CN110840633A

CN110840633A - Finger joint implant

Info

Publication number: CN110840633A
Application number: CN201911141122.1A
Authority: CN
Inventors: 谢庆平; 陆芸
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-20
Filing date: 2019-11-20
Publication date: 2020-02-28

Abstract

The invention discloses a finger joint implant, comprising: the invention utilizes the insertion and pull type connecting structure of the prosthesis and the joint platform to accurately control the position and the angle of the prosthesis in a medullary cavity of a phalange, and the hollow short column can be transversely deformed and expanded to clamp the inner wall of the medullary cavity when being screwed in, thereby improving the intramedullary fastening force of the prosthesis and maintaining the long-term fixed stability and reliability of the prosthesis in the medullary cavity.

Description

Finger joint implant

Technical Field

The invention relates to the field of medical instruments, in particular to a finger joint implant which is convenient to implant, firm to install, not easy to dislocate and more suitable for a physiological activity mode.

Background

The function of the natural joint is completely lost or partially lost due to surface abrasion or injury or damage, an artificial joint is required to be implanted to replace the function defect of the joint, the existing artificial joint replacement has more common application, and brings hope to patients with joint diseases, the existing artificial joint implantation generally adopts the method that a prosthesis connected with a joint head part or a socket part is directly inserted into a bone marrow cavity and is fixed through a screw or a nut to bear the corresponding joint head part or the joint socket part, because the joint needs to bear larger torque and mass in the displacement/torsion process, higher requirements are provided for the firmness and reliability of the prosthesis installation, therefore, the common screw threads are adopted for fastening, the phenomena of loosening, over-stretching, over-bending and the like can be generated in the long-term use process, the normal use of the artificial joint is seriously influenced, and the function of the artificial joint is even lost, not only brings pain to the patient, but also increases the treatment cost of the patient.

Disclosure of Invention

The invention mainly solves the technical problems that the connection is loosened and the joint function is influenced; provides the finger joint implant which is convenient to implant, firm to install, not easy to dislocate and more accordant with the physiological activity mode.

In order to solve the technical problems, the invention mainly adopts the following technical scheme:

the finger joint implant of the present invention is used for replacement of an interphalangeal joint, and includes:

the joint platform comprises a joint head and a joint socket which are matched with each other, wherein the joint head and the joint socket form an inlaid concave-convex curved surface structure and can rotate and/or displace mutually to form a central shaft curve movable connection;

the distal prosthesis is used for connecting the distal phalanx and the joint platform and comprises an integrated front section short column and a rear section threaded column;

a proximal prosthesis having the same structure as the distal prosthesis for coupling the proximal phalanx and the articular platform;

the movable connection mode of the upper proximal prosthesis and the joint platform is utilized to accurately position the position and the angle of the prosthesis in the medullary cavity of the phalanx, and the inlaid curved surface design of the joint head and the joint socket has the curved surface motion characteristic of a human joint, can generate smooth curved surface motion, accords with the biomechanics, prevents over-extension and over-flexion and reduces dislocation.

Preferably, the short column is a hollow tubular structure, the head of the short column is in a semicircular shape or an arc shape or a conical top shape, a plurality of longitudinal slots which extend along the axis of the short column and are parallel to each other are annularly distributed on the surface of the short column, a plurality of slots form an elastic deformation structure of the wall surface of the short column, the wall surface of the hollow short column is designed into a multi-sheet elastic deformation structure, the length can be compressed when the front end is blocked in the screwing-in process, the short column is transversely elastically deformed and expanded and blocks the wall surface of a medullary cavity of a phalanx so as to improve the intramedullary fastening force of the prosthesis, and meanwhile, the hollow inner cavity structure with the longitudinal slots is also beneficial to the immersion and the growth of bone tissues.

