer locking surface 310 of the C-shaped ring 3 to complete the locking of the femoral head 2. The size of the ring notch 33 is 1 to 2 mm.

[0033] Furthermore, the shape of the handle cone 41 matches the shape of the second accommodating cavity 22. After the handle cone 41 is placed in the second accommodating cavity 22, the handle cone 41 and the inner conical surface 220 of the second accommodating cavity 22 fit each other; the bipolar head cup 1 is placed in the human acetabulum; the material of the bipolar head cup 1 is ceramic.

[0034] Specifically, after assembly is completed, the dual-motion interface composed of the inner spherical surface 110 of the bipolar head cup and the outer spherical surface 210 of the femoral head, the outer spherical surface 111 of the bipolar head cup and the human acetabulum flips and circumferentially along the directions of the meridians 5 and the latitudes 6. It can be understood that the flipping along the directions of the meridians 5 and the latitudes 6 can be specifically understood as the flipping of the ball head 21. In the ball head joint, the ball head 21 part of a bone rotates around its own axis. This movement is similar to the hinge movement of a door. The ball head 21 rotates around its own central axis without leaving the joint groove. Furthermore, the movement along the directions of the meridians 5 and the latitudes 6 can be specifically understood as the circumferential movement of the ball head 21, which is a composite movement of the ball head in the joint groove, including rolling and sliding. In this movement, the spherical head not only rotates around its own axis, but may also undergo slight changes in position in the joint groove, achieving a wider range of motion through rolling and sliding.

[0035] In one example, the ball head 21 is installed into the first accommodating cavity 12 along the inner spherical surface 110 of the bipolar head cup. During installation, the opening direction of the second accommodating cavity 22 is consistent with the opening direction of the first accommodating cavity 12. After the ball head 21 is installed, a first directional force is applied to the C-ring 3, so that the C-ring body 31 produces an elastic deformation in the direction of the ring through hole 32, and the C-ring body 31 is installed into the inner locking groove 13 of the bipolar head cup 1. The C-ring 3 continues to be installed. As the C-ring body 31 is gradually buckled into the inner locking groove 13, the second directional force generated by the outer spherical surface 210 of the femoral head on the C-ring body 31 is the opposite direction of the first directional force, so that the diameter of the inner arc surface 313 of the C-ring gradually increases as it moves inward. In this process, the inner locking surface 130 of the inner locking groove 13 is aligned with the inner circle of the C-ring. The arc surface 313 forms a conical surface with an approximately parallel relationship, which gradually increases in diameter from the second ring end face 312 of the C-shaped ring 3 to the first ring end face 311. At this time, the outer locking surface 310 of the C-shaped ring 3 is in contact with the inner locking surface 130 of the inner locking groove 13, and the outer spherical surface 210 of the femoral head is in contact with the inner arc surface 313 of the C-shaped ring. When the C-shaped ring 3 passes through the diameter of the locking groove 13 in the bipolar head cup, the C-shaped ring 3 can gradually release the elastic deformation of the inward pressure. After the assembly is completed, the first direction force of the C-shaped ring 3 is removed, and the C-shaped ring 3 returns to its natural shape. At this time, the inner locking surface 130 of the inner locking groove 13 and the outer spherical surface 210 of the femoral head form a rigid trumpet mouth with a diameter that gradually decreases from the inside to the outside. The C-shaped ring 3 is buckled into this trumpet mouth to form a self-locking device to firmly lock the femoral head 2 into the bipolar head cup.

[0036] After the artificial prosthesis is assembled, the dual-motion interface composed of the inner spherical surface 110 of the bipolar head cup and the outer spherical surface 210 of the femoral head, the outer spherical surface 111 of the bipolar head cup and the human acetabulum is flipped along the longitude and latitude directions, and rotates in a circle. The C-shaped ring forms two external rotation points during the movement, and an angle is formed between the two external rotation points. The larger the movement angle, the more uniform the force on the artificial prosthesis is, and the greater the resistance generated by the C-shaped ring.

