DEVICE FOR THE TREATMENT OF A FRACTURE

Description

[0001] The invention relates to a device for treating a fracture, in particular a fracture of the proximal femur such as a femoral neck fracture, comprising a plate for attachment to a femur, one or more intraosseous screws with which the plate can be fixed to a femoral shaft through intraosseous screw openings, a coupling device arranged proximal to the at least one intraosseous screw, in particular a bone screw, with which the plate can be connected to a femoral head through the femoral shaft and a femoral neck via a coupling device opening, wherein the coupling device is connected to the plate with some play, so that the coupling device is movable in the lateral direction relative to the plate. Such a device is known, for example, from US 2005 / 055024 A1.

[0002] Devices of the type mentioned above are known from the prior art for treating a femoral neck fracture. These devices consist of connecting a bone plate to the femoral shaft using intraosseous screws, and then connecting the femoral head to the plate via a coupling device, which is typically a bone screw. A movable connection between the coupling device and the plate is advantageous for promoting the healing process. It has been shown that small movements and compression at a contact surface between the fractured bone fragments, usually at a contact surface in the femoral neck region, are beneficial for promoting healing, although excessive sliding of the bone fragments must be avoided.

[0003] However, the devices known from the prior art, which in particular have so-called barrel and / or telescopic screws and are known, for example, from document WO 2007 / 109302 A2, have proven to be unwieldy.

[0004] This is where the invention comes in. The object of the invention is to provide a device of the type mentioned above, which is on the one hand easy to handle and on the other hand particularly advantageous for a healing process.

[0005] This problem is solved according to the invention by a device of the type mentioned at the outset, in which an adjustment device connected to the plate and which can be positioned at different positions relative to the plate is provided, with which the play can be adjusted.

[0006] Due to the inventive design of the device, the use of telescopic screws or the like is no longer necessary. Instead, it was recognized within the scope of the invention that a robust construction and, at the same time, simple adjustability of the play can be achieved in a straightforward manner by means of a suitable adjustment device. The adjustment device can, in principle, be designed in a variety of ways to influence the magnitude of the play within which the coupling device is movable relative to the plate.

[0007] It is advantageous if the adjustment device is essentially rigidly connected to the plate in both lateral and medial directions. This can be achieved, for example, by an adjustment device formed by an adjusting screw that can be screwed into the plate and by means of which the movement of the coupling device relative to the plate can be adjusted. The play of the coupling device relative to the plate can then be adjusted by the screw-in depth of the adjusting screw.

[0008] It is particularly preferred that the coupling device has a first stop surface which interacts with a corresponding surface on the adjustment device and / or the plate, such that the first stop surface limits the movement of the coupling device relative to the plate in the medial direction. The coupling device can thus be moved relative to the plate in the medial direction until the plate abuts the first stop surface, so that the first stop surface defines a medial end position of the coupling device relative to the plate.

[0009] This first stop surface can be designed in any way that, from a predefined position of the coupling device in the medial direction, rests against the adjustment device and / or the plate, thus preventing further movement in the medial direction. The stop surface can therefore be oriented either perpendicular to a longitudinal axis of the coupling device, along which this coupling device is movable relative to the plate, or at an angle to the longitudinal axis to achieve particularly low surface pressure.

[0010] For example, the coupling device may be designed with a lateral collar which, in conjunction with the plate, forms a stop up to which the coupling device can be inserted medially into the plate. The coupling device can then simply be used as a tension screw that pulls the femoral head towards the plate. The coupling device may then have, for example, a collar or shoulder at one lateral end that is larger than the coupling device opening, so that the coupling device can only be inserted medially into the plate up to the collar.

[0011] It is advantageous if the coupling device has a second stop surface which rests against the adjustment device in a lateral end position of the coupling device. This allows the play to be easily adjusted by changing the position of the adjustment device relative to the plate, especially since this also changes the distance between the stops.

