Bone fixation plate and method for manufacturing bone fixation plate

Abstract

The present invention provides a bone fixation plate for fixing bone fragments, and a method for manufacturing such a bone fixation plate. [Solution] A bone fixation plate (P) for fixing a bone fragment, comprising a long body (G) having an upper surface (G1) and a lower surface (G2) opposite to the upper surface (G1), the lower surface being provided for positioning the bone fixation plate on a bone fragment, the bone fixation plate having a plurality of openings for each receiving a screw, an integrally molded annular insert (R) being positioned in at least one of the openings, the insert comprising a first and a second portion, the first portion facing toward the upper surface and positioned directly adjacent to the second portion in the axial direction, the first portion having a non-rotationally symmetric outer contour, and the second portion having a rotationally symmetric outer contour.

Description

Technical Field

[0001] The present invention relates to a bone fixation plate for fixing bone fragments and a method for manufacturing such a bone fixation plate.

[0002] Bone fixation plates are used in human and veterinary medicine to fix bone fragments, for example after a fracture, in order to promote the fusion of the bone fragments in anatomically correct positions.

[0003] WO 2017 / 139903 teaches, for example, a bone fixation device having a bone plate with plate holes. A hollow cylindrical or hollow conical insert is mounted in the plate holes, and this insert is provided for receiving the head of a bone screw. The insert is arranged in the plate holes in a manner that is rotationally fixed due to an interlock connection, for example by means of projections on the inner wall of the plate holes and corresponding depressions of the insert.

[0004] EP 2 168 513 describes a bone fixation device having a plate with at least one through-hole. The plate has an insert around the through-hole, and this insert is made of a material that is softer than the plate. The insert and the plate are locked to each other and interconnected. According to the invention, the insert is not completely rotationally symmetric in order to fix the insert against rotation relative to the plate.

[0005] The technique of using such an insert or inlay in the plate allows for the use of a more ductile material in the region of the through-hole compared to the rest of the plate body. By using a more ductile material in the region of the through-hole, it is not necessary to pre-form a female thread, and the angular variation in the screwing direction is limited. However, the insert or inlay reduces the cross-section available in the body between the through-holes such that the number of through-holes is limited.

[0006] Therefore, the first problem addressed by the present invention is to provide a bone fixation plate distinguished by the requirement of the smallest possible insert installation space. A further problem addressed by the present invention is to provide a process-safe method for manufacturing such a bone fixation plate.

[0007] The first problem is solved by the features of claim 1. Further problems are solved by the features of claim 17. Preferred embodiments can be gathered from the dependent claims, specification, and drawings.

[0008] As a solution to the first problem, a bone fixation plate for fixing a bone fragment is provided, the bone fixation plate having an elongated body with an upper surface and a lower surface opposite to the upper surface. The lower surface is provided for positioning the bone fixation plate on the bone fragment. The bone fixation plate has a plurality of openings for receiving a screw, preferably a threaded screw head, each receiving a screw. An integrally molded annular insert is positioned in at least one of the openings. The insert has a first part and a second part that are positioned directly adjacent to each other in the axial direction. "Axial direction" in this case means the direction of the central axis of the insert. The first part faces the upper surface such that the second part faces the lower surface. The first part has a non-rotationally symmetric outer contour. The second part has a rotationally symmetric outer contour.

[0009] According to the present invention, by dividing the insert into a first portion having a non-rotationally symmetric outer contour and a second portion having a rotationally symmetric outer contour, the functions are distributed, with the first portion used to rotationally secure the insert to the body and the second portion used to axially secure the insert. This distribution of functions allows the cross-sections involved to be optimized for each task so as to minimize the installation space required for the insert.

[0010] Preferably, the rotationally asymmetric outer contour of the first portion of the insert is formed by at least six projections uniformly or non-uniformly distributed on the outer circumference of the insert. The term “projections” relates only to the shape and not to the manufacturing process. The at least six projections allow for particularly uniform force distribution during torque support of the insert against the body of the osteosynthesis plate, thereby allowing the required cross-section of the first portion of the insert to be kept small. A uniform distribution of projections along the outer circumference provides the advantage that the insert can be positioned within the body at different angular directions, thus simplifying the installation of the osteosynthesis plate. A non-uniform distribution of projections may be preferred when a predetermined angular direction of the insert during insertion into the osteosynthesis plate is desired. This is, for example, when the surface of the insert facing upward is color-coded in multiple colors. A predetermined angular position during mating is preferred to orient such color-coded inserts in the same way as one another.

