CN111297521A - Surface shoulder joint prosthesis - Google Patents

Abstract

The invention belongs to the field of medical instruments and discloses a surface shoulder joint prosthesis which comprises a humerus head prosthesis matched with the shape of a humerus head of a human body, a connecting rod formed on the inner surface of the humerus head prosthesis and a broach detachably connected with the connecting rod, wherein an external thread section is formed on the connecting rod, an internal thread section matched with the external thread section and a first hollow section communicated with the tail end of the internal thread section are formed on the broach, and the external thread section of the connecting rod rotates to enter the first hollow section through the internal thread section and is accommodated and fixed in the first hollow section. The surface shoulder joint prosthesis can be firmly fixed with humerus bone of a human body, has good stability and wide applicability.

Description

A superficial shoulder joint prosthesis

technical field

The invention belongs to the technical field of medical devices, and in particular relates to a surface shoulder joint prosthesis.

Background technique

Traditional artificial shoulder arthroplasty includes humeral head arthroplasty and artificial total shoulder arthroplasty, both of which need to remove the entire humeral head and install a prosthesis, while superficial shoulder arthroplasty only removes a part of the humeral head. The remaining part of the head is sheathed with a surface shoulder joint prosthesis adapted to the shape of the humeral head.

The structure of the existing surface shoulder joint prosthesis includes a humeral head prosthesis adapted to the shape of the surface of the humerus and a medulla needle formed on the inner surface of the humeral head prosthesis. A hole is opened on the humeral head for installing the medullar needle, and the medullar needle of the surface shoulder joint prosthesis is aligned with the hole on the humeral head, and an external force is applied to the prosthesis to make the inner surface of the humeral head prosthesis fit with the outer surface of the human humeral head. touch to complete the installation. In order to ensure the fixation effect, bone cement can also be arranged in the hole opened on the humeral head to facilitate the fixation with the human humerus bone.

Although the existing superficial shoulder joint prosthesis can meet the needs of patients, in actual use, it is found that the medulla needle and the human humerus are taper press fit, and the prosthesis has the risk of taper press fit failure when implanted into the human body and used for a long time. Once the taper press-fit fails, the prosthesis will become free in the body and may cut the nerve. At the same time, the humeral head prosthesis and the pulp needle are integrally formed, and it is easy to cause the phenomenon that the size of the humeral head prosthesis or the pulp needle is not suitable for the same patient.

In view of the defects of the prior art superficial shoulder joint prosthesis, those skilled in the art hope to propose a superficial shoulder joint prosthesis that is firmly fixed to the human humeral head bone, has good stability and has wide applicability.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a surface shoulder joint prosthesis which is firmly fixed to the bone of the human humeral head, has good stability and has wide applicability.

The superficial shoulder joint prosthesis according to the present invention includes a humeral head prosthesis adapted to the shape of the human humeral head, a connecting rod formed on the inner surface of the humeral head prosthesis, and a medulla needle detachably connected with the connecting rod, wherein the connecting rod is on the An external thread segment is formed, an internal thread segment matched with the external thread segment and a first hollow segment communicated with the end of the internal thread segment are formed on the medulla needle, and the external thread segment of the connecting rod is rotated through the internal thread segment to enter the first hollow segment. The hollow section is accommodated and fixed in the first hollow section.

Further, the medulla needle is also formed with a second hollow segment that communicates with the head end of the internal thread segment, and a taper fitting segment between the external thread segment and the inner surface of the humeral head prosthesis is also formed on the connecting rod, wherein, After the external thread segment of the connecting rod passes through the internal thread segment through the second hollow segment and enters the first hollow segment, the taper fitting segment is press-fitted in the second hollow segment.

Furthermore, the outer peripheral wall of the conical segment and/or the inner peripheral wall of the second hollow segment is configured as a rough surface.

Further, the external thread segment is formed at the free end of the connecting rod, and the axial length of the external thread segment is less than or equal to the axial length of the first hollow segment.

Further, the taper fitting segment has an outer diameter dimension that gradually decreases from a first end close to the inner surface of the humeral head prosthesis toward a second end away from the inner surface of the humeral head prosthesis.

