CN114259287A

CN114259287A - Intramedullary locking pin assembly

Info

Publication number: CN114259287A
Application number: CN202111603651.6A
Authority: CN
Inventors: 袁博文; 李健; 廖棋宾; 赵梦楠
Original assignee: Beijing Libeier Bio Engineering Institute Co Ltd
Current assignee: Beijing Libeier Bio Engineering Institute Co Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2022-04-01

Abstract

The invention provides an intramedullary nail assembly, comprising: a first locking nail; the second locking nail is arranged at the first end of the first locking nail in a penetrating way, and the axis of the second locking nail is obliquely arranged relative to the axis of the first locking nail; the third locking nail is worn to establish in the middle part of first locking nail, and the axis of third locking nail sets up for the axis slope of first locking nail, and second locking nail is supported to the third locking nail, and wherein, second locking nail includes the screw thread section, and third locking nail supports the screw thread section, and the screw thread section includes body of rod portion and the screw tooth of setting in body of rod portion, is provided with a plurality of first grooves on the screw tooth. The technical scheme of this application has solved the intramedullary nail among the relevant art effectively and has worn out the problem to the thighbone outside.

Description

Intramedullary locking pin assembly

Technical Field

The invention relates to the field of medical instruments, in particular to an intramedullary lock pin assembly.

Background

For femoral intertrochanteric fracture, femoral intramedullary nails are generally adopted for fixation, and at present, a lever-like structure is formed after an intramedullary nail operation. The stability of the lever-like structure formed by the internal intramedullary nail is obviously inferior to that of the triangular support structure formed by normal bone tissues. Because the intramedullary nail belongs to a rigid structure and is made of metal materials, the intramedullary nail system is easy to generate stress shielding in the compression process due to overhigh elasticity modulus of the femoral system, thereby easily causing internal fixation failure or the condition that the intramedullary nail penetrates out of the femur and the like.

Disclosure of Invention

The invention mainly aims to provide an intramedullary locking nail assembly to solve the problem that intramedullary nails in the related art penetrate out of femurs.

To achieve the above object, the present invention provides an intramedullary nail assembly comprising: a first locking nail; the second locking nail is arranged at the first end of the first locking nail in a penetrating way, and the axis of the second locking nail is obliquely arranged relative to the axis of the first locking nail; the third locking nail is worn to establish in the middle part of first locking nail, and the axis of third locking nail sets up for the axis slope of first locking nail, and second locking nail is supported to the third locking nail, and wherein, second locking nail includes the screw thread section, and third locking nail supports the screw thread section, and the screw thread section includes body of rod portion and the screw tooth of setting in body of rod portion, is provided with a plurality of first grooves on the screw tooth.

Further, a plurality of first grooves located on the same circle of threads are radially arranged.

Further, the height of the screw teeth of the screw thread section is gradually reduced from a direction away from the first locking nail to a direction close to the first locking nail.

Further, the rod body part comprises a first rod body part and a second rod body part, the first rod body part is of a polished rod structure, and a plurality of second grooves are formed in the part, located between two adjacent threads, of the second rod body part.

Furthermore, the axial dimension of the first rod body part is larger than that of the second rod body part, a first stop groove is formed in the first rod body part, a second stop groove communicated with the first stop groove is formed in the second rod body part, and the end part of the third locking nail is located in the first stop groove and the second stop groove.

Further, the end of the third locking nail has a flexible portion; and/or the thread section is provided with a first flexible layer.

Furthermore, the middle part of the first locking nail is provided with a first inclined hole for the third locking nail to pass through, the third locking nail comprises a first external thread section, and an internal thread in conical fit with the first external thread section is arranged on the first inclined hole.

Furthermore, a second axial through hole is formed in the first locking nail, the first inclined hole is communicated with the second axial through hole, the second axial through hole separates the first inclined hole to form a first hole section and a second hole section, the third locking nail further comprises a first polished rod section and a second polished rod section which are positioned at two ends of the first external thread section, the diameter of the second polished rod section is larger than that of the first polished rod section, the first polished rod section penetrates through the first hole section, and the internal thread is arranged on the second hole section; the third locking pin further includes a second external thread section supporting the second locking pin, the first polished rod section being located between the second external thread section and the first external thread section.

