CN201701289U

CN201701289U - Lag screw

Info

Publication number: CN201701289U
Application number: CN2010201678847U
Authority: CN
Inventors: 于圣泰; 蔡勇
Original assignee: Trauson Medical Instrument China Co Ltd
Priority date: 2010-04-23
Filing date: 2010-04-23
Publication date: 2011-01-12
Anticipated expiration: 2020-04-23

Abstract

The utility model discloses a lag screw, which comprises a screw body, a screw casing, a screw lock latch and a screw lock sleeve. The screw casing is coated at the rear end of the screw body, the screw lock latch is connected to the rear end of the screw body, the screw lock sleeve is fixedly connected with the tail of the screw casing and is in threaded connection with the screw lock latch, the screw body is provided with a circular through hole axially, a spiral blade is arranged on the surface of the front end of the screw body, the diameter of the rear end of the screw body is smaller than that of the front end of the screw body, the screw lock latch is axially provided with a through hole, the rear end of the screw lock latch is hexagonal, the surface of the screw lock latch is provided with external thread, the screw lock sleeve is provided with a threaded through hole axially, and the threaded through hole matches with the external thread of the screw lock latch. By aid of the structure, anchoring force of the blade to bones is increased, wound caused by the blade is small, and the blade has high cutting resistance, is fixed firmly and reliably and can effectively prevent bone rotating or sinking.

Description

Lag screw

Technical field

This utility model relates to lag screw.

Background technology

In the surgical operation of treatment fracture; usually can use intramedullary pin and fix fracture site; intramedullary pin needs lag screw to be fixed on the human skeleton; the front end of present lag screw adopts the screw-type structure usually; when physical activity; capital movement tendency is to want to shake off out hanging tight of lag screw; be that lag screw has the trend that withdraws from the femoral head; simultaneously for the old people; old people's sclerotin is comparatively loose; and the anti-power of cutting out of screw-type structure is less, and the pressure that in squeezing into the process of skeleton skeleton is formed is less, so lag screw is installed, and the back is easy becomes flexible.

The utility model content

The purpose of this utility model is to provide lag screw, and is simple in structure, and surgical injury is little, safety simple to operate, and the fixation of lag screw is reliable.

The technical scheme that realizes this utility model purpose is: lag screw, comprise screw body, screw overcoat, screw snap close and screw lock tube, the screw overcoat is enclosed within the rear end of screw body, the screw snap close is connected with the rear end of screw body, the screw lock tube is fixedlyed connected with the afterbody of screw overcoat, and is threaded with the screw snap close; Described screw body be axially arranged with manhole, front end is provided with spiral blade, the diameter of rear end is less than the diameter of front end; Described screw snap close be axially arranged with the hole, the hole is a through hole, and the rear end is hexagonal hole, the screw catch surface is provided with external screw thread; Described screw lock tube be axially arranged with tapped through hole, tapped through hole cooperates with the external screw thread of screw snap close.

The afterbody of described screw body is provided with U type groove, and the bottom land of U type groove is the outer wall of screw body, and the rear end of U type groove is provided with the nib to inner process; The axial cross section of the front end of described screw snap close is I-shaped, and screw snap close front end cooperates with the U type groove and the nib of screw body, is connected the rear end of screw body.

The vertical cross-section of the axle of described screw overcoat is non-circular.

The inside of the tail end of described screw overcoat is provided with convex, and the front end of screw lock tube is provided with grab, and grab is connected on the convex of screw overcoat.

The spiral blade of described screw body is a backpitch; The screw thread of the tapped through hole of the external screw thread of described screw snap close and screw lock tube is left-hand thread.

The end face of the tail end of the U type groove of described screw body is the flank of tooth, and the front end face of screw lock tube is provided with equally distributed tooth, and the tooth and the flank of tooth can closely cooperate.

The utlity model has following beneficial effect: the front end of (1) screw body of the present utility model is provided with spiral blade, this structure has improved blade and has made a concerted effort for the anchor of skeleton, and the wound that causes is little, the anti-power of the cutting out height of blade, the fixation of blade is reliable, can effectively prevent bone rotation and sinking.

(2) screw body of the present utility model be axially arranged with manhole, this structure can play decompressing effect, increase effective blood confession of bone, and surgical injury is little, goes out insufficiency of blood, the healing rate height.

(3) this utility model screw lock tube is fixedlyed connected with the afterbody of screw overcoat, and is threaded with the screw snap close, and this structure makes the adjustable length of lag screw can adapt to the fixing of different parts or different the wounded's skeletons.

(4) screw snap close front end of the present utility model cooperates with the U type groove and the nib of screw body, be connected the rear end of screw body, this structure makes when screw latches in screw lock tube internal rotation that screw body can not followed the screw snap close and be rotated, and can not cause incompatible sense with the wounded.

(7) vertical cross-section of the axle of screw overcoat of the present utility model is non-circular, and after this structure made that lag screw is locked, the screw overcoat can not rotate, and structure is more stable.

(6) the spiral blade of screw body of the present utility model is a backpitch, the screw thread of the tapped through hole of the external screw thread of screw snap close and screw lock tube also is a left-hand thread, this structure makes that squeezing into behind the skeleton of blade is more stable, and after in the hexagonal hole of lag screw driver insertion screw snap close rear end, only need turn clockwise, just can be with screw snap close and the locking of screw lock tube, being rotated counterclockwise both will separate, and so just meets the custom of tightening thing in people's daily life clockwise.

