CN110301969B

CN110301969B - Intramedullary nail

Info

Publication number: CN110301969B
Application number: CN201910439152.4A
Authority: CN
Inventors: 袁航; 杨永竤
Original assignee: Zhejiang Hospital
Current assignee: Zhejiang Hospital
Priority date: 2019-05-24
Filing date: 2019-05-24
Publication date: 2020-12-15
Anticipated expiration: 2039-05-24
Also published as: CN110301969A

Abstract

The invention relates to the field of medical instruments and discloses an intramedullary nail, which comprises a nail rod (1), wherein the nail rod (1) is a hollow rod body and further comprises an inner rod (2) extending into a hollow inner cavity of the nail rod (1), one end of the nail rod (1) is defined as a fixed end and is fixed on a bone, the other end of the nail rod (1) is an expansion end and is provided with expansion pieces (3), at least two expansion pieces (3) are arranged, and the inner rod (2) is in contact with the inner sides of the expansion pieces (3) and outwards supports the expansion pieces (3); the two expansion pieces (3) are arranged symmetrically about the axial direction of the nail rod (1); the expansion piece (3) comprises a lower part (31) and an upper part (32) which are connected with each other. The intramedullary nail has a simple structure, the expansion end of the intramedullary nail is arranged through the expansion piece, the intramedullary nail is convenient to install in a bone, the disassembly is also facilitated, in addition, the wound surface of the intramedullary nail is small, and the infection of a wounded person is not easy to cause.

Description

Intramedullary nail

Technical Field

The invention relates to the field of medical instruments, in particular to an intramedullary nail.

Background

The intramedullary nail is a more commonly used intramedullary fixing device, has the advantages of high strength, small wound and fast healing compared with other intramedullary fixations, has ideal reduction and fixation to the fracture, is a more commonly used means for treating the fracture, and is guided and inserted into the intramedullary nail by opening the bone end, and the intramedullary nail reduces and fixes the fractured bone along the physiological curvature of the medullary cavity in the medullary cavity.

When a bone of a human body is fractured, an intramedullary nail, which generally means a long steel nail placed in a bone marrow cavity, is generally used to connect the fractured bones. For example, after an intramedullary nail is placed in a femur and a tibia of a lower limb after a wound is formed at one end of a bone, a tension screw and a fixing nail are respectively installed at the near end and the far end of the intramedullary nail, so that the rotation and shortening of the bone can be prevented. The installation of an intramedullary nail usually requires two open wounds to be made on the injured person for fixation of the intramedullary nail.

At present, the utility model with the patent number 201020168216.6, named intramedullary nail, has the advantages that the near end of the intramedullary nail rod is provided with an oblique non-circular tension hole which is matched with a tension screw with a corresponding shape, and after the tension screw is installed on the intramedullary nail, the tension screw can not rotate, so that the uncomfortable feeling of a wounded person is reduced; the tail section of the long through hole of the intramedullary nail rod is sequentially provided with a sealing cap screw hole and a compression screw hole, so that the tension screw can be compressed after the compression nut is arranged in the compression screw hole, and the tension screw is not easy to slide; the far end of the intramedullary nail rod is provided with a plurality of decompression planes, the structure ensures that marrow and marrow blood flow is smooth after the injured person installs the intramedullary nail, and the healing speed of the fracture part is high; the two ends of the tension hole on the intramedullary nail rod are provided with the positioning platforms, and the structure ensures that the tension hole on the intramedullary nail rod can be accurately aligned when the tension screw is installed; the tail of the proximal end of the intramedullary nail rod is provided with a groove, and the structure can play a role in assisting the installation of the intramedullary nail.

However, at least two positioning platforms in the prior art have the defects of more wound surfaces, complex disassembly and easy infection caused by installation.

Disclosure of Invention

Aiming at the defects of more wound surfaces, complex disassembly and easy infection in the prior art, the invention provides the intramedullary nail.

