CN214104758U

CN214104758U - Closed guide type femoral stem

Info

Publication number: CN214104758U
Application number: CN202022275234.0U
Authority: CN
Inventors: 赵增广
Original assignee: Beijing Zhong An Tai Hua Science & Technology Co ltd
Current assignee: Beijing Zhong An Tai Hua Science & Technology Co ltd
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2021-09-03
Anticipated expiration: 2030-10-13

Abstract

The utility model relates to a closed direction type femoral stem, including the stem body, the stem body divide into near-end handle and distal end pole, the distal end pole is fixed to be set up on the near-end handle, the one end department of keeping away from the near-end handle at the distal end pole is fixed and is provided with elastic support, elastic support sets up along the lateral surface circumference of distal end pole, when the distal end pole is worn to establish in the marrow cavity, elastic support and marrow cavity inside wall butt. The application has the advantages that when the elastic supporting piece is abutted against the inner wall of the medullary cavity, a patient is not easy to feel severe pain, and the phenomenon that the bone side wall is penetrated due to fixation failure is not easy to occur.

Description

Closed guide type femoral stem

Technical Field

The application relates to the field of medical equipment, in particular to a closed guide type femoral stem.

Background

The artificial hip joint replacement is to fix the hip joint prosthesis on the normal bone through bone cement and screw fixation to replace the diseased joint and rebuild the normal function of the hip joint of the patient, which is a mature and reliable treatment method. The hip joint prosthesis femoral stem has a crucial function as an important part in hip joint prosthesis replacement, and the implanted effect directly influences the recovery degree of joint function. The hip joint prosthesis femoral stem is used as a replacement prosthesis built in femoral bone marrow to replace diseased femurs of human bodies, and is mainly fixed by organisms during primary replacement.

The whole body of the biological hip joint prosthesis femoral stem which is mainstream in the market at present is usually made of titanium alloy, one end of the prosthesis close to the heart is a near end, the other end far away from the heart is a far end, and a titanium coating is sprayed on the near end of the hip joint prosthesis femoral stem. When the prosthesis is implanted into the body, the prosthesis is first inserted into the medullary cavity of the bone, and over time the bone structure slowly grows into the pores in the titanium coating. After the bone structure growth is completed, the effect of long-term stable fixation can be achieved. When the femoral stem of the hip joint prosthesis is implanted into the medullary cavity for the first time, if the length of the prosthesis is too short, the prosthesis is easy to be turned inwards or outwards, and the effect after operation is affected. The current common solution is to set the length of the prosthesis longer, which serves as a guide during implantation.

In view of the above-mentioned related technologies, the inventor believes that when a hip joint prosthesis femoral stem with a long length is implanted into a medullary cavity, one end of the prosthesis far away from the heart is easy to contact with the inner side wall of the medullary cavity, and the elastic modulus of titanium alloy is far greater than that of bones, so that thigh pain is easily caused, and the post-operation effect is affected; if fixation fails, it may even penetrate the distal femur, causing serious postoperative complications.

SUMMERY OF THE UTILITY MODEL

In order to improve the phenomenon problem that one end of the prosthesis far away from the heart is easy to contact with the medullary cavity, the thigh pain is easy to cause, and the effect after operation is influenced, the closed guide type femoral stem is provided.

The application provides a closed direction type femoral stem adopts following technical scheme:

the utility model provides a closed direction type femoral stem, includes the stem body, the stem body divide into near end handle and distal end pole, the distal end pole is fixed to be set up on near end handle, the one end department of keeping away from near end handle at the distal end pole is fixed and is provided with elastic support, elastic support sets up along the lateral surface circumference of distal end pole, when the distal end pole is worn to establish in the marrow cavity, elastic support and marrow cavity inside wall butt.

Through adopting above-mentioned technical scheme, the one end that the near-end handle was kept away from to the distal end pole makes between distal end pole and the medullary cavity inner wall at the interval have the space under elastic support piece's support, and the distal end pole is difficult for contacting with the inside wall in medullary cavity. And the elastic modulus of the elastic support member is lower than that of the skeleton, so that when the elastic support member is abutted against the inner wall of the medullary cavity, a patient is not easy to feel severe pain, and the phenomenon that the side wall of the skeleton is penetrated by fixing failure is not easy to occur. The length that the length of distal end pole can set up is a little longer, makes the bone handle body after installing, is difficult for appearing the phenomenon that the false body is turned over or is turned up, and fixed more stable is difficult for influencing the near-end bone and grows into, has effectively improved the fixed fashioned probability of false body.

