Kit for treating bone fractures

Abstract

The invention relates to a kit (1) for treating a bone fracture, in particular for treating a femoral neck fracture, comprising an intramedullary nail (2) having an opening (6) with a first opening region (61) for receiving a bone screw (3) and a second opening region (62) for receiving an adjustment and / or fixation screw (4) for the bone screw (3), wherein the first opening region (61) is connected to the second opening region (62) in a transition region (63), and optionally a multi-part sleeve (5) and a plurality of drill wires (7). In order to be able to correct if a drill wire (7) for a bone screw (3) is positioned too high or too low, the invention provides that the opening (6) of the intramedullary nail (2) has a size at the transition region (63) which is greater than the outer diameter of a drill wire (7).

Description

Technical Field

[0001] The present invention relates to a kit for treating fractures, particularly for treating femoral neck fractures, comprising an intramedullary nail having an opening having a first opening region for receiving a bone screw and a second opening region for receiving an adjusting and / or fixing screw for the bone screw, wherein the first opening region is connected to the second opening region in a transition region, and optionally a multi-part sleeve and a plurality of drill wires. Background Technology

[0002] Femoral neck fractures are relatively common, particularly affecting elderly patients. Treatment of femoral neck fractures in the elderly is challenging for several reasons: First, the fractured femoral head fragments must be correctly positioned relative to their separated parts of the femur for proper healing. Healing takes several weeks, during which the forces acting on the fractured bone fragments (e.g., through surrounding muscles) can change significantly. Therefore, proper alignment of the separated bone fragments during surgery is crucial and complex due to the presence of multiple variables. Second, the bone structure of the elderly is often significantly inferior to that of younger people, which can make anchoring bone screws in the femoral head more difficult.

[0003] Numerous different devices for treating femoral neck fractures are known in the prior art. For example, plate-based solutions are known, in which the plate is fixed to the femur by screws, and the femoral head is anchored by additional screws extending through the plate. Devices using intramedullary nails are also frequently employed today. The intramedullary nail is driven into the medullary canal of the femur and includes at least one proximal opening through which the bone screw can be guided. The bone screw, guided through the proximal opening, is screwed into the femoral head. Where appropriate, the desired compression can be achieved to move the femoral head fracture fragment or the femoral neck fracture fragment toward the base of the femoral neck via the bone screw, thereby bringing the two fractured bone parts into contact with each other, and where appropriate, applying a defined compressive force. Devices capable of achieving this with relatively fine adjustment have been developed for this purpose. These devices typically employ two screws: a bone screw anchored in the femoral head and an adjustment and / or fixation screw for the bone screw; additionally, one or more distal screws are provided for distal locking. The function of the adjustment and / or fixation screw can vary depending on the device. In most cases, adjusting and / or fixing screws are configured to interact with bone screws such that the paired arrangement of the two screws initially prevents rotation of the femoral head. Advanced devices are also known that are capable of controlling the force to be applied in the lateral direction and / or, where appropriate, also allow for limited lateral movement of the bone screws during the healing process. For example, US 7,527,627 B2 describes a system by which compression can be achieved using a paired arrangement comprising bone screws and adjusting and / or fixing screws. For example, DE 20 2022 002 403 U discloses a device for treating femoral neck fractures in which the paired arrangement of bone screws and adjusting and / or fixing screws provides a configuration in which the lateral clearance of the bone screws is adjustable during the healing process while providing rotational locking.

[0004] Therefore, devices according to the prior art, comprising an intramedullary nail and bone screws (“tension screws”) and adjusting and / or fixing screws (“fixing screws”), offer the possibility of effective load-bearing and accommodating relative movement. When using such devices, the process typically proceeds as follows: First, the intramedullary nail is inserted into the medullary canal of the femur. A suitable aiming module is used for this purpose, through which the intramedullary nail can be moved within the bone. Subsequently, a sleeve is attached to the aiming module. The sleeve typically extends obliquely relative to the inserted intramedullary nail, which in the inserted state extends approximately along the leg axis. The tissue is then cut through the sleeve via an incision. An additional sleeve component, namely a tissue-protecting sleeve, can then be inserted to obtain an unobstructed passage through the tissue to the bone. A drill wire is then inserted into the sleeve and the tissue-protecting sleeve. The drill wire serves as a guide for the drill bit. The drill bit can then be used to drill corresponding holes for receiving the bone screws and adjusting and / or fixing screws. Subsequently, a bone screw is first inserted and then rotated and locked using adjusting and / or fixing screws; prior to this, a compression step may optionally be performed by laterally moving the bone screw, and thus the femoral head; and optionally, the bone screw may be allowed to make a predetermined lateral movement during the healing process.

