EP2408387A1

EP2408387A1 - Dorsal nail plate

Info

Publication number: EP2408387A1
Application number: EP10713319A
Authority: EP
Inventors: Klaus Buhl
Original assignee: Mondeal Medical Systems GmbH
Current assignee: Mondeal Medical Systems GmbH
Priority date: 2009-03-20
Filing date: 2010-03-18
Publication date: 2012-01-25
Also published as: DE102009001707A1; WO2010106139A1

Abstract

The present invention relates to a fastening plate (1) for bones having a plate-like head region (2) for attaching to a broken bone region having a plurality of perforations (11, 12) for receiving fastening means (13) and an intramedullary shaft region (8) for arrangement in the bone, wherein the shaft region and head region are connected to one another and wherein the shaft region has a curved section along the longitudinal axis at least on the end turned away from the head region, and a corresponding operation set having a fastening plate of this kind and a target device (15) for attaching anchoring screws.

Description

DORSALE NAIL PLATE

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The present invention relates to a bone fixation plate having a plate-like head portion for engaging a broken bone portion having a plurality of apertures for receiving fixation means and an intramedullary shaft portion for placement in bone, wherein the shaft portion and head portion are connected to each other. The invention further relates to a corresponding operation set with a Zielgerat for the arrangement of the fixation plate in the human body

STATE OF THE ART

For the treatment of bone fractures, in particular in the area of the wrist, it is known to provide fixation plates which are temporarily arranged as an implant in the human body in the region of the bones in order to fix the bone fragments until they have healed again by mutually growing together. In this connection it is also known For example, use dorsal nail plates in fractures in the wrist, with corresponding dorsal nail plates according to the prior art have a T-shaped structure with a plate-shaped head portion and a shaft portion, as disclosed for example in WO 03/020007 A2

It is also known from the prior art to form such dorsal nail plates or fixation plates such that the shaft region, which is designed as an elongated rod, is arranged in the bone marrow canal of the spoke, while the head region is arranged on the outside of the fractured bone region in order to provide different fixation means which fix the fragments of the fracture between the outer head region, which is usually plate-shaped, and the intramedullary bone

Shank, which is formed as an elongated rod, a side-view S-shaped connection area is provided, which is guided through an opening in the bone, on the one hand to the outside of the plate-shaped head portion of the bone and the intramedullary arrangement of the shaft in the bone enable In such an embodiment, however, there is the problem that the implant, which is only temporarily in the body, is difficult to remove upon removal after healing of the fracture, and injury to the bone area occurs during removal in which the fixation plate is inserted into the bone so that after removal of the fixation plate, a further, longer healing process becomes necessary.

DISCLOSURE OF THE INVENTION

OBJECT OF THE INVENTION

It is therefore an object of the present invention to provide a fixation plate which makes it possible to easily remove the fixation plate after the healing of the fracture. At the same time, however, the fixation plate should not have any worse properties than the known fixation plates and in particular enable a safe and positionally stable arrangement in or on the bone and fixation of the bone fragments. In addition, the fixation plate should be simple and easy to manufacture. In addition, it should be easy to handle for the surgeon overall, so even when inserting.

TECHNICAL SOLUTION

This object is achieved by a fixing plate with the features of claim 1 and an operation set with the features of claim 15. Advantageous embodiments are the subject of the dependent claims.

The invention is characterized in that the shaft region is not designed as a straight, elongated rod as in the prior art, but at its end remote from the head region (free end) has at least one curved portion. By the curved portion, it is possible to remove the shaft in the removal of the fixation plate after healing of the fracture in a simple manner from the bone marrow canal by unscrewing.

Accordingly, the curved portion of the shaft portion along the longitudinal axis of the fixing plate is curved, ie along the direction, ie in the direction of its longest Extension or in the direction in which the shaft is inserted into the intramedullary canal of the bone.

The curved section can extend over the entire shaft region, ie over the entire longitudinal extension of the shaft region, or only affect parts thereof.

In addition, the curvature can be the same in particular with regard to the radius of curvature along the entire curvature section or for all curvature sections, or the curvature can be different within the curvature section or in different curvature sections, in particular with regard to the curvature radius.