[0011] According to a preferred embodiment, the non-rotationally symmetric outer contour of the first portion of the insert has exactly eight or exactly nine protrusions. This number has been proven in tests to be a good compromise between simple and reliable manufacturing, a compact design, and easy installation.

[0012] Preferably, the protrusions form a non-rotationally symmetric outer contour portion that is larger than the valleys extending between the protrusions in the circumferential direction. In other words, the valleys are narrower than the protrusions. As a result, the cross-section of the first portion of the insert is utilized particularly well.

[0013] Preferably, each projection has an arc-shaped portion whose center is located coaxially with the central axis of the insert. Such a projection shape improves the force distribution within the projection during torque support.

[0014] Preferably, the ratio of the minimum diameter of the portion positioned between the protrusions to the maximum diameter of the protrusions is greater than 0.8, preferably greater than 0.85, and particularly preferably greater than 0.9. Such a ratio allows the annular insert to be designed to have particularly thin walls.

[0015] According to a preferred embodiment, the non-rotationally symmetric outer contour has a wavy shape. Preferably, the transition portion extends tangentially between the wave peaks, i.e., protrusions and wave troughs. Such a protrusion shape improves the force distribution within the protrusion during torque support.

[0016] Preferably, the transition between the first and second portions of the insert is formed by a surface oriented perpendicular to the central axis of the insert. This surface can be used to fix the insert axially, for example, by the fact that the surface is located on a projection or step in the opening that is oriented radially inward of the opening.

[0017] In a preferred embodiment, the opening has a radially inwardly oriented projection having a first surface directed toward the upper surface of the osteosynthesis plate and a second surface directed toward the lower surface of the osteosynthesis plate. In this embodiment, the second portion of the insert is present on both the first and second surfaces in at least a portion of its area. In other words, the second portion engages with the projection from both sides so that the insert is axially fixed in both axial directions.

[0018] Preferably, the insert has a rotationally symmetric inner profile with a non-constant inner diameter. “Non-constant inner diameter” is understood in this context to mean that at least a portion of the inner profile has a non-constant diameter. The inner profile may have a piecewise constant diameter, but not across the entire axially extending portion of the inner profile.

[0019] The insert preferably has a first portion with a certain diameter. This first portion constitutes the minimum diameter of the inner contour. Once the screw connection between the bone fixation plate and the bone fragment is established, the threads of the bone screw, particularly the threads formed on the screw head, are molded into this first portion.

[0020] The inner contour preferably has a second portion extending from the first portion toward the upper surface of the bone fixation plate. Towards the lower surface of the bone fixation plate, the inner contour has a third portion. The second and third portions form an inner contour that is linearly tapered, having a first taper angle range in at least some areas. In other words, the inner contour has a recess on each of the two end faces of the first portion. As a result, the material flow that occurs when the threads are molded into the first portion is improved. The first taper angle range can be, for example, 10 to 30 degrees. The taper angle of the second portion may be the same as or different from the taper angle of the third portion.

[0021] Preferably, the medial contour has a further portion that extends from the second portion toward the upper surface of the osteosynthesis plate and forms a linearly tapered contour having a second taper angle range in at least a portion of it. Alternatively or in addition, the medial contour may have a further portion that extends from the third portion toward the lower surface of the osteosynthesis plate and forms a linearly tapered contour having a second taper angle range in at least a portion of it. The second taper angle range is steeper than the first taper angle range, for example, 50 to 80 degrees.

[0022] The opening for receiving the insert preferably has at least one portion with a non-rotationally symmetric inner contour. This portion is formed so that a first portion of the insert can be received in a manner that is rotationally fixed to the non-rotationally symmetric inner contour of the opening.

[0023] According to another embodiment, the opening for receiving the insert has at least one portion having a rotationally asymmetric inner contour which is formed such that a rotationally asymmetric outer contour of a first portion of the insert is formed when the insert is press-fitted into the opening. This is achieved, for example, by the tooth shape of the rotationally asymmetric inner contour portion of the opening. The teeth may have a trajectory in the direction of the upper surface of the bone fixation plate so that uniform forming of the rotationally asymmetric outer contour of the insert is achieved.