[0005] While existing devices with intramedullary nails, bone screws, and adjusting and / or fixing screws offer excellent adjustability for healing, a crucial aspect remains unresolved: the precise determination of bone screw placement. In principle, the bone screw's position is determined by a first drill wire, which then guides the drill bit, creating a hole in the femoral head that further defines the screw in the medial, caudal / cranial, and rotational directions. If the drill wire is mispositioned in the caudal / cranial direction, this error is propagated to the bone screw's placement. Although mispositioning of the drill wire can be detected during surgery using imaging methods, there are no corrective mechanisms, or the corrective mechanisms are insufficient. Typically, according to existing techniques, to correct this, the drill wire is frequently removed again, the implant is manually repositioned using an aiming module, and a new hole is drilled, where the drill wire may, in most cases, deviate into the existing drilled channel, resulting in inaccurate placement for subsequent surgical steps. If the drill wire remains in the wrong position, optimal conditions for subsequent healing cannot be provided because the weight-bearing bone screw connected to the femoral head is not optimally positioned. Summary of the Invention

[0006] This is precisely where the present invention comes in. The object of the present invention is to further develop a kit of the type described at the beginning, such that if the first drill wire actually intended for the bone screw is mispositioned, the drill wire for the bone screw can still be correctly positioned during surgery with a small amount of manipulation.

[0007] This objective is achieved by having the opening of the intramedullary nail in the transition region of the kit described at the beginning be larger than the outer diameter of the drill wire.

[0008] A particular advantage of this invention is that the drill wire used to guide the drill bit in forming the bone screw hole can still be correctly inserted, even if the first drill wire, which was actually intended for the bone screw but was positioned too distally or too proximally, has been positioned. Because the opening in the intramedullary nail for receiving both the bone screw and the adjusting and / or fixing screw is configured to provide a continuous opening with a first opening region and a second opening region, wherein the size of the opening at the transition region is larger than the outer diameter of the drill wire, the intramedullary nail, along with the aiming module connected thereto, can be displaced according to the required correction, so that the next drill wire to be inserted can be inserted into the correct position suitable for the bone screw. In this way, both cranial and caudal corrections are easily achieved. For example, if the first drill wire, which was actually intended for the bone screw, was positioned too distally, the intramedullary nail can be raised so that the inserted first drill wire is no longer above but below, thus becoming the drill wire for determining the hole for adjusting and / or fixing the screw. The second drill wire for determining the hole for the bone screw can then be positioned above this drill wire. If the first drill wire was positioned too proximally, correction can be performed in a similar manner. In this configuration, the second drill wire is first inserted below, i.e., on the underside. This second drill wire is no longer used to define the hole for adjusting and / or fixing the screw, but is now used for the bone screw. After removing the drill wire located above, the intramedullary nail can then be repositioned again, this time distally. As a result, the positioned and previously below second drill wire is now above, thus defining the location for the hole for the bone screw. The lower drill wire used to define the hole for adjusting and / or fixing the screw can then be inserted below.

[0009] During the procedure, the position of the drill wire and other components of the kit used to treat the fracture is monitored using imaging methods, enabling the detection and correction of suboptimal drill wire placement. Cranial and caudal correction possibilities are achieved through a specific construction of the transition region of the opening relative to the outer diameter of the corresponding drill wire.

[0010] The first opening region is typically configured to have a larger free internal diameter than the second opening region. This is because bone screws are usually configured to be significantly thicker than non-load-bearing adjusting and / or fixing screws. The first opening region may be located above the second opening region in a proximal-to-distal direction, anterior to the leg axis, or along the leg axis, although reverse configuration is also possible. Bone screws and adjusting and / or fixing screws may also be positioned in a plane perpendicular to or intersecting the vertical leg axis at a defined angle. In this case, correction is not performed upward or downward, but to the left or right, or a combination of both. Typically, correction can be performed in the plane where the intramedullary nail is movable, and therefore also in a plane extending relative to the leg axis or the femoral normal or oblique direction, when the drill wire has been fixed.