Further, the connecting rod is also formed with a transition section between the outer thread section and the taper section, the outer diameter of the transition section is smaller than the outer diameter of the outer thread section, and the outer diameter of the transition section is smaller than the outer diameter of the second end. diameter size.

Further, a plurality of longitudinal ribs distributed circumferentially are formed on the outer surface of the pith needle.

Further, an HA+TI coating is formed on the upper part of the outer surface of the pulp needle, and a porous three-dimensional structure layer is formed on the middle and lower part of the outer surface of the pulp needle.

Further, the inner surface of the humeral head prosthesis is formed with HA+TI coating.

Further, a plurality of anti-rotation protrusions are formed on the inner surface of the humeral head prosthesis.

Preferably, the plurality of anti-rotation protrusions are arranged in a conical shape and are evenly distributed, and the axis of the anti-rotation protrusions forms an included angle with the diameter direction of the humeral head prosthesis.

Compared with the prior art, the superficial shoulder joint prosthesis of the present invention has the following advantages:

1) The humeral head prosthesis and the medulla needle of the surface shoulder joint prosthesis of the present invention can be detachably arranged, so that the most suitable specifications of the humeral head prosthesis and the medullar needle can be selected according to the size of the humeral head of different patients, and it has a wide range of specifications. applicability. At the same time, the surface shoulder joint prosthesis of the present invention realizes the fixed connection between the humeral head prosthesis and the medulla needle through the cooperation of the external thread segment through the internal thread segment and the first hollow segment, that is, after the surface shoulder joint prosthesis is installed, the external thread The segment and the internal thread segment do not maintain the thread fit, but are located in the first hollow segment. This arrangement can prevent the surface shoulder joint prosthesis from loosening due to the thread fit between the external thread segment and the internal thread segment during the movement of the superficial shoulder joint prosthesis. Therefore, the loosening of the humeral head prosthesis and the pulp needle is effectively avoided, and the surface shoulder joint prosthesis of the present invention has a better fixation effect.

2) By forming a second hollow section on the medulla needle that communicates with the head end of the inner thread section, and forming a taper section between the outer thread section and the inner surface of the humeral head prosthesis on the connecting rod, the humeral head prosthesis is formed. In addition to the way of cooperating and fixing the external thread section and the first hollow section, the body and the pulp needle also have the mode of cooperating and fixing the taper section and the second hollow section, which further avoids the loosening between the humeral head prosthesis and the pulp needle. Therefore, the surface shoulder joint prosthesis of the present invention has a better fixation effect.

3) The HA+TI coating is formed on the upper part of the outer surface of the pulp needle, and the middle and lower part of the outer surface of the pulp needle is formed with a porous three-dimensional structure layer, so that the outer surface of the pulp needle has a rough structure, so that human bone is in the pulp needle. The outer surface blends easily and grows easily.

4) By forming a plurality of conical and evenly distributed anti-rotation protrusions on the inner surface of the humeral head prosthesis, and configuring the anti-rotation protrusions to form the axis of the anti-rotation protrusions with the diameter direction of the humeral head prosthesis The included angle makes the humeral head prosthesis connected with the human humeral head, and the anti-rotation protrusion can be inserted into the surface of the human humeral head to prevent the humeral head prosthesis from rotating relative to the human humeral head.

Description of drawings

1 is a cross-sectional view of a superficial shoulder joint prosthesis according to the present invention;

Fig. 2 is the structural representation of the first embodiment of the humeral head prosthesis shown in Fig. 1;

Fig. 3 is the sectional view of the humeral head prosthesis shown in Fig. 2;

FIG. 4 is a schematic structural diagram of the first embodiment of the medulla needle shown in FIG. 1;

5 is a schematic structural diagram of a second embodiment of the medulla needle according to the present invention;

6 is a schematic structural diagram of a second embodiment of the humeral head prosthesis according to the present invention.

Detailed ways

In order to better understand the purpose, structure and function of the present invention, the superficial shoulder joint prosthesis of the present invention will be described in further detail below with reference to the accompanying drawings.