Preferably, the wall surface of the short column is provided with a plurality of transverse ring grooves distributed along the axial line of the short column, the cross sections of the ring grooves are arc-shaped, square, rectangular or trapezoidal, and the transverse ring grooves on the wall surface of the short column can improve the elastic deformability of the wall surface of the short column, facilitate the immersion and growth of bone tissues and maintain the long-term fixation stability and reliability of the prosthesis in marrow.

Preferably, the threaded column is provided with tapered threads, and the surface of the threaded column is provided with a plurality of longitudinal grooves annularly distributed along the central axis of the threaded column. The taper thread is convenient for screwing the thread, can generate stronger holding force, is not easy to loosen, effectively relieves the back contusion force caused by joint rotation, and the longitudinal slotting is favorable for the immersion and growth of bone tissues, and maintains the stability and reliability of the long-term fixation of the prosthesis on the phalanges.

Preferably, the ratio of the pitch diameter of the tapered thread to the width of the longitudinal groove is 1: 0.15-0.25, and the proper groove width can ensure that the prosthesis is screwed in and can effectively promote the immersion and growth of bone tissues.

Preferably, be equipped with the cylinder coaxial with screw thread post axis on the screw thread post rear end face, be equipped with an at least recess on the cylinder, the embedded solid fixed ring that is equipped with of recess, the outer terminal surface of joint head and the outer terminal surface central authorities of joint nest all are equipped with the mounting hole, the mounting hole is the round hole form, and the round hole is identical with above-mentioned cylinder and holds the cylinder, is equipped with the draw-in groove identical with above-mentioned recess on the round hole internal face, and above-mentioned cylinder inlays to locate in the round hole and through the solid fixed ring joint in the round hole of elasticity, and the connection of false body and joint platform adopts the formula structure of dialling of inserting, utilizes the joint effect of solid fixed ring of elasticity, makes the assembly of false body and joint head and joint nest very convenient, is favorable to the.

Preferably, a square column is further arranged between the rear end face of the cylindrical column and the rear end face of the threaded column, the side length of the square column is larger than the diameter of the cylindrical column, the cylindrical column is located in the center of the square column, the mounting holes in the joint head and the joint socket are in two sections, the joint head and the mounting holes in the joint socket comprise an upper section square hole and a lower section round hole, the square hole is matched with the square column and used for accommodating the square column, the lower section round hole is matched with the cylindrical column and used for accommodating the cylindrical column, the plug-pull type structure adopts a two-section connecting structure, the anti-rotation capacity and the angle adjustment precision of the prosthesis can be improved through the upper section square column connecting structure, and the cylindrical connecting structure is matched with an elastic fixing ring.

Preferably, the materials of the distal prosthesis, the proximal prosthesis and the joint platform are titanium alloy or cobalt-chromium alloy or ultrahigh molecular polyethylene.

The invention has the beneficial effects that: the movable connection mode of the far prosthesis, the near prosthesis and the joint platform is utilized, the position and the angle of the prosthesis in a medullary cavity of a phalanx can be accurately positioned, the inlaid curved surface design of a joint head and a joint socket has the curved surface motion characteristic of a human joint, smooth curved surface motion can be generated, the biomechanics is met, overextension and overexplexion are prevented, and dislocation is reduced.

Drawings

FIG. 1 is a schematic diagram of an embodiment of the present invention.

Fig. 2 is an exploded schematic view of the structure of fig. 1.

Fig. 3 is a schematic cross-sectional view of the joint head in the configuration of fig. 1.

Fig. 4 is a schematic cross-sectional view of the distal prosthesis in the configuration of fig. 1.

In the figure, 1, a joint platform, 11, a joint head, 111, a round hole, 112, a clamping groove, 113, a square hole, 12, a joint socket, 2, a distal prosthesis, 21, a short column, 211, a longitudinal strip seam, 212, a transverse annular groove, 22, a threaded column, 221, a longitudinal groove, 23, a cylinder, 231, a groove, 24, a square column, 3, a proximal prosthesis and 4, an elastic fixing ring.

Detailed Description

The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings.

