Abstract
A bone implant (1) for stabilizing fractured or non-fractured bones comprises an implant body (2), preferably a cylindrical body, extending along a longitudinal axis (3) from a front side (4) to an end side (5). The implant has an implant width (6) extending perpendicularly to the longitudinal axis (3), and a length of the implant body (2) along the longitudinal axis (3) is at least 5 times the width (6) of the implant. The implant body (2) has an outer surface, being at least divided into a first surface (7) and a second surface (8. The first surface (7) comprises an anchorage area (9) which extends at least partially over the outer surface, preferably maximum over half of the outer surface.
Claims
1-15. (canceled)
16. A bone implant for stabilizing fractured or non-fractured bones, said implant comprising: an implant body extending along a longitudinal axis, from a front side to an end side, and having an implant width extending perpendicularly to the longitudinal axis, wherein a length of said implant body along id longitudinal axis is at least 5 times said implant width, said implant body has an outer surface which is divided at least into a first surface and a second surface, and said first surface consists of an anchorage area which extends at least partially over said outer surface.
17. The bone implant according to claim 16, wherein the implant comprises a bore extending along said longitudinal axis or parallel to said longitudinal axis having at least one opening at said front side and/or at said end side.
18. The bone implant according to claim 16, wherein the length of the bone implant is in a range from 10 mm to 250 mm.
19. The bone implant according to claim 16, wherein the width of the bone implant is in a range from 2 mm to 10 mm.
20. The bone implant according to claim 16, wherein said outer surface comprises holes having a wall around a hole axis.
21. The bone implant according to claim 20, wherein the implant (1) comprises a first set of holes, and said hole axis of said first set of holes is arranged substantially perpendicular to said longitudinal axis.
22. The bone implant according to claim 20, wherein the implant comprises a second set of holes, and said hole axis of said second set of holes is inclined relative to said longitudinal axis.
23. The bone implant according to claim 20, wherein said holes are distributed substantially equally in an area of 360° around said longitudinal axis of said outer surface or said second surface.
24. The bone implant according to claim 20, wherein said holes are located in an area from 180° to 270° around said longitudinal axis on said outer surface or said second surface.
25. The bone implant according to claim 16, wherein said anchorage area comprises means for improving fixation of the implant within bone.
26. The bone implant according to claim 16, wherein said anchorage area comprises surface structures in a form of grooves, distributed substantially equally around said longitudinal axis, extending coaxially along said longitudinal axis.
27. The bone implant according to claim 16, wherein the anchorage area comprises surface structures in a form of thread or ring shaped grooves.
28. A method of stabilizing a fractured or non-fractured bone by inserting a bone implant according to claim 16 into bone.
29. A bone implant for stabilizing fractured or non-fractured bones, said implant comprising: an implant body extending along a longitudinal axis, from a front side to an end side, and having an implant width extending perpendicularly to the longitudinal axis, wherein a length of said implant body along said longitudinal axis is at least 5 times said implant width, said implant body has an outer surface which is divided at least into a first surface and a second surface, and said first surface comprising an anchorage area which extends at least partially over said outer surface.
Description
[0061] In the following, the invention is described in embodiments by means of figures. It shows:
[0062] FIG. 1: a bone implant in a first embodiment,
[0063] FIG. 2: a first section of a bone implant in a second embodiment
[0064] FIG. 3: a cross-section through a bone implant in a third embodiment,
[0065] FIG. 4: a bone implant in a fourth embodiment,
[0066] FIG. 5: a cross-section through a bone implant according to FIG. 4,
[0067] FIG. 6: a bone implant in a fifth embodiment,
[0068] FIGS. 6a to 6c: a detailed view of FIG. 6,
[0069] FIG. 7: a cross-section through a bone implant in a sixth embodiment
[0070] FIG. 8: two bone implants stabilizing a fracture in a vertebra,
[0071] FIG. 9: two implants according to the third embodiment for stabilizing a fracture in a vertebra,
[0072] FIG. 10: a bone implant according to the first embodiment for stabilizing the humerus.
[0073] FIG. 1 shows a bone implant 1 according to a first embodiment. The bone implant 1 comprises an implant body 2 having a longitudinal axis 3. The implant body 2 comprises a front side 4 and an end side 5. Additionally, the implant body 2 is separated into a first surface 7 and a second surface 8. The first surface 7 comprises an anchorage area 9 for improving the anchorage of the implant in a bone. Perpendicular to the longitudinal axis, the implant body 2 comprises an implant width 6. The implant width 6 is constant along the first surface 7 and the second surface 8 and not exceeded at any other point of the implant 1. The second surface 8 comprises holes 12 and a bore 10 inside the implant body 2. The holes 12 enable the introduction of a fluid such as bone cement through the implant 1 into the bone and optimize the fixation of the implant 1 inside the bone due to growing bone tissue into the holes 12. The implant body 2 further comprises a third surface 17 which has a conical shape. The width of the implant is reduced in the third surface such that the introduction of the implant 1 into the bone is easier. The front side 4 of the implant body 2 is rounded such that it forms a semi-sphere to facilitate introduction of the implant 1 into the bone. The anchorage area 9 of the first surface 7 comprises a surface structure for improving the anchorage of the implant 1 inside the bone. The holes are distributed 360° around the circumference of the implant body 2, while the holes 12 are arranged in rows. The rows are offset relative to each other such that a first hole 12 of a first row 18 has a different distance from the front side 4 than a first hole 12 of a second neighbouring row (not shown). The length of an implant body is 100 mm while the implant width is 5 mm. The diameter of the holes 12 is 2.5 mm. The wall of the holes 12 has a cylindrical shape.
