CN218652141U - 3D printing thumb carpometacarpal joint trans-prosthesis - Google Patents

Abstract

The utility model provides a 3D prints reverse false body of thumb carpometacarpal joint relates to medical instrument's technical field. The 3D printing thumb carpometacarpal joint trans-prosthesis comprises a carpal ball, a metacarpal cap and a metacarpal rod; the bottom of the carpal ball is provided with a connecting seat, and the connecting seat can be connected with the trapezium and the trapezium through a threaded connecting piece; the metacarpal cap is arranged on the carpal ball, and a pin shaft is arranged between the metacarpal cap and the carpal ball; the metacarpal bone rod which can be placed in the metacarpal bone is arranged on one side of the metacarpal bone cap, which is far away from the carpal ball. The technical effect of good use effect is achieved.

Description

3D printed thumb carpal metacarpal joint trans prosthesis

technical field

The utility model relates to the technical field of medical devices, in particular to a 3D printed thumb carpal metacarpal joint trans prosthesis.

Background technique

Thumb carpometacarpal joint (CMC1) can perform movements such as flexion and extension, adduction, abduction, and rotation, and is the joint with the largest amount of movement in the hand. In daily life, under the action of the special saddle-shaped articular surface and the dorsal ligament of the thumb, the wrist-metacarpal joint of the thumb often bears greater pressure when grasping. Diseases that require the implantation of the thumb carpometacarpal joint prosthesis include: 1. Non-inflammatory degenerative thumb carpometacarpal joint diseases, including osteoarthritis, post-traumatic arthritis, etc. 2. Rheumatoid arthritis. 3. Patients who failed other treatments.

For these diseases, there are a variety of clinical surgical methods, such as: arthroscopic synovial resection, arthroscopic trapezoid resection and ligament reconstruction, first metacarpal base wedge osteotomy, simple trapezoid resection or tendon mass packing, wrist Metacarpal joint fusion, prosthetic replacement or interstitial filling, etc.

Thumb carpometacarpal prostheses come in many forms and come in many types. For total thumb carpometacarpal joint replacement prosthesis, there are metal-metal interface prosthesis such as Elektra and Motec, metal-polymer polymer interface prosthesis such as Arpe and Moovis, and ceramic prosthesis such as Moje Acamo. Patents for full thumb carpal metacarpal joint prosthesis, among which, Rubis II is a metal-metal interface anti-first metacarpophalangeal joint prosthesis. These prostheses are implanted into the trapezoid bone through screws or spiral embolisms, and then implanted into the metacarpal bone through the metacarpal rod, so as to preserve and improve the range of motion of the thumb carpal metacarpal joint and relieve pain.

Prostheses such as Elektra and Arpe use a metal-highly cross-linked polyethylene or metal-metal interface. Compared with the normal thumb carpal metacarpal joint, the prosthesis simulates the thumb carpal metacarpal joint, but due to the loss of the restrictive effect of the physiological ligament, and the rotation The center is closer to the end of the physiological rotation center, which significantly changes the kinematics and soft tissue balance of the carpus metacarpal joint of the thumb. As a non-hinge prosthesis, it requires a higher surgical implantation angle on the trapezium side articular surface. Early postoperative carpal metacarpal joint dislocations occur from time to time.

Rubis II is a metal-metal interface prosthesis of the thumb carpal metacarpal joint. Its center of rotation is closer to the physiological center of rotation, and the convex surface is located on the side of the trapezoid bone. Compared with other carpometacarpal joint prostheses, it is easier to adjust the joint angle. . However, the thumb carpal metacarpal joint prosthesis with metal-metal interface is prone to metal fatigue and metal debris particles, so the prosthesis using this interface often has a high revision rate.

Therefore, the use effect of existing prosthesis is all poor.

Therefore, it is an important technical problem to be solved by those skilled in the art to provide a 3D printed thumb carpal metacarpal joint reverse prosthesis with good use effect.

Utility model content

The purpose of the utility model is to provide a 3D printed thumb carpal metacarpal joint reverse prosthesis, so as to alleviate the technical problem of good use effect in the prior art.