Example (b): the finger joint implant of the present embodiment is used for replacement of an interphalangeal joint, and as shown in fig. 1 and 2, the finger joint implant includes:

the joint platform 1 comprises a joint head 11 and a joint socket 12 which are made of titanium alloy and matched with each other, wherein the joint head and the joint socket form an inlaid concave-convex curved surface structure and can rotate and/or shift mutually to form a central shaft curve movable connection, as shown in fig. 3, mounting holes are respectively designed in the centers of the outer end surfaces of the joint head and the joint socket, the mounting holes are in two sections and comprise an upper section square hole 113 and a lower section round hole 111, and the wall surface of the round hole is provided with an annular clamping groove 112;

the distal prosthesis 2 is made of titanium alloy and is used for connecting a distal phalanx and a joint platform, and comprises an integrated front section short column 21 and a rear section threaded column 22;

the proximal prosthesis has the same structure and material as the distal prosthesis and is used for connecting the proximal phalanx and the joint platform;

as shown in fig. 4, the short column is a hollow tubular structure, the head of the short column is semicircular, the length of the short column is matched with the medullary cavity of the phalanx, the outer wall surface of the short column is designed with a plurality of transverse annular grooves 212 which are distributed along the axis of the short column and are parallel to each other and three longitudinal slots 211 which extend along the axis of the short column and are uniformly distributed, the cross section of each transverse annular groove is trapezoidal, the four longitudinal slots divide the wall surface of the short column into four-leaf separation structures which are connected end to end, the threaded column is designed with tapered threads, the surface of the threaded column is provided with a plurality of longitudinal slots 221 which are distributed along the axis of the threaded column and divide the tapered threads, and the ratio of the slot width of each longitudinal: 1, screw thread post rear end face central authorities have designed in proper order and have with screw thread post body structure and with the coaxial square column 24 and the cylinder 23 of screw thread post axis, wherein the square column length of side is greater than the cylinder diameter, the square column is identical with the square hole of above-mentioned mounting hole upper segment, the cylinder is identical with the round hole of above-mentioned mounting hole hypomere, cylinder and square column insert corresponding round hole and square downthehole in proper order, a recess 231 has been designed on the cylinder, the recess corresponds the round hole draw-in groove in the above-mentioned mounting hole, the embedded solid fixed ring 4 that is equipped with of recess.

When in use, the hole is punched and the marrow is expanded at the small head of the near-end phalange, then the short column of the near-end prosthesis is inserted into the hole and enters the medullary cavity of the phalange, the conical thread of the threaded column of the near-end prosthesis is slowly screwed into the small head of the phalange and is fastened on the small head of the phalange by rotating, meanwhile, as the short column is continuously penetrated and pressed against the bottom of the near-end phalange, the hollow short column is elastically deformed and compressed, the short column is transversely expanded to tightly clamp the wall of the medullary cavity of the phalange, so as to improve the fastening force of the short column in the medullary cavity of the phalange, the hole is punched and the marrow is expanded at the bottom of the far-end phalange, the far-end prosthesis is installed and fastened, finally, the corresponding angles of the far-end prosthesis and the near-end prosthesis are adjusted, the installation hole of the joint head is nested in the two-section columnar structure at the bottom of the far-end prosthesis, when the, satisfy the assembly of dialling of inserting of distal prosthesis and joint head, and the square column inserts in the square hole, has restricted the rotation of prosthesis, has guaranteed the accuracy of distal prosthesis angular positioning, and in the same way, with the two segmentation column structures of the mounting hole nestification proximal prosthesis bottom surface of joint nest and through the solid fixed ring joint of elasticity, accomplish the assembly of dialling of proximal prosthesis and joint nest, in view of the above, can be convenient the completion finger joint implant put into.