1 shows the structure of a surface shoulder joint prosthesis 100 according to the invention, including a humeral head prosthesis 1 adapted to the shape of a human humeral head, a connecting rod 11 formed on the inner surface of the humeral head prosthesis 1, and a connecting rod 11 formed on the inner surface of the humeral head prosthesis 1 Removably connected medulla needle 2, wherein an external thread segment 111 is formed on the connecting rod 11, and an internal thread segment 23 that cooperates with the external thread segment 111 and a first thread segment that communicates with the end of the internal thread segment 23 are formed on the medulla needle 2. A hollow section 21 , the external thread section 111 of the connecting rod 11 is rotated through the internal thread section 23 to enter the first hollow section 21 , and is accommodated and fixed in the first hollow section 21 .

When the superficial shoulder joint prosthesis 100 of the present invention is used, the bone on the surface of the humeral head of the human body is removed in advance, and a hole for inserting the medulla needle 2 is opened on the surface of the humeral head of the human body. When the surface shoulder joint prosthesis 100 is used, first select the humeral head prosthesis 1 and the medulla needle 2 of the corresponding specifications according to the size of the patient's humeral head, align the connecting rod 11 with the medulla needle 2, and insert the external thread section 11 of the connecting rod 11 through the medulla. The internal thread section 23 of the needle 2 is screwed into the first hollow section 21 and fixed in the first hollow section 21 , so that the humeral head prosthesis 1 and the medulla needle 2 are connected together. Then, align the medulla needle 2 with the hole pre-drilled on the surface of the human humeral head, and apply external force to the humeral head prosthesis 1. The medullar needle 2 gradually penetrates into the hole until the inner surface of the humeral head prosthesis 1 is in contact with the human humerus. The surface of the head is fitted, and the surface shoulder joint prosthesis 100 is well fixed to the human humeral head at this time.

It should be noted that the existing surface shoulder joint prosthesis is generally formed in one piece, that is, the medulla needle and the humeral head prosthesis are not detachable. Although this surface shoulder joint prosthesis has different specifications, the The dimensions of the humeral head prosthesis and the pulp needle of the superficial shoulder joint prosthesis are fixed and invariable. In practical applications, only one of the humeral head prosthesis and the pulp needle of the same specification of the superficial shoulder joint prosthesis can fit. With patients, the superficial shoulder joint prosthesis is prone to loosening after the normal installation of the superficial shoulder joint prosthesis, which affects the later recovery and the service life of the superficial shoulder joint prosthesis. By detaching the humeral head prosthesis 1 and the pulp needle 2, the present application can select the most suitable specifications of the humeral head prosthesis 1 and the pulp needle 2 according to the size of the humeral head of different patients, which has wide applicability. At the same time, the surface shoulder joint prosthesis 100 of the present invention realizes the fixed connection between the humeral head prosthesis 1 and the medulla needle 2 through the cooperation of the external thread segment 111 through the internal thread segment 23 and the first hollow segment 21, that is, the surface shoulder joint prosthesis 1 After the installation is completed, the external thread segment 111 and the internal thread segment 23 do not maintain a thread fit, but are located in the first hollow segment 21. Such a setting can prevent the external thread segment 111 from being damaged during the movement of the superficial shoulder joint prosthesis 100. The loose fit occurs due to the thread fit with the internal thread segment 23, thereby effectively avoiding the loosening of the humeral head prosthesis 1 and the medulla needle 2, and making the surface shoulder prosthesis 100 of the present invention better. Fixed effect.