[0011] The sleeve is preferably configured for inserting a bone screw and adjusting and / or fixing the screw, wherein the region for the bone screw is adjacent to the region for adjusting and / or fixing the screw, and wherein the free diameter of the sleeve or a portion thereof in the boundary region between the bone screw and the adjusting and / or fixing screw is greater than the outer diameter of the drill wire. Therefore, the remainder of the sleeve can move smoothly as a whole around the fixed drill wire. The sleeve can be configured as a multi-part sleeve having an outer sleeve component and may include an inner tissue protective sleeve housed within the outer sleeve component. The inner tissue protective sleeve can be configured with slots facing each other. As a result, similar to the opening in an intramedullary nail, the sleeve can be displaced around a fixed first drill wire, such that the first drill wire can become a drill wire for adjusting and / or fixing the screw, and a second drill wire can then define the precise position for the bone screw.

[0012] The internal tissue protection sleeve can be constructed to be elongated and U-shaped in cross-section transverse to the longitudinal axis, with the open areas of the tissue protection sleeve facing each other. This easily ensures that the drill wire fixed in the femoral head can be displaced from an upper position to an lower position or vice versa by moving the rest of the sleeve relative to the fixed drill wire. The open U-shaped tissue protection sleeve readily allows this. Simultaneously, it provides the necessary tissue protection and unobstructed access for surgery.

[0013] Particularly preferred is that the sleeve or a portion thereof, particularly the tissue protection sleeve, is configured to have holes, wherein the holes are preferably arranged along a straight line between the inner and outer ends. These holes are arranged on the side of the tissue protection sleeve or a portion thereof (e.g., the inner tissue protection sleeve). By arranging them along a straight line, the position of the drill wire can be detected using imaging methods. By arranging them along a straight line, the rest of the kit can be aligned relative to the straight drill wire, such that the corresponding line containing the holes coincides with the drill wire. Then, a second inserted drill wire is automatically aligned parallel to the first inserted drill wire.

[0014] For operation of the kit, it is suitable that the kit includes an aiming module. On one hand, the intramedullary nail can be moved via the aiming module. The aiming module is configured to connect to the intramedullary nail at one end. At the opposite outer end, the aiming module is configured to receive a sleeve.

[0015] Intramedullary nails may include one or more additional openings distally for receiving screws that provide distal fixation to the bone nail.

[0016] Advantageously, the kit includes two drill wires of identical construction. Because the kit is designed so that the two drill wires can be interchanged in function with respect to their original purpose—the drill wire used to determine the hole for the bone screw becomes the drill wire used to determine the hole for adjusting and / or fixing the screw, and vice versa—the identical construction of the drill wires provides the necessary flexibility.

[0017] Particularly advantageously, the kit may also include a correction sleeve for multiple drill wires, wherein the correction sleeve includes multiple channels for receiving the drill wires, and wherein the distance between the channels is less than the distance between the center of the first opening region and the center of the second opening region. Using this correction sleeve (which is preferably also releasably fixed to the outside of the aiming module), minor corrections can be performed, for example, when the drill wire is positioned slightly too high. In this case, the correction sleeve can be fitted onto the positioned drill wire, then providing a base for inserting subsequent drill wires slightly downwards. For this purpose, the spacing between the channels of the correction sleeve is correspondingly small. For example, the spacing between the channels of the correction sleeve can be less than 5 mm, particularly less than 3 mm, for example less than 2.5 mm.

[0018] A method for correcting incorrect positioning of a first drill wire, particularly when the first drill wire is positioned too proximally or too distally, wherein an intramedullary nail is used in the method, wherein a bone screw is guided through the intramedullary nail and fixed in the femoral head, wherein adjusting and / or fixing screws are preferably provided for rotational locking and / or for determining the possibility or limitation of lateral movement of the bone screw, comprising the following steps:

[0019] - Determine the location of the drill wire, particularly the one inserted into the femoral head, for determining the holes for bone screws, especially during surgery using imaging methods;

[0020] - Optionally remove one of multiple (especially two) drill wires;

[0021] - Displace the intramedullary nail around the fixed drill wire used for the bone screw, so that the fixed drill wire defines the location of the drill hole used for the bone screw.

[0022] In particular, in these method steps, a kit according to the invention can be used, which is advantageously suited for performing this method.

