Implant for treating bones

Abstract

The invention relates to an implant (1) for treating bones, in particular for covering defects or drill holes or for reconstructing bone defects or malformations. The implant comprises at least one frame structure (2) and at least one adaptation region (3). The edge of the implant (4) is partly, but not continuously, formed by the frame structures (2) that are outside the adaptation region (3).

Description

Implant for the Treatment of Bone The invention relates to an implant for the treatment of bone with the features of the generic term of the independent claim. It is known that bone fractures, especially of the human skull, can be treated with implants. The aim of the treatment and im- plantation of an implant is generally to restore and maintain the anatomically correct shape and position of the bones to be treated and their surroundings. This promotes the healing pro- cess and preserves the functionality of the affected body part after healing has taken place. In the prior art, various implants are known that are adapted to specific parts of the body. EP 2 030 596 discloses an implant for the treatment of fractures of the orbit. These include a planar fitting area and a frame structure. US 5,139,497 discloses an orbital floor implant having a frame structure and a grid. US 2007 / 0238069 discloses cuttable and deformable meshes for the treatment of facial fractures. However, known implants have various disadvantages. For example, certain implants are equipped with frame structures that are adapted to specific bone areas. However, this sometimes makes implant placement difficult, especially since the exact anatomy of people naturally varies. At the same time, however, a certain degree of adaptation to the anatomy is desirable. It is therefore the task of the present invention to avoid the disadvantages of the prior art, in particular to provide an im- plant which on the one hand is adapted to the anatomy of the body part to be treated but at the same time allows certain ad- aptations. According to the invention, these and other tasks are solved with an implant according to the independent claim. The implant according to the invention is particularly suitable for covering defects or drill holes or for reconstructing bone defects or malformations. It comprises at least one frame struc- ture and a sheetlike adaptation area. The frame structure is ar- ranged outside the adaptation area. It partially forms the edge of the implant. The frame structure does not, however, complete- ly define the outer edge. This means that at least one area of the outer edge is not limited by the frame structure. This al- lows the frame structure of the implant to be adapted to a de- sired anatomy. At the same time, the adaptation area not limited by the frame structure allows cutting or deformation and thus further adaptation to the anatomy. A frame structure is to be understood as a region of the im- plant, in particular an edge region, which is designed by means of di-mensioning and / or by material selection and / or shaping in such a way that a minimum force required for plastic deformation of the edge region, in particular preferably the edge region and the adaptation area together, is higher than a minimum force re- quired for plastic deformation of the adaptation area. This property is referred to here and in the following as bendabil- ity. A smaller bendability of a part therefore means that a larger force must be applied to plastically deform it. A greater bendability of a part means that a smaller force is sufficient to deform it plastically. Accordingly, the frame structure may be less bendable compared to the adaptation area. Additionally or alternatively, a frame structure can also be a region of the implant, in particular an edge region, which interrupts the pe- riodicity of the lattice. The implant according to the invention is particularly suitable for the treatment of the human frontal sinus and is shaped and dimensioned accordingly. However, it can of course also be used for other parts of the body if the size and shape are suitable. Particularly preferably, the implant is mirror-symmetrical along a mirror plane. Preferably, the implant comprises at least two frame structures. These are both arranged outside the adaptation area and thus partially form the edge of the implant. The two frame structures do not continuously delimit the outer edge of the implant. As a result, at least two areas of the outer edge are not bounded by the frame structure. In particular, this allows adaptation to bones that have two similar and / or symmetrical regions, with the intermediate region varying from person to person. For example, the two frame structures may be adapted to the areas around the eyes and have an adaptation area to adapt to the nasal bone. Preferably, the adaptation area is continuous and is free of frame structures on the inside. Preferably, the frame structure is dimensioned and arranged such that at least half of the outer edge is not bounded by the frame structure. In the present case, half of the outer edge means half of the length of the outermost edge of the implant. Preferably, the adaptation area comprises a grid structure. The grid structure is dimensioned in such a way that it can be de- formed by hand or with hand tools. In particular, the adaptation area can be designed so that its bendability is adapted appro- priately. In particular, to this end, the adaptation area may be made of or comprise a material having an strain at failure of at least 5%, preferably at least 10%, more preferably at least 15%. Likewise, the adaptation area can be at least partially dimen- sioned so that at most a force of 300 N, preferably at most 150 N, particularly preferably at most 50 N, is required to achieve plastic deformation of the adaptation area, in particular a force acting vertically on the adaptation area. For example, the adaptation area can have wire- or rod-shaped elements with a ar- ea moment of inertia or material properties to achieve such de- formabilities. Depending on the material properties, the