Abstract
An implant system for treating fractures of a curved bone structure is proposed which comprises the following: an implant body which is provided to be arranged on the bone structure and to be in contact with the latter at least in some regions, wherein the implant body has a rod-like longitudinal extent, wherein the implant body has at least one middle piece which, at both ends, has at least one respective holding piece, wherein the holding pieces are each designed to be flexurally and/or torsionally resistant in such a way as to allow the respective holding piece to rest substantially flat along a particular region of the bone structure assigned to it, and wherein the at least one middle piece is designed to be elastic in such a way that the at least two holding pieces are bendable relative to each other about at least one flexion or torsion axis.
Claims
1. An implant system for treating fractures of a curved bone structure, comprising: an implant body configured to be arranged on the bone structure and to be in contact with the bone structure at least in some regions, wherein the implant body has a rod-like longitudinal extent, wherein the implant body has a middle piece which, at both ends, has a respective holding piece, wherein each holding piece pieces is designed to be flexurally and/or torsionally resistant in such a way as to allow the respective holding piece to rest substantially flat along a particular region of the bone structure assigned to it, and wherein the middle piece is designed to be elastic in such a way that the at least two holding pieces are bendable relative to each other about a flexion axis and a torsion axis, with the result that the middle piece is able to wrap around the bone structure at least in some regions.
2. The implant system as claimed in claim 1, wherein the implant body, with its rod-like longitudinal extent, has at least one region whose side edges have an undulating configuration on at least two mutually opposite sides.
3. The implant system as claimed in claim 1, wherein the middle piece and the two holding pieces have substantially the same outer contour.
4. The implant system as claimed in claim 1, wherein the thickness and/or length of the holding pieces and/or of the middle piece differ.
5. The implant system as claimed in claim 1, wherein the holding pieces have an increased thickness in relation to the at least one middle piece.
6. The implant system as claimed in claim 1, wherein a transition region is provided between at least one of the holding pieces and the middle piece.
7. The implant system as claimed in claim 6, wherein the transition region has at least one portion at an angle with respect to the longitudinal extent.
8. The implant system as claimed in claim 1, wherein at least one fastening means is arranged on the implant body.
9. The implant system as claimed in claim 8, wherein the fastening means is formed with one or more spikes, points, hooks or projections which are configured to penetrate into an osseous structure of the bone structure or to hold in place tissue that surrounds the implant body.
10. The implant system as claimed in claim 1, wherein the implant body is made from at least one high-performance polymer or composite thereof.
11. The implant system as claimed in claim 10, wherein the at least one high-performance polymer is a thermoplastic.
12. The implant system as claimed in claim 1, wherein the middle piece and the holding pieces have, on their face in each case directed toward the rib bone, a surface that is adapted to the associated bone region.
13. A method for production of an implant system for treating fractures of a curved bone structure, comprising at least the following production steps: making available an implant body mold which is divided into at least three different regions, in particular a middle region, and an end region located at each of the ends of the middle region; injecting at least one high-performance polymer into each of the regions of the implant body mold; cooling and/or crosslinking the high-performance polymers in the different regions in order to connect the regions to give the rod-shaped, flexible implant body with the elastic middle piece and the two holding pieces which are bendable relative to each other about the one flexion axis and the one torsion axis; removing the implant body from the implant body mold.
14. A method for production of an implant system as claimed in claim 1, wherein the flexible implant body with the elastic middle piece and with the two holding pieces, which are bendable relative to each other about the one flexion axis and the torsion axis, is produced in an additive method.
15. The implant system of claim 11, wherein the thermoplastic is selected from the group including a polyether ether ketone (PEEK) material, a polyether ketone ketone (PEKK) material, a polyphenyl sulfone (PPSU) material and a polyethylene (PE) material.
16. The implant system as claimed in claim 10, wherein the at least one high-performance polymer is a compound of a thermoplastic with one or more of hydroxyapatite, tricalcium phosphate, strontium, magnesium.
17. The implant system of claim 16, wherein the thermoplastic is selected from the group including a polyether ether ketone (PEEK) material, a polyether ketone ketone (PEKK) material, a polyphenyl sulfone (PPSU) material and a polyethylene (PE) material.