Optionally, the elastic support member includes at least two unit support members, the unit support members are disposed along the axis of the distal rod, the distance between the side of the unit support member away from the distal rod and the axis of the distal rod is a unit length, and the unit length of the unit support member near the proximal handle is greater than the unit length of the unit support member away from the proximal handle.

Through adopting above-mentioned technical scheme, elastic support spare comprises a plurality of unit support spare, and whole elastic support spare's shape is the toper. When wearing to establish distal end pole, can play the effect of direction, the angle when making the installation of bone handle body is more accurate, and the bone handle body is more stable after implanting, has effectively reduced the fine motion of bone handle body, and the difficult near-end bone that influences grows into.

Optionally, the distal rod and the elastic support are both made of an organic polymer material, and the elastic support is integrally formed on the distal rod.

By adopting the technical scheme, the organic polymer material is selected from materials which are harmless to human bodies, such as polyetheretherketone, ultrahigh polyethylene and the like. Compared with a titanium alloy material, the elastic modulus of the distal rod made of the organic polymer material is lower. When the bone handle body is stressed, the whole near-end handle is not easy to damage the inner side wall of the medullary cavity, and the safety performance is high. And the elastic support piece is integrally formed on the far-end rod, so that the connection is tighter, and the phenomenon that the elastic support piece falls off and becomes loose is not easy to occur.

Optionally, the surface of the proximal handle is sprayed with a titanium coating.

By adopting the technical scheme, the titanium coating is only sprayed on the surface of the proximal handle, and when the bone handle body is implanted into the medullary cavity, the tissues around the proximal handle can grow on the proximal handle more easily, so that the purpose of long-term stable fixation is achieved.

Optionally, the unit supporting pieces are annular, the axis of each unit supporting piece is collinear with the axis of the distal rod, and a gap is formed between every two adjacent unit supporting pieces; the outer diameter of the cell support, which is the smallest distance from the proximal shaft, is larger than the diameter of the medullary cavity.

By adopting the technical scheme, when the bone handle body is implanted into the medullary cavity, the bone handle body is inevitably worn, and then metal ions and abrasive dust particles can be generated. When the distal rod penetrates into the medullary cavity, at least one unit supporting piece can deform and is in interference fit with the inner side wall of the medullary cavity, so that one end of the medullary cavity, far away from the heart, is sealed. Because in the hip joint, the direction of blood flow in the femoral head is usually from the end of the femoral head close to the heart to the end far away from the heart, and then back to the heart. The end of the medullary cavity far away from the heart is sealed, so that most metal ions and abrasive dust particles are difficult to flow into blood and participate in blood circulation, the harmful substances are difficult to diffuse along with the blood, and the health of a human body is well protected.

Optionally, the proximal handle is provided with a mounting groove, and one end of the distal rod adjacent to the proximal handle is inserted into the mounting groove.

Through adopting above-mentioned technical scheme, the distal end pole passes through mounting groove detachable and installs on the proximal handle, its simple structure, and it is convenient to connect.

Optionally, the cross section of the mounting groove is polygonal, a mounting lug is fixedly arranged at one end of the far-end rod adjacent to the near-end handle, the mounting lug is identical to the mounting groove in shape, and the mounting lug is embedded in the mounting groove.

Through adopting above-mentioned technical scheme, the shape of mounting groove sets to the polygon, makes distal end pole install back on the near-end handle, and the position of distal end pole is fixed, is difficult for rotating. The whole bone handle body structure is more stable.

Optionally, the cross section of the end of the mounting lug away from the distal rod is smaller than the cross section of the end of the mounting lug close to the distal rod.

Through adopting above-mentioned technical scheme, the installation lug sets to the platform shape to the one end that the distal end pole was kept away from to the installation lug is minimum, and it can play good guide effect when establishing the installation lug inlay in the mounting groove, and is more swift and convenient during the installation.