(7) end face of the tail end of the U type groove of screw body of the present utility model is the flank of tooth, the front end face of screw lock tube is provided with equally distributed tooth, and the tooth and the flank of tooth can closely cooperate, and this structure makes after the lag screw locking, screw body and screw lock tube can closely be interlocked, and are not easy to become flexible.

Description of drawings

For the easier quilt of content of the present utility model is clearly understood, according to specific embodiment also in conjunction with the accompanying drawings, this utility model is described in further detail, wherein below

Structural representation when Fig. 1 locks for this utility model screw snap close and screw lock tube.

Structural representation when Fig. 2 unclamps for this utility model screw snap close and screw lock tube.

Fig. 3 is the structural representation of this utility model screw body.

Fig. 4 is the vertical view of Fig. 3.

Fig. 5 is the upward view of Fig. 3.

Fig. 6 is the structural representation of this utility model screw overcoat.

Fig. 7 is the A place partial enlarged drawing of Fig. 6.

Fig. 8 is the vertical view of Fig. 6.

Fig. 9 is the structural representation of this utility model screw snap close.

Figure 10 is the structural representation of this utility model screw lock tube.

Figure 11 is the left view of Figure 10.

Label is in the accompanying drawing:

Screw body 1, manhole 11, spiral blade 12, U type groove 13, nib 14, the flank of tooth 15, screw overcoat 2, convex 21, screw snap close 3, hole 31, external screw thread 32, screw lock tube 4, tapped through hole 41, grab 42, tooth 43.

The specific embodiment

(embodiment 1)

See Fig. 1 to Figure 11, present embodiment comprises screw body 1, screw overcoat 2, screw snap close 3 and screw lock tube 4.

Screw body 1 be axially arranged with manhole 11, front end is provided with spiral blade 12, spiral blade 12 is a backpitch, the diameter of rear end is less than the diameter of front end, the afterbody of screw body 1 is provided with U type groove 13, the bottom land of U type groove 13 is the outer wall of screw body 1, and the rear end of U type groove 13 is provided with the nib 14 to inner process, and the end face of the tail end of the U type groove 13 of screw body 1 is the flank of tooth 15.The vertical cross-section of the axle of screw overcoat 2 is non-circular, and screw overcoat 2 is enclosed within the rear end of screw body 1, and the inside of tail end is provided with convex 21.Screw snap close 3 be axially arranged with hole 31, hole 31 is a through hole, and the rear end is a hexagonal hole, screw snap close 3 surfaces are provided with external screw thread 32, the axial cross section of the front end of screw snap close 3 is I-shaped, screw snap close 3 front ends cooperate with the U type groove 13 and the nib 14 of screw body 1, are connected the rear end of screw body 1.Screw lock tube 4 is fixedlyed connected with the afterbody of screw overcoat 2, and be threaded with screw snap close 3, screw lock tube 4 be axially arranged with tapped through hole 41, tapped through hole 41 cooperates with the external screw thread 32 of screw snap close 3 and both are left-hand thread, the front end of screw lock tube 4 is provided with grab 42, grab 42 is connected on the convex 21 of screw overcoat 2, and the front end face of screw lock tube 4 is provided with equally distributed tooth 43, and tooth 43 can closely cooperate with the flank of tooth 15.

Should be appreciated that specific embodiment described above only is used to explain this utility model, and be not used in qualification this utility model.Conspicuous variation of being extended out by spirit of the present utility model or change still are among the protection domain of the present utility model.

Claims

1. lag screw, it is characterized in that: comprise screw body (1), screw overcoat (2), screw snap close (3) and screw lock tube (4), screw overcoat (2) is enclosed within the rear end of screw body (1), screw snap close (3) is connected with the rear end of screw body (1), screw lock tube (4) is fixedlyed connected with the afterbody of screw overcoat (2), and is threaded with screw snap close (3); Described screw body (1) be axially arranged with manhole (11), front end is provided with spiral blade (12), the diameter of rear end is less than the diameter of front end; Described screw snap close (3) be axially arranged with hole (31), hole (31) are through hole, and the rear end is hexagonal hole, screw snap close (3) surface is provided with external screw thread (32); Described screw lock tube (4) be axially arranged with tapped through hole (41), tapped through hole (41) cooperates with the external screw thread (32) of screw snap close (3).

2. lag screw according to claim 1 is characterized in that: the afterbody of described screw body (1) is provided with U type groove (13), and the bottom land of U type groove (13) is the outer wall of screw body (1), and the rear end of U type groove (13) is provided with the nib (14) to inner process; The axial cross section of the front end of described screw snap close (3) is I-shaped, and screw snap close (3) front end cooperates with the U type groove (13) and the nib (14) of screw body (1), is connected the rear end of screw body (1).

3. lag screw according to claim 2 is characterized in that: the vertical cross-section of the axle of described screw overcoat (2) is non-circular.

4. lag screw according to claim 3 is characterized in that: the inside of the tail end of described screw overcoat (2) is provided with convex (21), and the front end of screw lock tube (4) is provided with grab (42), and grab (42) is connected on the convex (21) of screw overcoat (2).

5. lag screw according to claim 4 is characterized in that: the spiral blade (12) of described screw body (1) is a backpitch; The external screw thread (32) of described screw snap close (3) is left-hand thread with the screw thread of the tapped through hole (41) of screw lock tube (4).

6. lag screw according to claim 5, it is characterized in that: the end face of the tail end of the U type groove (13) of described screw body (1) is the flank of tooth (15), the front end face of screw lock tube (4) is provided with equally distributed tooth (43), and tooth (43) can closely cooperate with the flank of tooth (15).