dimen- sions or area moments of inertia of the rod-shaped elements can be different in order to achieve the same deflection for the same force. Similarly, it is conceivable to make the thickness of the adaptation area such that a maximum force, in particular a maximum force listed above, is sufficient to achieve plastic deformation. In particular, the adaptation area can be at most 2 mm, preferably at most 1 mm, especially preferably at most 0.6 mm thick. Particularly preferably, the adaptation area has a thickness of 0.25 mm, 0.4 mm or 0.6 mm. Preferably, the implant comprises a biocompatible material, in particular from the group of implant steel and / or other metals, ceramics and plastics. Particularly preferably, the implant com- prises titanium or a titanium alloy. Preferably, the adaptation area has connection areas that are dimensioned so that they can be cut through using hand tools. This allows a surgeon to easily cut the adaptation area to fit the patient's anatomy. In particular, the connection areas can be designed as described above in relation to the adaptation area. The adaptation area preferably comprises a structure of holes whose circumferential areas are connected to each other via con- nection areas. In particular, the connection areas can be de- signed as ribs that connect the peripheral areas of the holes at regular intervals along their circumference. Preferably, the implant has a side length in a range of 10-200 mm. Alternatively, the side length may be in a range of 30-70 mm, or 25-50 mm. In particular, the implant may have an approxi- mately square shape with rounded corner regions. Particularly preferably, the frame structure is arranged in two adjacent rounded corner regions. Preferably, at least one frame structure is dimensioned and po- sitioned such that it can be attached, in particular screwed, to the margo supraorbitalis. To this end, the frame structure may have at least one, prefera- bly two, regions that correspond substantially in shape, curva- ture and / or size to the margo supraorbitalis. For example, the frame structure may have a radius in this region that has a de- viation of at most + / -30%, preferably at most + / -20%, particu- larly preferably at most + / -10% to the radius of the orbit. It is also possible for this region of the frame structure to have a radius that substantially corresponds to the radius of the or- bit (i.e. has an approximately equal radius). Particularly preferably, the radius of this region is substantially the same as the radius of the orbit. Further, these regions may have a length that is at most equal to the diameter of the human orbit. For example, the length may be at most 80 mm, preferably at most 60 mm, particularly preferably at most 50 mm. Preferably, the frame structure has an arc shape. In particular, the arc shape may have a radius of curvature of 10-200 mm, more preferably 10-80 mm. The radius of curvature may vary along re- gions of the frame structure. For example, the radius of curva- ture may increase continuously along an edge structure so that the frame structure forms the shape of a clothoid. Particularly preferably, the implant has an intermediate region. This is arranged between the two frame structures adapted to the margo orbitalis and can have a greater bendability than the two frame structures. Likewise, it is conceivable that the intermediate region thereby has in particular a length which essentially corresponds to the inner distance between two eye sockets of the human skull and / or the width of a human nose and / or the typical anatomical distance between the human lacrimal glands. Preferably, the connecting piece has a length of 0.5 to 4 cm, particularly preferably of 1 to 2 cm. Preferably, the implant has at least one attachment tab. Alter- natively, the implant can also have at least two attachment tabs. In particular, the attachment tab may be located at the edge of the implant or on a frame structure. Preferably, the at- tachment tab also has screw holes. This allows the implant to be fixed in a particularly advantageous manner, for example to be screwed to a bone. Preferably, the fixing tab extends away from the edge of the implant in the same plane as the implant, in particular at an azimuth angle between 70° and 95° with respect to the edge. In particular, if the edge of the implant is not straight at the point where a fastening tab is located, the azi- muth angle specification should be understood as the angle be- tween the fastening tab and a tangent to the edge of the implant at the point where the fastening tab is located. Particularly preferably, two attachment tabs extend away from the implant such that there is an acute angle between the attachment tabs that opens away from the implant. Additionally or alternatively, one or more attachment tabs may also be arranged so that they do not lie in the same plane as the implant, as the edge of the implant, or as the adaptation area of the implant and therefore lie at an elevation angle to said plane. In particular, the attachment tab may be angled away from the plane in which at least the edge of the implant and / or a frame structure lies. It is understood that implants are also conceivable which are not flat but have a free form. In particular, the implant can have local bends between planar elements, and / or have a shape of a rotational or translational surface. In this case, the afore- mentioned plane refers to a tangent surface to the surface of the implant at the location where the tab is attached. In par- ticular, for tabs that are not in the same plane as the tangent surface, an elevation angle can therefore be measured between the tab and its projection on the tangent surface. An azimuth angle can be measured in the tangent plane between the tab and a tangent to the edge of the implant. In particular, the at least one attachment tab may be integrally connected to the frame structure. The implant can also have at least two attachment tabs that are integrally connected to the frame structure. If the implant also has at least two frame structures, the at least two