Abstract
A bioabsorbable osteosynthesis implant, having a polymeric main body and at least one macroscopic reinforcement structure, which is integrated in the main body and is made of a biodegradable metal or a metal alloy.
Claims
1. A bioabsorbable osteosynthesis implant, having a polymeric main body and macroscopic reinforcement structures, integrated in the main body and made of a biodegradable metal or a biodegradable metal alloy, wherein at least one of the reinforcement structures runs parallel to a longitudinal axis of the implant and at least another of the reinforcement structures runs inclined along the longitudinal axis.
2. The osteosynthesis implant of claim 1, formed as a bone screw having a diameter between 1 mm and 15 mm, wherein the longitudinal axis is parallel to a screw axis and the incline is wound around the screw axis.
3. The osteosynthesis implant of claim 1, wherein the reinforcement structure is formed from magnesium or a magnesium alloy.
4. The osteosynthesis implant of claim 1, wherein the polymeric main body comprises a biopolymer.
5. The osteosynthesis implant of claim 4, wherein the biopolymer is selected from the group consisting of a poly-L-lactate, polyglycolic acid, and copolymer thereof.
6. The osteosynthesis implant of claim 1, wherein the polymeric main body comprises a polymer component in a range between 50% and 99% of a total mass of the main body.
7. The osteosynthesis implant of claim 1, which has a non-bioabsorbable component.
8. A bioabsorbable osteosynthesis implant having a polymeric main body comprising a polymer component that is 50% to 99% of a total mass of the body and at least one macroscopic reinforcement structure, which is integrated in the main body and is made of a biodegradable metal or a biodegradable metal alloy, wherein the polymeric main body comprises a non-bioabsorbable component formed as an end portion or a structural element of an end portion of a bone screw.
9. The osteosynthesis implant of claim 8, wherein the at least one macroscopic reinforcement structure is oriented along an incline from a longitudinal axis.
10. The osteosynthesis implant of claim 8, wherein the at least one macroscopic reinforcement structure is helically oriented around a longitudinal axis.
11. A bone screw comprising a polymeric main body and a macroscopic reinforcement structure comprising a biodegradable metal or biodegradable metal alloy integrated in the main body, wherein the reinforcement structure partially protrudes in a helical orientation from the main body to form an outer thread.
12. The bone screw of claim 11, further comprising another macroscopic reinforcement structure embedded in the main body and aligned parallel to a longitudinal axis of the screw.
Description
DESCRIPTION OF THE DRAWINGS
(1) Advantages and expedient features of the invention will also emerge from the following description of exemplary embodiments on the basis of the figures, in which:
(2) FIG. 1 shows a schematic side view of an embodiment of the invention in a use situation,
(3) FIG. 2 shows a perspective illustration of a further exemplary embodiment,
(4) FIG. 3 shows a perspective illustration of a further exemplary embodiment,
(5) FIG. 4 shows a perspective illustration of a further exemplary embodiment,
(6) FIG. 5 shows a perspective illustration of a further exemplary embodiment,
(7) FIG. 6 shows a perspective illustration of a bone screw in one embodiment of the invention, and
(8) FIG. 7 shows a perspective illustration of a medullary nail in accordance with one embodiment of the invention.
DETAILED DESCRIPTION
(9) FIG. 1 schematically shows a fractured bone B with fracture gap F, to which a plate-like osteosynthesis implant 10 is secured by means of a number of bone screws S, the implant having a reinforcement structure 11 at a middle part, which is formed as a solid magnesium body and is positioned over the fracture gap F, and two end portions 13a, 13b formed from a biopolymer. The magnesium reinforcement structure 11 at the middle part can be degraded more quickly in the body than the end portions 13a, 13b consisting of the biopolymer, whereby an expediently controlled load transfer to the healing bone B during the course of healing of the fracture is made possible. The end portions 13a, 13b may also consist of a non-bioabsorbable material, for example a titanium alloy.
(10) FIG. 2 shows a perspective view of an osteosynthesis plate 20 having reinforcement structures embodied as reinforcement struts 21 (for example made of Mg or an Mg alloy) running parallel to the longitudinal edges, embedded in a polymeric main body 23 (for example made of poly-L-lactate). A number of cylindrical through-holes 25 for passing through bone screws are provided in the main body 23. In a group of a number of struts the reinforcement struts 21 are each integrated continuously from one end to the other end of the osteosynthesis plate 20. They are used to increase the flexural rigidity of the implant over the entire length thereof.
(11) FIG. 3 shows, as a modification of the previously mentioned embodiment, a further osteosynthesis plate 30, which besides continuous groups of reinforcement structures embodied as reinforcement struts 31, which run parallel to the longitudinal edges of the plate, also has an additional central reinforcement structure 32 in a main body 33, which additional reinforcement structure is likewise formed from the material of the reinforcement struts 31. Here, this additional reinforcement structure again may be a group of individual struts, but may also be a comb-like solid reinforcement part. This structure 32 increases additionally the flexural rigidity of the plate 30 in the middle region thereof.
(12) FIG. 4 shows, as a further modification of the osteosynthesis plate from FIG. 2, a further osteosynthesis plate 40 having two groups of reinforcement structures embodied as reinforcement struts 41 running along the longitudinal edges. Here, an additional increase of the flexural rigidity in the middle region is provided by a first and second group 42A, 42B of reinforcement webs running at an incline to the longitudinal axes and crossing each other. The reinforcement strut groups 42A, 42B are arranged at different height level embedded in the polymeric main body 43. Also shown are number of cylindrical through-holes 45 for passing bone screws.
(13) FIG. 5 shows, as a modification of the aforementioned embodiment, an osteosynthesis plate 50, in which a plurality of first and second groups 52A, 52B of reinforcement structures embodied as reinforcement struts 51 each running at an incline to the longitudinal edges and crossing each other in the middle region of the polymeric main body 53 are arranged. An additional increase of the flexural rigidity is achieved in accordance with the plurality of additional reinforcement groups, moreover not only in the middle region of the implant, but practically over the entire length thereof. Also shown are number of cylindrical through-holes 55 for passing bone screws.
(14) FIG. 6 shows a bone screw 60 having a polymeric screw body 63, in the outer periphery of which a reinforcement structure embodied as a reinforcement helix 61 made of a biodegradable metal alloy is added as screw thread. This reinforcement helix 61 is thus incorporated in part into the main body 63 and protrudes partially therefrom.
(15) FIG. 7 shows, as a further exemplary embodiment of the invention, a medullary nail 70, in which an individual reinforcement strut 71 (shown in a dashed manner in the figure) is embedded centrally in a polymeric main body 73.
(16) In addition, the invention can also be embodied in a large number of modifications of the examples presented here and aspects of the invention highlighted further above.
(17) It will be apparent to those skilled in the art that numerous modifications and variations of the described examples and embodiments are possible in light of the above teaching. The disclosed examples and embodiments are presented for purposes of illustration only. Other alternate embodiments may include some or all of the features disclosed herein. Therefore, is it is the intent to cover all such modifications and alternate embodiments as may come within the true scope of this invention.