According to the superficial shoulder joint prosthesis 100 of the present invention, the needle 2 may further be formed with a second hollow section 22 that communicates with the head end of the inner thread section 23, and the connecting rod 11 may be further formed with a second hollow section 22 located between the outer thread section 111 and the end of the inner thread section 23. The taper fitting section 112 between the inner surfaces of the humeral head prosthesis 1, wherein, after the external thread section 111 of the connecting rod 11 passes through the internal thread section 23 through the second hollow section 22 and enters the first hollow section 21, the taper fitting section 112 can be Press fit within the second hollow section 22 . At this time, the process of connecting the humeral head prosthesis 1 and the medulla needle 2 will be: align the connecting rod 11 of the humeral head prosthesis 1 with the medulla needle 2, and the external thread section 111 of the connecting rod 11 will enter the second hollow section in turn 22. The internal thread section 23 and the first hollow section 21 are fixed in the first hollow section 21. During this process, the taper fitting section 112 gradually enters the second hollow section 22 and is press-fitted in the second hollow section within 22. Through this arrangement, the humeral head prosthesis 1 and the medulla needle 2 have a press-fit fixing method of the taper-fitting section and the second hollow section 22 in addition to the fitting and fixing method of the external thread section 111 and the first hollow section 21, which further avoids The loosening between the humeral head prosthesis 1 and the pulp needle 2 is eliminated, so that the surface shoulder joint prosthesis 100 of the present invention has a better fixation effect.

According to the surface shoulder joint prosthesis 100 of the present invention, the outer peripheral wall of the tapered fitting segment 112 and/or the inner peripheral wall of the second hollow segment 22 may be configured as a rough surface. Because the taper-fitting section 112 is press-fitted with the second hollow section 22 , this arrangement makes it difficult for the taper-fitting section 112 to escape from the second hollow section 22 after the taper-fitting section 112 is press-fitted with the second hollow section 22 . In another embodiment, the outer peripheral wall of the conical fitting section 112 and/or the inner peripheral wall of the second hollow section 22 may also be smooth, so that more accurate fitting can be achieved.

In the implementation shown in FIG. 2 , the external thread segment 111 may be formed at the free end of the connecting rod 11 , and the axial length of the external thread segment 111 may be less than or equal to the axial length of the first hollow segment 21 . It should be noted that in this embodiment, the external thread segment 111 is to be matched with the first hollow segment 21 so that the external thread segment 111 is fixed in the first hollow segment 21. Therefore, the axial length of the external thread 111 is less than or equal to the first hollow segment. The axial length of 21 should not only ensure that the external thread segment 111 can be screwed into the first hollow segment 21, but also ensure that the cooperation between the first hollow segment 21 and the external thread segment 111 satisfies the stable connection between the humeral head prosthesis 1 and the medulla needle 2. Require.

2 and 3, the taper fitting section 112 may have an outer diameter that gradually decreases from the first end F close to the inner surface C of the humeral head prosthesis 1 toward the second end G away from the inner surface C of the humeral head prosthesis 1 . Through this arrangement, the contact surface of the conical fitting section 112 is gradually increased when it is gradually fitted with the second hollow section 22, thereby increasing the stability of the structure. At the same time, the compressive stress generated when the patient normally moves the shoulder joint in the future can make the prosthesis more and more The tighter it is, the more stable the superficial shoulder prosthesis is.

As shown in FIG. 1 and FIG. 2 , a transition section 113 between the external thread section 111 and the taper matching section 112 may also be formed on the connecting rod 11 , and the outer diameter of the transition section 113 may be smaller than the outer diameter of the external thread section 111 . size, and the outer diameter of the transition section 113 may be smaller than the outer diameter of the second end G. Since the connection between the humeral head prosthesis 1 and the medulla needle 2 in this embodiment is the cooperation between the external thread segment 111 and the first hollow segment 21, and the cooperation between the taper segment 112 and the second hollow segment 22, the above arrangement makes the The transition section 113 can stably connect the male thread section 111 and the taper section 112, and at the same time, when the male thread section 111 is screwed into the first hollow section 21 of the needle 2, the transition section 113 will not be affected by the second hollow section 22 and the female thread. Segment 23 is stuck.

In one embodiment of the medulla needle 2 as shown in FIG. 4 , a plurality of longitudinal ribs 24 distributed circumferentially may be further formed on the outer surface of the medulla needle 2 . This arrangement can prevent the medulla needle 2 from rotating after being inserted into the human humeral head, and prevent the dislocation of the superficial shoulder joint prosthesis 100 .