Furthermore, a second inclined hole for the second locking nail to penetrate through is formed in the first end of the first locking nail, an included angle between the axis of the second inclined hole and the axis of the first locking nail is larger than an included angle between the axis of the first inclined hole and the axis of the first locking nail, and a second flexible layer is arranged between the second locking nail and the second inclined hole.

Furthermore, the second inclined hole is a stepped hole, the second locking nail further comprises a third polished rod section connected with the threaded section, and the third polished rod section penetrates through the second inclined hole and is provided with a stepped section matched with the second inclined hole; an operation groove is formed in one end, far away from the threaded section, of the third polished rod section; an operation hole is formed in one end, far away from the first external thread section, of the third locking nail; the first locking nail comprises a fourth polished rod section and a fifth polished rod section connected with the fourth polished rod section, the outer diameter of the fourth polished rod section is larger than that of the fifth polished rod section, the third polished rod section is arranged at the first end of the fourth polished rod section in a penetrating mode, and one end, provided with the operating hole, of the third locking nail is located on one side of the second end of the fourth polished rod section; the intramedullary locking nail assembly further comprises a transverse nail which is arranged on the fifth polished rod section in a penetrating mode.

By applying the technical scheme of the invention, the intramedullary lock pin component comprises: a first locking nail, a second locking nail and a third locking nail. The second locking nail is arranged at the first end of the first locking nail in a penetrating mode, and the axis of the second locking nail is arranged obliquely relative to the axis of the first locking nail. The third locking nail penetrates through the middle of the first locking nail, the axis of the third locking nail is obliquely arranged relative to the axis of the first locking nail, and the third locking nail supports the second locking nail, so that a triangular area is defined among the first locking nail, the second locking nail and the third locking nail. Wherein the second locking pin comprises a threaded section and the third locking pin supports the threaded section. The screw thread section comprises a rod body part and screw threads arranged on the rod body part, and a plurality of first grooves are formed in the screw threads. The intramedullary lock pin component is implanted into a femur, a first lock pin is driven into the intramedullary lock pin component, a second lock pin penetrates through the first end of the first lock pin, the fracture end is pressurized through the second lock pin, a third lock pin penetrates through the middle of the first lock pin, and the third lock pin supports the second lock pin. After the intramedullary locking nail component is implanted, the intramedullary locking nail component integrally bears pressure. When the second locking nail is stressed, the thread section of the second locking nail compresses bone in the femur when being screwed in, the screw teeth provided with the first grooves enable the screw teeth to have elasticity, micro deformation can be generated, the elastic modulus of the intramedullary locking nail component is reduced, the screw teeth can be self-adaptive to the bone around the screw teeth, so that the bone around the screw teeth is inserted into the first grooves to be occluded and locked, stress shielding is reduced, and further cutting of the bone and penetration of the second locking nail out of the femur can be effectively prevented. Therefore, the technical scheme of the application can solve the problem that the intramedullary nail in the related art penetrates out of the femur.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 shows a perspective, schematic view of an intramedullary nail assembly implanted in a femur, in accordance with an embodiment of the intramedullary nail assembly of the present invention;

FIG. 2 illustrates a schematic front view of the intramedullary nail assembly of FIG. 1;

FIG. 3 illustrates a perspective view of the intramedullary nail assembly of FIG. 1;

FIG. 4 illustrates a cross-sectional schematic view of the intramedullary nail assembly of FIG. 3;

FIG. 5 shows an enlarged schematic view at A of the intramedullary nail assembly of FIG. 4;

FIG. 6 shows an enlarged schematic view at B of the intramedullary nail assembly of FIG. 4;

FIG. 7 illustrates an enlarged schematic view at C of the intramedullary nail assembly of FIG. 4;

FIG. 8 illustrates a perspective view of a second locking nail of the intramedullary nail assembly of FIG. 1;

FIG. 9 shows a front schematic view of the second locking nail of FIG. 8;

FIG. 10 shows a cross-sectional schematic view of the second locking staple of FIG. 9;

FIG. 11 shows a cross-sectional schematic view of a third locking nail of the intramedullary nail assembly of FIG. 1;

FIG. 12 shows a schematic front view of a first locking nail of the intramedullary nail assembly of FIG. 1;

FIG. 13 shows a cross-sectional schematic view of the first locking nail of FIG. 12;

FIG. 14 shows a cross-sectional schematic view of a second locking nail of the intramedullary nail assembly of FIG. 1;

FIG. 15 shows an exploded view of a second locking nail of the intramedullary nail assembly of FIG. 1.