[0023] This method offers the advantage that, when it is determined that the drill wire used to determine the location of the bone screw has been incorrectly inserted, its positioning can be corrected during surgery in both cranial and caudal directions. Minor corrections, which may be important in individual cases, can also be made when a correction sleeve is used. The method and its individual steps are explained in detail in the exemplary embodiments below. Attached Figure Description

[0024] Other features, advantages, and effects of the present invention can be derived from the exemplary embodiments presented below. Exemplary embodiments are shown as follows:

[0025] Figure 1a This is a side view of a kit used to treat bone structures;

[0026] Figure 1b yes Figure 1a Cross-section in the middle intramedullary nail region;

[0027] Figure 1c It is horizontal Figure 1a The cross-section of the tissue protection sleeve of the middle kit;

[0028] Figures 2 to 6 This diagram relates to the correction process for a drill wire that has been positioned too low.

[0029] Figures 7 to 13 It is the process of correcting a drill wire that has been positioned too high;

[0030] Figure 14 It is a calibration sleeve;

[0031] Figures 15 to 23 The drill wire is corrected using a lateral correction sleeve;

[0032] Figure 24 It is an intramedullary nail in the inserted state, which has bone screws and adjusting and / or fixing screws. Detailed Implementation

[0033] Figures 1a to 1c Side view ( Figure 1a ) and two cross sections ( Figure 1b and Figure 1c The following diagram illustrates kit 1 according to the invention. Kit 1 includes an intramedullary nail 2, which is used in... Figures 1a to 1c The intramedullary nail 2 is not yet fully visible and is located within the femur. The intramedullary nail 2 is connected to the aiming module 11. For this purpose, the aiming module 11 is configured such that it can be connected to the intramedullary nail 2 at its medial end 9, and vice versa. This connection is releasable. Through the aiming module 11, the intramedullary nail 2 can be moved and positioned within the femur.

[0034] Furthermore, kit 1 includes a sleeve 5. Sleeve 5 includes an outer sleeve component 51 and inner tissue protection sleeves 52 and 53. Sleeve 5 is inserted into a receiving portion for sleeve 5 at the outer end 10 of aiming module 11. Sleeve 5 is specifically provided because the two tissue protection sleeves 52 and 53 are positioned with slight convergence relative to each other—approximately 0.5° to 3°. In particular, when the two tissue protection sleeves 52 and 53 are guided parallel to each other, they can also be directly received by aiming module 11. In this case, sleeve component 51 can be omitted, and sleeve 5 is formed by the two tissue protection sleeves 52 and 53, or optionally by only one of the tissue protection sleeves 52 and 53.

[0035] like Figure 1aAs clearly visible, drill wire 7 is inserted into kit 1. A suitable, externally positioned guide sleeve 12 is inserted into the sleeve component 51 of sleeve 5 for inserting and guiding drill wire 7. Drill wire 7, and other drill wires 7 used when kit 1 is in use, generally have a constant outer diameter along the longitudinal extension direction of drill wire 7. The diameter variation occurs only at the first end of drill wire 7 driven into the femoral head due to the threads. Figure 1b As clearly visible in the cross-section, the intramedullary nail 2 includes an opening 6 having a first opening region 61 and a second opening region 62. A transition region 63 lies between the first opening region 61 and the second opening region 62. The first opening region 61 is generally configured to be smooth internally and receives the bone screw 3, which will be shown later. Thus, the bone screw 3 is generally repositionable within the intramedullary nail 2 because the first opening region 61 is configured without internal threads. The second opening region 62 is designed for adjusting and / or fixing the screw 4 and includes internal threads for receiving and fixing the adjusting and / or fixing screw 4, which is configured to have corresponding external threads. The adjusting and / or fixing screw 4 interacts with the bone screw 3 to limit the maximum lateral displacement of the bone screw 3 during the healing process. The typical range of movement of the bone screw 3 extends from 0 mm to 15 mm, particularly from 0 mm to 10 mm.

[0036] from Figure 1b It is evident that the transition region 63 between the first opening region 61 and the second opening region 62 is constructed to be sufficiently wide such that the drill wire 7 can enter the second opening region 62 from the first opening region 61 when the intramedullary nail 2 is displaced. In other words, the outer diameter of the drill wire 7 is smaller than the free diameter of the opening 6 in the transition region 63. Since the drill wire 7 is already fixed in the femoral head, it can only enter the second opening region 62 from the first opening region 61 by displacing the intramedullary nail 2. If the situation were reversed, i.e., the drill wire 7 were located in the second opening region 62, it would also be possible for the drill wire 7 to first be located in the second opening region 62 and then in the first opening region 61 after the intramedullary nail 2 has been displaced, through linear displacement of the intramedullary nail 2.