After the fixing device is placed in the phalangeal pulp cavity, bone tissues in the phalangeal pulp cavity are immersed into the hollow cavity of the short column through the slots on the wall surface of the short column and grow and fixed, the stability and reliability of long-term fixation of the short column in the phalangeal pulp cavity are improved and maintained, the grooves in the threaded column reduce local extrusion force of the threaded column to the phalanges in the screwing-in process, the fracture and damage of the phalangeal heads or the bone bottoms are prevented, meanwhile, the bone tissues can also be immersed into and grow through the grooves, and the long-term fixation stability and reliability of the threaded column on the phalangeal heads or the bone bottoms are improved and maintained.

In the description of the present invention, the terms "upper", "lower", "front", "rear", "left", "right", "longitudinal", "lateral", "inner", "outer", etc. indicate the direction or positional relationship based on the directions or positional relationships shown in the drawings, which are only for convenience of description and understanding of the technical solutions of the present invention, and the above description is not intended to limit the present invention, and the present invention is not limited to the examples described above, and changes, modifications, additions or substitutions made by those skilled in the art within the spirit and scope of the present invention should be considered as the protection scope of the present invention.

Claims

1. A finger joint implant for replacement of an interphalangeal joint, the finger joint implant comprising:

the joint platform (1) comprises a joint head (11) and a joint socket (12) which are matched with each other, wherein the joint head and the joint socket form a mosaic concave-convex curved surface structure and can rotate and/or displace mutually to form a curve movable connection of a central shaft;

the distal prosthesis (2) is used for connecting the distal phalanx and the joint platform and comprises an anterior short column (21) and a posterior threaded column (22) which are of an integral structure;

a proximal prosthesis (3), having the same structure as the distal prosthesis, for coupling the proximal phalanx and the joint platform.

2. The finger joint implant of claim 1, wherein: the short column (21) is of a hollow tubular structure, the head of the short column is in a semicircular shape or an arc shape or a conical top shape, a plurality of longitudinal grooves (211) which extend along the axis of the short column and are parallel to each other are annularly distributed on the wall surface of the short column, and the plurality of grooves form an elastic deformation structure of the wall surface of the short column.

3. The finger joint implant of claim 2, wherein: the outer wall of the short column is provided with a plurality of transverse ring grooves (212) distributed along the axis of the short column, and the cross sections of the ring grooves are arc-shaped or square-shaped or rectangular or trapezoidal.

4. The finger joint implant according to claim 1, 2 or 3, wherein: the threaded column (22) is provided with tapered threads and a plurality of longitudinal grooves (221) which are annularly distributed along the central axis of the threaded column.

5. The finger joint implant of claim 4, wherein: the ratio of the pitch diameter of the tapered thread to the width of the longitudinal groove (221) is 1: 0.15 to 0.25.

6. The finger joint implant of claim 1, wherein: be equipped with on screw thread post (22) the rear end face with coaxial cylinder (23) of screw thread post axis, be equipped with at least one recess (231) on the cylinder, the embedded solid fixed ring of elasticity (4) that is equipped with of recess, the outer terminal surface of joint head and the outer terminal surface central authorities of joint nest all are equipped with the mounting hole, the mounting hole is round hole (111), and the round hole is identical with above-mentioned cylinder and holds the cylinder, is equipped with on the round hole internal face with the identical draw-in groove of above-mentioned recess (112), and above-mentioned cylinder inlays to locate in the round hole and through solid fixed ring joint.

7. The finger joint implant of claim 6, wherein: the square column (24) is further arranged between the rear end faces of the cylinder (23) and the threaded column (22), the side length of the square column is larger than the diameter of the cylinder, the cylinder is located in the center of the square column, the mounting hole is of two sections and comprises an upper section square hole (113) and a lower section round hole (111), the square hole is matched with the square column and used for accommodating the square column, and the round hole is matched with the cylinder and used for accommodating the cylinder.

8. The finger joint implant of claim 1, wherein: the joint platform (1), the distal prosthesis (2) and the proximal prosthesis (3) are made of titanium alloy or cobalt-chromium alloy or ultrahigh molecular polyethylene.