In the first aspect, the embodiment of the present utility model provides a 3D printed thumb carpal metacarpal joint reverse prosthesis, including a carpal ball, a metacarpal cap and a metacarpal rod;

The bottom of the carpal ball is provided with a connection seat, and the connection seat can be connected with both the trapezium and the trapezium through a threaded connector;

The metacarpal cap is arranged on the carpal ball, and a pin is arranged between the metacarpal cap and the carpal ball;

The metacarpal rod that can be inserted into the metacarpal bone is arranged on the side of the metacarpal bone cap away from the carpal bone ball.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein, the articular surface of the above-mentioned carpal bone is provided with a cobalt-chromium-molybdenum alloy layer;

The articular surface of the metacarpal cap is coated with a layer of highly crosslinked high molecular weight polyethylene.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein the above-mentioned connecting seat is a 3D printed bone trabecular structure.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein the metacarpal rod is a 3D printed trabecular bone structure.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation of the first aspect, wherein the above-mentioned 3D printed thumb carpal metacarpal joint reverse prosthesis also includes a first metacarpal prosthesis, and the first metacarpal prosthesis The body is arranged on the side of the metacarpal cap away from the ball of the carpus;

The metacarpal rod is arranged at the end of the first metacarpal prosthesis away from the metacarpal cap.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation of the first aspect, wherein the above-mentioned connecting seat is provided with a connecting hole penetrating through the connecting seat, and the threaded connector can pass through the connecting seat. The connecting hole connects with both the trapezium and the trapezium.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein the connection hole is a threaded hole.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein the above-mentioned threaded connection member adopts a screw.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein, the above-mentioned metacarpal bone cap is provided with a first pin hole passing through it, and the carpal bone is provided with a first pin hole passing through it. Two pin holes, the pin shaft is inserted in the first pin hole and the second pin hole.

In combination with the first aspect, the embodiment of the present utility model provides a possible implementation manner of the first aspect, wherein, the outer wall of the above-mentioned metacarpal bone cap is provided with a plugging threaded hole at the first pin hole, and the plugging thread the diameter of the hole is greater than the diameter of the first pin hole;

A plugging cover is threadedly connected to the plugging threaded hole.

Beneficial effect:

The embodiment of the utility model provides a 3D printed thumb carpal metacarpal joint reverse prosthesis, including a carpal bone ball, a metacarpal bone cap and a metacarpal bone rod; The metacarpal bone and the trapezium are connected; the metacarpal cap is set on the carpal ball, and a pin shaft is set between the metacarpal cap and the carpal ball; the metacarpal rod that can be inserted into the metacarpal is set on the side of the metacarpal cap away from the carpal ball.

Specifically, during the prosthesis implantation operation, the medical staff will remove the proximal end of the first metacarpal and the articular cartilage of the trapezium. The guide wire was then threaded into the first metacarpal bone canal, a groove was chiseled along the guide wire, and a reamer was used to make a hole through the metacarpal against the guide wire to install the metacarpal rod. Afterwards, use a bone drill and a planer to plan a groove on the trapezium with the same size as the connecting seat on the ball of the carpus, and drill from the radial side of the trapezium to drill out the bone tunnel that fits the connecting seat and set the threaded connector , and then put the connecting seat of the carpal bone into the groove of the trapezium, and the threaded connecting piece passes through the trapezium bone, the carpal bone, and the trapezium bone on the other side from the radial side of the trapezium along the bone canal, and small trapezium. Afterwards, put the metacarpal stem part into the groove of the metacarpal bone canal, align the articular surface of the carpal ball with the articular surface of the metacarpal cap, and then insert the pin shaft. The shape of the articular surface at the distal end of the carpal ball simulates the physiological rotation center of the carpus metacarpal joint of the thumb, and moves the rotation center closer to the trapezium, shortening the resistance arm of the lever around the joint and increasing the power arm. Therefore, the power that can be provided to the distal end during postoperative muscle contraction is structurally increased, which is conducive to enhancing the mobility of the affected finger after surgery. Since there is no need to excavate a large amount of trapezium bone to implant a larger cap structure, the damage to the trapezium is reduced, which is beneficial to reduce the probability of periprosthetic fractures. Adjusted the actual use effect.