[0024] Preferably, the osteosynthesis plate has multiple circular openings, in which case one insert is placed in each of the circular openings as described above. The osteosynthesis plate may also have non-circular openings, such as elongated holes. Placing one insert in each circular opening facilitates the use of the osteosynthesis plate, as the surgeon does not need to consider different instructions for using the circular openings. As a solution to further challenges, a method for manufacturing the aforementioned bone fixation plate is provided, which involves the following steps: The steps include preparing the main unit and at least one insert, The steps include: pressing or inserting an insert into one of the openings of the main body from the top surface of the main body; The steps include: reshaping at least one area of ​​the second portion of the insert from the underside of the body in order to establish an interlocking connection between the insert and the body; It holds.

[0025] Such a method allows the insert to be secured in the opening in a process-safe and reliable manner.

[0026] In the step of "press-fitting or inserting the insert," the originally rotationally symmetrical region of the insert is preferably shaped to form the rotationally symmetrical outer contour of the insert. In other words, the rotationally symmetrical outer contour of the first portion of the insert is initially formed during the process of joining the insert to the opening. This reduces the manufacturing effort required to produce the insert.

[0027] According to an alternative embodiment, the step of "providing at least one insert" includes the step of creating a non-rotationally symmetric outer contour of the first part of the insert. In other words, the non-rotationally symmetric outer contour of the insert does not occur first during the process of joining the insert to the aperture, but rather already occurs during the manufacture of the insert itself. The non-rotationally symmetric outer contour of the first part of the insert can be formed, for example, by material removal machining, sintering, or rolling.

[0028] The body of the bone fixation plate is preferably made of a titanium alloy or a steel alloy. The one or more inserts are preferably made of a titanium alloy or pure titanium, such as grade 2 titanium. The body and / or the one or more inserts can be surface treated, for example anodized. The one or more inserts can have different surface treatments, for example, for different color labels of compatible screws.

[0029] Typical embodiments of the present invention will be described in detail based on the drawings.

Brief Description of the Drawings

[0030] [Figure 1] An isometric view of a bone fixation plate according to a first embodiment is shown. [Figure 2] An isometric view of a bone fixation plate according to a first embodiment is shown. [Figure 3] An isometric view of a bone fixation plate according to a first embodiment is shown. [Figure 3b] An isometric view of a bone fixation plate according to a first embodiment with screws is shown. [Figure 4] A detailed view of a bone fixation plate according to a first embodiment is shown. [Figure 5] A detailed view of a bone fixation plate according to a first embodiment is shown. [Figure 6] A detailed view of a bone fixation plate according to a first embodiment is shown. [Figure 7] A top view of an insert according to a first embodiment is shown. [Figure 8]A cross-sectional view of the insert according to the first embodiment is shown. [Figure 9] A cross-sectional view of a bone fixation plate with an alternative embodiment of the insert is shown. [Figure 10] A cross-sectional view of a bone fixation plate with an alternative embodiment of the insert is shown. [Figure 11] A detailed cross-sectional view of the insert according to the first embodiment is shown. [Figure 12] A detailed view of the opening of the bone joint plate according to the first embodiment is shown. [Figure 13] This diagram shows the process of joining an insert to the main body of a bone fixation plate according to the first embodiment. [Figure 14] The diagrams show different processes for joining an insert to the body of a bone fixation plate according to the first embodiment. [Figure 15] The diagrams show different processes for joining an insert to the body of a bone fixation plate according to the first embodiment. [Figure 16] The diagrams show different processes for joining an insert to the body of a bone fixation plate according to the first embodiment. [Figure 17] The diagrams show different processes for joining an insert to the body of a bone fixation plate according to the first embodiment. [Figure 18] The diagrams show different processes for joining an insert to the body of a bone fixation plate according to the first embodiment. [Figure 19] A detailed diagram of the bone fixation plate according to the second embodiment is shown. [Figure 20] A detailed diagram of the bone fixation plate according to the second embodiment is shown. [Figure 21] A detailed diagram of the bone fixation plate according to the second embodiment is shown. [Figure 22] A cross-sectional view of the bone fixation plate according to the second embodiment is shown. [Figure 23] A cross-sectional view of the bone fixation plate according to the second embodiment is shown. [Figure 24] A cross-sectional view of the bone fixation plate according to the second embodiment is shown.