In order to solve the technical problem, the invention is solved by the following technical scheme:

the intramedullary nail comprises a nail rod which is a hollow rod body and further comprises an inner rod extending into a hollow inner cavity of the nail rod, one end of the nail rod is defined as a fixed end and fixed on a bone, the other end of the nail rod is an expansion end and is provided with expansion pieces, the expansion pieces are at least two, and the inner rod is in contact with the inner sides of the expansion pieces and outwards expands the expansion pieces.

Preferably, the expansion pieces are two and are arranged symmetrically with respect to the axial direction of the nail shank.

Preferably, the expansion piece comprises a lower part and an upper part which are mutually connected and integrally formed, the lower part is connected with the nail rod, a positioning groove matched with the outer surface of the inner rod is arranged on the inner wall of the lower part, an inward convex block is arranged on the upper part, and the outer surface of the inner rod is in contact fit with the convex block and expands the expansion piece outwards.

Preferably, an inclined surface is arranged on one side of the convex block close to the lower part, and a chamfer is arranged on one end part of the inner rod inserted into the expansion piece.

Preferably, the thickness of the end of the upper part extending upwards is gradually reduced.

Preferably, the expansion piece further comprises a middle part, the lower part and the upper part are connected through the middle part, the lower part, the middle part and the upper part are integrally formed, one side of the middle part, which is close to the axis of the inner rod, is defined as the inner side of the middle part, and the inner side of the middle part is provided with a recess.

Preferably, the expansion tab is integrally formed with the expansion end of the shank.

Preferably, the inner rod is provided with a first external thread, the fixed end of the nail rod is provided with a positioning groove, the nail rod further comprises an inner rod seat, the inner rod seat is provided with a first internal thread matched with the first external thread of the inner rod, and the inner rod seat is further provided with a positioning lug matched with the positioning groove; the fixed end of the nail rod is provided with a second internal thread and further comprises a fixed seat, the fixed seat is provided with a second external thread matched with the second internal thread, and the fixed seat is fixed on the nail rod through the matching of the second internal thread and the second external thread.

Preferably, the fixed end of the shank has a diameter greater than the diameter of the enlarged end of the shank.

Preferably, the shank has a curvature conforming to a human leg bone.

Due to the adoption of the technical scheme, the invention has the remarkable technical effects that: the intramedullary nail of this application simple structure, the setting of expansion end through the expansion piece of intramedullary nail not only makes things convenient for the intramedullary nail to install in the bone, also is favorable to dismantling, and in addition, the surface of a wound of this application is little, is difficult for causing wounded's infection.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a schematic view i of a portion of fig. 1.

Fig. 3 is a partial schematic view ii of fig. 1.

Fig. 4 is a schematic view iii of a partial structure of fig. 1.

The names of the parts indicated by the numerical references in the drawings are as follows: 1-nail rod, 2-inner rod, 3-expansion piece, 4-fixed seat, 5-inner rod seat, 11-positioning groove, 21-chamfer, 31-lower part, 32-upper part, 33-middle part, 311-positioning groove, 321-convex block, 3211-inclined plane, 331-concave and 51-positioning convex block.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Example 1

Intramedullary nail, as shown in the figure, including nail pole 1, nail pole 1 is the hollow body of rod, still including stretching into interior pole 2 in the hollow inner chamber of nail pole 1, the one end definition of nail pole 1 is the stiff end and fixes on the bone, the other end of nail pole 1 is for expanding the end and being equipped with expansion piece 3, expansion piece 3 has two at least, and expansion piece 3 is close to one side definition of interior pole 2 and is its inboard, interior pole 2 and expansion piece 3's inboard contact and will expand piece 3 and outwards strut.

The expansion pieces 3 are two and are arranged symmetrically about the axial direction of the nail rod 1. The expansion sheet 3 has elasticity, and after the expansion sheet 3 is expanded by the inner rod 2, the expansion sheet can be expanded outwards and the diameter of the expansion end of the nail rod 1 is increased, and the expanded nail rod 1 can be installed in bone marrow.