[0074] For example values for standard spinal implant will be: length from 50 to 85 mm, preferably mean 70 mm, diameter from 4 to 7 mm, preferably 5 mm, holes from 1 mm to 3 mm. preferably 2-2.5 mm.
[0075] FIG. 2 shows a cross-section through a second embodiment of the invention. In this embodiment, the implant body 2 comprises a bore 10 along the longitudinal axis. On the end side 5 a fixation connector is arranged to enable a connection of the implant body 2 with an insertion tool (not shown). Contrary to the first embodiment in FIG. 1, the holes 12 in the second embodiment are arranged over a larger second surface 8 relative to a smaller first surface 7. A first set of holes 12 comprises a hole axis 11a which is arranged perpendicular to the longitudinal axis 3. A second set of holes comprises an inclined axis 11b, while the inclination of the hole axis 11b is 120° relative to the longitudinal axis 3. The front side 4 further comprises a third surface 17 for facilitating introduction of the implant into a bone.
[0076] FIG. 3 shows a cross section of a third embodiment of the invention. In this embodiment the bore 10 comprises a fixation connector 16 on the end side 5 of the implant body 2 which is threaded. By means of this thread a tool can be fixed in the implant. The holes 12 are arranged 270° around the longitudinal axis 13 and hence a fluid such as bone cement is only directed 260° from the implant. This way, sensitive areas will not be filled with fluid or specific bone cement.
[0077] FIG. 4 shows a fourth embodiment of the invention. This embodiment corresponds to the first embodiment in FIG. 1 apart from the first surface 7 comprising the anchorage area 9. The anchorage area 9 comprises a thread in which the thread pitches extend from the implant width 6. Such an anchorage area 9 improves the fixation of the implant inside the bone. Furthermore, the third surface 17 in this embodiment is shorter relative to the embodiment in FIG. 1 and thereby a conical shape of the third surface 17 comprises a steeper inclination relative to the embodiment in FIG. 1. Additionally, the front side 4 is more peaked relative to the embodiment in FIG. 1.
[0078] FIG. 2 shows the embodiment as disclosed in FIG. 3 while the first surface 7 comprises an anchorage area 9 having a thread. The anchorage area 9 in this embodiment corresponds to the anchorage area 9 shown in FIG. 4.
[0079] FIG. 6 shows an embodiment of the implant 1 which comprises a first surface 7 having longitudinal grooves 13. The longitudinal 13 grooves improve the anchorage of the bone implant inside the bone. The longitudinal grooves can comprise a cross-sectional shape that is square, such that it avoids rotation (FIG. 6a), semi-spherical such that insertion is easier and the bone contact is better compared to square shapes or angles (FIG. 6b) or triangular such that the surface contact is maximised (FIG. 6c). The holes 12 in the embodiment according to FIG. 6 are only distributed from 270° up to 300° around the circumference of the implant 1.
[0080] FIG. 7 shows a cross-section through the embodiment according to FIG. 6. The bore 10 along the longitudinal axis 3 comprises a fixation connector 16 which enables a threaded connection to a tool (not shown). The holes 12 are arranged along three different hole axis 11a to 11c. The first hole axis 11a is arranged perpendicular to the longitudinal axis. The hole axis 11b for the second set of holes is arranged at 130° relative to the longitudinal axis 3. The hole axis 11c for the third set of holes is arranged at 60° relative to the longitudinal axis. Such a hole arrangement is especially suitable for an implant in a vertebra since bone cement introduced through the bore 10 and holes 12 is optimally distributed in the vertebra. The purpose is to avoid the risk of leakage through the vertebral body walls, anterior or posterior, that could have been damaged by a fracture.
[0081] FIGS. 8a to 8c show an exemplary embodiment of the use of the implant in a vertebra. FIG. 8a shows the top view, FIG. 8b shows a side view and FIG. 8c shows a rear view from a vertebra in which two implants are introduced for stabilizing the vertebra. The implants introduced in this embodiment are implants according to FIG. 1.
[0082] FIGS. 9a to 9c show the same views as FIG. 8 applying an embodiment of the implant according to FIG. 4.
[0083] FIG. 10 shows an implant 1 used as a stabilizing implant in a humerus. The humerus is not fractured. The implant 1 is nevertheless introduced into the bone for stabilizing it. The arrow shows the way of introducing implant 1 into the humerus.
