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 printing thumb carpometacarpal joint trans-prosthesis

Technical Field

The utility model relates to the technical field of medical equipment, particularly, relate to 3D prints thumb carpometacarpal joint trans-form false body.

Background

The Thumb carpometacarpal joint (CMC 1) can perform flexion, extension, adduction, abduction, rotation, and other movements, and is the joint with the greatest movement of the hand. In daily life, the thumb carpometacarpal joint is often subjected to a large pressure when being held under the action of a special saddle-shaped joint surface and a dorsal ligament thereof. The diseases requiring implantation of the thumb carpometacarpal joint prosthesis are: 1. non-inflammatory degenerative joint diseases of the carpometacarpal joint, including osteoarthritis, post-traumatic arthritis, and the like. 2. Rheumatoid arthritis. 3. Other approaches treat patients who fail.

For these diseases, there are several clinical surgical approaches, such as: the method comprises the following steps of arthroscopic glide membrane resection, arthroscopic trapezium resection and ligament reconstruction, first metacarpal basal wedge osteotomy, simple trapezium resection or tendon group filling, carpometacarpal joint fusion, prosthesis replacement or intergraft filling and the like.

The thumb carpometacarpal joint prosthesis has various forms and various types. For the total thumb carpometacarpal joint replacement prosthesis, foreign patents of the total thumb carpometacarpal joint prosthesis such as metal-metal interface prosthesis like Elektra and Motec, metal-high polymer interface prosthesis like Arpe and Moovis, ceramic prosthesis like Moje Acamo and the like exist, wherein Rubis II is a reverse first metacarpophalangeal joint prosthesis with a metal-metal interface. The prostheses are implanted into the trapezium bone through screws or spiral emboli and then into the metacarpal bone through a metacarpal rod, so that the aims of keeping and improving the mobility of the metacarpal joint of the thumb and the palm and relieving pain are fulfilled.

The Elektra, arc and other prostheses use metal-highly crosslinked polyethylene or metal-metal interfaces, compared with a normal thumb carpometacarpal joint, the prosthesis simulates the thumb carpometacarpal joint, but the kinematics and the soft tissue balance of the thumb carpometacarpal joint are obviously changed because the limit function of physiological ligaments is lost and the rotation center is closer to the near end than the physiological rotation center, and as a non-hinge prosthesis, the prosthesis has higher requirement on the surgical implantation angle of a trapezium side joint surface and is generated when the carpometacarpal joint is dislocated in the early post-operation period.

Rubis II, as a metal-metal interface trans-thumb carpometacarpal joint prosthesis, has a center of rotation closer to the physiological center of rotation and a convex surface on the trapezium side, making it easier to adjust the joint angle compared to the rest of carpometacarpal joint prostheses. However, the thumb carpometacarpal joint prosthesis with the metal-metal interface has the problem of high repair rate due to the fact that metal fatigue and metal debris particles are easy to generate.

Therefore, the existing prosthesis has poor using effect.

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

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a 3D prints thumb carpometacarpal joint trans-form false body to alleviate the technical problem that excellent in use effect among the prior art.

In a first aspect, an embodiment of the utility model provides a 3D-printed thumb carpometacarpal joint trans-prosthesis, which 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 trapezoid bone 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 rod which can be placed in the metacarpal bone is arranged on one side of the metacarpal cap, which is far away from the carpal ball.

With reference to the first aspect, embodiments of the present invention provide a possible implementation manner of the first aspect, wherein a cobalt-chromium-molybdenum alloy layer is disposed on a joint surface of the carpal ball;

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

In combination with the first aspect, an embodiment of the present invention provides a possible implementation manner of the first aspect, wherein the connecting seat is a 3D printed bone trabecular structure.

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

With reference to the first aspect, an embodiment of the present invention provides a possible implementation manner of the first aspect, wherein the 3D printed reverse thumb carpometacarpal joint prosthesis further includes a first metacarpal prosthesis, and the first metacarpal prosthesis is disposed on a side of the metacarpal cap facing away from the carpal ball;

the metacarpal rod is arranged at one end of the first metacarpal prosthesis, which deviates from the metacarpal cap.

In combination with the first aspect, an embodiment of the present invention provides a possible implementation manner of the first aspect, wherein a connection hole penetrating through the connection seat is provided on the connection seat, and the threaded connection member can pass through the connection hole to be connected with both the trapezium bone and the trapezoid bone.

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

In combination with the first aspect, embodiments of the present invention provide a possible implementation manner of the first aspect, wherein the threaded connector is a screw.

In combination with the first aspect, an embodiment of the present invention provides a possible implementation manner of the first aspect, wherein a first pin hole penetrating through the metacarpal cap is provided on the metacarpal cap, a second pin hole penetrating through the carpal ball is provided on the carpal ball, and the pin shaft is inserted into the first pin hole and the second pin hole.

With reference to the first aspect, an embodiment of the present invention provides a possible implementation manner of the first aspect, wherein a plugging threaded hole is formed in the outer wall of the metacarpal cap at the first pin hole, and a diameter of the plugging threaded hole is larger than a diameter of the first pin hole;

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

Has the beneficial effects that:

the embodiment of the utility model provides a 3D printing thumb carpometacarpal joint reverse prosthesis, which 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.