Description
DESCRIPTION OF THE DRAWINGS The invention is explained in more detail below on the basis of exemplary embodiments shown schematically in the figures of the drawing, in which:
[0027] FIG. 1a shows a perspective side view of a first embodiment of the implant system according to the invention with an implant body in extended form;
[0028] FIG. 1b shows a perspective side view of the implant body from FIG. 1a in a form in which it is bent about a flexion axis;
[0029] FIG. 1c shows a perspective side view of the implant body from FIG. 1a when arranged on the bone structure of a costal arch;
[0030] FIG. 1d shows a perspective side view of the implant body from FIG. 1c when seen from below;
[0031] FIG. 2a shows a perspective side view of a second embodiment of the implant system according to the invention with an implant body in extended form, in which, on the flat face directed away from the bone structure, the holding pieces are provided with points, but the middle piece has no points;
[0032] FIG. 2b shows a perspective side view of a detail region of the one holding piece of the implant body from FIG. 2a;
[0033] FIG. 2c shows a perspective side view of the implant body from FIGS. 2a and 2b, in which, on the flat face of the implant body directed away from the bone structure, both the holding pieces and the middle piece are provided with points;
[0034] FIG. 3a shows a perspective side view of a third embodiment of the implant system according to the invention with an implant body in extended form, in which, on the flat face directed away from the bone structure, the middle piece is provided with points;
[0035] FIG. 3b shows a perspective side view of a detail region of the middle piece of the implant body from FIG. 3a;
[0036] FIG. 3c shows a perspective side view of the implant body from FIGS. 3a and 3b, in which, on the flat face of the implant body directed toward the bone structure, only the middle piece is provided with points, and the faces of the middle piece and of the holding pieces lie in one plane;
[0037] FIG. 3d shows a perspective side view of a detail region of the middle piece of the implant body from FIGS. 3a-3c;
[0038] FIG. 4 shows a perspective side view of a fourth embodiment of the implant system according to the invention with an implant body in extended form, in which the holding pieces are configured with an undulating shape at their side edges, whereas the middle piece extends with parallel straight side edges; and
[0039] FIG. 5 shows a perspective side view of a fifth embodiment of the implant system according to the invention with an implant body in extended form, in which the holding pieces, at their side edges, are configured substantially with straight parallel side edges, whereas the middle piece extends straight but with undulating side edges.
[0040] In all of the figures, identical or functionally identical elements and devices are provided with the same reference signs, unless indicated otherwise.
DETAILED DESCRIPTION
[0041] FIGS. 1 to 5 of the drawings show an implant system 100 for treating fractures of a curved bone structure 50, which system comprises the following: an implant body 10, which is provided to be arranged on the bone structure 50 and to be in contact with the latter at least in some regions, wherein the implant body 10 has a rod-like longitudinal extent, wherein the implant body 10 has at least one middle piece 12 which, at both ends, has at least one holding piece 14, 16, wherein the holding pieces 14, 16 are each designed to be flexurally and/or torsionally resistant in such a way as to allow the respective holding piece 14, 16 to rest substantially flat along a particular region of the bone structure 50 assigned to it, and wherein the at least one middle piece 12 is designed to be elastic in such a way that the at least two holding pieces 14, 16 are bendable relative to each other about at least one flexion or torsion axis.
[0042] FIG. 1a shows a perspective side view of a first embodiment of the implant system 100 according to the invention with an implant body 10 in extended form. The implant body 10 is configured with a rod-like longitudinal extent and, both at the middle piece 12 and at the two holding pieces 14, 16 having the same outer contour, is provided with side edges which have a uniformly undulating shape at two mutually opposite sides. The undulating shape at the side edges results in the formation of an alternating series of projecting and recessed portions that merge into one another, wherein a recessed portion of one side edge is coincident with a projecting portion of the opposite side edge. In the projecting portions of the holding pieces 14, 16, receptacles 17 for the arrangement of fastening screws (not shown) are introduced perpendicularly with respect to the longitudinal extent. Arranged between the holding pieces 14, 16 and the middle piece 12 there is in each case a transition region 18, where a stepless transition is produced between the thicker holding pieces 14, 16, i.e. thicker perpendicular to the longitudinal extent, and the thinner middle piece 12. The transition pieces transfer the levels of the flat faces of the holding pieces 14, 16, which are flush with one another when the implant body 10 is not bent, into the level of the middle piece 12.
[0043] FIG. 1b shows a perspective side view of the implant body 10 from FIG. 1a in a shape in which it is bent about a flexion axis, wherein the flexion axis (not shown) in the plane defined by the middle piece 12 runs centrally and transversely to the longitudinal extent of the implant body 10.
[0044] FIG. 1c shows a perspective side view of the implant body 10 from FIG. 1a arranged on the damaged bone structure 50 of a costal arch. The damage to the bone structure 50, in the form of a fracture, can be clearly seen. The figure also shows one of the holding pieces 14, which is fastened to the bone structure 50, and also the middle piece 12 which is twisted about a torsion axis extending along the bone structure, in such a way that the implant body 10 wraps around the bone structure 50 through approximately 180°. FIG. 1d shows a perspective side view of the implant body from FIG. 1c in a view from below, in which both holding pieces 14, 16 and the middle piece 12 can be seen. FIGS. 1c and 1d also show that the holding pieces 14, 16 are spaced apart from the fracture itself, and the middle piece 12 wraps or engages around this region in such a way that, while promoting healing of the bone, it promotes a controlled movement and load distribution of the dynamic chest cavity.