In addition to the radius of curvature, the curvature can also differ with regard to the length of the curvature section in the different curvature sections. In particular, curvatures with different signs, ie with respect to the direction of curvature, can also be present in the curvature sections. Accordingly, concave and convex curvature sections may alternate.

The curvature portions may refer to portions in the longitudinal extent of the intramedullary shaft region, i. H. that curved or non-curved regions may be present along the longitudinal axis.

In addition, however, it is also possible that the curvature sections relate to the top and bottom of the fixing plate and, for example, only the bottom, that is, the side facing away from the head portion of the shaft is curved, while the top is not curved or has other curvature portions. In particular, the curvatures at the bottom and top can also be different, for example, in terms of radius of curvature, length and number of curved sections, etc.

According to a simple embodiment, the shaft may be formed as a curved rod with a constant radius of curvature, wherein the curvature may be concave, in particular on the upper side facing the head area and convex on the underside facing away from the head area. The intramedullary shaft may be formed by a rod of any cross-section, such as square, rectangular, round, oval or polygonal cross-section.

The rod may be cross-sectionally consistent in cross section or may be tapered towards its free end, for example, to facilitate further removal of the intramedullary stem from the bone marrow canal.

On the shaft means may be provided for receiving fastening means, such as continuous or bag-like threaded holes for receiving anchoring screws.

The curved shaft may in particular be arranged on the plate of the head region in the connection region between the head region and the intramedullary shaft of the fixation plate such that an acute angle forms between the plate plane and a tangent to the intramedullary shaft.

The plate-like head region may have an extension which protrudes in the direction of the shaft region over the connecting region of head region and shaft region and serves to rest against the bone wall in order to allow a secure and firm attachment of the fixation plate.

The fixation plate may be formed in particular as a dorsal nail plate for the dorsal fixation in wrist fractures, wherein the fixing means for fixing the fragments, which are arranged on the fixing plate are not limited to nails, but also screws, pins and other suitable fixing means and combinations thereof can. However, the invention is not limited to the use of the fixation plate as a dorsal nail plate, but includes the use in all bone fractures in which the fixation plate can be used with the fiction, contemporary design.

The fixation plate can also comprise positioning and connecting means for a target device, which make it possible to fix a target device in a defined orientation stably and securely with the fixation device. connecting plate to bring about anchoring means and / or fixing means on the Zielgerat

The invention thus also includes an operation set comprising a fixation plate according to the invention and a corresponding target device

BRIEF DESCRIPTION OF THE FIGURES

Further advantages, characteristics and features of the present invention will become apparent from the description of an exemplary embodiment with reference to the accompanying drawings. The drawings show in a purely schematic manner in FIG

FIG. 1 shows a side view of a fixing plate according to the invention with a target device arranged thereon, FIG. 2 shows a perspective view of the fixing plate with target device from FIG

1 ,

FIG. 3 shows a side view of the fixing plate and the target device from FIGS. 1 and 2 when arranged in or on a bone,

FIG. 4 shows a side view of a sleeve and drilling arrangement for the introduction of anchoring screws over the target device,

Figure 5 is a plan view of a fixing plate on a partially shown

Bone,

6 shows a side view of a fixation plate fastened in or on a bone, and FIG. 7 shows a representation of the angular distribution of the fixation screws

exemplary

FIG. 1 shows a side view of an inventive surgical set comprising a fixation plate 1 for placement in a human body and a target device 15, which helps the surgeon to place the fixation plate 1 in or on a bone. The fixation plate 1 comprises a plate-like or plate-shaped head region 2 a curved shaft 8 arranged as an intramedullary portion of the fixation plate 1 in the bone marrow canal of a bone, while the plate-like head portion 2 rests on the outside in the region of a broken bone in order to fix the bone fragments located there via fixation means 13, such as nails, pins or screws.

Correspondingly, the head region 2 or the plate 6 of the head region 2 openings 11, 12, in which the fixing means 13 in the form of pins, nails, screws or the like can be accommodated. The apertures 11 may be formed as continuous threaded openings, for example, to receive screws therein, or as simple sleeves for receiving nails or the like. The openings 11, 12 may be arranged in different orientations in the plate of the head region 2 in order to hold the fixing means 13 in certain orientations. The orientation can be fixed by the opening 11, 12 or the opening 11, 12 may be formed so that it specifies a certain orientation, but introduced the fixing means 13, for example by a self-tapping thread in an at least certain extent in any orientation can be so that the surgeon can respond to the individual circumstances when attaching the fixative.