[0037] Furthermore, the size of the ring gap 33 is set to 1-2 mm, which is much smaller than the gap of 4-5 mm in the traditional self-locking method. The small gap is more conducive to the structural strength of the C-shaped ring body 31 itself, making the C-shaped ring 3 less likely to deform.

[0038] Furthermore, the bipolar head cup 1 is made of ceramic material, which is more compatible with the friction caused by the two interface movements in the service environment.

[0039] The utility model locks the femoral head by forming a conical surface through elastic deformation of the C-shaped ring, thereby solving the problem that when the traditional C-shaped ring locks the bipolar head cup and the femoral head, there is a certain deformation space, which leads to a poor locking method and the femoral head is easy to fall off the bipolar head cup. Ceramic materials are used instead of traditional materials, solving the problem that traditional artificial joint prostheses are not compatible with the friction caused by two interface movements in the service environment in the dual-motion state.

[0040] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0041] The above shows and describes the basic principle, main features and advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments, and the above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, and these changes and improvements fall within the scope of the utility model to be protected.

Claims

1. An artificial joint prosthesis for hemiarthroplasty, characterized in that: include: A bipolar head cup (1), the bipolar head cup (1) being a hemispherical structure, comprising a bipolar head cup body (11), a first accommodating cavity (12) and an inner locking groove (13), wherein the inner locking groove (13) is arranged at the bottom of the bipolar head cup body (11), and the bipolar head cup body comprises a bipolar head cup inner spherical surface (110) and a bipolar head cup outer spherical surface (111); A femoral head (2), the femoral head (2) comprising a ball head (21) and a second accommodating cavity (22), the ball head (21) being placed in the first accommodating cavity (12) of the bipolar head cup (1); A C-shaped ring (3), the C-shaped ring (3) comprising a C-shaped ring body (31), a ring through hole (32) and a ring notch (33); the shape of the C-shaped ring (3) matches the shape of the inner locking groove (13); the C-shaped ring (3) is placed in the inner locking groove (13) of the bipolar head cup (1); the C-shaped ring (3) forms a conical surface through elastic deformation to lock the femoral head (2) in the first accommodating cavity (12) of the bipolar head cup (1); A femoral stem (4), the femoral stem (4) comprising a stem cone (41), a stem neck (42) and a stem body (43), the stem cone (41) being placed in the second accommodating cavity (22), and the stem body (43) being fixed in a medullary cavity with a pre-opened hole in the bone marrow of a human femur.

2. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The ball head (21) comprises an outer spherical surface (210) of the femoral head. After the ball head (21) is placed in the bipolar head cup (1), the outer spherical surface (210) of the femoral head and the inner spherical surface (110) of the bipolar head cup fit each other.

3. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The C-shaped ring (3) further comprises an outer locking surface (310), an inner arc surface (313), a first ring end surface (311) and a second ring end surface (312); the thickness between the outer locking surface (310) and the inner arc surface (313) is constructed to be the thickness of the C-shaped ring (3); the inner arc surface (313) cooperates with the outer spherical surface (210) of the femoral head; the first ring end surface (311) and the second ring end surface (312) are arranged relative to each other.

4. The artificial joint prosthesis for hemiarthroplasty according to claim 3, characterized in that: The inner locking surface (130) of the inner locking groove (13) and the outer locking surface (310) of the C-shaped ring (3) fit each other, thereby completing the locking of the femoral head (2).

5. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The outer shape of the handle cone (41) matches the shape of the second accommodating cavity (22); after the handle cone (41) is placed in the second accommodating cavity (22), the handle cone (41) and the inner conical surface (220) of the second accommodating cavity (22) fit each other.

6. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The bipolar head cup (1) is placed in the acetabulum of a human body.

7. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The material of the bipolar head cup (1) is ceramic.

8. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: The size of the ring gap (33) is 1 to 2 mm.

9. The artificial joint prosthesis for hemiarthroplasty according to claim 1, characterized in that: After assembly, the dual-motion interface formed by the inner spherical surface (110) of the bipolar head cup, the outer spherical surface (210) of the femoral head, the outer spherical surface (111) of the bipolar head cup and the human acetabulum flips and circumferentially moves along the meridian (5) and the latitude (6).

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