Wherein the figures include the following reference numerals:

4. the femur; 10. a first locking nail; 11. a first inclined hole; 111. a first bore section; 112. a second bore section; 12. a second inclined hole; 13. a fourth polished rod segment; 14. a fifth polished rod segment; 20. a second locking pin; 21. a threaded segment; 211. a first lever body portion; 212. a second shaft portion; 213. a first stopper groove; 214. a second stopper groove; 215. a first flexible layer; 216. screw teeth; 22. a first trench; 23. a second trench; 24. a second flexible layer; 25. a third polished rod segment; 251. an operation slot; 30. a third locking pin; 31. a flexible portion; 32. an operation hole; 33. a first external thread section; 34. a first polished rod segment; 341. a first nail section; 342. a second nail section; 35. a second polished rod segment; 36. a second outer thread section; 40. an air bag; 50. transverse nails; 61. a receiving cylinder; 62. a butting part; 63. an axial slot; 64. axial ribs; 65. a limiting groove section; 66. a limit ring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

As shown in fig. 1 to 8, the intramedullary nail assembly of the present embodiment includes: a first locking nail 10, a second locking nail 20 and a third locking nail 30. The second locking pin 20 is inserted into the first end of the first locking pin 10, and the axis of the second locking pin 20 is disposed obliquely to the axis of the first locking pin 10. The third locking pin 30 is inserted in the middle of the first locking pin 10, the axis of the third locking pin 30 is arranged obliquely with respect to the axis of the first locking pin 10, and the third locking pin 30 supports the second locking pin 20 such that a triangular region is defined among the first locking pin 10, the second locking pin 20 and the third locking pin 30. Wherein, a first axial through hole is arranged in the second locking nail 20, the second locking nail 20 comprises a threaded section 21, and the third locking nail 30 supports the threaded section 21. The threaded section 21 comprises a rod body part and a thread 216 arranged on the rod body part, and a plurality of first grooves 22 are arranged on the thread 216.

By applying the technical scheme of the embodiment, the threaded section 21 comprises a rod body part and a screw thread 216 arranged on the rod body part, and a plurality of first grooves 22 are arranged on the screw thread 216. In the process of implanting the intramedullary nail assembly into a femur, the first locking nail 10 is driven, the second locking nail 20 penetrates through the first end of the first locking nail 10 along the guide wire in the first axial through hole, the fracture end is pressurized through the second locking nail 20, the third locking nail 30 penetrates through the middle of the first locking nail 10, and the third locking nail 30 supports the second locking nail 20. After the intramedullary locking nail component is implanted, the intramedullary locking nail component integrally bears pressure. When the second locking nail 20 is stressed, the thread section 21 of the second locking nail 20 is screwed in to compress bone substances in the femur, the screw teeth 216 provided with the plurality of first grooves 22 enable the screw teeth 216 to have elasticity and generate micro deformation, the elastic modulus of the intramedullary locking nail assembly is reduced, the screw teeth 216 can adapt to the surrounding bone substances, so that the bone substances around the screw teeth 216 are inserted into the first grooves 22 to be occluded and locked, stress shielding is reduced, and the bone substances can be effectively prevented from being further cut and the second locking nail 20 can penetrate out of the femur. Therefore, the technical scheme of the embodiment can solve the problem that the intramedullary nail in the related art penetrates out of the femur.

It should be noted that the middle of the first locking nail 10 is a position located between the first end of the first locking nail 10 and the second end of the first locking nail 10. The second locking nail 20 of the present embodiment mainly supports the tension trabecular bone in the femur, and the third locking nail 30 mainly supports the tension trabecular bone in the femur.

As shown in fig. 8 to 10, when the threaded section 21 of the second locking nail 20 is screwed in, the bone material in the femur is compressed, since the plurality of first grooves 22 located on the same circle of the screw teeth 216 are radially arranged, so that each first groove 22 is adapted to the embedded bone material, and the radially arranged plurality of first grooves 22 can engage more bone material while reducing the elastic modulus of the second locking nail 20, so that the screw teeth 216 can effectively adapt to the surrounding bone material.