Specifically, in the prosthesis implantation operation, the medical staff will remove the articular cartilage of the proximal end of the first metacarpal bone and the trapezium bone together. A guide wire is then passed through the first metacarpal canal, a groove is drilled in the direction of the guide wire, and a reamer is then used against the guide wire to make a hole through the metacarpal to install the metacarpal rod. Then, a groove with the same size as the connecting seat on the carpal ball is planed on the trapezium by using a bone drill and a planer tool, the drill is inserted into the groove from the radial side of the trapezium to drill a bone passage which is in accordance with the connecting seat and is provided with a threaded connecting piece, then the connecting seat of the carpal ball is placed into the groove of the trapezium, and the threaded connecting piece sequentially penetrates through the trapezium bone, the carpal ball, the trapezium bone on the other side and the trapezium bone from the radial side of the trapezium along the bone passage. Then, the metacarpal bone part is placed into the groove of the metacarpal bone canal, the joint surface of the carpal ball and the joint surface of the metacarpal cap are jointed, and then the pin shaft is inserted. The joint surface form of the far end of the carpal ball simulates the physiological rotation center of the metacarpal joint of the thumb, the rotation center which is closer to the trapezium is moved far, the resistance force arm of the lever around the joint is shortened, and the power force arm is increased, so that the power which can be provided for the far end when the muscle contracts after operation is structurally amplified, and the movement capability of the affected fingers after operation is favorably enhanced. Because a large amount of bone of the trapezium does not need to be dug to implant a large cap-shaped structure, the damage to the trapezium is reduced, and the probability of fracture around the prosthesis is favorably reduced. The actual use effect is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments or the technical solutions in the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic view of a first implementation of a 3D printed reverse thumb carpometacarpal joint prosthesis provided by an embodiment of the present invention;

fig. 2 is an exploded schematic view of a first embodiment of a 3D printed reverse prosthesis for a metacarpal joint of a thumb provided in an embodiment of the present invention;

fig. 3 is a schematic view of a 3D printed reverse thumb carpometacarpal joint prosthesis according to an embodiment of the present invention in use;

fig. 4 is a schematic diagram of a 3D printing of a second implementation manner of a reverse prosthesis of a metacarpal joint of a thumb provided by an embodiment of the present invention.

Icon:

100-carpal ball; 110-a connecting seat; 111-connection hole; 120-a threaded connection; 130-a second pin hole;

200-metacarpal cap; 210-first pinhole

300-metacarpal bone rods;

400-pin shaft;

500-a first metacarpal prosthesis;

610-trapezium bone; 620-polygonal bone.

Detailed Description

The technical solutions of the present invention will be described more clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

The present invention will be described in further detail below with reference to specific embodiments and with reference to the attached drawings.

Referring to fig. 1, 2 and 3, an embodiment of the present invention provides a 3D printed thumb carpometacarpal joint transprosthesis, which includes 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 both the trapezium 610 and the trapezium 620 through a threaded connector 120; the metacarpal cap 200 covers the carpal ball 100, and a pin shaft 400 is arranged between the metacarpal cap 200 and the carpal ball 100; a metacarpal rod 300, which can be placed in the metacarpal bone, is provided on the side of the metacarpal cap 200 facing away from the carpal ball 100.

Wherein, the connecting base 110 is provided with a connecting hole 111 penetrating through the connecting base 110, and the threaded connecting member 120 can penetrate through the connecting hole 111 to be connected with the trapezium 610 and the trapezium 620. The attachment hole 111 is a threaded hole. The threaded connection 120 is a screw. 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 400 is inserted into the first pin hole 210 and the second pin hole 130.

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

Specifically, during the prosthesis implantation procedure, the medical staff will remove the articular cartilage of the proximal end of the first metacarpal bone and the trapezium bone 610 together. A guide wire is then passed through the first metacarpal canal, a groove is drilled in the direction of the guide wire, and a reamer is then used against the guide wire to make a hole through the metacarpal to install the metacarpal rod 300. Then, a groove with the same size as the connecting seat 110 of the wrist ball 100 is planed on the trapezium 610 by using a bone drill and a planer tool, a drill is inserted from the radial side of the trapezium 610 to drill a bone passage which is matched with the connecting seat 110 and is provided with the threaded connecting piece 120, then the connecting seat 110 of the wrist ball 100 is inserted into the groove of the trapezium 610, and the threaded connecting piece 120 sequentially penetrates through the bone of the trapezium 610, the wrist ball 100, the bone of the trapezium 610 on the other side and the trapezium 620 from the radial side of the trapezium 610 along the bone passage. Then, the metacarpal rod 300 is partially placed in the groove of the metacarpal canal, the joint surface of the carpal ball 100 and the joint surface of the metacarpal cap 200 are aligned, and then the pin 400 is inserted. The shape of the joint surface at the far end of the carpal ball 100 simulates the physiological rotation center of the metacarpal joint of the thumb, the rotation center which is closer to the trapezium 610 is moved far, the resistance force arm of the lever around the joint is shortened, and the power force arm is increased, so that the power which can be provided for the far end when the muscle contracts after operation is structurally increased, and the movement capability of the affected finger after operation is favorably enhanced. Since it is not necessary to dig out a large amount of bone of the trapezium 610 to implant a large cap-like structure, the damage to the trapezium 610 is reduced, thus contributing to a reduction in the probability of periprosthetic fractures. The actual use effect is improved.