Description of drawings

In order to more clearly illustrate the specific implementation of the utility model or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the specific implementation or the prior art will be briefly introduced below. Obviously, the following descriptions The accompanying drawings are some implementations of the utility model, and those skilled in the art can also obtain other drawings according to these drawings without any creative work.

Fig. 1 is the schematic diagram of the first embodiment of the 3D printed thumb carpal metacarpal joint trans prosthesis provided by the embodiment of the present invention;

Fig. 2 is the explosion schematic diagram of the first embodiment of the 3D printed thumb carpal metacarpal joint trans prosthesis provided by the embodiment of the present invention;

Fig. 3 is a schematic diagram of the first embodiment of the 3D printed thumb carpal metacarpal joint trans prosthesis provided by the embodiment of the present invention when in use;

Fig. 4 is a schematic diagram of the second embodiment of the 3D printed thumb carpal metacarpal joint trans prosthesis provided by the embodiment of the present invention.

icon:

100-carpal bone ball; 110-connecting seat; 111-connecting hole; 120-threaded connector; 130-second pin hole;

200-metacarpal bone cap; 210-first pin hole

300 - metacarpal rod;

400-pin shaft;

500-first metacarpal prosthesis;

610 - trapezium; 620 - small trapezium.

Detailed ways

The technical solutions of the utility model will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the utility model, but not all of them. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial ", "radial", "circumferential" and other indicated orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, which are only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying No device or element must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, a feature defined as "first" and "second" may explicitly or implicitly include one or more of these features. In the description of the present utility model, "plurality" means two or more, unless otherwise specifically defined.

In this utility model, unless otherwise specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connection, or integration; it can be mechanical connection or electrical connection; it can be direct connection or indirect connection through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model according to specific situations.

The utility model will be described in further detail below through specific embodiments in conjunction with the accompanying drawings.

Referring to Fig. 1, Fig. 2 and Fig. 3, the embodiment of the present utility model provides a 3D printed thumb carpal metacarpal joint trans prosthesis, comprising a carpal bone ball 100, a metacarpal bone cap 200 and a metacarpal bone rod 300; the bottom of the carpal bone ball 100 A connecting seat 110 is provided, and the connecting seat 110 can be connected with both the trapezoid bone 610 and the small trapezium bone 620 through the threaded connector 120; A pin shaft 400 is arranged between them; the metacarpal rod 300 that can be inserted into the metacarpal bone is arranged on the side of the metacarpal cap 200 away from the carpal ball 100 .

Wherein, the connection base 110 is provided with a connection hole 111 penetrating through the connection base 110 , and the threaded connector 120 can pass through the connection hole 111 to connect with both the trapezium 610 and the small trapezium 620 . The connecting hole 111 is a threaded hole. The threaded connector 120 adopts a screw. The metacarpal cap 200 is provided with a first pin hole 210 passing through it, the carpal bone 100 is provided with a second pin hole 130 passing through it, and the pin shaft 400 is inserted into the first pin hole 210 and the second pin hole 130 .

Wherein, the proximal end refers to the end close to the trapezium 610 , and the distal end refers to the end away from the trapezium 610 .

Specifically, during the prosthesis implantation operation, the medical personnel will remove the proximal end of the first metacarpal and the articular cartilage of the trapezium 610 together. Then the guide wire is passed into the bone canal of the first metacarpal bone, a groove is chiseled along the direction of the guide wire, and then a hole through the metacarpal is made with a reamer by means of the guide wire to install the metacarpal rod 300 . Afterwards, use a bone drill and a planer to plan a groove on the trapezium 610 with the same size as the connection seat 110 on the carpal bone 100, and drill from the radial side of the trapezium 610 to drill out threads that fit the connection seat 110 Connecting part 120 of the bone canal, and then put the connecting seat 110 of the carpal bone 100 into the groove of the trapezium 610, and the threaded connecting part 120 passes through the bone of the trapezium 610 from the radial side of the trapezium 610 along the bone canal, Carpal ball 100 , trapezium 610 on the other side, and trapezium 620 . Afterwards, the metacarpal rod 300 is partially placed into the groove of the metacarpal bone canal, the articular surface of the carpal ball 100 and the articular surface of the metacarpal cap 200 are aligned, and then the pin 400 is inserted. The shape of the articular surface at the distal end of the carpal ball 100 simulates the physiological rotation center of the carpus metacarpal joint of the thumb, moving the rotation center closer to the trapezium 610, shortening the resistance arm of the lever around the joint and increasing the dynamic force Therefore, the power that can be provided to the distal end during postoperative muscle contraction is structurally increased, which is conducive to enhancing the mobility of the affected finger after surgery. Because there is no need to excavate a large amount of bone of the trapezium 610 to implant a larger cap-shaped structure, the damage to the trapezium 610 is reduced, so it is beneficial to reduce the probability of periprosthetic fractures. Adjusted the actual use effect.