[0012] The second stop surface can be formed by a single surface which, in the lateral end position, establishes contact between the coupling device and the adjustment device. However, it is also possible for the second stop surface to be formed by several surfaces acting in parallel, thus limiting movement particularly effectively. It has been shown that when using only a single second stop surface, especially one that rests against a medial thread end of the adjustment device, there is a risk that the adjustment device will slide along the coupling device or screw itself onto the second stop surface of the coupling device via the thread, resulting in movement being less restricted than intended. In particular, it is possible for the second stop surface to be formed by two or three parallel stops.Contact surfaces are formed, for example, by a primary, a secondary, and a tertiary second stop. The primary second stop can, for example, be located at a lateral end of the adjustment device, the secondary second stop at the center of the adjustment device, and the tertiary second stop at a medial end of the adjustment device.

[0013] It is advantageous if the second stop surface is at least partially formed by a lateral second stop surface which, in the lateral end position, bears at least partially against a shoulder or collar of the adjusting device, in particular against an adjusting screw collar, in a region of a lateral end of the adjusting device. The collar, preferably designed as an adjusting screw collar, can be arranged at a lateral end of the adjusting screw and have a larger diameter than the rest of the adjusting device, so that the coupling device bears against the adjusting device at a lateral end position. In this case, the second stop surface on the coupling device can be arranged on an end-side, lateral circumferential recess to achieve a corresponding positive fit with the collar on the adjusting device.

[0014] Preferably, the second stop surface is formed at least partially by a medial second stop surface on the coupling device, which, in the lateral end position, rests at least partially against a thread of the adjusting device. In particular, a medial end of the thread on the adjusting device can thus serve as a stop for a corresponding surface of the coupling device in order to limit the movement of the coupling device in the lateral direction.

[0015] It has proven effective to connect the adjustment device to the plate via a thread, incorporating a thread-locking element, particularly a plastic component, which increases friction in the thread to prevent the adjustment device from loosening. This effectively prevents the adjustment device from unintentionally detaching from the plate.

[0016] To easily avoid errors during installation of the device due to over-tightening, it is preferably provided that the adjustment device can only be screwed into the plate up to a predefined position, whereby this is implemented constructively in particular with a wrench, preferably an Allen wrench, which from a predefined position of the adjustment device no longer makes contact with a corresponding counterpart, in particular an Allen key, in the adjustment device.

[0017] It is advantageous if the coupling device is movable between a medial and a lateral end position between stops, whereby the medial end position is defined by a first stop surface on the coupling device in conjunction with the adjustment device, and the lateral end position by a second stop surface in conjunction with the adjustment device. The adjustment device thus defines the stops, which easily limit the movement of the coupling device. This allows both the position of the end positions and any play to be easily adjusted.

[0018] It has proven advantageous for the first and second stop surfaces to be arranged at an angle to each other, particularly at different angles to an adjustment direction along which the adjustment device is movable relative to the plate, especially at an angle to each other of 10 to 160 degrees, preferably 60 to 120 degrees, so that a movement of the adjustment device along the adjustment direction has varying effects on the lateral and medial end positions. Thus, a change in the position of the adjustment device can not only alter the position of the stops, but also the play, i.e., the mobility of the coupling device between the stops.In particular, if a stop surface is approximately parallel to the adjustment direction, a position of the adjustment device along the adjustment direction does not change the stop or the corresponding end position formed by the corresponding stop surface.

[0019] If, for example, the medial end position is defined by a first stop surface in conjunction with the adjustment device, which first stop surface is approximately parallel to the adjustment direction, a change in the position of the adjustment device along the adjustment direction does not change the medial end position.

[0020] It is advantageous if the second stop surface is approximately perpendicular to the adjustment direction and the first stop surface is approximately parallel to the adjustment direction, wherein, in particular, the adjustment direction is oriented at an angle of 0.5 degrees to 15 degrees, preferably 0.8 degrees to 2 degrees, to a longitudinal axis of the coupling device. Thus, a movement of the adjustment device along the adjustment direction causes a displacement of the second stop, but not of the first stop, so that any play can be easily adjusted.