attachment tabs are preferably in- tegrally connected to one frame structure each. However, it is also possible for more than one attachment tab to be integrally connected to the same frame structure. Alternatively, however, it is also possible to arrange one or more attachment tabs at the edge of the implant without connect- ing them to the frame structure. In particular, one or two at- tachment tabs can be arranged between two frame structures. This is particularly advantageous if at least one frame structure is dimensioned and positioned in such a way that it can be at- tached, in particular fastened with screws, to the margo supra- orbitalis. Preferably, the at least one attachment tab is adapted for at- tachment to the nasal bone. The adaptation can be achieved in particular by the dimension, shape, and positioning on the im- plant. If the implant has at least two attachment tabs, prefera- bly at least two attachment tabs are also adapted in the same way for attachment to the nasal bone. In particular, the attachment tabs may have a length substan- tially equal to the length of the human nasal bone. For example, the attachment tabs can have a length of at most 3 cm, prefera- bly at most 2 cm, particularly preferably at most 1.5 cm. Two attachment tabs may be arranged relative to each other such that their smallest distance corresponds to the width of the nasal bone. For example, the distance can be about 5 - 30 mm. Prefera- bly, the attachment tabs are not arranged parallel to each other in this case. However, it is possible for the attachment tabs to be arranged in a plane at an angle greater than or less than 0°. Attachment tabs that are interlaced about their longitudinal ax- is are also conceivable. If an implant has one or two areas adapted for attachment to the margo supraorbitalis, the attachment tabs can in particular be arranged at these areas. Preferably, one attachment tab is ar- ranged on each of the areas adapted for attachment to the margo supraorbitalis. Particularly preferably, the attachment tabs ar- ranged at the regions adapted for attachment to the margo supra- orbitalis face each other. In this case, the implant may in particular be mirror symmetrical along a plane and / or axis sub- stantially between the two attachment tabs and / or regions adapted for attachment to the margo supraorbitalis. However, non-mirror symmetrical designs are also conceivable. Preferably, the adaptation area is formed in integrally. Preferably, the entire implant is formed integrally. Preferably, the implant is adapted to cover defects or burr holes or to reconstruct bone defects or malformations on the si- nus. Preferably, the adaptation area is plastically deformable. In particular, the adaptation area can be dimensioned or adapted in the choice of material so that plastic deformation is possible. The invention is explained in more detail below with reference to the figures and embodiments, showing: Fig. 1: an embodiment of an implant according to the invention, Fig. 2: an alternative embodiment of an implant according to the invention, Pig. 3% a further alternative embodiment of an implant accord- ing to the invention, Fig. 4: an enlarged representation of a fitting area, Fig. 5: an alternative embodiment of an implant according to the invention. Fig. .. shows an embodiment of an implant 1 according to the in- vention, which is adapted in shape and size to be implanted in the region of the human frontal sinus. The implant comprises two frame structures 2 and an adaptation area 3. The outer edge of the implant is symbolized by a dashed line 4 and is to be under- stood here and in general as the outermost boundary of the en- tire implant before any cutting. The two frame structures 2 par- tially form the outer edge 4 of the implant. In particular, the frame structures 2 here have an arcuate shape and are adapted in shape and dimension to the human margo supraorbitalis. Further, they comprise screw holes 10 suitable for receiving screws so that the implant 1 can be screwed to a bone. The implant further comprises two attachment tabs 8, each of which is integrally connected to one of the frame structures 2. In the present case, the attachment tabs 8 are connected at the facing ends of the frame structures 2 between the two frame structures and extend in the same plane as the implant at an angle of approximately 85° away from the implant. Thus, the attachment tabs 8 corre- spond to the position of the nasal bone when the frame struc- tures are attached to the margo supraorbitalis. Further, the at- tachment tabs include screw holes 10a suitable for screwing the attachment tabs to the nasal bone. Between the two frame struc- tures 2 and attachment tabs is an intermediate region 5a, which has no frame structure. This corresponds in its design to the remaining edge region 5b of the implant and is designed in par- ticular in such a way that it has greater bendability than the frame structure.. Thus, the force required to cause plastic de- formation of the intermediate region 5a is relatively small and can be applied by hand or hand tools. In the present case, the implant comprises only frame structures adapted to the region of the margo supraorbitalis, which can be attached to the nasal bone via attachment tabs. The remainder 5b of the outer edge 4 is not bounded by frame structures and can therefore be trimmed by the surgeon. This allows, for example, the implant to be adapted to a smaller area of a patient's anatomy. In addition, the adaptation area 3 is plastically deformable, so that further adaptation possibilities exist. Fig. 2 shows an alternative embodiment of an implant 1 according to the invention. The embodiment shown here comprises only one frame structure 2. The frame structure partially delimits the outer edge 4, so that a part 5 of the outer edge is formed with- out a frame structure. The sheetlike adaptation area 3 has es- sentially the same design as that shown in Fig. 1, and is there- fore plastically deformable and has a bendability that permits plastic deformation by hand or with hand tools. The frame struc- ture 2 is