[0031] Figure 1 shows an isometric view of a bone fixation plate P according to a first embodiment. The bone fixation plate P is used to fix bone fragments (not shown) and is designed, for example, to be applied to the proximal humerus. The bone fixation plate P has an elongated body G with an upper surface G1 and a lower surface G2 opposite to the upper surface G1. The lower surface G2 is provided for positioning the bone fixation plate P on the bone fragment. In the diagram relating to Figure 1, the left is the proximal side and the right is the distal side. The bone fixation plate P has a plurality of circular openings A, each designed to receive one screw SK. The bone fixation plate P can be fixed to the bone by screws SK to fix the bone fragments relative to each other in a desired position. Due to natural bone fixation, new bone material is formed in the area of ​​one or more gaps between the bone fragments. The bone fixation plate P also has elongated holes LL, which are also designed to receive screws SK. The bone fixation plate P has a plurality of suture anchors N so that soft tissue, for example, one or more tendons can be fastened to the bone fixation plate P. The top surface G1 is provided with a blind hole BA with a female thread for attaching a drill guide block (not shown in Figure 1). The main body G is made of a metal suitable for use in medical technology, such as titanium alloy or stainless steel.

[0032] Figure 2 shows a bone fixation plate P with associated inserts R. Each insert R is assigned one of the circular openings A. The inserts R are integrally molded and annular. The inserts R are made of a metal suitable for use in medical technology, which has higher ductility than the material of the body G, for example, a corresponding ductile titanium alloy or pure titanium. As shown in Figure 2, the axes of the openings A for receiving the inserts R are oriented differently to result in pre-alignment of the threads SK. The shape of the inserts R allows for the orientation of the threads SK to deviate from this pre-alignment. The slotted holes LL are not associated with the inserts. The slotted holes LL are designed so as to define the angular direction of the threads SK associated with the slotted holes LL. Figure 3 shows a bone fixation plate P with the inserts R positioned within the openings A.

[0033] Figure 3b shows a further diagram of the bone fixation plate P, in which one screw SK is positioned in each of the circular openings A and the elongated hole LL. The screw SK has a screw head with male threads (not visible in Figure 3b) that is received in the openings A and the elongated hole LL.

[0034] Figure 4 shows a detailed exploded view of the osteosynthesis plate P to visualize the acceptance of the insert R into the opening A during the process of assembling the osteosynthesis plate P. For clarity, parts of the main body G and insert R are shown in cutaway. The opening A has a non-rotationally symmetric inner contour AD and a projection AK directed radially inward. The projection AK has a first surface AK1 directed toward the upper surface G1 and a second surface AK2 directed toward the lower surface G2. The insert R has a first portion R1 and a second portion R2. The first portion R1 is directed toward the upper surface G1 and has a non-rotationally symmetric outer contour AD1 in the form of multiple radial projections E1 distributed on its outer circumference. The second portion R2 is directed toward the lower surface G2 and has a rotationally symmetric outer contour AD2. The insert R has a surface RF oriented perpendicular to the central axis RA of the insert R.

[0035] Figure 5 shows a detailed view of the osteosynthesis plate P with the insert R inserted into the opening A such that the surface RF is positioned on projection AK. The rotationally asymmetric outer contour AD1 of the insert R is inserted into the rotationally asymmetric inner contour AD of the opening A, and this inner contour is formed to complement the outer contour. As a result, the insert R is rotationally fixed to the body G. A second portion R2 of the insert R protrudes toward the lower surface G2 beyond the second surface AK2 of projection AK.

[0036] Figure 6 shows a detailed view of the bone fixation plate P, in which the insert R is inserted into the opening A, and the second portion R2 is reshaped such that at least a part of the second portion R2 is located on the second surface AK2, thereby surrounding the projection AK by both end faces. This fixes the insert R axially to the main body G.

[0037] Figure 7 shows a top view of the insert R, with the first portion R1 of the insert R visible. The rotationally symmetric outer contour AD1 of the first portion R1 is formed by nine radial projections E1 uniformly distributed on the outer circumference. The rotationally symmetric outer contour AD1 has a wavy shape, with the radial projections E1 alternating with the valleys T1. The transitions between the projections E1 and the valleys T1 extend tangentially. The projections E1 form portions of the rotationally symmetric outer contour AD1 that are larger than the valleys T1. Each projection E1 has an arc-shaped portion E1K whose center is coaxial with the central axis RA of the insert R. The projections E1 are uniformly distributed on the outer circumference such that each projection E1 is offset by the same angle E1W. The ratio of the minimum diameter MIN of the valleys T1 to the maximum diameter MAX of the projections E1 is greater than 0.9.