[0021] It is particularly preferred that the adjustment device is designed as an adjusting screw and the coupling device as a bone screw, wherein a longitudinal axis of the adjusting screw is aligned at an angle of 0.5 degrees to 15 degrees, particularly 0.8 degrees to 2 degrees, to a longitudinal axis of the bone screw. Through the interaction of these two screws, play can thus be adjusted in a particularly simple manner. At the same time, a robust and easy-to-handle design is achieved. Typically, the adjusting screw and the bone screw are arranged adjacent to each other and preferably protrude through a common opening in the plate. This allows for the simple and space-saving implementation of stop surfaces between the adjusting screw and the bone screw, which limit play of the bone screw relative to the plate.

[0022] It has proven advantageous for the adjustment device to be designed as an adjusting screw, which is mounted in a thread in the plate and can be variably positioned by means of the thread. The thread is preferably self-locking. The adjustment device can thus only be moved laterally or medially by rotation, but not by pressure in either direction. This allows for particularly precise adjustment of the play.

[0023] Preferably, the adjustment device can be positioned variably along an adjustment direction, in particular along a threaded axis, relative to the plate.

[0024] It is particularly advantageous if the adjustment direction is aligned at an angle of 0.5 to 10 degrees, and especially 0.8 to 2 degrees, to a longitudinal axis of the coupling device, with the adjustment direction and a longitudinal axis of the coupling device preferably lying in the same plane. This allows for particularly precise adjustment of the play. A first stop surface can then be easily achieved in the design, in particular, against which the coupling device rests in a medial end position on the adjustment device. This stop surface is aligned at a corresponding angle to a longitudinal axis of the coupling device, and the coupling device rests against the adjustment device at this point, resulting in particularly low surface pressure due to the small angle. This provides exceptionally high stability.

[0025] Preferably, the coupling device has a shoulder which adjoins, in particular, a chamfered area, the shoulder forming a second stop surface which, in a lateral end position of the coupling device, rests against the adjusting device, particularly at its end face. Thus, the clearance across the two stop surfaces is clearly defined.

[0026] It is particularly advantageous if the two stop surfaces are arranged at different angles to the adjustment direction of the adjusting screw, along which direction the adjusting screw can be moved relative to the plate. This means that moving the adjusting screw along the adjustment direction has different effects on the medial and lateral end positions of the coupling device, allowing the play to be adjusted easily.

[0027] The adjustment device is preferably designed as an adjusting screw and therefore typically has an approximately cylindrical surface. With a corresponding chamfered surface on the coupling element, this results in line contact between the adjustment device and the coupling element in the area of ​​the chamfered surface, which can serve as the first stop surface. This stop surface is oriented obliquely, i.e., not perpendicular, to the direction of movement of the coupling element along its longitudinal axis. This results in good force transmission at the first stop surface. If the second stop surface is located on a shoulder or...At a transition from the chamfered area to an adjoining, for example, cylindrical area, the second stop surface can be oriented approximately perpendicular to the longitudinal axis of the coupling device. This means that movement of the adjusting device along the adjustment direction has varying effects on the medial end position, which is typically caused by the first stop surface in conjunction with the adjusting device, and the lateral end position, which is typically caused by the second stop surface in conjunction with the adjusting device. Therefore, the play can be easily changed by altering the position of the adjusting device along the adjustment direction, even though both stop surfaces interact with the adjusting device.

[0028] The cylindrical area of ​​the coupling device usually connects medially to the conical area, so that a shoulder is formed between the conical area and the cylindrical area, which can be used as a second stop surface to limit movement of the coupling device in the lateral direction relative to the plate.

[0029] It is advantageous if the coupling device has a chamfered section and the adjusting device has an approximately cylindrical outer contour, at least in part. The chamfered section of the coupling device forms a first stop surface, which, in conjunction with the approximately cylindrical outer contour of the adjusting device, limits the movement of the coupling device relative to the plate in the medial direction. A cylindrical outer contour of the adjusting device results, for example, when the adjusting device is formed by an adjusting screw. This ensures particularly good force transmission between the coupling device and the adjusting device and allows for a simple and robustly adjustable stop to define a clearance.