It should be noted that, the plurality of first grooves 22 are radially arranged, which means that the side walls of the plurality of first grooves 22 may diverge in a straight direction or in a curved direction.

As shown in fig. 4, 8 to 10, the height of the thread 216 of the thread section 21 is gradually reduced from the distance from the first locking nail 10 to the proximity of the first locking nail 10. In this way, the screw thread 216 of the threaded section 21 is higher at the portion far from the first locking nail 10 and is embedded deeper into the bone, so that the bone can be gripped, and at the same time, since the screw thread 216 of the threaded section 21 is lower at the portion near the first locking nail 10, the strength is higher, so that sufficient strength can be provided for the portion of the screw thread 216 far from the first locking nail 10.

As shown in fig. 4 and 8 to 10, the rod body portion includes a first rod body portion 211 and a second rod body portion 212, the first rod body portion 211 is of a polished rod structure, and a portion of the second rod body portion 212 located between two adjacent threads 216 is provided with a plurality of second grooves 23. In this way, in the process of compressing the bone in the femur when the threaded section 21 of the second locking nail 20 is screwed in, since the first rod body 211 is of a polished rod structure, the screwing resistance of the threaded section 21 can be reduced, so that the screw teeth 216 on the first rod body 211 can be screwed into deeper bone, and more bone can be simultaneously allowed to be embedded into the plurality of first grooves 22 and the plurality of second grooves 23, so that the elastic modulus of the second locking nail 20 is closer to that of the bone, the self-adaptation condition of the screw teeth 216 and the surrounding bone is satisfied, and the bone cutting and the second locking nail 20 can be further prevented from penetrating out of the femur 4.

Specifically, the sidewalls of the plurality of second grooves 23 located on the same turn of the thread 216 are parallel to the axis of the rod body.

As shown in fig. 4, 8 to 10, in order to achieve better engagement locking of the screw teeth 216 on the rod body portion, the axial dimension of the first rod body portion 211 is larger than the axial dimension of the second rod body portion 212. The first lever part 211 is provided with a first stopper groove 213, the second lever part 212 is provided with a second stopper groove 214 communicating with the first stopper groove 213, and the end of the third locking pin 30 is positioned in the first stopper groove 213 and the second stopper groove 214. The first and

second stopper grooves

213 and 214 respectively restrict both sides of the end portion of the third locking nail 30 to prevent the third locking nail 30 from being misaligned while supporting the second locking nail 20, so that the third locking nail 30 is reliably positioned at the supporting position.

As shown in fig. 3, 4, and 8 to 10, in order to reduce the load of the second locking nail 20 on the third locking nail 30, the end of the third locking nail 30 has a flexible portion 31. The flexible portion 31 can play a certain role of cushioning. In order to further reduce the load of the second locking nail 20 on the third locking nail 30, the threaded section 21 is provided with a first flexible layer 215. The first flexible layer 215 can also serve a certain cushioning effect. Like this, the pressure energy that intramedullary lock nail subassembly bore is stored and is dispersed by flexible portion 31 and first flexible layer 215, and through the flexible portion 31 and the load that is born in the twinkling of an eye of the intramedullary lock nail subassembly that is slowed down and weakened by being compressed of first flexible layer 215, guarantee that intramedullary lock nail subassembly can not produce instantaneous stress concentration to improve the stability that intramedullary lock nail subassembly was implanted, effectively prevent the effect of wearing out of second locking nail 20. Meanwhile, due to the arrangement of the flexible part 31 and the first flexible layer 215, the probability of metal debris particles caused by rigid metal collision can be effectively reduced, and the probability of postoperative bone resorption and inflammatory reaction is reduced.

In an embodiment not shown in the figures, the end of the third locking spike has a flexible portion. Or the first flexible layer is arranged on the thread section.

As shown in fig. 4 to 7 and 11, the middle portion of the first locking nail 10 is provided with a first inclined hole 11 through which the third locking nail 30 passes. The third locking screw 30 includes a first male screw section 33, and the first inclined hole 11 is provided with a female screw which is fitted in a tapered shape to the first male screw section 33. In this way, the third locking pin 30 penetrates obliquely upward to the middle of the first locking pin 10 along the path formed by the first inclined hole 11, so that the end of the third locking pin 30 smoothly reaches the first and

second stopper grooves

213 and 214, so that the third locking pin 30 effectively supports the second locking pin 20. And the first male screw section 33 is taper-fitted with the female screw on the first inclined hole 11 to lock the third locking nail 30 securely to the middle of the first locking nail 10, serving as a backstop effect. Specifically, the internal thread is an internal tapered thread and the first external thread section 33 is an external tapered thread.