[0038] Figure 8 shows a cross-sectional view of insert R, in which case the second portion R2 of insert R has already been reshaped as shown in Figure 6 in order to fix insert R axially to the main body G. In Figure 8, it is clear that insert R has a rotationally symmetric inner contour ID with a non-constant inner diameter. The inner contour ID has a first portion ID1 with a constant diameter that forms the minimum diameter of the inner contour ID. When the bone joint plate P is fastened to the bone fragment using a screw SK, the male threads of the screw head form threads in the first portion ID1. The inner contour ID has a second portion ID2 extending from the first portion ID1 in the direction of the upper surface G1. The second portion ID2 forms an inner contour that is formed in a linearly tapered manner. The inner contour ID has a third portion ID3 extending from the first portion ID1 in the direction of the lower surface G2. The third portion ID3 forms an inner contour that is formed in a linearly tapered manner. Portions ID2 and ID3 form a relatively flat taper angle to improve the flow behavior of insert R during thread formation. The inner contour ID has a fourth portion ID4 extending from a second portion ID2 toward the upper surface G1. The fourth portion ID4 forms an inner contour that is formed in a linear tapered shape. The inner contour ID has a fifth portion ID5 extending from a third portion ID3 toward the lower surface G2. The fifth portion ID5 forms an inner contour that is formed in a linear tapered shape. The inner contour ID of the insert R allows the screw SK to be fixed at different angles with respect to the central axis RA of the insert R.

[0039] Figure 9 shows a cross-sectional view of the osteosynthesis plate P with an alternative embodiment of insert R. Compared to the embodiment shown in Figure 8, insert R does not have a fourth portion ID4. Instead, the second portion ID2 extends to the end face of insert R facing the upper surface G1 of the osteosynthesis plate P.

[0040] Figure 10 shows a cross-sectional view of the bone fixation plate P with a further alternative embodiment of the insert R. Compared to the embodiment shown in Figure 9, the insert R does not have a fifth portion ID5. Instead, the third portion ID3 extends to the end face of the insert R facing the lower surface G2 of the bone fixation plate P.

[0041] Figure 11 shows a detailed view of insert R for indicating the inner contour ID in the region of the first portion ID1. Insert R is designed as shown in Figure 8. From the diagram in Figure 11, it is clear that tapered portions ID2 and ID3 directly adjacent to the first portion ID1 have a flatter taper angle range W1 than tapered portions ID4 and ID5 adjacent to them, which have a steeper taper angle range W2.

[0042] Figure 12 shows a detailed view of the opening A and projection AK to indicate the non-rotationally symmetric inner contour AD. The non-rotationally symmetric inner contour AD has a radially inwardly oriented projection ADE that protrudes between the cylindrical portions ADT. The opening A extends from the non-rotationally symmetric inner contour AD and has a cylindrical portion AZ in the direction of the upper surface G1. The surface AK1 of projection AK, which faces the upper surface G1, is directly adjacent to the non-rotationally symmetric inner contour AD.

[0043] Figures 13 to 18 show different diagrams of the process of joining the insert R to the main body G of the bone fixation plate P. In the diagram relating to Figure 13, the main body G and the insert R are positioned between two tools M1 and M2. In the diagram relating to Figure 14, the insert R is inserted into the opening A of the main body G, thereby allowing the non-rotationally symmetric outer contour AD1 to be received by the complementary non-rotationally symmetric inner contour AD. In the diagram relating to Figure 15, the insert R is press-fitted into the opening A by tool M1 so that the insert R is positioned on a projection AK directed radially inward. In the diagram relating to Figure 16, tool M2 is guided from the lower surface G2 toward the second portion R2 of the insert R so that tool M2 is positioned on the insert R. In the diagram relating to Figure 17, the second portion R2 of the insert R is reshaped by tool M2 so that the radially inward projection AK is surrounded by both end faces of the insert R. The insert R is held in place by tool M1 toward the upper surface G1. Figure 18 shows the fully mated insert R after the tools M1 and M2 have been released.

[0044] Figure 19 shows a detailed view of the bone fixation plate P according to the second embodiment. The non-rotationally symmetric inner contour ID of the opening A has a step AS that forms a tooth. The insert R does not yet have a rotationally symmetric outer contour in the non-fitted state shown in Figure 19. Instead, the insert R is rotationally symmetric in the non-fitted state.