[0045] FIG. 2a shows a perspective side view of a second embodiment of the implant system 100 according to the invention with an implant body 10′ in extended form, in which, on the flat face directed away from the bone structure 50 (not shown), the holding pieces 14′, 16′ are provided with points 22′ as fastening means 20′, whereas the middle piece 12 has no points 22′ on its flat face. In the implant body 10′, which again has a rod-like longitudinal extent, the middle piece 12′ and the holding pieces 14′, 16′ are once more provided with side edges that have a uniformly undulating shape at two mutually opposite sides. Here too, between the holding pieces 14′, 16′ and the middle piece 12′, there is in each case a transition region 18′, where a stepless transition is produced between the thicker holding pieces 14′, 16′ and the thinner middle piece 12′.
[0046] FIG. 2b shows a perspective side view of a detail region of the one holding piece 14′ of the implant body 10′ from FIG. 2a, showing that the points 22′ are arranged, in the direction of extent of the implant body 10′, in respective groups of three points 22′ along a line between the projecting and recessed portions. Here too, receptacles 17′ for the arrangement of fastening screws (not shown) are introduced into the projecting portions of the holding pieces 14′, 16′ perpendicularly with respect to the longitudinal extent.
[0047] FIG. 2c shows a perspective side view of the implant body 10′ from FIGS. 2a and 2b, in which, on the flat face of the implant body 10′ directed away from the bone structure, both the holding pieces 14′, 16′ and the middle piece 12′ are provided with points 22′, as a result of which the tissue surrounding the implant body 10′ is held in place.
[0048] FIG. 3a shows a perspective side view of a third embodiment of the implant system 100 according to the invention with an implant body 10″ in extended form, in which, on the flat face directed away from the bone structure, the middle piece 12″ is provided with points 22′. Once again, the implant body 10″ is configured with a rod-like longitudinal extent and, both on the middle piece 12″ and on the two holding pieces 14″, 16″ having the same outer contour, is provided with side edges which have a uniformly undulating shape at two mutually opposite sides. The undulating shape at the side edges results in the formation of an alternating series of projecting and recessed portions that merge into one another, wherein a recessed portion of one side edge is coincident with a projecting portion of the opposite side edge. In the projecting portions of the holding pieces 14″, 16″, receptacles 17″ for the arrangement of fastening screws (not shown) are introduced perpendicularly with respect to the longitudinal extent.
[0049] FIG. 3b shows a perspective side view of a detail region of the middle piece 12″ of the implant body 10″ from FIG. 3a. It shows that the points 22″ on the middle piece 12″ are in each case arranged individually on each projecting portion.
[0050] FIG. 3c shows a perspective side view of the implant body 10″ from FIGS. 3a and 3b, in which, also on the flat face of the implant body 10″ directed toward the bone structure, only the middle piece 12″ is provided with points 22′, and the faces of the middle piece 12″ and of the holding pieces 14″, 16″ lie in one plane.
[0051] FIG. 3d shows a perspective side view of a detail region of the middle piece 12″ of the implant body 10″ from FIGS. 3a-3c.
[0052] FIG. 4 shows a perspective side view of a fourth embodiment of the implant system 100 according to the invention with an implant body 10′″ in extended form, in which the holding pieces 14′″, 16′″ are configured with an undulating shape at their side edges, whereas the middle piece 12′″ extends with parallel straight side edges. Here too, a transition region 18′″ is arranged between each of the holding pieces 14′″, 16′″ and the middle piece 12′″. Regarding the undulating shape of the holding pieces 14′″, 16′″ and the receptacles 17′″ for fastening means, reference may be made to what has been said concerning FIGS. 1 to 3.
[0053] FIG. 5 shows a perspective side view of a fifth embodiment of the implant system 100 according to the invention with an implant body 10″″ in extended form, in which the holding pieces 14″, 16″″, at their side edges, are configured substantially with straight parallel side edges, whereas the middle piece 12′ extends straight but with undulating side edges. The receptacles 17′ for the arrangement of fastening screws have the same pattern here as in the case of an undulating configuration of the side edge and, at the ends of the holding pieces 14″, 16″″, their side edges converge at a receptacle 17″″.
[0054] The implant system 100 according to the invention solves the problem mentioned at the outset through the combination of an innovative and flexible design and the specifically chosen material properties, such as fatigue resistance, flexibility, ideal elastic modulus, material strength. It is thus possible to ensure a controlled load distribution and also controlled movement of the dynamic chest cavity, which, in contrast to a stiffer metallic system, promotes bone healing.
[0055] Although the present invention has been described above on the basis of preferred exemplary embodiments, it is not limited thereto and instead can be modified in a variety of ways. In particular, the present invention can be changed or modified in a variety of ways without departing from the core of the invention.