[0037] For a sleeve 5 that can be composed of multiple parts, the positional change of the drill wire 7 from the upper position to the lower position can also be achieved, and vice versa. For example... Figure 1c As is clearly visible in the exemplary embodiment, the sleeve 5, in addition to the outer sleeve component 51, also includes inner tissue protective sleeves 52 and 53, which are configured to be elongated and have longitudinal axes X and Y (…). Figure 1a The internal tissue protective sleeves 52 and 53 are housed within the outer sleeve component 51. The internal tissue protective sleeves 52 and 53 are... Figure 1cThe visible cross-section is constructed in an approximately U-shape, with the slots of the two internal tissue protection sleeves 52, 53 facing each other. The two openings in the U-shaped contours of the two internal tissue protection sleeves 52, 53 are constructed to resemble the opening regions 61, 62 of the opening 6 of the intramedullary nail 2, having a boundary region 54, such that when the intramedullary nail 2 moves substantially linearly within the medullary cavity, the drill wire 7 can move from the upper position to the lower position, and vice versa.

[0038] The construction of the opening 6 in the transition region 63 and the construction of the sleeve 5 with internal tissue protective sleeves 52, 53 (each having a corresponding opening in the transition region 63 or internal tissue protective sleeves 52, 53) relative to each other allow the drill wire 7 to be guided from an upper position to an lower position relative to the intramedullary nail 2, and vice versa. This provides multiple possibilities for adjustments during surgery based on specific circumstances. The following description first addresses the case where the first drill wire 7, which is actually intended for the bone screw 3, is positioned too low. It then explains how to perform correction for a drill wire 7 positioned too high for the bone screw 3.

[0039] Figures 2 to 6 This illustrates the correction process when the first drill wire 7 used for the bone screw 3 is positioned too distally in the femoral head. This is in Figure 2 The middle is obvious. Then, according to Figure 3 First, remove the guide sleeve 12 for drilling 7 that was inserted into the sleeve 5. This yields... Figure 3 The situation is shown below. Subsequently, according to... Figure 4 Clearly visible in the image is the proximal displacement of the intramedullary nail 2 along with the aiming module 11. Subsequently, according to... Figure 5 The guide sleeve 12 for drill wire 7 is then inserted again. The second drill wire 7 can then be inserted. As a result, the position of the first inserted drill wire 7 changes from above to below. In other words, the initially inserted drill wire 7—which has been confirmed to be too distal relative to the positioning of the subsequent bone screw 3—is not used as a drill wire 7 for determining the hole for the bone screw 3, but rather as a drill wire 7 for adjusting and / or fixing the screw 4.

[0040] Because the internal tissue protective sleeves 52 and 53 include holes 8, it becomes easier to correctly position the intramedullary nail 2 via linear displacement. For example, in Figure 1a or Figure 4 The clearly visible hole 8 is positioned so that the two internal tissue protection sleeves 52 and 53 are arranged along corresponding straight lines. This allows the use of imaging instruments typically used during surgery to identify the location of the drill wire 7 and align the internal tissue protection sleeves 52 and 53, making the drill wire 7 visible through the hole 8. This initially provides good alignment of the rest of the kit 1 relative to the inserted drill wire 7. Subsequent insertions of the drill wire 7 can then be precisely parallel to the first drill wire 7 and inserted into the femoral head.

[0041] Figures 7 to 13 The caudal correction is shown. The correction process is similar to the cranial correction, except that a drill wire 7 is removed. Figure 7 This illustrates the initial state of drill wire 7 (typically a K-wire) drilled too high. According to... Figure 8 Insert the second drill wire 7, i.e., the Kirschner wire. Afterwards, according to... Figure 9 Remove the upper drill wire 7, and then according to Figure 10 The guide sleeve 12 used for drill wire 7 is withdrawn. Thereafter, according to... Figure 11 The intramedullary nail 2, along with the aiming module 11, can be pushed distally, causing the unremoved drill wire 7 to move to the superior position. Therefore, the drill wire 7, initially located inferiorly for adjusting and / or fixing the screw 4, is now positioned for the bone screw 3. Subsequently, according to... Figure 12 and Figure 13 Specifically, a guide sleeve 12 can be inserted for another drill wire 7, and the second drill wire 7 can be inserted, which is now associated with the adjusting and / or fixing screw 4.

[0042] Figure 14 A correction sleeve 13 is shown. The correction sleeve 13 includes three openings 14 extending from the outside to the inside. All three openings 14 are constructed in the same manner on the inside. The openings 14 are used to guide the drill wire 7. The correction sleeve 13 can be laterally fixed to or inserted into the aiming module 1 or a sleeve component 51 already received therein. Minor misalignments of the drill wire 7 can be reliably corrected by the correction sleeve 13. See below for reference. Figures 15 to 23 This needs to be explained.