In addition, the angle of the metacarpal bone cap 200 in the distal component is fixedly connected with the metacarpal bone rod 300, which is less prone to the problem that the angle of the articular surface deviates too much from the designed angle during the operation, and can better avoid dislocation caused by the inaccurate angle of the joint cap. enhanced stability. Moreover, the carpal bone ball 100 and the metacarpal bone cap 200 are connected by the pin shaft 400 (the pin shaft 400 is connected to form a hinged structure) to further strengthen the stability of the prosthesis. On the one hand, it is beneficial to avoid postoperative prosthesis dislocation; The thumb carpal metacarpal joint needs to withstand up to 120kg of shear force and pressure during the palm-to-palm movement. Therefore, a stable and shear-resistant joint to a certain extent plays a vital role in restoring the palm-to-palm strength of the postoperative patient. Hinged prostheses have advantages over non-hinged prostheses in providing shear stability. The metacarpal prosthesis simulates the physiological shape of the first metacarpal bone, which is beneficial to reconstruct the physiological shape of the thumb for patients with severe metacarpal bone damage. Finally, power reconstruction was performed with a tendon graft at the distal end of the thumb to restore mobility.

Referring to Fig. 1, Fig. 2 and Fig. 3, in the optional solution of this embodiment, the articular surface of the carpal bone 100 is provided with a cobalt-chromium-molybdenum alloy layer; vinyl layer. The connecting seat 110 is a 3D printed bone trabecular structure. The metacarpal rod 300 is a 3D printed bone trabecular structure.

Specifically, the connecting seat 110 adopts a 3D printed trabecular bone structure, and utilizes the excellent bone ingrowth characteristics of the trabecular bone structure and the fixing effect of screws to achieve firm biological fixation between the connecting seat 110 of the carpal bone 100 and the trapezoid bone 610 .

In addition, the joint interface of the 3D printed thumb carpal metacarpal joint trans prosthesis provided in this embodiment uses a metal-to-highly cross-linked polyethylene (MOPxl) interface, and the articular surface at the proximal end of the metacarpal cap 200 is highly cross-linked polyethylene. The surface of the ball 100 is cobalt chromium molybdenum alloy. Both highly cross-linked polyethylene and cobalt-chromium-molybdenum alloy have good biocompatibility, and the friction coefficient between them is close to that of normal human joints. This type of interface is easier to withstand impact than the "hard-to-hard" interface. Although the wear resistance of MOPxl is slightly weaker than that of metal, it avoids the possible adverse factors of metal-to-metal interface (inflammatory pseudotumor of surrounding tissue, periprosthetic bone, etc.) Necrosis, potential metal ion toxicity, local soft tissue reaction caused by metal corrosion, neck corrosion fracture and metal ion release, etc.), safety and reliability are better.

It should be pointed out that the carpal bone 100 and the matching metacarpal cap 200 have various sizes and models. According to the physique and body shape of different patients, medical staff can use prostheses of different sizes and models to treat patients.

Referring to Fig. 4, in the optional solution of this embodiment, the 3D printed thumb carpal metacarpal joint trans prosthesis also includes a first metacarpal prosthesis 500, and the first metacarpal prosthesis 500 is arranged on the side of the metacarpal cap 200 away from the carpal ball 100 One side; the metacarpal rod 300 is set at the end of the first metacarpal prosthesis 500 away from the metacarpal cap 200 .