In the plate-like head portion 2, a plurality of openings may be provided to allow a plurality of fixing means 13 for fixing, for example, a plurality of fragments or to hold a fragment safely by a plurality of differently oriented fixing means.

The fixing means 13, as shown in the embodiment of Figure 1, have a screw head with, for example, a hexagon socket or the like to allow the surgeon easy insertion and removal of the fixing means 13, for example by screwing and unscrewing.

In addition to the fixing elements 13, which can be received in the plate 6 of the head region 2 via the perforations 11 and 12, the plate 6 of the head region 2 also has an opening (not shown) through which a picking wire 14 is inserted into the fixation region of the bone can be determined by means of the spiked wire 14, the orientation of the fixation plate 1 in or on the bone. On the underside of the plate 6 of the head region 2, a curved shaft 8 in the form of a bent rod is arranged in the connection region 3, which is arranged intramedullary in the bone marrow canal of a bone.

The curved rod of the shank region 8 is curved with a radius of curvature which remains constant over its length along the longitudinal extent of the fixing plate 1, that is to say it is curved. H. the shaft 8 represents a part of a circle, wherein the axis of rotation about which the radius must be rotated to form the circle is perpendicular to the image plane of the side view of FIG. The longitudinal extension of the fixing plate results in this case along the cutting edge of the image plane with the plate plane 7 of the head region 2, shown in a dashed line, along which the head region 2 extends. The longitudinal axis is thus given by the shaft 8 and the successive arrangement of head portion 2 and shaft 8.

In the exemplary embodiment shown, the shank 8 is curved in the same way both on the upper side 10 facing the head region 2 and on the underside 9 facing away from the head region, so that a uniform cross-section of the shank 8 over the longitudinal extent results. At the top 10, the curvature is concave, while at the bottom 9, the curvature is convex.

At the free end 4 of the shaft 8 of the curved rod is cut almost parallel to the plate plane 7.

In the connection area 3, in the embodiment shown, the shaft 8 is butt-connected to the plate of the head area 2, ie the curved bar of the shaft 8 is connected directly to the plate-shaped head area 2 without changing the radius of curvature. Alternatively, it is also possible that the shaft 8 in the connection region 3 has a curvature adapted to the head region 2 and thus an altered curvature with respect to the remaining sections of the shaft 8, ie reverses its curvature direction and slides in the manner of an S-shape, for example Plate 6 of the plate-shaped head portion 2 opens (not shown). In both cases, however, assumes a tangent 40 at the curved shaft portion of the connecting portion 3 with the plate plane 7 of the plate 6 of the head portion 2 an acute angle α, ie an angle <90 °. Due to the curvature of the shaft 8, the fixation plate can be easily removed from the bone after healing of the fracture without violating the area in which the shaft 8 is inserted into the bone when the intramedullary shaft 8 is removed , The acute-angled arrangement of the shaft 8 on the plate 6 of the head region 2 also contributes to this.

The plate 6 of the head region 2 has an extension 5, which extends beyond the connection region 3 in the direction of the shaft 8. The extension 5 serves with its underside for abutment against the bone in order to arrange the fixation plate 1 firmly and positionally stable in or on the bone.

The shaft 8 also has two threaded bores 21 and 22, which can be designed as blind holes or as through holes. These threaded holes or openings 21, 22 serve to receive anchoring screws, which firmly connect the shaft 8 with the surrounding bone, as shown in detail in the following drawings.

FIG. 1 also shows a target device 15, which is arranged on the fixing plate 1. For this purpose, the target device 15 has location and connection means, such as the screw 16, of which only the manual operation area can be seen in FIG. The screw 16 is passed through the base body 20 of the target device 15 in order to engage in a threaded bore of the plate 6 of the head region 2 of the fixing plate 1. Accordingly, a firm connection between the target device 15 and the fixing plate 1 can be made with the screw 16. In addition, between the base body 20 and the plate 6 Formschlussele- elements (not shown) may be arranged, which allow an exact alignment and defined position of the base body 20 to the plate 6 and the target device 15 to the fixing plate 1.