[0043] according to Figure 15 The drill wire 7, which was drilled slightly too high, has been positioned within the femoral head. Then, according to... Figure 16 Remove the Kirschner wire sleeve, i.e., the guide sleeve 12. Then, according to... Figure 17 Insert the calibration sleeve 13 without shifting the aiming module 11. Then, as... Figure 18 The second Kirschner wire is clearly visible in the image. Subsequently, according to... Figure 19 Remove the drill wire 7 above, and according to Figure 20 Remove the calibration sleeve 13. Afterwards, it can be done according to... Figure 21 The shift aiming module 11, according to Figure 22 Insert the guide sleeve 12, and according to Figure 23 Insert the second Kirschner wire, i.e., drill wire 7. Due to the small spacing between the channels 14 of the correction sleeve 13, very minor corrections can be made in this way for the subsequent precise positioning of the bone screw 3 and the adjusting and / or fixing screw 4.

[0044] at last, Figure 24The illustration shows a case where the bone screw 3, together with the adjusting and / or fixing screw 4, is positioned with the intramedullary nail 2 to achieve femoral neck fracture healing.

[0045] The kit 1 according to the invention enables correction during surgery for a femoral neck fracture, where the bone screw 3 bears the main load during the healing process, should an error in the positioning of the first drill wire 7 used for subsequent positioning of the bone screw 3 be confirmed. This applies both when the drill wire 7 used for subsequent positioning of the bone screw 3 is positioned too proximally and when the drill wire 7 is positioned too distally. Therefore, caudal and cranial corrections can be performed according to the specific circumstances.

Claims

1. A kit (1) for treating fractures, particularly for treating femoral neck fractures, comprising an intramedullary nail (2) having an opening (6) having a first opening region (61) for receiving a bone screw (3) and a second opening region (62) for receiving an adjusting and / or fixing screw (4) for the bone screw (3), wherein the first opening region (61) is connected to the second opening region (62) in a transition region (63), and optionally a multi-part sleeve (5) and a plurality of drill wires (7), characterized in that, The opening (6) of the intramedullary nail (2) at the transition region (63) is larger than the outer diameter of the drill wire (7).

2. The kit (1) according to claim 1, characterized in that, The first opening region (61) is configured to have a larger free inner diameter than the second opening region (62).

3. The kit (1) according to claim 1 or 2, characterized in that, The sleeve (5) is configured for inserting the bone screw (3) and the adjusting and / or fixing screw (4), wherein the region for the bone screw (3) is adjacent to the region for the adjusting and / or fixing screw (4), wherein the free diameter of the sleeve (5) or a portion thereof in the boundary region (54) between the bone screw (3) and the adjusting and / or fixing screw (4) is greater than the outer diameter of the drill wire (7).

4. The kit (1) according to claim 3, characterized in that, The sleeve (5) is configured as a multi-part sleeve having an outer sleeve component (51) and including an inner tissue protective sleeve (52, 53) housed in the outer sleeve component (51).

5. The kit (1) according to claim 4, characterized in that, The internal tissue protective sleeves (52, 53) are configured to have slots facing each other.

6. The kit (1) according to claim 5, characterized in that, The internal tissue protection sleeves (52, 53) are configured to be elongated and have a U-shape in a cross section transverse to the longitudinal axes (X, Y), wherein the opening regions of the tissue protection sleeves (52, 53) face each other.

7. The kit (1) according to any one of claims 1 to 6, characterized in that, The sleeve (5) or a portion thereof, particularly the tissue protection sleeve (52, 53), is configured to have a hole (8), wherein the hole (8) is preferably arranged in a straight line between the inner end (9) and the outer end (10).

8. The kit (1) according to any one of claims 1 to 7, characterized in that, The kit (1) includes an aiming module (11).

9. The kit (1) according to any one of claims 1 to 8, characterized in that, The kit (1) includes two drill wires (7) with the same construction.

10. The kit (1) according to any one of claims 1 to 9, characterized in that, The kit (1) includes a correction sleeve (13) for a plurality of drill wires (7), wherein the correction sleeve (13) includes a plurality of channels (14) for receiving the drill wires (7), and wherein the distance between the channels (14) is less than the distance between the center of the first opening region (61) and the center of the second opening region (62).

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