The expansion piece 3 comprises a lower part 31 and an upper part 32 which are connected with each other and integrally formed, the lower part 31 is connected with the nail rod 1, the outer surfaces of the lower part 31 and the lower part 32 are smoothly connected with the outer surface of the nail rod 1 to form a smooth arc-shaped surface, a positioning groove 311 matched with the outer surface of the inner rod 2 is arranged on the inner wall of the lower part 31, the upper part 32 is provided with a convex block 321 which protrudes inwards, and the outer surface of the inner rod 2 is contacted and matched with the convex block 321 and expands the expansion piece 3 outwards.

The thickness of the lower part 31 is thicker, symmetrical positioning grooves 311 are arranged between the two expansion sheets 3, the lower part 31 is wrapped outside the inner rod 2, and the sliding direction of the inner rod 2 is controlled through the positioning grooves 311; the convex blocks 311 on the upper parts 31 of the two expansion pieces 3 are also symmetrically arranged, when the inner rod 2 is not inserted, the convex blocks 311 on the two expansion pieces 3 are close to each other, when the inner rod 2 is inserted, the inner rod 2 outwards expands the convex blocks 311, and the convex blocks 311 drive the expansion ends of the expansion pieces 3 to outwards expand.

The side of the projection 321 near the lower portion 31 is provided with a slope 3211, and the end of the inner rod 2 inserted into the expansion piece 3 is provided with a chamfer 21. The chamfer 21 of the inner rod 2 contacts the inclined surface 3211 and slides into the gap of the two projections 321 and expands the expansion tabs 3.

The upwardly extending end of the upper portion 32 tapers in thickness.

The diameter of the fixed end of the nail rod 1 is larger than that of the expansion end of the nail rod 1.

The nail rod 1 has a radian conforming to the leg bone of a human body.

When the nail rod is used, the inner rod 2 in the nail rod 1 is firstly pulled out, so that the expansion end of the nail rod 1 is in an unexpanded state, the expansion end of the nail rod 1 is inserted into bone marrow, the inner rod 2 is inserted after the nail rod 1 is positioned at a designated position, the inner rod 2 slides into a gap formed by the two convex blocks 321 and outwards expands the expansion sheet 3, the expansion sheet 3 is tightly expanded on the inner wall of a bone, and then the positions of the nail rod 1 and the inner rod 2 are positioned through the fixing seat 4.

Example 2

The same as in example 1, except that there are three expansion pieces 3.

Example 3

The same as in example 1, except that there are four expansion pieces 3.

Example 4

The same as in embodiment 1, except that the expansion piece 3 further comprises a middle portion 33, the lower portion 31 and the upper portion 32 are connected by the middle portion 33, the lower portion 31, the middle portion 33 and the upper portion 32 are integrally formed, one side of the middle portion 33 near the axis of the inner rod 2 is defined as an inner side thereof, and a recess 331 is formed on the inner side of the middle portion 33. The thickness of middle part 33 is less than the thickness of lower part 31, and the thickness of middle part 33 is less, makes expansion piece 3 can effectively utilize middle part 33 to warp, is favorable to expanding outwards of expansion piece 3, and can prevent that expansion piece 3 from splitting at the in-process that expands, makes expansion piece 3 have toughness.

The expansion piece 3 is integrally formed with the expansion end of the nail rod 1.

Example 5

The nail comprises the same structure as the embodiment 1, except that the inner rod 2 is provided with a first external thread, the fixed end of the nail rod 1 is provided with a positioning groove 11, the nail further comprises an inner rod seat 5, the inner rod seat 5 is provided with a first internal thread matched with the first external thread of the inner rod 2, and the inner rod seat 5 is also provided with a positioning lug 51 matched with the positioning groove 11; be equipped with the second internal thread on the stiff end of nail pole 1, still include fixing base 4, be equipped with on fixing base 4 with second internal thread complex second external thread, fix interior pole seat 5 on nail pole 1 through the cooperation of second internal thread and second external thread on fixing base 4.