[0030] It is particularly preferred that the chamfered area is aligned at a chamfer angle to a longitudinal axis of the coupling device, which corresponds to an angle at which the adjustment device is aligned to the longitudinal axis of the coupling device, and that the adjustment device is arranged such that it contacts the chamfered area. The adjustment device can then be screwed into the plate along the adjustment direction without colliding with the coupling device, so that the position of a lateral end position can be easily changed. A medial end position is then generally determined by the dimensions of the adjustment device and the coupling device and can be independent of the position of the adjustment device along the adjustment direction.

[0031] It is advantageous if a tension screw is provided which is arranged approximately parallel to a longitudinal axis of the coupling device, in particular proximal to the coupling device, with which tension screw the plate can be connected to the femoral head at a tension screw opening through the femoral shaft and a femoral neck in order to prevent rotation of the femoral head relative to the coupling device.

[0032] Typically, the longitudinal axis of the coupling device is aligned with the longitudinal axis of the first screw at a femoral neck angle of 10 to 60 degrees, particularly 35 to 45 degrees. These angles result from the arrangement and orientation of the coupling device opening and the first openings in the plate and are advantageous for treating femoral neck fractures, especially since the angle between the femoral neck and shaft is usually around 130 degrees.

[0033] Preferably, the coupling device is designed to be hollow, so that bone cement can be introduced through the coupling device in the area of ​​the femoral head when the device is arranged on a femur.

[0034] Preferably, the lag screw is also hollow, in order to allow bone cement to be introduced into the area of ​​the femoral head through it if necessary.

[0035] Further features, advantages, and effects of the invention will become apparent from the exemplary embodiment described below. The drawings referenced therein show: Fig. 1 and 2 a device according to the invention in different views; Fig. 2a a detail of the Fig. 1 ; Fig. 3 and 4 a detail of the device in different operating states; Fig. 5 und 6 Illustrations that demonstrate the operating principle of the device; Fig. 7 and 8 Details of another device according to the invention.

[0036] Fig. 1 Figure 1 shows a device 1 according to the invention in a sectional view of a femur with a femoral shaft 4, a femoral neck 2 and a femoral head 7. Fig. 2 This device 1 is shown without the femur in a 3D view.

[0037] It is evident in each case that a plate 3 is provided which can be attached to the outside of a femur, opposite a femoral neck 2, and can be connected in a lower area to the femoral shaft 4 by means of intraosseous screws 10 which protrude through intraosseous screw openings 14 in the plate 3.

[0038] Above the intraosseous screws 10, or proximal to them, a coupling device, formed here by a bone screw 5, and a lag screw 19 are provided. These are designed as shaft screws and have a thread 15 only in one end region. This makes it possible to pull the femoral head 7, into which these screws are screwed, against the femoral neck 2 or the femoral shaft 4, thus stabilizing the fracture. For this purpose, a coupling device opening 6, through which the bone screw 5 protrudes, and a lag screw opening 20, through which the lag screw 19 penetrates the plate 3, are provided in the plate 3. The bone screw has a collar 22 at one lateral end, which rests against the coupling device opening 6 and thus forms a stop up to which the bone screw can be inserted medially into the plate.

[0039] The bone screw 5 is connected to the plate 3 with a play 21 in the medial direction 11 and the lateral direction 8. This play 21 results from the movement of the coupling device relative to the plate 3 between a first stop and a second stop, each of which is located on an adjustment device formed here by an adjusting screw 9. The adjusting screw 9 has a thread 15 that corresponds to a thread 15 in the plate 3, so that the adjusting screw 9 can be screwed into the plate 3 along an adjustment direction 16, approximately in the medial direction 11, or unscrewed from the plate 3 in the opposite direction, approximately in the lateral direction 8, in order to influence the play 21 of the bone screw 5 relative to the plate 3, and thus the movement of the femoral head 7 relative to the femoral neck 2.

[0040] The first stop is formed by a first stop surface 12 on the bone screw 5 in a chamfered area 17. This first stop surface 12 rests circumferentially against the adjusting screw 9 in the medial end position of the bone screw 5. Thus, the adjustment direction 16 is not parallel to a longitudinal axis of the bone screw 5, but rather at an angle α of approximately 1.2 degrees to it. The chamfered area 17 on the bone screw 5 is approximately parallel to the adjustment direction 16. A normal to the chamfered area 17 is therefore approximately perpendicular to the adjustment direction 16, so that the medial end position is independent of the insertion depth of the adjusting screw 9. Furthermore, in the medial end position, the bone screw 5 rests against the plate 3 via the collar 22 provided at its lateral end, so that this collar 22 also forms a stop and defines the medial end position.