As shown in fig. 4 to 7 and 11, a second axial through hole is provided in the first locking nail 10, and the first inclined hole 11 communicates with the second axial through hole. The first locking nail 10 is driven into the femur 4 along a guide wire in the second axial through hole. The second axial through hole separates the first inclined hole 11 to form a first hole section 111 and a second hole section 112. The third locking nail 30 further includes a first polished rod section 34 and a second polished rod section 35 at both ends of the first male screw section 33. In order to form the first external thread section 33 in a conical shape, the diameter of the second polished rod section 35 is larger than the diameter of the first polished rod section 34. The first polished rod section 34 passes through the first bore section 111 and the internal threads are provided on the second bore section 112. The first hole section 111 is a smooth hole, so that the first hole section 111 can smoothly guide the third locking nail 30 to smoothly implant the third locking nail 30 into the femur 4, and at the same time, when the end of the third locking nail 30 contacts the groove bottom walls of the first and

second stopper grooves

213 and 214, the first male screw section 33 is screwed with the female screw on the second hole section 112, and the third locking nail 30 is reliably locked at the middle of the first locking nail 10 while the implantation is performed.

As shown in fig. 4 to 7 and 11, the third locking nail 30 further includes a second external thread section 36 supporting the second locking nail 20, and the first polished rod section 34 is located between the second external thread section 36 and the first external thread section 33. The second external thread section 36 is arranged to make the end of the third locking pin 30 in line contact with the bottom walls of the first stopping groove 213 and the second stopping groove 214, and the flexible portion on the end of the third locking pin achieves a certain buffer when the second locking pin is deformed by downward pressure. The first polished rod section 34 can reduce the resistance generated during the screwing of the third locking nail 30 into the femur, and can enable the third locking nail 30 to be screwed into the femur 4 smoothly.

As shown in fig. 4, 14 and 15, the first polished rod segment 34 includes a first nail segment 341 and a second nail segment 342 movably engaged with the first nail segment 341, and a balloon 40 is disposed between a second end of the first nail segment 341 and a first end of the second nail segment 342. After the intramedullary locking nail assembly is implanted, the first end of the first nail section 341 is pressed, the air bag 40 between the second end of the first nail section 341 and the first end of the second nail section 342 is pressed to be in a compression state, the second end of the first nail section 341 is gradually close to the first end of the second nail section 342, so that the overall length of the third locking nail 30 is gradually reduced, the pressure energy borne by the intramedullary locking nail assembly is stored and dispersed by the air bag 40, the load instantaneously borne by the intramedullary locking nail assembly is relieved and weakened through the deformation of the air bag 40, the elastic modulus of the intramedullary locking nail assembly is reduced, and the stress shielding is reduced. Therefore, the 'ward triangle' can be effectively reconstructed, the stably supported intramedullary locking nail component is realized, the effective reduction and fixation of the head of the femur 4 of a patient can be well realized, the 'ward triangle' of the tuberosity part of the femur 4 can be reconstructed, the stress borne by the femur 4 can be better dispersed, and the intramedullary locking nail component implanted into the femur 4 is prevented from being cut out of the femur 4. The balloon 40 of this embodiment is filled with a gas, and the shape of the balloon 40 is preferably an ellipsoid, similar to a capsule. The outer wall of the balloon 40 is a high-toughness material. The deformation of the air bag 40 is used for relieving and weakening the load instantly borne by the intramedullary lock pin assembly, so that the third locking pin 30 can provide certain elastic support, the intramedullary lock pin assembly has elasticity, the possibility of stress concentration of the intramedullary lock pin assembly is effectively reduced, and the service life of the intramedullary lock pin assembly is prolonged. In particular, the intramedullary nail assembly is located at a proximal position of the femur 4, i.e. proximal to the femur. The high-toughness material is preferably latex.