Interior pole seat 5 is adjusted interior pole 2 through first internal thread and is stretched into length in nail pole 1, and when adjusting good back, interior pole seat 5 passes through constant head tank 11 to be fixed on nail pole 1 and make interior pole seat 5 unable rotatory, and the screw-thread fit through fixing base 4 makes interior pole seat 5 fix on nail pole 1 at last.

When the intramedullary nail is dismantled to recovered needs of patient, medical practitioner can take out interior pole 2 through the dismantlement to fixing base 4, interior pole 2 is extracting the in-process of nail pole 1, breaks away from the lug 311 of two expansion pieces 3, and the inboard of expansion piece 3 loses behind the outside thrust of interior pole 2, just automatic inside closure, leads to the diameter of two expansion pieces 3 to diminish, and medical practitioner can realize dismantling outside taking out the bone with nail pole 1.

In summary, the above-mentioned embodiments are only preferred embodiments of the present invention, and all equivalent changes and modifications made in the claims of the present invention should be covered by the claims of the present invention.

Claims

1. Intramedullary nail, including nail pole (1), its characterized in that: the nail rod (1) is a hollow rod body and further comprises an inner rod (2) extending into a hollow inner cavity of the nail rod (1), one end of the nail rod (1) is defined as a fixed end and fixed on a bone, the other end of the nail rod (1) is an expansion end and is provided with expansion pieces (3), at least two expansion pieces (3) are arranged, and the inner rod (2) is in contact with the inner side of each expansion piece (3) and outwards supports the expansion pieces (3); the expansion piece (3) comprises a lower part (31) and an upper part (32) which are connected with each other, the lower part (31) is connected with the nail rod (1), a positioning groove (311) matched with the outer surface of the inner rod (2) is arranged on the inner wall of the lower part (31), a convex block (321) protruding inwards is arranged on the upper part (32), and the outer surface of the inner rod (2) is in contact fit with the convex block (321) and outwards supports the expansion piece (3); the nail comprises an inner rod (2), a first outer thread, a positioning groove (11) and an inner rod seat (5), wherein the fixed end of the nail rod (1) is provided with the positioning groove (11), the inner rod seat (5) is provided with a first inner thread matched with the first outer thread of the inner rod (2), and the inner rod seat (5) is also provided with a positioning lug (51) matched with the positioning groove (11); be equipped with the second internal thread on the stiff end of nail pole (1), still include fixing base (4), be equipped with on fixing base (4) with second internal thread complex second external screw thread, fixing base (4) are fixed interior pole seat (5) on nail pole (1) through the cooperation of second internal thread and second external screw thread.

2. The intramedullary nail of claim 1, wherein: the expansion pieces (3) are two and are arranged symmetrically relative to the axial direction of the nail rod (1).

3. The intramedullary nail of claim 1, wherein: an inclined plane (3211) is arranged on one side of the convex block (321) close to the lower part (31), and a chamfer (21) is arranged on one end part of the inner rod (2) inserted into the expansion sheet (3).

4. The intramedullary nail of claim 1, wherein: the thickness of the end of the upper part (32) extending upwards is gradually reduced.

5. Intramedullary nail according to claim 1 or 3 or 4, characterized in that: the expansion piece (3) further comprises a middle part (33), the lower part (31) and the upper part (32) are connected through the middle part (33), the lower part (31), the middle part (33) and the upper part (32) are integrally formed, one side, close to the axis of the inner rod (2), of the middle part (33) is defined as the inner side of the middle part, and a recess (331) is formed in the inner side of the middle part (33).

6. The intramedullary nail of claim 1, wherein: the expansion sheet (3) and the expansion end of the nail rod (1) are integrally formed.

7. The intramedullary nail of claim 1, wherein: the diameter of the fixed end of the nail rod (1) is larger than that of the expansion end of the nail rod (1).

8. The intramedullary nail of claim 1, wherein: the nail rod (1) has a radian which is in accordance with the leg bone of a human body.