[0041] The second stop is formed by a second stop surface 13 in a region of a shoulder of the bone screw 5, which is located in an area between the chamfered region 17 and a cylindrical region 18 of the bone screw 5. This shoulder rests against the end face of the adjusting screw 9 in a lateral end position of the bone screw 5. The lateral end position thus changes with the screw-in depth of the adjusting screw 9 along the adjustment direction 16. A change in the position of the adjusting screw 9 relative to the plate 3 therefore results in a change in the lateral end position of the bone screw 5 and thus a change in the play 21.

[0042] Proximal to the bone screw 5, another lag screw 19 is provided, which is also screwed from the plate 3 into the femoral head. This additional lag screw 19 stabilizes the femoral head 7 on the femoral neck 2 and prevents rotation of the femoral head 7 around the bone screw 5 or the coupling device.

[0043] As can be seen, the bone screw 5 and the lag screw 19 are aligned approximately parallel and at a femoral neck angle γ of approximately 20 degrees to 40 degrees to the intraosseous screws 10.

[0044] Fig. 2a shows an enlarged detail of the Fig. 1 The circumferential collar 22 is particularly visible here. In the medial end position of the bone screw 5, it rests against the plate 3, thus forming a stop up to which the bone screw 5 can be inserted into the plate 3. As can be seen, the coupling device opening 6 is smaller than the collar 22, but large enough to allow the bone screw 5 to be inserted through the coupling device opening 6 into the plate 3 up to the collar 22.

[0045] Fig. 3 and 4 The bone screw 5 and the adjusting screw 9 of the in Fig. 1 and 2 The device shown in 1 is described in detail. Fig. 3 The bone screw 5 and the adjusting screw 9 are shown in a medial end position of the bone screw 5, i.e., when the femoral head 7 is maximally spaced from the femoral neck 2. As can be seen, no further movement of the bone screw 5 in the medial direction is possible, since the bone screw 5 rests against a circumferential area of ​​the adjusting screw 9 at the beveled area 17, which forms the first stop surface 12. However, movement of the bone screw 5 and the femoral head 7, into which the bone screw 5 is usually screwed at its end, in the opposite direction, i.e., in the lateral direction 8, would be possible from this position.

[0046] As can be clearly seen here, the first stop surface 12 and the second stop surface 13 are arranged relative to each other at a stop surface angle δ of approximately 110 degrees. The first stop surface 12 is oriented approximately parallel to the adjustment direction 16, so that the second stop surface 13 is oriented at an angle α of approximately 110 degrees to the adjustment direction 16. Therefore, a change in the position of the adjusting screw 9 along the adjustment direction 16 only changes the lateral end position, but not the medial end position, which is also determined by the collar 22.

[0047] Fig. 4 Figure 5 shows the bone screw 5 and the adjusting screw 9 in a lateral end position of the bone screw 5, i.e., when the femoral head 7 cannot be moved any closer to the femoral neck 2, and thus no further lateral movement of the bone screw 5 is possible. As can be seen, in this lateral end position, the bone screw 5 rests against a second stop surface 13 formed by a shoulder on the bone screw 5, approximately at its end face, against the adjusting screw 9.

[0048] A bevel angle β, at which the beveled section 17 is aligned with a longitudinal axis of the bone screw 5, corresponds approximately to an angle α, at which the adjustment direction 16 is aligned with the longitudinal axis of the bone screw, such that the beveled section 17 is approximately parallel to the adjustment direction 16. Therefore, a change in the insertion depth of the adjusting screw 9 has no effect on the position of the medial end position. This is determined solely by the dimensions of the bone screw 5 and the adjusting screw 9 and the angle α. However, the position of the lateral end position does change with the insertion depth of the adjusting screw 9, as this depends on the position of an end face of the adjusting screw 9. By changing the insertion depth of the adjusting screw 9, a play 21 can therefore be easily set via the lateral end position, by which the bone screw 5 can be moved relative to the plate 3.This adjustability is particularly important for the rapid healing of a corresponding fracture.

