CN2478561Y

CN2478561Y - Pressure intramedullary nail

Info

Publication number: CN2478561Y
Application number: CN 01222202
Authority: CN
Inventors: 林正洪
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-04-27
Filing date: 2001-04-27
Publication date: 2002-02-27
Anticipated expiration: 2011-04-27

Abstract

The utility model relates to a pressor intramedullary pin, which is used for treating the fracture of middle lower parts of a thighbonem, a shank bone and a shoulder bone, in particular to a comminuted fracture, and is a hollow pin body 1; wherein, a cross lock hole 2 is arranged on an upper end of the pin body, and a oblong pressor hole 3 is positioned on a lower end. The radius of an upper semicircle 3-1 of the oblong hole is larger than the radius of a lower semicircle 3-2. The hole wall is provided with a screw pitch convex 3-3, which is smaller than the oblong hole and applicable to the screw pitch of a tapping screw. The pressor intramedullary pin is reasonably designed. The stress sheltering problem is solved. The compression can be continued and the contact of the broken ends of fractured bone is more close and stable, so that the disunion rate of bones or the slow disunion rate can be reduced and the union is fast.

Description

Compress intramedullary nail

This utility model relates to a kind of surgical medical equipment, mainly is a kind of compress intramedullary nail, is used for the treatment of hypomere fracture, especially comminuted fracture in femur, tibia, the humerus.

The intramedullary pin utility ratio of the long bone fracture of state such as America and Europe treatment in recent years reaches more than 90%.Because existing intramedullary pin itself does not possess the function that epiphysis is moved, make the broken ends of fractured bone can't obtain pressurization, thereby make some comminuted degree seriously reach damaged more bone stump and can not closely contact the steadiness that has influenced the broken ends of fractured bone, cause nonunion or slow concrescence easily.Chinese patent literature CN2293297Y " self-pressurization intramedullary pin " discloses a kind of intramedullary pin, and it is a hollow spike body, and nail body upper end has interlocking hole, lower end that Long Circle pressurization hole is arranged, and chamfering is arranged at top, hole.When the action of compressive stress of health on hold-down screw because screw moves down the space in the Long Circle hole, compressive stress can be acted on the fracture site by the backbone, with healing acceleration.Because a certain special body position that compressive stress relied on of this intramedullary pin is that the patient is difficult to adhere to for a long time,, make treatment be subjected to very big influence so whenever Body Position Change, compressive stress changes or disappears thereupon.

The purpose of this utility model is in order to overcome the deficiency of above-mentioned prior art, to provide a kind of not receptor site influence, the intramedullary pin of persistent pressure.

This utility model is achieved through the following technical solutions.The intramedullary pin of this pressurization, it is a nail body, there is the interlocking hole nail body upper end, there is Long Circle pressurization hole the lower end, first radius of a circle that it is characterized in that described Long Circle hole is greater than second radius of a circle, and hole wall has one less than Long Circle hole and the pitch protruding (playing the effect of female thread) that adapts with tapping screw pitch.For make things convenient for screw from the front or reverse side be screwed into, pitch is protruding can be located at the bottom of the hole or hole face; Or be located in the middle part of the hole.Two Long Circle holes can make bone fixation get better on the nail body.

Compress intramedullary nail simplicity of design of the present utility model is reasonable, has solved the stress shielding problem, and pressurization continues, and broken ends of fractured bone contact is tightr more stable, reduces nonunion or slow concrescence rate, makes union of fracture faster.

Fig. 1 is a sketch map of the present utility model;

Fig. 2 is this practicality pressurization hole sketch map;

Fig. 3 is the protruding A-A cutaway view at the bottom of the hole of Fig. 2 pitch;

Fig. 4 is the protruding A-A cutaway view at the middle part, hole of Fig. 2 pitch.

Below in conjunction with embodiment and accompanying drawing this utility model is further described.See Fig. 1, compress intramedullary nail is a high-strength stainless steel nail body 1, nail body diameter 9mm, and generally long 285～380mm, the long 290mm of this example (owing to be provided with the Long Circle hole, so than about the short 10mm of same specification intramedullary pin).There are 2 interlocking holes 2 up and down nail body upper end, and there are 2 Long Circle pressurization holes 3 lower end; The long 10.0mm in hole, Long Circle hole, the radius 2.25mm of its upper semi-circle 3-1 is greater than the radius 2.0mm (see figure 2) of lower half circle 3-2.Hole wall have one less than the Long Circle hole and with the protruding 3-3 of pitch that tapping screw pitch adapts, two kinds of structures can be arranged: the one, pitch is protruding at the bottom of the hole (or hole face, see Fig. 3), the 2nd, in middle part, hole (see figure 4).The protruding height 2mm of this routine pitch plays the effect of female thread.Tapping screw diameter head is more bigger than afterbody, generally long 20～50mm; The long 35mm of this example, head diameter 4.0mm, tail diameter 3.5mm.During use, screw is positioned lower half circle 3-2 earlier, and in turning, the diameter of screw is cumulative, and the screw centrage is gradually drawn close to upper semi-circle, that is it is tightr more stable to drive the fixed knochenbruch end in contact of screw institute, gets final product when being screwed to required compressive stress.

Claims

1, a kind of compress intramedullary nail, a nail body (1) is arranged, there is interlocking hole (2) nail body upper end, there is Long Circle pressurization hole (3) lower end, the radius of upper semi-circle (3-1) that it is characterized in that described Long Circle hole is greater than the radius of lower half circle (3-2), and hole wall has one less than Long Circle hole and the pitch protruding (3-3) that adapts with tapping screw pitch.

2, compress intramedullary nail as claimed in claim 1 is characterized in that described pitch protruding (3-3) is at the bottom of the hole or the face of hole.

3, compress intramedullary nail as claimed in claim 1 is characterized in that described pitch protruding (3-3) is at the middle part, hole

4,, it is characterized in that described Long Circle pressurization hole (3) is two as claim 1 or 2 or 3 described compress intramedullary nails.