Two lateral guide plates 41 and 42 are arranged on the main body 20 in the region of the head region 2, of which only the guide plate 41 can be seen in FIG. 1 (see FIG. 2). The guide plates 41, 42 overlap the plate 6 of the head portion 2 laterally and thus represent corresponding form-fitting elements that allow accurate alignment of the target device 15 to the fixing plate 1. Two Durchgangsoffnungen 25 and 26 (dashed lines) are further provided on the base body 20, which cooperate with corresponding Fuhrungselementen 18, 19 to allow the surgeon on the Durchgangsoffnungen 25, 26 screws in the Knochenmate- πal bring into the threaded holes 21, 22 engage in the shaft 8 In this way, after attachment of the fixation plate 1 with the shaft 8 in the bone marrow canal attachment of the shaft 8 via the threaded bore 21, 22 performed with the surrounding bone in a secure manner

At the top of the main body 20, a holding plate 17 is arranged, which allows the operator to hold the target device 15 and to drive

Between the Fuhrungsplatten 41 and 42, a free space is created, which allows the insertion and removal of a spiked wire 14 in the head portion 2 of the fixing plate 1

The target device 15 also has a base body 20, which makes it possible to arrange the fixing elements 13 in the form of screws, pins, nails, etc. in the plate 6 of the fixing plate 1. This is also clearly visible in particular in the perspective view of FIG FIG. 2 shows the threaded bores 21 and 22 of the shaft 8 in a particularly good manner

FIG. 3 shows the fixation plate 1 and the target device 15 in an arrangement at the place of use. The fixation plate 1 is here arranged with the plate 6 on a bone area 28 in which fragments of a fracture are to be fixed with the fixation means not shown in more detail 8 is arranged in the Knochenmarkska- nal 29 After the fixation plate 1 is arranged in this way on the bone 28 and provisionally fixed on a sprocket 14 or the correct position is determined by means of the screw 16, the target device 15 on the plate 6 and the fixing plate. 1 arranged, wherein a threaded shank of the screw 16 engages in a corresponding threaded bore 27 by means not shown in more detail form-locking elements, the target device 15 is aligned exactly and positionally stable to the fixing plate 1. Accordingly, it is possible over the

Durchgangsoffnungen 25 and 26 in the body 20 of the Zielgerats 15 anchor bolts 23 and 24 introduce, which are inserted through the bone wall 30 into the threaded holes 21 and 22 of the shaft 8 For this purpose, at the Durchgangsoffnungen 25 and 26 of the main body 20 guide members 18, 19, as shown in Figures 1 and 2, are attached.

The guide elements 18, 19 may be formed according to the illustration of Figure 4, namely a first sleeve 31, whose outer diameter corresponds to the diameter of the through holes 25 and 26 in the target device. The inner diameter of the first sleeve corresponds to the diameter of the screw head of the anchoring screws 23 and 24.

In the first sleeve 31, a second sleeve 32 is arranged, whose outer diameter corresponds to the inner diameter of the first sleeve and whose inner diameter corresponds to the thread diameter of the screw plus additionally has a tolerance range, for example in the order of 0.5 to 0.7 mm.

In the second sleeve 32, a sharp rod 33 may be guided as a drilling or pushing member to form a channel in the bone wall 30, which allows the anchoring screws 23 and 24 with its shaft through the bone wall 30 to guide, so that the threaded shaft of the Anchoring screws 23 and 24 can be accommodated in the threaded bores 21 and 22. After the production of a corresponding channel, the second sleeve 32 is removed from the first sleeve 31 in order to be able to insert the anchoring screws 23, 24 through the first sleeve 31.

By anchoring screws 23, 24, the fixing plate 1 is firmly screwed to the bone 28 and the bone wall 30 and fixed in position stable. The fixation means 13 in the form of fixation screws, pins, nails or the like can before and / or after the

Anchoring the fixation plate 1 to the bone wall 30 are introduced with the anchoring screws 23 and 24 in the bone material 28 to fix the fragments of a fracture.