[0049] As in Fig. 1 , 3 and 4 The bone screw 5 is evidently hollow, so that bone cement can be introduced through it into an area of ​​a femoral head 7, for example to fix the bone screw 5 there.

[0050] Fig. 5 und 6 In this context, the figures show the influence of the screw-in depth of the adjusting screw 9 on the clearance 21, whereby dimensions and angle α are not shown to scale for better illustration. As can be seen, due to the chamfered area 17 of the bone screw 5 being approximately parallel to the adjustment direction 16, the first stop surface 12, or a medial end position, does not change with a screw-in depth of the adjusting screw 9 along the adjustment direction 16. However, the screw-in depth has a direct effect on the second stop surface 13, which defines the lateral end position. Thus, the figures show Fig. 5 a situation in which the adjusting screw 9 is screwed far into the plate 3 (not shown) so that no play 21 remains. In this situation, the bone screw 5 rests against both the first stop surface 12 and the second stop surface 13. In the Fig. 6 In the situation shown, the adjusting screw 9 is positioned further out laterally, or not as far as in Fig. 5 shown screwed into plate 3.

[0051] The adjusting device, designed as an adjusting screw 9, is aligned at an angle α of approximately 1.2 degrees to the longitudinal axis of the bone screw 5. The conical section of the screw is also formed with a corresponding conical angle, resulting in line contact between the adjusting screw 9 and the conical section of the bone screw 5, thus ensuring particularly good stabilization and force transmission. It is also evident that the first stop surface 12 is aligned at a stop surface angle δ to the second stop surface 13, which is approximately 90 degrees in this case, so that a change in the position of the adjusting screw 9 has different effects on the medial and lateral end positions.

[0052] Although the exemplary embodiments show a corner or edge at the connection between the first stop surface 12 and the second stop surface 13, it is understood that the first stop surface 12 and the second stop surface 13 could also be connected, for example, by a rounded edge and still have a corresponding stop surface angle δ relative to each other. The bone screw 5 can therefore be easily manufactured, for example, using a ball end mill, a shank end mill, or the like.

[0053] Fig. 7 and 8Figure 1 shows details of a further embodiment of a device 1 according to the invention. This device 1 has a second stop surface 13 formed by two parallel contact surfaces, namely a primary second stop surface 13 on the coupling device, which in the lateral end position rests against a medial threaded end of the adjusting device, and a secondary second stop surface 13a at a lateral end of the adjusting device, which forms the secondary second stop surface 13a as shown in Figure 1. Fig. 8This is evident in detail from an adjusting screw collar 23, i.e., a section of the adjusting screw 9 with a larger diameter than the rest of the adjusting screw 9, in conjunction with an end taper or circumferential recess on the coupling device, i.e., here the bone screw 5. The two second stop surfaces 13, 13a, which act in parallel, effectively prevent unintentional sliding of the adjusting screw 9 along the coupling device and thus reliably limit its movement.

[0054] A device 1 according to the invention enables the treatment of a fracture of a femur in a particularly simple way and ensures particularly good healing due to the easily adjustable play 21.

Claims

1. A device (1) for treating a fracture, in particular a fracture of a proximal femur such as, for example, a femoral neck fracture, having a plate (3) for attaching to a thigh bone, one or more intraosseous screws (10) by means of which the plate (3), through intraosseous screw openings (14), can be fixed to a thigh shaft (4), a coupling device, in particular a bone screw (5), which is arranged proximally to the at least one intraosseous screw (10), by means of which the plate (3) can be connected at a coupling device opening (6) through the thigh shaft (4) and a thigh neck (2) to a thigh head (7), wherein the coupling device is connected to the plate (3) with play (21) such that the coupling device can be moved in the lateral direction (8) relative to the plate (3), wherein an adjusting device is provided which is connected to the plate (3) and can be positioned at different positions relative to the plate (3), by means of which the play (21) can be adjusted, characterized in that the coupling device is movable between stops between a medial end position and a lateral end position, wherein the medial end position is defined by a first stop surface (12) on the coupling device in cooperation with the adjusting device, and the lateral end position is defined by a second stop surface (13) in cooperation with the adjusting device.