As shown in fig. 4, 14 and 15, the second end of the first nail section 341 is provided with an accommodating cylinder 61 for accommodating the air bag 40, and the first end of the second nail section 342 is provided with a top part 62 opposite to the mouth of the accommodating cylinder 61 and press-fitted with the air bag 40. The accommodating barrel 61 is provided to facilitate the third locking nail 30 to accommodate the air bag 40, so that the structure of the third locking nail 30 is compact, and at the same time, the abutting portion 62 presses the air bag 40, so that the air bag 40 can be switched from the expanded state to the compressed state. The abutment portion 62 may be an abutment table or an abutment post.

As shown in fig. 4, 14 and 15, in the process of inserting the third locking nail 30 into the middle of the first locking nail 10 and screwing the third locking nail into the femur, in order to prevent the second nail section 342 and the first nail section 341 from rotating relatively, the first rotation stopping portion on the outer wall of the accommodating barrel 61, the first end of the second nail section 342 of the first nail section 341 is further provided with a second rotation stopping portion on the side of the abutting portion 62, and the second rotation stopping portion is in rotation stopping fit with the first rotation stopping portion. Like this, through the cooperation of second rotation-stopping portion and the rotation-stopping of first rotation-stopping portion, when screwing in second nail section 342, first nail section 341 can rotate along with second nail section 342 to make third locking nail 30 can wear to establish the middle part at first locking nail 10.

As shown in fig. 4, 14 and 15, the first rotation stopping portion includes an axial groove 63, and the second rotation stopping portion includes an axial rib 64 engaged with the axial groove 63, so that when the first nail section 341 is forced and moves relative to the second nail section 342, the axial rib 64 can move in the axial groove 63 to perform a guiding function, and at the same time, the groove sidewall of the axial groove 63 contacts with the sidewall of the axial rib 64 to prevent the first nail section 341 from rotating relative to the second nail section 342.

As shown in fig. 4, 14 and 15, the axial grooves 63 are four at intervals in the circumferential direction of the accommodating cylinder 61, the axial ribs 64 are four at intervals in the circumferential direction of the first end of the second nail section 342, and the four axial grooves 63 are provided in one-to-one correspondence with the four axial ribs 64. In this way, when the second nail section 342 is twisted with the first nail section 341, the third locking nail 30 has sufficient structural strength, and the structural stability of the third locking nail 30 can be ensured. The number of axial grooves 63 and axial ribs 64 may not be limited to four, but may also be one, two, three, five or more.

As shown in fig. 4, 14 and 15, the accommodating cylinder 61 is disposed on the second end of the first nail section 341, a limiting groove section 65 is disposed between the accommodating cylinder 61 and the second end of the first nail section 341, the axial rib 64 is disposed on the first end of the second nail section 342, a limiting ring 66 is disposed at an end of the axial rib 64, and the limiting ring 66 is movably disposed in the limiting groove section 65 along the axial direction of the first nail section 341 so that the abutting portion 62 presses or releases the airbag 40. The limiting ring 66 is located in the limiting groove section 65, and can limit the moving range of the first nail section 341 relative to the second nail section 342, and prevent the first nail section 341 and the second nail section 342 from being disengaged. Specifically, in the process that the first nail section 341 moves relative to the second nail section 342, when the limit ring 66 abuts against the side wall of the limit groove section 65 close to the first end of the first nail section 341, the abutting part 62 presses the airbag 40 to enable the airbag 40 to be in a compressed state, and when the limit ring 66 abuts against the side wall of the limit groove section 65 far away from the first end of the first nail section 341, the abutting part 62 releases the airbag 40 to enable the airbag 40 to be in an expanded state.

In order to facilitate connection, processing and assembly, the limiting ring 66 and the axial rib 64 are in a split structure and are connected by welding, bonding or screwing, and the accommodating barrel 61 and the first nail section 341 are in a split structure and are connected by welding, bonding or screwing.

As shown in fig. 4 to 7 and 13, the first end of the first locking pin 10 is provided with a second inclined hole 12 for the second locking pin 20 to pass through, and the included angle between the axis of the second inclined hole 12 and the axis of the first locking pin 10 is larger than the included angle between the axis of the first inclined hole 11 and the axis of the first locking pin 10. Thus, the second angled hole 12 is angled slightly upward to ensure that the third locking pin 30 is implanted through the second locking pin 20 from the second angled hole 12 and adjacent to the upper sidewall of the femur 4, and the greater angle of the first angled hole 11 ensures that the third locking pin is implanted adjacent to the inner sidewall of the femur 4.