FIGS. 5 and 6 show illustrations of the fixation plate 1 with the fixation means 13 in or on the bone 28. In the top view of FIG. 5, in which the intramedullary shaft 8 is likewise shown as visible, the different orientation of the fixation means 1 is shown in FIG Bone 28 to recognize. In addition, the top sees the recognition of the threaded hole 27 for connecting the target device 15 with the fixing plate 1 and the opening 34 for the arrangement of a spiked wire fourteenth

FIG. 6 shows in a side view the anchoring of the fixing plate 1 with the anchoring screws 23 and 24 and the bone wall 30 as well as again the different orientation of the fretting means 13 on the bone 28

The shaft 8 is, as can be seen easily in the figure 6, arranged in the bone marrow canal 29, wherein the fixation plate 1 can be easily removed from the bone 28 after healing of the fracture by the curved shape of the shaft 8, since after loosening the Frxierungsmittel 13 and the anchoring screws 23, 24, the fixation plate 1 raised in a simple manner and the shaft 8 can be unscrewed without major injury to the surrounding bone wall 30 of the bone marrow canal 29

FIG. 7 shows in a purely schematic representation a possible angular distribution of the orientation of the fretting means 13 in the bone 28. For example, the orientation of the fretting means 13 in the bone 28 can be chosen such that at least along a sectional plane a corresponding fretting means 13 is provided in FIG Bone 28 is anchored

Although the present invention has been described in detail with reference to the accompanying drawings with respect to an exemplary embodiment, it is obvious to the person skilled in the art that the invention is not limited to this exemplary embodiment, but rather modifications or changes, for example with regard to omission of individual features or different combinations of the features presented are possible without departing from the scope of the appended claims. The present invention includes, in particular, all possible combinations of all featured individual features

Claims

A bone fixation plate having a plate-like head portion (2) for engaging a broken bone portion having a plurality of apertures (11, 12) for receiving fixation means (13) and an intramedullary shaft portion (8) for placement in the bone, wherein the shaft portion and head portion communicate with each other are connected, characterized in that the shank region (8) at least at its end facing away from the head region (4) has a curved along the longitudinal axis portion.

2. Fixation plate according to claim 1, characterized in that the shank region (8) is curved along the entire longitudinal extent.

3. Fixation plate according to one of the preceding claims, characterized in that the curvature is equal or different with respect to the radius of curvature along the entire curvature section.

4. Fixation plate according to one of the preceding claims, characterized in that one or more curvature sections are arranged with the same or different radii of curvature and / or section lengths.

5. Fixation plate according to one of the preceding claims, characterized in that the shaft region is curved at its, the head region remote from the underside (9). 6. Fixation plate according to one of the preceding claims, characterized in that the shaft region is curved at its, the head region facing upper side (10).

7. Fixation plate according to one of the preceding claims, characterized in that the curvature at the bottom and top of the shaft portion with respect to the radius of curvature and / or length and / or number of the curvature sections is the same or different. 8 fixing plate according to one of the preceding claims, characterized in that the curvature on the top portion facing the head portion (10) of the shaft portion concave and on the side facing away from the head portion underside (9) of the shaft portion is convexly formed

9 fixing plate according to one of the preceding claims, characterized in that the shank region (8) is formed by a rod with a square, rectangular, round, oval or polygonal cross-section 10 fixing plate according to one of the preceding claims, characterized in that the shank region (8) 11 fixing plate according to one of the preceding claims, characterized in that in the shank region (8) means (21, 22) are provided for receiving fastening means by a rod with a constant cross-section over its longitudinal extension or cross-section tapering to its free end

12 fixing plate according to one of the preceding claims, characterized in that the plate-like head portion (2) defines a plate plane (7) along which the head portion (2) extends in its largest dimension, and the shaft portion (8) in the connection area (3) 13 fixing plate according to one of the preceding claims, characterized in that the head region (2) has an extension (5) which extends in the direction of the shank region (8) to the head region has a Krummungsabschnitt whose tangent with the plate plane an acute angle (α) protruding beyond the connecting region (3) from the head region (2) and shaft region (8) and serving to rest against the bone. 14 Fixation plate according to one of the preceding claims, characterized in that

Positioning and connecting means (27, 41, 42) for a Zielgerat (15) are arranged

15. Operation set of a fixing plate (1) according to one of the preceding claims and a target device (15) for the positionally accurate arrangement of fixing means.