2. The device (1) according to Claim 1, characterized in that the adjusting device is connected to the plate (3) substantially rigidly in the lateral direction (8) and the medial direction (11).

3. The device (1) according to Claim 1 or 2, characterized in that the coupling device has a first stop surface (12), which cooperates with a corresponding surface on the adjusting device and / or the plate (3), so that a mobility of the coupling device relative to the plate (3) in medial direction (11) is limited by the first stop surface (12).

4. The device (1) according to one of Claims 1 to 3, characterized in that the coupling device has a collar (22) laterally which in cooperation with the plate (3) forms a stop, up to which the coupling device can be introduced medially into the plate (3).

5. The device (1) according to one of Claims 1 to 4, characterized in that the coupling device has a second stop surface (13), which lies against the adjusting device when the coupling device is in a lateral end position.

6. The device (1) according to Claim 5, characterized in that the second stop surface (13) is formed at least partly by a lateral second stop surface (13a) which in the lateral end position at least partly lies against a shoulder or flange of the adjusting device, in particular against an adjusting screw flange (23), in a region of a lateral end of the adjusting device.

7. The device (1) according to Claim 5 or 6, characterized in that the second stop surface (13) is formed at least partly by a medial second stop surface on the coupling device, which at least partly lies against a thread of the adjusting device in the lateral end position.

8. The device (1) according to one of Claims 1 to 7, characterized in that the adjusting device is connected to the plate (3) by a thread, wherein a screw lock, in particular a plastic part is provided, which increases a friction in the thread in order to prevent the adjusting device from becoming detached.

9. The device (1) according to one of Claims 1 to 8, characterized in that the adjusting device can only be screwed into the plate (3) as far as a predefined position, wherein this is implemented structurally in particular with a wrench, preferably an Allen wrench, which no longer produces a contact with a corresponding counterpart, in particular an internal hexagon in the adjusting device, beyond a predefined position of the adjusting device.

10. The device (1) according to one of Claims 1 to 9, characterized in that the first stop surface (12) and the second stop surface (13) are arranged at a stop surface angle (δ) relative to one another, in particular at different angles to an adjustment direction (16), along which the adjusting device is movable relative to the plate (3), in particular at a stop surface angle (δ) relative to one another from 10 degrees to 160 degrees, preferably 60 degrees to 120 degrees, so that a movement of the adjusting device along the adjustment direction (16) has effects of different extent on the lateral end position and the medial end position.

11. The device (1) according to Claim 10, characterized in that the second stop surface (13) is approximately normal to the adjustment direction (16), and the first stop surface (12) is approximately parallel to the adjustment direction (16), wherein in particular the adjustment direction (16) is aligned at an angle (α) to a longitudinal axis of the coupling device from 0.5 degrees to 15 degrees, preferably 0.8 degrees to 2 degrees.

12. The device (1) according to one of Claims 1 to 11, characterized in that the adjusting device is embodied as adjusting screw (9) and the coupling device is embodied as bone screw (5), wherein a longitudinal axis of the adjusting screw (9) is aligned at an angle (α) from 0.5 degrees to 15 degrees, in particular 0.8 degrees to 2 degrees, to a longitudinal axis of the bone screw (5).

13. The device (1) according to one of Claims 1 to 12, characterized in that the adjusting device is embodied as adjusting screw (9), which is arranged in a thread (15) in the plate (3) and is able to be positioned variably by means of the thread (15).

14. The device (1) according to one of Claims 1 to 13, characterized in that the adjusting device is able to be positioned in a changeable manner along an adjustment direction (16), in particular along a thread axis, relative to the plate (3).

15. The device (1) according to Claim 14, characterized in that the adjustment direction (16) is aligned at an angle (α) from 0.5 degrees to 10 degrees, in particular 0.8 degrees to 2 degrees relative to a longitudinal axis of the coupling device, wherein preferably the adjustment direction (16) and a longitudinal axis of the coupling device lie in one plane.