Optionally, the end surface of the distal rod at the end far away from the proximal handle is provided with a spherical surface.

By adopting the technical scheme, one end of the distal rod penetrating through the medullary cavity is set to be a smoother curved surface, so that the safety of the distal rod is improved. Even if the bone handle body has the problem of wrong installation position, the phenomenon that the far-end rod fails to be fixed and penetrates through the side wall of the bone is not easy to occur.

Optionally, the diameter of the end of the distal rod distal to the proximal shaft is smaller than the diameter of the end proximal to the proximal shaft.

Through adopting above-mentioned technical scheme, the distal end pole sets to the thick structure of one end thin one end to the one end that distal end pole and near-end handle are connected is thick one end, makes the distal end pole can be easier and accurate penetrate the intramedullary cavity.

In summary, the present application includes at least one of the following beneficial technical effects:

1. when the elastic support is abutted against the inner wall of the medullary cavity, the patient is not easy to feel severe pain, and the phenomenon that the fixation fails to penetrate through the side wall of the skeleton is not easy to occur;

2. the metal ions and abrasive dust particles are not easy to flow into blood and participate in blood circulation, so that the harmful substances are not easy to diffuse along with the blood, and the health of a human body is well protected.

Drawings

Fig. 1 is a schematic structural diagram of the present embodiment.

Fig. 2 is a schematic view of the installation of the stem body.

Description of reference numerals: 1. a stem body; 2. a proximal handle; 21. mounting grooves; 3. a distal stem; 31. a large end face; 32. a small end face; 33. mounting a bump; 4. an elastic support member; 41. a unit support.

Detailed Description

The present application is described in further detail below with reference to figures 1-2.

The embodiment of the application discloses closed direction type femoral stem. Referring to fig. 1, the closed guide type femoral stem includes a stem body 1. The stem body 1 includes a proximal stem 2 made of a titanium alloy and a distal stem 3 made of an organic polymer material. A titanium coating is sprayed on the surface of the proximal shaft 2.

Referring to fig. 1 and 2, the end surfaces of the two ends of the distal rod 3 are not equal in size, and the end surfaces of the two ends of the distal rod 3 are referred to as a large end surface 31 and a small end surface 32, respectively. The mounting lug 33 is integrally formed at the center of the large end face 31, the mounting lug 33 is in a quadrangular frustum pyramid shape, the side face of the mounting lug 33, which is overlapped with the large end face 31, is the largest end of the mounting lug 33, and the end face at the other end is the smallest end. The proximal handle 2 is provided with a mounting groove 21, and the cross section of the mounting groove 21 is equal to the cross section of the mounting lug 33. The included angle between each side of the installation convex block 33 and the minimum end is equal to the included angle between the inner side wall of the installation groove 21 and the bottom surface of the installation groove 21, and the depth of the installation groove 21 is greater than the height of the installation convex block 33.

Referring to fig. 1 and 2, the small end surface 32 of the distal stem 3 is provided as a hemispherical surface. An elastic support 4 is integrally formed on the outer side wall of the distal rod 3, and the elastic support 4 is located adjacent to the small end surface 32. The elastic support 4 includes four annular unit supports 41, and the unit supports 41 are sleeved on the distal rod 3 and are arranged at equal intervals along the axis of the distal rod 3. The outer diameter of the unit support 41 near the small end surface 32 is smaller than the outer diameter of the unit support 41 near the large end surface 31, and the outer diameter of the unit support 41 far from the small end surface 32 is larger than the diameter of the medullary cavity in which the stem body 1 is installed.

The implementation principle of the closed guide type femoral stem in the embodiment of the application is as follows: through setting distal end pole 3 to the longer structure of length, when distal end pole 3 when penetrating the intramedullary cavity, the guide effect is better, is difficult for appearing the phenomenon that the prosthesis is invertd or is turned up, and is fixed more stable. The distal rod 3 is made of an organic polymer material, the elastic modulus of the organic polymer material is lower than that of the bone, and the small end surface 32 is a hemispherical surface, so that when the distal rod 3 is abutted against the inner wall of the medullary cavity, a patient is not easy to feel severe pain, and the phenomenon that the bone side wall is penetrated by fixing failure is not easy to occur.