Since the first locking pin 10 is in rigid contact with the second locking pin 20, in order to avoid rigid collision, a second flexible layer 24 is disposed between the second locking pin 20 and the second inclined hole 12. Thus, the second flexible layer 24 can bear pressure and deform, can effectively prevent rigid collision, can effectively reduce the probability of metal debris particles caused by metal rigid collision, and reduce the probability of postoperative bone resorption and inflammatory reaction. The second flexible layer 24 is embedded in the second inclined hole 12 by injection molding to form a flexible gasket.

As shown in fig. 4 to 7 and 13, the second inclined hole 12 is a stepped hole, and the second locking nail 20 further includes a third polished rod section 25 connected to the threaded section 21, the third polished rod section 25 passing through the second inclined hole 12 and having a stepped section engaged with the second inclined hole 12. Like this, the in-process that second locking nail 20 screwed into to the thighbone, ladder section and shoulder hole backstop cooperation, second locking nail 20 is twisted in place this moment, prevents that second locking nail 20 from continuing to twist, plays spacing effect. The provision of the threaded section 21 facilitates the screwing of the second locking nail 20 into the femur 4.

As shown in fig. 1 to 4, an end of the third polished rod segment 25 away from the threaded segment 21 is provided with an operation groove 251. The arrangement of the operation groove 251 makes the operation convenient. After the second locking nail 20 is implanted in the femur 4, the second end of the second locking nail 20 can be exposed out of the outer sidewall of the femur 4, so that the operation groove 251 on the second end of the second locking nail 20 can also be exposed out of the femur 4. The operation groove 251 may be driven using a screwdriver tool.

As shown in fig. 1 to 4, an end of the third locking nail 30 remote from the first male screw section 33 is provided with an operation hole 32. The operation hole 32 is provided to drive the third locking nail 30 to rotate, and the operation hole 32 is preferably a hexagon socket so that a hexagon socket wrench can be used to insert into the operation hole 32 and drive the third locking nail 30 to rotate, so that the third locking nail 30 can achieve the effect of resetting and pressurizing the fractured end.

As shown in fig. 1 to 4, the first locking pin 10 includes a fourth polished rod section 13 and a fifth polished rod section 14 connected to the fourth polished rod section 13, an outer diameter of the fourth polished rod section 13 is larger than an outer diameter of the fifth polished rod section 14, the third polished rod section 25 is inserted into a first end of the fourth polished rod section 13, and an end of the third locking pin 30, at which the operation hole 32 is disposed, is located on a side of a second end of the fourth polished rod section 13. Thus, the length of the third locking nail 30 is long, so that after the third locking nail 30 is implanted into the femur 4, the bottom end of the third locking nail 30 can be exposed out of the outer side wall of the femur 4, so that the operation hole 32 on the bottom end of the third locking nail 30 can also be exposed out of the femur 4.

As shown in fig. 1-4, 12 and 13, the intramedullary nail assembly further includes a transverse nail 50 disposed through fifth smooth shank segment 14. The provision of the transverse nail 50 facilitates locking the fifth polished rod segment 14 into the femur, improving the stability of the overall structure of the intramedullary nail assembly.

The first locking nail 10, the second locking nail 20 and the third locking nail 30 of the present embodiment are preferably made of a medical titanium alloy material, the first flexible layer 215 and the second flexible layer 24 are preferably made of a bio-polycarbonate Polyurethane (PCU) material, and the bio-polycarbonate polyurethane material has a good strength, has a certain flexibility and elasticity, and can satisfy a certain elastic deformation. The flexible portion 31 is preferably made of a Polyetheretherketone (PEEK) plastic material having good biocompatibility and an elastic modulus close to that of human bone, and the flexible portion 31 and the third locking nail 30 can be connected by injection molding. The first flexible layer 215 and the second locking pin 20 may be connected by injection molding.