[0045] Figure 20 shows a detailed view of a bone fixation plate P according to a second embodiment, in which an insert R is inserted into the body G of the bone fixation plate P. Insertion of the insert R into the teeth of the step AS forms a non-rotationally symmetric outer contour AD1 on the first portion R1 of the insert R. The second portion R2, which is spatially lower, has a smaller diameter and is therefore not reshaped by the teeth of the step AS.

[0046] Figure 21 shows a detailed view of a bone fixation plate P according to a second embodiment, in which the insert R is fully fitted into the body G of the bone fixation plate P. The second portion R2 is then reshaped so that the second portion R2 surrounds the surface of the step AS, which is oriented toward the lower surface G2. This fixes the insert R axially to the body G.

[0047] Figures 22 to 24 show different cross-sectional views of a portion of the bone fixation plate P according to the second embodiment, during the fitting of the insert R into the main body G, although tools are not shown. Figure 22 shows the state in which the insert R has not yet been fitted into the main body G. The stepped AS on which the teeth are formed is clearly visible in Figure 22. Figure 23 shows the state in which the insert R has been inserted into the main body G so that an as-rotationally symmetric outer contour AD1 is formed on the first portion R1 of the insert R. In this state, the second portion R2 has not yet been reshaped. Figure 24 shows the state in which the second portion R2 of the insert R has been reshaped so that a surface RF is formed in the transition area between the first portion R1 and the second portion R2. The surface is oriented perpendicular to the central axis RA of the insert R and is located on the end face of the stepped AS facing the lower surface G2.

[0048] The inner contour ID of insert R according to the second embodiment corresponds, for example, to the inner contour ID of insert R according to the first embodiment (shown in Figure 8). This is shown only as an example. The inner contour ID of insert R according to the second embodiment can also be designed as shown in Figure 9 or Figure 10. [Explanation of Symbols]

[0049] P...Bone fixation plate, SK...Screw, G...Main body, G1...Top surface, G2...Bottom surface, N...Suture anchor, BA...Blind hole, A...Opening, AK...Projection, AK1...First surface, AK2...Second surface, AD...Non-rotationally symmetrical inner contour, ADE...Projection, ADT...Cylindrical part, AZ...Cylindrical part, AS...Step, LL...Slotted hole, R...Insert, RA...Central axis, R1...First part of insert, AD1...Non-rotationally symmetrical outer contour, E1...Projection, E1W...Angle, MIN...Minimum diameter, MAX...Maximum diameter, E1K...Arc-shaped part, T1...Valley, R2...Second part of insert, AD2...Rotationally symmetrical outer contour, RF...Surface, ID...Inner contour, ID1...First part, ID2...Second part, ID3...Third part, ID4, ID5...Further parts, W1...First taper angle range, W2...Second taper angle range, M1, M2...Tool.

Claims

1. A bone fixation plate (P) for fixing a bone fragment, wherein the bone fixation plate (P) comprises a long body (G) having an upper surface (G1) and a lower surface (G2) opposite to the upper surface (G1), and the lower surface (G2) is provided for positioning the bone fixation plate (P) on the bone fragment. The bone fixation plate (P) is provided with a plurality of openings (A) for receiving one screw (SK) each, A integrally molded annular insert (R) is positioned in at least one of the openings (A), and the insert (R) comprises first and second portions (R1, R2), wherein the first portion (R1) faces toward the upper surface (G1) and is positioned directly adjacent to the second portion (R2) in the axial direction. The first portion (R1) has a non-rotationally symmetric outer contour (AD1), and the second portion (R2) has a rotationally symmetric outer contour (AD2), Bone fixation plate (P).

2. The bone fixation plate (P) according to claim 1, characterized in that the non-rotationally symmetric outer contour (AD1) is formed by at least six, preferably exactly eight or exactly nine, radial projections (E1) uniformly or non-uniformly distributed on the outer circumference.

3. The bone fixation plate (P) according to claim 2, characterized in that the projections (E1) form a portion of the non-rotationally symmetric outer contour (AD1) that is larger than the valleys (T1) extending circumferentially between the projections (E1).

4. The bone fixation plate (P) according to claim 2 or 3, characterized in that each of the projections (E1) is provided with an arc-shaped portion (E1K), and the center of the arc-shaped portion (E1K) is arranged coaxially with the central axis (RA) of the insert (R).