When the bone stem body 1 is implanted into the marrow cavity, the bone stem body 1 is inevitably worn, and metal ions and abrasive dust particles are generated. When the distal rod 3 penetrates into the medullary cavity, the unit support 41 deforms and is in interference fit with the inner side wall of the medullary cavity, so that the end of the medullary cavity far away from the heart is sealed. Because in the hip joint, the direction of blood flow in the femoral head is usually from the end of the femoral head close to the heart to the end far away from the heart, and then back to the heart. The end of the medullary cavity far away from the heart is sealed, so that metal ions and abrasive dust particles are not easy to flow into blood and participate in blood circulation, and the harmful substances are not easy to diffuse along with the blood, thereby well protecting the health of a human body. And unit support 41 is integrated into one piece on distal end pole 3, connect more closely, the difficult elastic support 4 that appears drops not hard up phenomenon, simultaneously also can be fine the position of restriction distal end pole 3, make between distal end pole 3 and the pulp cavity inner wall at a distance from there is the space, guaranteed the angle of implantation of stem body 1, difficult production fine motion after implanting, be convenient for near end handle 2 peripheral tissue grow to near end handle 2 in the micropore in the titanium coating to reach long-term stable fixed purpose.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A closed guide type femoral stem is characterized in that: including bone handle body (1), bone handle body (1) divide into near end handle (2) and distal end pole (3), distal end pole (3) are fixed to be set up on near end handle (2), the one end department of keeping away from near end handle (2) at distal end pole (3) is fixed to be provided with elastic support spare (4), elastic support spare (4) set up along the lateral surface circumference of distal end pole (3), when distal end pole (3) are worn to establish in the marrow cavity, elastic support spare (4) and marrow cavity inside wall butt.

2. A closed guide type femoral stem according to claim 1, wherein: the elastic support piece (4) comprises at least two unit support pieces (41), the unit support pieces (41) are arranged along the axis of the far-end rod (3), the distance between the side edge of the unit support piece (41) far away from the far-end rod (3) and the axis of the far-end rod (3) is unit length, and the unit length of the unit support piece (41) close to the near-end handle (2) is larger than that of the unit support piece (41) far away from the near-end handle (2).

3. A closed guide type femoral stem according to claim 2, wherein: the far-end rod (3) and the elastic supporting piece (4) are both made of organic polymer materials, and the elastic supporting piece (4) is integrally formed on the far-end rod (3).

4. A closed guide type femoral stem according to claim 3, wherein: the surface of the near-end handle (2) is sprayed with a titanium coating.

5. A closed guide type femoral stem according to claim 4, wherein: the unit supporting pieces (41) are annular, the axis of each unit supporting piece (41) is collinear with the axis of the distal rod (3), and a gap is formed between every two adjacent unit supporting pieces (41); the outer diameter of the unit support (41) at the smallest distance from the proximal shaft (2) is larger than the diameter of the medullary cavity.

6. A closed guide type femoral stem according to claim 1, wherein: the near-end handle (2) is provided with a mounting groove (21), and one end of the far-end rod (3) adjacent to the near-end handle (2) is inserted into the mounting groove (21).

7. A closed guide type femoral stem according to claim 6, wherein: the cross section of mounting groove (21) be the polygon, distal end pole (3) and the adjacent one end department of near-end handle (2) are fixed and are provided with installation lug (33), installation lug (33) shape is the same with mounting groove (21) shape, and installation lug (33) inlay and establish in mounting groove (21).

8. A closed guide type femoral stem according to claim 7, wherein: the cross section of one end of the mounting convex block (33) far away from the far-end rod (3) is smaller than that of one end close to the far-end rod (3).

9. A closed guide type femoral stem according to claim 1, wherein: the end surface of one end of the far-end rod (3) far away from the near-end handle (2) is arranged to be a spherical surface.

10. A closed guide type femoral stem according to claim 9, wherein: the diameter of one end of the far-end rod (3) far away from the near-end handle (2) is smaller than that of one end close to the near-end handle (2).