In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, horizontal" and "top, bottom", etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element being referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be considered as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An intramedullary locking nail assembly, comprising:

a first locking nail (10);

the second locking nail (20) is arranged at the first end of the first locking nail (10) in a penetrating way, and the axis of the second locking nail (20) is obliquely arranged relative to the axis of the first locking nail (10);

a third locking nail (30) arranged in the middle of the first locking nail (10), wherein the axis of the third locking nail (30) is inclined relative to the axis of the first locking nail (10), the third locking nail (30) supports the second locking nail (20),

the second locking nail (20) comprises a threaded section (21), the third locking nail (30) supports the threaded section (21), the threaded section (21) comprises a rod body portion and a screw thread (216) arranged on the rod body portion, and a plurality of first grooves (22) are formed in the screw thread (216).

2. The intramedullary nail assembly of claim 1, wherein the first plurality of flutes (22) on the same ring of threads (216) are radially disposed.

3. Intramedullary nail assembly according to claim 1, characterized in that the height of the threads (216) of the threaded section (21) decreases progressively from the distance from the first locking nail (10) to the proximity of the first locking nail (10).

4. The intramedullary nail assembly of claim 1, wherein the shank portion comprises a first shank portion (211) and a second shank portion (212), the first shank portion (211) is of a polished rod structure, and a portion of the second shank portion (212) between two adjacent threads (216) is provided with a plurality of second grooves (23).

5. The intramedullary nail assembly of claim 4, wherein the first shank portion (211) has an axial dimension greater than an axial dimension of the second shank portion (212), the first shank portion (211) having a first stop groove (213) disposed thereon, the second shank portion (212) having a second stop groove (214) disposed thereon in communication with the first stop groove (213), an end of the third locking nail (30) being disposed within the first stop groove (213) and the second stop groove (214).

6. Intramedullary nail assembly according to claim 1, characterized in that the end of the third locking nail (30) has a flexible portion (31); and/or a first flexible layer (215) is arranged on the thread section (21).

7. The intramedullary nail assembly of claim 1,

the middle part of first locking nail (10) is provided with the confession third locking nail (30) pass first inclined hole (11), third locking nail (30) include first external screw thread section (33), be provided with on first inclined hole (11) with first external screw thread section (33) taper fit's internal thread.

8. The intramedullary nail assembly of claim 7,

a second axial through hole is formed in the first locking nail (10), the first inclined hole (11) is communicated with the second axial through hole, the second axial through hole separates the first inclined hole (11) to form a first hole section (111) and a second hole section (112), the third locking nail (30) further comprises a first polished rod section (34) and a second polished rod section (35) which are positioned at two ends of the first external thread section (33), the diameter of the second polished rod section (35) is larger than that of the first polished rod section (34), the first polished rod section (34) penetrates through the first hole section (111), and the internal thread is arranged on the second hole section (112);

the third locking nail (30) further comprises a second external thread section (36) supporting the second locking nail (20), and the first polished rod section (34) is located between the second external thread section (36) and the first external thread section (33).

9. Intramedullary nail assembly according to claim 7, characterized in that the first end of the first locking nail (10) is provided with a second inclined hole (12) for the second locking nail (20) to pass through, the angle between the axis of the second inclined hole (12) and the axis of the first locking nail (10) being greater than the angle between the axis of the first inclined hole (11) and the axis of the first locking nail (10), a second flexible layer (24) being provided between the second locking nail (20) and the second inclined hole (12).

10. The intramedullary nail assembly of claim 9,

the second inclined hole (12) is a stepped hole, the second locking nail (20) further comprises a third polished rod section (25) connected with the threaded section (21), and the third polished rod section (25) penetrates through the second inclined hole (12) and is provided with a stepped section matched with the second inclined hole (12);

an operating groove (251) is formed in one end, far away from the threaded section (21), of the third polished rod section (25);

an operating hole (32) is formed in one end, far away from the first external thread section (33), of the third locking nail (30);

the first locking nail (10) comprises a fourth polished rod section (13) and a fifth polished rod section (14) connected with the fourth polished rod section (13), the outer diameter of the fourth polished rod section (13) is larger than that of the fifth polished rod section (14), the third polished rod section (25) penetrates through the first end of the fourth polished rod section (13), and one end, provided with the operation hole (32), of the third locking nail (30) is located on one side of the second end of the fourth polished rod section (13);

the intramedullary nail assembly further includes a transverse nail (50) disposed through the fifth shank segment (14).