DE102005039854B4 - Proximal femoral nail - Google Patents

Abstract

Proximal femoral nail (1) having a self-tapping femoral neck screw (5) received in a bore (4) and a locking pin (8) insertable at the proximal end in the direction of the nail head and at least one locking bore provided at the distal end,
characterized in that
the carrying screw (5) has a passage slot (9) extending over a longitudinal section and an end of the carrying screw (5) opposite the self-tapping thread (12) which has a threaded bore (7) extending in the longitudinal axis direction for receiving a compression screw (14) with one of the threaded bores (7) has complementary external thread,
the bore for receiving the locking pin (8) in Nagelkopflängsrichtung is guided over the area for receiving the support screw (5), wherein the locking pin (8) penetrates the through slot (9) in the inserted state and thereby causes a rotational securing of the support screw (5) , wherein with the actuation of the compression screw (14) this comes into abutment with the in the passage slot (9) located part of the locking pin (8), so that a relative movement between the femoral neck support screw (5) and femur nail (1) can be generated ...

Description

The The invention relates to a proximal femoral nail with in a bore recorded self-tapping femoral neck screw and a at the proximal end in Nagelkopflängsrichtung deployable locking pin and at least one at the distal End provided locking hole.

proximal femoral nails belong for stabilizing pertrochanteric, intertrochanteric or high subtrochanteric Fractures to the state of the art. Known femoral nails have a proximal one End with larger diameter and a distal nail end, which have some flexibility can to minimize stress concentrations. Also, it is already known that the femur nail expediently an angle adapted to the anatomy of, for example, 6 ° about the longitudinal axis has.

Of the Head of known femoral nails is locked by a screw, which at the same time able is a self-tapping hip screw in the nail to secure against rotation or displacement. A correspondingly large inner bore takes the femoral neck screw necessary to stabilize the fracture which is normally self-tapping. The hip slide provides with respect to the femoral neck screw a rotation lock dar. Usually the femoral neck screws still have a slip-through protection on.

At the Distal nail end holes are inserted, which are the recording serve at least one locking bolt. The above briefly explained Femoral nail becomes operative as possible deep into the femoral opening introduced, in which case then an introduction of the Hüftgleitschraube and the femoral neck screw with the aid of drilling templates is made. This introduction is done by using Guidewires, with direction and position over suitable image rendering technique during the execution of this operational step is controlled. After a determination the lengths the hip slide and femoral neck screw, these are using a special key screwed. For the case that compression of the fracture is required exists in known solutions the possibility, on the aiming arm to provide a compression nut. With the help of this compression nut can then over the femoral neck screw will compress the fracture. After losing weight of the aiming arm However, in these known nails compression is not more is possible. The explained state the technology goes back on the offered and sold by Synthes AG PFN Femurnagel (see www.synthes.com).

After the femur nail DE 198 29 228 C1 , Tradename TARGON PF, manufactured and sold by the company Aeskulap, consists of the intramedullary nail, a carrier screw and a carrier sleeve into which the carrier screw can telescope. In addition, another screw is provided which blocks unwanted rotation of the femoral neck screw. The femoral neck screw can slide in this variant of the prior art in intramedullary nail in its longitudinal direction, which should allow sintering of the fracture.

It However, this is not without additional in this femoral nail design Application of special target devices possible, to effect a defined compression of the fracture.

Another known bone nail for intramedullary compression nailing of femur fractures is in DE 198 52 945 A1 shown. There, a compression sleeve is inserted into an angular bore of the intramedullary nail in order to guide a pull screw non-rotatably.

The locking nail for the treatment of fractures of the proximal femur DE 92 00 328 U1 is particularly suitable for the treatment of subcapital fractures. For this purpose, the proximal slanted passage of the nail shank has a larger diameter than the associated femoral neck screw. The proximal oblique bore is formed in an axis transverse to the nail axis as a slot to pivot the recorded femoral neck screw limited in the oblique bore and thus to be able to orient.

To further the technology is still on the German utility model DE 86 20 399 U1 , WO 02/098330 A2 and US 2001/0034523 A1 alerted.

Out The above, it is therefore an object of the invention, an advanced proximal femoral nail with self-tapping taken in a bore Specify femoral neck screw, said femur nail for one the possibility an integral compression of the fracture and on the other hand the possibility there is a simple way to effect a rotation backup, and without a separate Hüftgleitschraube with additional Bore in the bone must be provided.