adapted here to correspond in shape and dimensions to the Margo Supraorbitalis. The implant has two attachment tabs 8, both of which are integrally connected to the frame structure 2. The attachment tabs are dimensioned and located so that they can be attached to the nasal bone. In particular, the screw holes 10a, which can be used for screwing to the nasal bone, serve this purpose. The frame structure also includes screw holes 10 which serve the same purpose. Here, the frame structure 2 is continuous between the two attachment tabs 8. Therefore, the in- termediate area 9 between the attachment tabs is part of the frame structure 2. This is particularly advantageous if the treatment requires support and stabilization in this area and / or the shape and dimensions of the implant are so precisely adapted to the anatomy that further adaptation is unnecessary. Irrespec- tive of this, however, the adaptation area 3 can of course be plastically deformed and / or cut to accommodate a particular anatomy. Fig. 3 shows an alternative embodiment of an implant 1 according to the invention, which has two frame structures 2 that partial- ly form the outer edge 4 of the implant. As a result, the im- plant comprises two further areas 5a, 5b of the outer edge 4 which are not bounded by frame structures. The sheetlike adapta- tion area 3 is also designed here so that it can be plastically deformed and cut to size. In particular, it is dimensioned and designed, for example by material selection and / or shape, such that plastic deformation and / or cutting can be performed by hand or with hand tools. Suitable hand tools include, in particular, commercially available pliers and cutting instruments. The im- plant has an approximately square shape with rounded corner re- gions with a radius, where the frame structures are also ar- ranged. As a result, the present implant comprises a region lla which has no sharp points or fraying, in particular due to the frame structure. A second region 1llb, which in the present exam- ple is opposite region lla, is particularly suitable for being cut to a smaller size by an operator because of the lack of frame structures. Preferably, the cutting is performed on the side facing away from the frame structures. However, it is of course also possible to cut the adaptation area to any shape, in particular also between the two frame structures. This results in a smaller implant with only one frame structure. The flexi- bility of the cutting makes this implant particularly suitable for use where precise adaptation of the implant prior to surgery is not possible or is difficult and flexibility in use is there- fore important. For example, this is the case in the treatment of bones, which typically have a large variation in size and shape between individuals.. Alternatively, it would of course be conceivable to also cut the implant within the frame structure. The frame structure there- fore does not have to be designed in such a way that it cannot be cut to size. In general, however, it is advantageous to ar- range the frame structure in such a way that it does not have to be cut to size in the most common applications. In this way, the frame structure forms an area without sharp edges. Fig. 4 shows a detailed representation of the sheetlike adapta- tion area 3 and the geometry of the lattice. The present grid comprises holes 6 and connection areas 7 designed as ribs. The connection areas connect circumferential areas of the holes 6. In the embodiment shown here, each circumferential area of a hole 6 is connected to four connection areas 7. These are evenly distributed along the circumference of the holes, i.e. approxi- mately at 90° intervals. The connection areas are further dimen- sioned so that they can be cut through with hand tools. Here, the holes have an outer diameter of 3.1 mm. However, it would also be conceivable to form holes with a different outer diame- ter, in particular an outer diameter in the range from 2 to 5 mm, preferably in a range from 3.0 to 3.22 mm. The wire-like el- ements forming the ribs as well as the circumferential areas of the holes have a width of 0.6 mm, but could alternatively have a different width in the range 0.1 to 3.0 mm, preferably 0.5 to 0.7 mm. The grid area is approximately 0.5 mm thick, but could also have a different thickness in the range of 0.1 to 2.0 mm, preferably 0.3 to 0.6 mm. Particularly advantageous is the de- sign of the grid from a metal or a (resorbable) plastic. Accord- ingly, the variant shown here is made of titanium or a titanium alloy. This design allows the sheetlike adaptation area to be cut to a desired size. However, other dimensions and / or materi- als can of course be used. The geometry of the grid forming the sheetlike adaptation area 3 shown here is particularly advanta- geous for use in an implant due to the properties described here. However, it is of course also possible to use any other known lattice structure. Fig. 5 shows an alternative embodiment of an implant according to the invention. This corresponds essentially to the embodiment shown in Fig. 3, but further comprises two attachment tabs 8. These are similar to the attachment tabs used, for example, in the embodiment shown in Fig. 1. However, in the embodiment shown here, the attachment tabs 8 are not connected to a frame struc- ture. Instead, both attachment tabs 8 are directly connected to the edge region 5b of the implant 1 and are therefore located in a region with greater bendability of the implant. This allows the implant 1 to be used particularly advantageously in compli- cated anatomies because the attachment tabs 8 can be fixed with maximum flexibility. For this purpose, the attachment tabs 8 al- so have screw holes 10. It would of course be possible to com- bine the arrangement of the attachment tabs 8 shown in Figures 1 and 5. Thus, the variant shown here could also additionally or alternatively comprise further attachment tabs 8 in the area of the frame structures. Likewise, the embodiment shown in Fig. could be provided with further attachment are nc con- nected to the frame structure.

