ROTATION PREVENTION MEMBER OF LEG SCREW FOR FIXING BONE

Abstract

The present disclosure relates to a rotation prevention member of a leg screw for fixing a bone that is configured to prevent rotation of a leg crew that is coupled to a nail in a medullary cavity such as a femur and fixes a fracture portion. The rotation prevention member of a leg screw for fixing a bone, in which a femoral nail is fitted in an end of a femoral marrow, a leg screw combined with a cap is laterally inserted in a transverse hole formed at an angle with respect to a longitudinal axis of the nail, and the leg screw is fixed to be longitudinally movable without rotating in the transverse hole, includes: pin guide grooves formed symmetric to each other in a longitudinal direction of the leg screw; a superelastic member inserted in the pin guide grooves; and a cap thread-fastened to a rear surface of the leg screw to prevent separation of the superelastic member in order to prevent rotation between a threaded portion of the leg screw and a bone due to rotation after a fracture part is occupied.

Claims

1. A rotation prevention member of a leg screw for fixing a bone, in which a femoral nail is fitted in an end of a femoral marrow, a leg screw combined with a cap is laterally inserted in a transverse hole formed at an angle with respect to a longitudinal axis of the nail, and the leg screw is fixed to be longitudinally movable without rotating in the transverse hole, the rotation prevention member comprising: a pin guide grooves formed symmetric to each other in a longitudinal direction of the leg screw; a superelastic member inserted in the pin guide grooves; and a cap thread-fastened to a rear surface of the leg screw to prevent separation of the superelastic member in order to prevent rotation between a threaded portion of the leg screw and a bone due to rotation after a fracture part is occupied.

2. The rotation prevention member of claim 1, wherein the pin guide grooves are formed on a body to which the cap is coupled, and the threaded portion.

3. The rotation prevention member of claim 1, wherein the pin guide grooves are formed a long spiral shape.

4. The rotation prevention member of claim 2, wherein the superelastic member has Pseudoelasticity or superelasticity.

5. The rotation prevention member of claim 2, wherein the superelastic member has a connecting rod formed in a thin pin shape at a first end thereof, and elastic pins integrally bend from both ends of the connecting rod, respectively.

Description

DESCRIPTION OF DRAWINGS

[0038] FIG. 1 is a cross-sectional view showing a portion of a nail of the related art positioned in a femur and a leg screw disposed through a transverse hole of the nail to attenuate a fracture in a femoral neck.

[0039] FIG. 2 is a view showing a surgery for a fracture using a locking member of the related art fitted in a longitudinal slot of a leg screw.

[0040] FIG. 3 is an exploded perspective view of a rotation prevention member of a leg screw for fixing a bone according to the present disclosure.

[0041] FIGS. 4A to 4C are views showing a process of assembling the rotation prevention member of a leg screw for fixing a bone, in which

[0042] FIG. 4A is a view showing the state before a superelastic member is coupled to a leg screw,

[0043] FIG. 4B is a view showing the state in which the superelastic member is partially inserted in pin guide grooves of the leg screw, and FIG. 4C is a view showing the state in which a cap is coupled with the superelastic member fully inserted in the leg screw.

[0044] FIG. 5 is an enlarged view showing main parts when the superelastic member and the cap are coupled to the leg screw according to the present disclosure.

[0045] FIG. 6 is a cross-sectional view showing the state in which a leg screw has been implanted in a medullary cavity and then the rotation prevention member of the present disclosure has been implanted.

BEST MODE

[0046] Hereafter, the configuration of a rotation prevention member of a leg screw for fixing a bone of the present disclosure is described in detail with reference to the drawings.

[0047] However, the disclosed drawings are provided as examples so that the spirit of the present disclosure can be sufficiently transmitted to those skilled in the art. Accordingly, the present disclosure is not limited to the proposed drawings and may be implemented by other ways.

Further, unless stated otherwise, the terms used herein have meanings that those skilled in the art generally understand, and well-known functions and configurations that may make the main idea of the present disclosure unclear in the following description and the drawings are not described in detail.

[0048] The present disclosure, in which a femoral nail is fitted in an end of a femoral marrow, a leg screw combined with a cap is laterally inserted in a transverse hole formed at an angle with respect to the longitudinal axis of the nail, and the leg screw is fixed to be longitudinally movable without rotating in the transverse hole, as shown in FIG. 3, is composed of pin guide grooves 101 formed on a leg screw 100, a superelastic member 200, and a cap 300.

[0049] In more detail, the leg screw 100 is formed in the same way as the related art, but is different in that symmetric spiral pin guide grooves 101 are formed on both sides thereof, respectively.

[0050] In addition, the pin guide grooves 101 are formed throughout the body of the leg screw 100 to a threaded portion 110.

[0051] A connecting rod 210 having a thin pin shape is formed at a first end of the superelastic member 200 that is inserted in the pin guide grooves 101, and a pair of elastic pins 211 integrally bends from both ends of the connecting rod 210.

[0052] The superelastic member 200 has pseudoelasticity or superelasticity and uses the property of a shape-memory alloy returning into a preset shape.

[0053] In addition, the cap 300, as shown in FIG. 4c, is thread-fastened to the rear end of the leg screw 100 while pressing the connecting rod 210 of the superelastic member 200.

[0054] Accordingly, a rotation prevention member 1 of a leg screw for fixing a bone having this configuration, as shown in FIG. 6, uses the nail 20 and the leg screw to treat a fracture portion 17 of a medullary cavity 10 in a surgery, which is the same as the related art.

[0055] However, according to the present disclosure, the superelastic member 200 is fitted in the leg screw 100 that is coupled to the nail 20 and fixes the fracture portion 17 in the medullary cavity to prevent the leg screw 100 from rotating.

[0056] In more detail, as shown in FIG. 4A, with the leg screw 100, the superelastic member 200, and the cap 300 prepared, as shown in FIG. 4B, the superelastic member 200 is fitted into the pin guide grooves 101 of the leg screw 100, and then assembled, as shown in FIG. 4C.

[0057] Next, as shown in FIG. 6, the leg screw 100 combined with the superelastic member 200 is pushed into the transverse hole 20a formed in the nail 20, thereby being coupled to the fracture portion.

[0058] Accordingly, while the leg screw 100 is fastened to the fracture portion, the superelastic member 200 opens and comes in close contact with the fracture portion due to elasticity.

[0059] Accordingly, the superelastic member 200 firmly presses the leg screw 100, thereby being able to prevent rotation of the leg screw.

[0060] Further, although the configuration and rotation of a rotation prevention member of a leg screw for fixing a bone of the present disclosure were described above, the present disclosure may be changed, modified, and replaced in various ways by those skilled in the art, and the change, modification, and replacement should be construed as being included in the protective range of the present disclosure.

DESCRIPTION OF THE REFERENCE NUMERALS

[0061]

TABLE-US-00001 10: leg screw 101: pin guide groove 110: threaded portion 200: superelastic member 210: connecting rod 211, 211: elastic member 300: cap