The solution The object of the invention is carried out with a proximal femoral nail according to the combination of features according to claim 1, wherein the dependent claims at least expedient embodiments and represent further education.

at has the femoral nail according to the invention the mounting screw over a longitudinal section extending through slot. On the self-tapping thread opposite end the support screw has this one extending in the longitudinal axis direction Tapped hole for receiving a compression screw with one of the Complementary threaded hole External thread.

The Bore for receiving the locking pin is in Nagelkopflängsrichtung to about guided the area for receiving the support screw, wherein the locking pin in the inserted state penetrates the through slot and thereby a rotation of the backing screw causes.

With pressing the compression screw comes into abutment with the one in the passage slot located part of the locking pin, so that a relative movement between femoral neck screw and femoral nail in the sense of compression can be achieved.

Of the Femoral nail according to the invention has in an advantageous embodiment of the invention a continuous bore.

As well drilled through is the support screw.

At the end of the support screw, which is the recording of the compression screw serves, the support screw has a slope.

Of the Locking pin is designed as a pin with tapered tip and stepped Diameters executed, being in the area of the external thread a blind hole with polygon for holding a tool, e.g. a hexagon wrench is trained.

Prefers the compression screw is designed as a grub screw. By a provided at the distal end slot as a locking hole there is a dynamic lock, i. the femur nail can still gliding in the distal direction for a given area, before it rests on the distal locking screw.

application point The femoral nail is inserted proximally into the medullary cavity of the femur. hereafter The screw is screwed through the nail in the femoral head and aligned so that the taper of the screw parallel to Axis of the nail head runs. Therefor a special screwdriver is used.

Subsequently, will the locking pin in the longitudinal direction of the nail through the slot of the support screw screwed into the nail. With the introduction of the safety pin is on the one hand, the support screw secured against rotation. On the other hand, the sliding path of the support screw in the nail on the length of the passage slot limited. An emigration from the nail is excluded. The carrying screw remains dynamic, i. movable, causing the perforation of the femoral head during sintering of the fracture zone is effectively prevented.

A desired Intraoperative compression of the fracture gap can be achieved with the help of Compression screw done, which is supported on the locking pin. Of the desired Compression pressure remains according to the position of the compression screw receive.

In an embodiment of the invention has the support screw in the area their oblique a groove of predetermined depth, into which the insertion instrument according to Art a screwdriver is used and guided.

The Invention will be described below with reference to an embodiment and below With the help of figures closer explained become.

in this connection demonstrate:

1 different views of the proximal femoral nail;

2 Side view and sectional view of the self-tapping femoral neck support screw;

3 a view of the locking pin;

4 a representation of the compression screw;

5 a representation of the femoral nail with already introduced Tragschraube;

6 a representation of the proximal femoral nail with screw and impending introduction of the safety pin and

7 a representation of the proximal femoral nail with support screw, inserted locking pin and impending screwing the compression screw in the associated internal threaded portion of the support screw.

The proximal femoral nail 1 According to the figurative representations has a the anatomical conditions of the femur corresponding bend or curvature 2 on.

In the lower part of the femur nail 1 is a hole for distal locking, when off exemplary embodiment in the form of a slot 3 brought in.

In the nail head area there is another hole 4 , which is the inclusion of a femoral neck screw 5 serves.

The angle of the bore 4 to the longitudinal axis of the nail 1 is also chosen according to the anatomical conditions.

The femoral nail according to the picture according to 1 has a through hole 6 ,

At the proximal end of the femoral nail 1 is another hole 7 introduced with internal thread. This hole 7 with internal thread serves to receive a safety pin 8th (please refer 3 ).

As in particular from the 1 . 6 and 7 The hole is visible 7 for receiving the safety pin 8th in Nagelkopflängsrichtung to over the range of the recording of the support screw 5 guided, with the locking pin 8th in the inserted state, the passage slot 9 penetrates inside the bearing screw.

Above the hole 7 with internal thread is a blind hole 10 , also located with an internal thread, which serves to receive a locking screw, not shown.

The internal thread of the bore 7 does not have to extend over the entire bore length, but only over a partial area, in particular preferably towards the proximal end.

The carrying screw according to 2 has the mentioned passage slot 9 , a through hole 11 and an end with self-tapping thread 12 ,

On the self-tapping thread 12 opposite end of the support screw 5 is a threaded bore extending in the longitudinal axis direction 13 introduced, the inclusion of a compression screw 14 (please refer 4 ) serves.