5. The bone fixation plate (P) according to any one of claims 2 to 4, characterized in that the ratio between the minimum diameter (MIN) of the portion disposed between the projections (E1) and the maximum diameter (MAX) of the projections (E1) is greater than 0.8, preferably greater than 0.85, and particularly preferably greater than 0.

9.

6. The bone fixation plate (P) according to any one of claims 1 to 5, characterized in that the non-rotationally symmetric outer contour (AD1) has a wavy shape.

7. The bone fixation plate (P) according to any one of claims 1 to 6, characterized in that the transition between the first and second portions (R1, R2) of the insert (R) is formed by a surface (RF) perpendicular to the central axis (RA) of the insert (R).

8. The bone fixation plate (P) according to claim 7, characterized in that the surface (RF) is located on a projection (AK) directed radially inward of the opening (A) or on a step (AS) of the opening (A).

9. The bone fixation plate (P) according to any one of claims 1 to 8, wherein the opening (A) comprises a radially inwardly oriented projection (AK) having a first surface (AK1) directed toward the upper surface (G1) of the bone fixation plate (P) and a second surface (AK2) directed toward the lower surface (G2) of the bone fixation plate (P), and the second portion (R2) of the insert (R) is located on both the first surface (AK1) and the second surface (AK2) in at least a portion of the area.

10. The bone fixation plate (P) according to any one of claims 1 to 9, characterized in that the insert (R) has a rotationally symmetric inner contour (ID) with an inconsistent inner diameter.

11. The bone fixation plate (P) according to claim 10, characterized in that the inner contour (ID) of the insert (R) comprises a first portion (ID1) having a constant diameter that constitutes the minimum diameter of the inner contour (ID).

12. The bone fixation plate (P) according to claim 11, wherein the inner contour (ID) comprises a second portion (ID2) extending from the first portion (ID1) toward the upper surface (G1) of the bone fixation plate (P), and a third portion (ID3) extending from the first portion toward the lower surface (G2) of the bone fixation plate (P), and the second and third portions (ID2, ID3) form an inner contour that is formed in a linearly tapered shape having a first taper angle range (W1) in at least a portion of the region.

13. The bone fixation plate (P) according to claim 12, wherein the inner contour (ID) comprises a further portion (ID4) extending from the second portion (ID2) toward the upper surface (G1), and / or a further portion (ID5) extending from the third portion (ID3) toward the lower surface (G2), wherein the further portion forms a contour that is linearly tapered having a second taper angle range (W2) in at least a portion of the region, and the second taper angle range (W2) is steeper than the first taper angle range (W1).

14. The bone fixation plate (P) according to any one of claims 1 to 13, characterized in that the opening (A) for receiving the insert (R) comprises at least one portion having a rotationally asymmetric inner contour (AD) such that the first portion (R1) of the insert (R) is rotatably fixed to the rotationally asymmetric inner contour (AD) of the opening (A).

15. The bone fixation plate (P) according to any one of claims 1 to 13, characterized in that the opening (A) for receiving the insert (R) comprises a portion having a rotationally symmetric inner contour (AD) such that the first portion (R1) of the insert (R) can be molded during the process of press-fitting the insert (R) into the opening (A).

16. The bone fixation plate (P) according to any one of claims 1 to 15, characterized in that the bone fixation plate (P) comprises a plurality of circular openings (A), and one of the inserts (R) is positioned in each of the circular openings (A).

17. A method for manufacturing a bone fixation plate (P) according to any one of claims 1 to 16, The steps include preparing the main body (G) and the at least one insert (R), The steps include press-fitting or inserting the insert (R) into one of the openings (A) of the main body (G) from the upper surface (G1) of the main body (G), The steps include: in order to establish an interlock connection between the insert (R) and the body (G), reshaping at least one region of the second portion (R2) of the insert (R) from the lower surface (G2) of the body (G); A method characterized by including the following.

18. The method according to claim 17, characterized in that, in the step of "press-fitting or inserting the insert (R)", the originally rotationally symmetric region of the insert (R) is molded to form the rotationally symmetric outer contour (AD1) of the insert (R).

19. The method according to claim 17, characterized in that the step of "preparing the at least one insert (G)" includes the step of creating the non-rotationally symmetric outer contour (AD1) of the first portion (R1) of the insert (R).

Images