Specifically, when the patient's first metacarpal needs to be replaced with a prosthesis, the medical staff will remove the articular cartilage at the proximal end of the proximal phalanx together with the first metacarpal. Then the guide wire is passed through the bone canal of the proximal phalanx, a groove is chiseled along the direction of the guide wire, and then a hole through the phalanx is made with a reamer against the guide wire to install the metacarpal rod 300 . The process of fixing the carpal ball 100 is consistent with the aforementioned steps. Finally, place the 3D-printed phalanx rod and metacarpal prosthesis into the groove of the phalanx bone canal so that the two articular surfaces fit together, insert the hinge shaft through the hinge hole on the joint, fix the hinge shaft, and adjust the wrist and metacarpal joint of the thumb The degree of mobility makes it suitable for activities. Finally fix the prosthesis.

In the optional solution of this embodiment, the outer wall of the metacarpal bone cap 200 is located at the first pin hole 210 and is provided with a plugging threaded hole, and the diameter of the plugging threaded hole is greater than the diameter of the first pin hole 210; With sealing cap.

Specifically, after the pin shaft 400 is inserted into the carpal bone 100 and the metacarpal cap 200 , a plugging cover is arranged at the plugging threaded hole of the metacarpal cap 200 to limit the pin shaft 400 and prevent the pin shaft 400 from moving arbitrarily.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present utility model, and are not intended to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present utility model. .

Claims (10)

1. A3D printed thumb carpometacarpal joint reverse prosthesis, comprising: a carpal ball (100), a metacarpal cap (200), and a metacarpal rod (300);

the bottom of the carpal ball (100) is provided with a connecting seat (110), and the connecting seat (110) can be connected with a trapezium (610) and a trapezium (620) through a threaded connecting piece (120);

the metacarpal cap (200) is covered on the carpal ball (100), and a pin shaft (400) is arranged between the metacarpal cap (200) and the carpal ball (100);

the metacarpal rod (300) capable of being placed in the metacarpal bone is arranged on one side, away from the carpal ball (100), of the metacarpal cap (200).

2. The 3D printed thumb carpometacarpal joint trans prosthesis of claim 1, characterized in that the articular surface of the carpal ball (100) is provided with a cobalt chromium molybdenum alloy layer;

the articular surface of the metacarpal cap (200) is coated with a highly crosslinked high molecular weight polyethylene layer.

3. The 3D printed thumb carpometacarpal joint trans prosthesis of claim 1, wherein the connection seat (110) is a 3D printed trabecular bone structure.

4. The 3D-printed thumb carpometacarpal joint trans-prosthesis according to claim 3, characterized in that the metacarpal rod (300) is a 3D-printed trabecular bone structure.

5. The 3D printed thumb carpometacarpal joint trans-prosthesis according to any of claims 1-4, further comprising a first metacarpal prosthesis (500), the first metacarpal prosthesis (500) being disposed on a side of the metacarpal cap (200) facing away from the carpal ball (100);

the metacarpal rod (300) is arranged at one end of the first metacarpal prosthesis (500) departing from the metacarpal cap (200).

6. The 3D printing thumb carpometacarpal joint trans-prosthesis according to any one of claims 1-4, characterized in that the connecting seat (110) is provided with a connecting hole (111) penetrating through the connecting seat (110), and the threaded connecting element (120) can pass through the connecting hole (111) to be connected with both the trapezium (610) and the trapezium (620).

7. The 3D printed thumb carpometacarpal joint trans-prosthesis according to claim 6, characterized in that the connection hole (111) is a threaded hole.

8. The 3D printed thumb carpometacarpal joint trans-prosthesis of claim 6, wherein the threaded connection (120) employs a screw.

9. The 3D printing thumb carpometacarpal joint trans-prosthesis according to any one of claims 1-4, characterized in that the metacarpal cap (200) is provided with a first pin hole (210) penetrating therethrough, the carpal ball (100) is provided with a second pin hole (130) penetrating therethrough, and the pin shaft (400) is inserted into the first pin hole (210) and the second pin hole (130).

10. The 3D printing thumb carpometacarpal joint trans-prosthesis of claim 9, wherein the outer wall of the metacarpal cap (200) at the first pin hole (210) is provided with a blocking threaded hole, and the diameter of the blocking threaded hole is larger than that of the first pin hole (210);

and a plugging cover is in threaded connection with the plugging threaded hole.

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