As shown in FIG. 4 , an HA+TI coating (a mixed coating of hydroxyapatite and pure titanium) 25 may be formed on the upper part A of the outer surface of the pulp needle 2 , and the middle and lower part B of the outer surface of the pulp needle 2 may be formed with Porous three-dimensional structure layer 26 . The HA+TI coating and the porous three-dimensional structure layer 26 of the pulp needle 2 of the present invention are both formed on the surface of the solid structure of the pulp needle 2, wherein the upper part of the pulp needle 2 is formed with a second hollow section 22, an internal thread section 23 and The first hollow section 21, so the upper part of the outer surface of the pulp needle 2 has a hole structure composed of the second hollow section 22, the inner thread section 23 and the first hollow section 21, which is not a completely closed solid structure, while the pulp needle 2 The middle and lower part of the device is a completely closed solid structure, and the connection between the connecting rod 11 and the medulla needle 2 is connected by a non-completely closed solid structure, so this structure is a force-bearing position, requiring both high strength. . In the prior art, the method of spraying TI coating (pure titanium coating) on the surface of the prosthesis is often used to improve the performance of bone integration. However, TI is an inert metal and lacks osteoinductive ability. When it is in contact with the human physiological environment, it cannot form with bone. Chemically bonded, cannot promote new bone growth. In this embodiment, the HA (hydroxyapatite)+TI coating 25 is formed on the upper part of the outer surface of the pulp needle 2, so that the upper part of the outer surface of the pulp needle 2 has a rough outer surface, and the human bone can attach HA+TI The coating 25 grows, and since HA is the main inorganic component of human bones, it has excellent biological activity and osteoconductivity. Therefore, the HA+TI coating has good biocompatibility and bioactivity on the one hand, and higher binding strength on the other hand. The porous three-dimensional structure layer 26 mentioned here is similar to the porous structure of human bone, for example, it can be a 3D printed bone trabecular structure, which is easy for human bone to grow. It should be noted that, since the porous three-dimensional structure layer is a porous structure, its strength is not high, so the porous three-dimensional structure layer is arranged on the middle and lower part B of the outer surface of the pulp needle 2, that is, the closed solid structure part, to ensure that the pulp needle 2 has higher strength.

In the embodiment shown in FIG. 2 , the inner surface C of the humeral head prosthesis 1 may also be formed with an HA+TI coating. Since the inner surface C of the humeral head prosthesis 1 is in contact with the humeral head of the human body, through this arrangement, the inner surface C of the humeral head prosthesis 1 forms a rough structure, which is easy for human bone to grow.

As shown in FIG. 2 , a plurality of anti-rotation protrusions 12 may also be formed on the inner surface C of the humeral head prosthesis 1 . Through this arrangement, after the humeral head prosthesis 1 is connected with the human humeral head, the anti-rotation protrusion 12 can be inserted into the surface of the human humeral head to prevent the humeral head prosthesis 1 from rotating relative to the human humeral head.

In the embodiment shown in FIG. 3 , a plurality of anti-rotation protrusions 12 can be arranged in a conical shape and evenly distributed, and the axis D of the anti-rotation protrusions 12 can form an included angle α with the direction of the diameter E of the humeral head prosthesis 1 . Through this setting, the axis D of the anti-rotation protrusion 12 and the diameter direction E of the humeral head prosthesis 1 form an included angle α, so the direction of the force of the anti-rotation protrusion on the human humeral head (in the direction of the axis of the anti-rotation protrusion 12 ) ) is not collinear with the force direction (in the direction perpendicular to the diameter E) when the rotation occurs, so that the anti-rotation protrusion 12 is not easy to rotate after being inserted into the human humeral head.