The self-tapping thread 12 opposite end of the support screw 5 has a slope 15 on.

In the area of the slope 15 is a groove 16 introduced, which serves to receive a special screwing tool (not shown).

The locking pin 8th according to 3 has a substantially pin shape with conical tip 17 on.

Over the length of the locking pin 8th have a stepped diameter.

In the area of external thread 18 of the safety pin 8th is a blind hole with Innenvielkant 19 introduced, and indeed for receiving a tool, in particular in the form of a hexagon socket wrench.

The compression screw 14 according to 4 preferably has a grub screw shape and also has a blind hole with inner polygon 20 for receiving a screwing tool.

5 shows how the femoral neck screw 5 into the hole 4 of the femur nail 1 was introduced. After the femoral neck screw 5 screwed into the femoral head, not shown, and was aligned so that the beveled end 15 runs substantially parallel to the nail head, the insertion of the locking pin takes place 8th via the associated hole 7 in the nail 1 ,

With the introduction of the safety pin 8th on the one hand, the femoral neck screw 5 secured against rotation. On the other hand, the sliding path of the support screw 5 to the length of the passage slot 9 limited. An emigration from the nail is excluded.

The carrying screw 5 remains movable, whereby the perforation of the femoral head during sintering of the fracture zone and the associated shortening of the bone during healing can be prevented.

After according to 7 the locking pin 8th in the hole of the nail 1 was introduced, the compression screw 14 into the threaded hole 13 used. The desired intraoperative compression of the fracture gap is achieved using the compression screw 14 who are at the security pin 8th supports, secured.

In summary causes the locking pin in conjunction with the transverse slot or the through slot in the support screw a rotation lock, further wherein a sliding path of the support screw in accordance with Length of the Passage slot is maintained.

With In addition, it is possible to use the compression screw one To achieve relative movement between the propeller and nail, taking the compression screw on the locking pin, which is already screwed is supported.

1

Femoral Nail

2

curvature

3

Long hole

4

drilling

5

Femoral neck support screw

6

drilling in the nail

7

drilling with internal thread

8th

safety pin

9

Through slot

10

blind with internal thread

11

drilling the carrying screw

12

Self-tapping thread

13

threaded hole

14

compression screw

15

slope

16

groove

17

conical top

18

external thread

19 20

Internal polygon

Claims (7)

Proximal Femoral Nail ( 1 ) with in a bore ( 4 ) self-tapping femoral neck screw ( 5 ) and an insertable at the proximal end in Nagelkopflängsrichtung locking pin ( 8th ) and at least one locking hole provided at the distal end, characterized in that the carrying screw ( 5 ) has a longitudinal slot extending passageway ( 9 ) and on the self-tapping thread ( 12 ) opposite end of the support screw ( 5 ) this one extending in the longitudinal axis threaded bore ( 7 ) for receiving a compression screw ( 14 ) with one of the threaded holes ( 7 ) has complementary external thread, the bore for receiving the locking pin ( 8th ) in Nagelkopflängsrichtung to beyond the area for receiving the support screw ( 5 ) is guided, wherein the locking pin ( 8th ) in the inserted state, the passage slot ( 9 ) penetrates and thereby a rotation lock of the support screw ( 5 ), whereby with the actuation of the compression screw ( 14 ) in abutment with the one in the passage slot ( 9 ) located part of the safety pin ( 8th ), so that a relative movement between the femoral neck screw ( 5 ) and femoral nail ( 1 ) is producible. Femoral nail according to claim 1, characterized in that this in the nail head longitudinal direction extending bore ( 6 ) having. Femoral nail according to claim 1 or 2, characterized in that the support screw ( 5 ) a through hole ( 11 ) owns. Femoral nail according to one of the preceding claims, characterized in that the bearing screw ( 5 ) at the end for receiving the compression screw ( 14 ) a slope ( 15 ) having. Femoral nail according to one of the preceding claims, characterized in that the locking pin ( 8th ) a conical tip ( 17 ) and stepped diameter, wherein in the region of the external thread ( 18 ) a blind hole bore with Innenvielkant ( 19 ; 20 ) is formed for receiving a tool. Femoral nail according to one of the preceding claims, characterized in that the compression screw ( 14 ) is designed as a grub screw. Femoral nail according to one of the preceding claims, characterized in that the locking hole provided at the distal end is designed as a slot ( 3 ) is trained.