In addition, the angle of the metacarpal cap 200 in the distal end assembly is fixedly connected with the metacarpal rod 300, so that the problem that the angle of the joint surface deviates too much from the design angle in the operation is not easy to occur, dislocation caused by inaccurate angle of the joint cap can be better avoided, and the stability is structurally enhanced. Moreover, the carpal ball 100 and the metacarpal cap 200 are connected through the pin 400 (the pin 400 is connected to form a hinge structure), so that the stability of the prosthesis is further enhanced, on one hand, the dislocation of the prosthesis after the operation is avoided, on the other hand, as the thumb carpometacarpal joint needs to bear the shearing force and the pressure up to 120kg when the palm acts, a stable and certain shearing force resistant joint plays a crucial role in recovering the palm strength of a patient after the operation, and the hinge type prosthesis has the advantage that the non-hinge type prosthesis cannot be replaced in the aspect of providing the shearing resistance stability. The metacarpal prosthesis simulates the physiological shape of the first metacarpal and is beneficial to reconstructing the physiological shape of the thumb for patients with serious metacarpal destruction. Finally, the power is rebuilt through the tendon transplantation at the far end of the thumb, so as to achieve the effect of restoring the activity.

Referring to fig. 1, 2 and 3, in an alternative embodiment, 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. The connecting socket 110 is a 3D printed trabecular bone structure. Metacarpal rod 300 is a 3D printed trabecular bone structure.

Specifically, the connecting seat 110 adopts a 3D printed trabecular bone structure, and the excellent bone ingrowth characteristic of the trabecular bone structure and the fixation effect of screws are utilized to achieve the firm biological fixation of the connecting seat 110 of the carpal ball 100 and the trapezium 610.

In addition, the joint interface of the 3D printed reverse prosthesis of the metacarpal joint of the thumb provided in this embodiment applies a metal-to-highly cross-linked polyethylene (MOPxl) interface, the joint surface of the proximal end of the metacarpal cap 200 is made of highly cross-linked polyethylene, and the surface of the carpal ball 100 is made of cobalt-chromium-molybdenum alloy. The high cross-linked polyethylene and the cobalt-chromium-molybdenum alloy have good biocompatibility, and the friction coefficient between the high cross-linked polyethylene and the cobalt-chromium-molybdenum alloy is close to the friction coefficient of a normal joint of a human body. The interface is more resistant to impact than a hard-to-hard interface, and the wear resistance of MOPxl is slightly weaker than that of metal, so that the possible adverse factors (inflammatory pseudotumor of surrounding tissues, osteonecrosis around prosthesis, potential metal ion toxicity, local soft tissue reaction caused by metal corrosion, neck corrosion fracture, metal ion release and the like) generated by the metal-to-metal interface are avoided, and the safety and the reliability are better.

It should be noted that the carpal ball 100 and associated metacarpal cap 200 may be of various sizes and types, and medical personnel may use prostheses of different sizes and types to treat patients depending on their physique and size.

Referring to fig. 4, in an alternative of this embodiment, the 3D printed thumb carpometacarpal joint transprosthesis further comprises 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; metacarpal stem 300 is disposed at an end of first metacarpal prosthesis 500 facing away from metacarpal cap 200.

Specifically, when the prosthesis needs to be replaced in the first metacarpal bone of the patient, the medical staff can cut off the articular cartilage near the proximal end of the phalanx and the first metacarpal bone. The guide wire is then passed into the proximal phalanx canal, a groove is chiseled in the direction of the guide wire, and a reamer is then used against the guide wire to make a hole through the phalanx to install the metacarpal rod 300. The process of securing the carpal ball 100 is consistent with the steps previously described. And finally, placing the 3D printed phalanx rod and the metacarpal bone prosthesis component into the groove of the phalanx bone pipe, enabling the joint surfaces of the phalanx rod and the metacarpal bone prosthesis component to be closed, inserting the hinge shaft through the hinge hole in the joint, fixing the hinge shaft, and adjusting the mobility of the joint of the thumb, the wrist and the palm to enable the joint to be suitable for movement. And finally fixing the prosthesis.

In an alternative of this embodiment, a plugging threaded hole is formed in the outer wall of the metacarpal cap 200 at the first pin hole 210, and the diameter of the plugging threaded hole is larger than that of the first pin hole 210; the plugging threaded hole is in threaded connection with a plugging cover.

Specifically, after the pin 400 is inserted into the carpal ball 100 and the metacarpal cap 200, the blocking cover is arranged at the blocking threaded hole of the metacarpal cap 200 to limit the pin 400, and the pin 400 is prevented from moving randomly.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the embodiments of the present invention.

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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