It should be noted that, in the superficial shoulder joint prosthesis 100 of the embodiment of the present invention, since the middle and lower part B of the outer surface of the medulla needle 2 has the porous three-dimensional mechanism layer 26, the upper part A of the outer surface of the medulla needle 2 and the humeral head prosthesis The inner surface C of the body 1 is coated with HA+TI, which can ensure that the human bone is fused with the surface shoulder joint prosthesis 100 and grows well, so it does not need to be fixed with bone cement, and it can also prevent the bone cement from falling off due to future shoulder joint activities. Or fall off with human bones. However, due to the high cost of the medulla needle in the first embodiment in the prior art, it is still relatively common to use bone cement for connection. For this, an application is also shown in the embodiment shown in FIG. 5 . The structure of the medulla needle 2 connected with bone cement, compared with the medulla needle 2 of the embodiment shown in FIG. 4 , the difference between the medulla needle 2 of this embodiment is only that the outer surface is not provided with the HA+TI coating 25 and the porous three-dimensional Structure 26.

In addition, it still needs to be explained that for the symptoms of the humeral head of different patients, the human humeral head of different patients needs to be treated differently, so that the human humeral head from which the superficial bone is removed can have different shapes. For example, the covered humeral head is suitable for patients with hyperostosis, sclerosis and rotator cuff injury of the greater tuberosity, and the covered humeral head prosthesis 1 according to the embodiment shown in FIG. Contact range, the wrap-type humeral head prosthesis shown in FIG. 6 differs from the humeral head prosthesis shown in FIG. 2 only in the shape of the inner surface. It should be noted that, according to different symptoms of the patient's humeral head, the shape of the inner surface of the humeral head prosthesis 1 can also be changed accordingly, which will not be repeated here.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. The scope of the invention should be included in the scope of the claims and description of the present invention. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any manner. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims (10)

1. A surface shoulder joint prosthesis is characterized by comprising a humerus head prosthesis matched with the shape of a humerus head of a human body, a connecting rod formed on the inner surface of the humerus head prosthesis, and a broach detachably connected with the connecting rod, wherein an external thread section is formed on the connecting rod, an internal thread section matched with the external thread section and a first hollow section communicated with the tail end of the internal thread section are formed on the broach, and the external thread section of the connecting rod rotates to enter the first hollow section through the internal thread section and is contained and fixed in the first hollow section.

2. The superficial shoulder joint prosthesis of claim 1, wherein the broach further has a second hollow section formed thereon communicating with a head end of the internal thread section, and the connecting rod further has a tapered section formed thereon between the external thread section and the inner surface of the humeral head prosthesis, wherein the tapered section is press-fitted into the second hollow section after the external thread section of the connecting rod passes through the internal thread section via the second hollow section into the first hollow section.

3. The surface shoulder joint prosthesis of claim 2, wherein the outer peripheral wall of the tapered section and/or the inner peripheral wall of the second hollow section is configured as a roughened surface.

4. The surface shoulder joint prosthesis of claim 2, wherein the externally threaded section is formed at a free end of the connecting rod, the externally threaded section having an axial length that is less than or equal to an axial length of the first hollow section.

5. The facial shoulder joint prosthesis of any one of claims 2-4, wherein the tapered section has an outer diameter dimension that gradually decreases from a first end proximal to the inner surface of the humeral head prosthesis toward a second end distal to the inner surface of the humeral head prosthesis.

6. The surface shoulder joint prosthesis of claim 5, wherein the connecting rod further defines a transition section therebetween, the transition section having an outer diameter dimension less than an outer diameter dimension of the outer threaded section and an outer diameter dimension less than an outer diameter dimension of the second end.

7. The surface shoulder joint prosthesis of any one of claims 1-4, wherein the outer surface of the broach is further formed with a plurality of circumferential longitudinal ribs.

8. The surface shoulder joint prosthesis of any one of claims 1-4, wherein an upper portion of the outer surface of the broach is formed with an HA + TI coating, and a middle-lower portion of the outer surface of the broach is formed with a porous three-dimensional structural layer.

9. The superficial shoulder joint prosthesis of any of claims 1-4, wherein the inner surface of the humeral head prosthesis is formed with an HA + TI coating.

10. The facial shoulder joint prosthesis of claim 9, wherein the inner surface of the humeral head prosthesis is further formed with a plurality of anti-rotation protrusions.

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