Claims

The claims defining the invention are as follows :

1. An implant for treatment of bone, in particular for covering 5        defects or drill holes or for a reconstruction of bone defects or malformations, comprising - at least one frame structure with a substantially uniform thickness, and - at least one adaptation area, in particular a sheetlike10        adaptation area,wherein the at least one frame structure is arranged outside the adaptation area and partially forms a first edge of the implant, wherein the first edge formed by the at least one frame15        structure does not continuously delimit the implant, sothat at least a second edge is not formed by the frame structure, wherein the frame structure is less bendable compared to the adaptation area, and wherein the at least one frame structure has an arc shape with a radius of cur-20        vature of 1 cm to 20 cm, the arc shape being concave andbent inwardly toward the at least one adaptation area, so that a center of curvature of the arc shape and the at least one adaptation area are located on opposite sides of the at least one frame structure, such that the at least25        one frame structure is dimensioned and positioned to be attached to the margo supraorbitalis.

2. An implant according to claim 1, wherein the implant comprises at least two frame structures, wherein both frame30        structures are each arranged outside the adaptation areaand partially form the edge of the implant, and the at least two frame structures do not continuously delimit the2020402123   25 Jun 2026outer edge, so that at least two areas of the outer edge are not delimited by the frame structure.

3. An implant according to one of claims 1 or 2, wherein the5        adaptation area is continuous and is free of frame struc-tures on the inside.

4. An implant according to any one of claims 1 to 3, wherein the frame structures are dimensioned and arranged such that10        at least half of the outer edge is continuously not delimited by the frame structures.

5. An implant according to any one of claims 1 to 4, wherein the adaptation area comprises a lattice structure dimen-15        sioned, in particular having a bendability, such that itcan be deformed by hand or with hand tools.

6. An implant according to any one of claims 1 to 5, wherein the implant comprises a biocompatible material, preferably20        a biocompatible material selected from the group consistingof implant steel, metals, ceramics, plastics, composites, particularly preferably titanium or a titanium alloy.

7. An implant according to any one of claims 1 to 6, wherein25        the adaptation area comprises connection areas dimensionedto be cut by means of hand tools.

8. An implant according to any one of claims 1 to 7, wherein the implant has at least one side length in a range of 1030        200 mm.

9. An implant according to claim 1, wherein the implant has at least two frame structure adapted to the margo supraor-2020402123   25 Jun 2026bitalis, and further having an intermediate region (5a) whose bendability is greater than that of the frame structures between the two frame structures adapted to the margo supraorbitalis, an intermediate region whose bendability is5        greater than that of the frame structures.

10. An implant according to any one of claims 1 to 9, wherein the implant comprises at least one attachment tab, preferably at least two attachment tabs.1011. An implant according to claim 10, wherein the at least one attachment tab is integrally connected to a frame structure, preferably to one of the at least two frame structures each.1512. An implant according to one of claims 10 or 11, wherein the at least one attachment tab is adapted for attachment to the nasal bone by the dimension, shape and positioning on the implant of the at least one attachment tab.2013. An implant according to any one of claims 1 to 12, wherein the implant is adapted to cover defects or drill holes or to reconstruct bone defects or malformations at a sinus.25   14. An implant according to any one of claims 1 to 12, whereinthe adaptation area is formed in integrally.

15. An implant according to one of claims 1 to 14, wherein the entire implant is formed integrally.3016. An implant according to any one of claims 1 to 15, wherein the adaptation area is plastically deformable.

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