SPINAL COLUMN IMPLANT CONNECTION DEVICE

Abstract

A connection device for connecting an end region of an already implanted first spinal column support, at which pedicle screws are coupled on their head side to a first connection rod by respective coupling devices, to an already or not yet implanted spinal column support portion having a pedicle screw and extending the first spinal column support, having a first fastening arrangement for fastening the connection device to the first connection rod and a coupling for the extending support portion, in particular a second rod to be coupled to the pedicle screw of the extending support portion or a second fastening arrangement for fastening the connection device to such a second rod, further having a rigid bridge, laterally clinging to the coupling device of the closest pedicle screw of the first spinal column support on the connection side, of an intermediate region between the first fastening arrangement and the coupling.

Claims

1-15. (canceled)

16. A connecting device for connecting an end region of an already implanted first spinal column support, in which a plurality of pedicle screws are respectively coupled at a head side to a first connecting rod by a respective coupling device in each case, comprising an already implanted or yet to be implanted spinal column support section which has a pedicle screw and which lengthens the first spinal column support, the connecting device comprising: a first fastening arrangement for fastening the connecting device to the first connecting rod; a coupling for the lengthening support section; and a rigid bridge of an intermediate region between the first fastening arrangement and the coupling, said bridge laterally nestling against the coupling device of a closest of the pedicle screws of the already implanted first spinal column support on the connection side.

17. The connecting device according to claim 16, wherein the coupling for the lengthening support section is a second rod coupleable to the pedicle screw of the lengthening support section or is a second fastening arrangement for fastening the connecting device to such a second rod.

18. The connecting device according to claim 16, wherein the nestling is lateral nestling on both sides.

19. The connecting device according to claim 17, wherein the bridge has a vertical extent that does not exceed a height of the coupling device by more than 100% of a vertical dimension of the coupling device.

20. The connecting device according to claim 19, wherein the vertical extent of the bridge that does not exceed the height of the coupling device by more than 60% of the vertical dimension of the coupling device.

21. The connecting device according to claim 20, wherein the vertical extent of the bridge that does not exceed the height of the coupling device by more than 30% of the vertical dimension of the coupling device.

22. The connecting device according to claim 17, further comprising a third fastening arrangement for fastening said connecting device to the first connecting rod at a free end thereof on the connection side.

23. The connecting device according to claim 22, wherein, for purposes of positioning the connecting device in relation to the first spinal column support, the first fastening arrangement is configured to be placeable radially and from above on an end region comprising the coupling device of the closest pedicle screw on the connection side.

24. The connecting device according to claim 23, wherein the first and/or the third fastening arrangement includes a resilient device that clips the first and/or the third fastening arrangement on the end region.

25. The connecting device according to claim 22, further comprising clamping means for clamping the first connecting rod to the first and/or the third fastening arrangement.

26. The connecting device according to claim 25, wherein the clamping means includes a clamping screw arranged off-centered in relation to a receiving region of the first and/or the third fastening arrangement that receives the first connecting rod.

27. The connecting device according to claim 17, wherein the second fastening arrangement includes a block of material having an axial bore configured for axial insertion of the second rod in a longitudinal direction of the second rod.

28. The connecting device according to claim 17, configured for substantially collinear relative positioning of the first connecting rod and the second rod.

29. The connecting device according to claim 25, having an axial dimension and a maximum transverse dimension that is less than ⅓, preferably less than 2/7 of the axial dimension, and/or less than 440%, in particular 360% of a diameter of the receiving region for the first connecting rod.

30. The connecting device according to claim 29, wherein the maximum transverse dimension is less than 2/7 of the axial dimension.

31. The connecting device according to claim 29, wherein the maximum transverse dimension is less than 360% of the diameter of the receiving region for the first connecting rod.

32. An extension set for lengthening an already implanted first spinal column support, comprising: a connecting device according to claim 16; at least one pedicle screw; a second rod, optionally already as part of the connecting device; and at least one coupling device for forming a rigid connection between the pedicle screw and the second rod.

33. The extension set according to claim 32, made of a biocompatible material.

34. A spinal column support, comprising: a first spinal column support with a plurality of pedicle screws, which are each coupled at a head side to a first connecting rod by a respective coupling device; and an extension connected by a connecting device according to claim 16.

35. An assortment, comprising: at least two connecting devices according to claim 16, wherein the first fastening arrangements of the two connecting devices are embodied differently from one another in order to be fastened to connecting rods with different transverse dimensions so as to be placeable on coupling devices of different sizes, and/or the at least two connecting devices have second rods of different lengths.

Description

[0022] Further features, details and advantages of the invention will become apparent from the following description relating to the attached figures, in which

[0023] FIG. 1a is a perspective view of a connecting device of a first embodiment,

[0024] FIG. 1b is a plan view of the connecting device of FIG. 1a,

[0025] FIG. 2a comprises a sectional view taken along the line A-A from FIG. 1a,

[0026] FIG. 2b comprises a sectional view taken along the line B-B in FIG. 1b,

[0027] FIG. 3a shows a top view of the connecting device from FIG. 1a in its connecting use,

[0028] FIG. 3b comprises a sectional view along the line A-A from FIG. 3a,

[0029] FIG. 3c comprises a sectional view along the line B-B in FIG. 3a,

[0030] FIG. 4 shows a second embodiment of a connecting device,

[0031] FIGS. 5a, 5b, 5c correspond to FIGS. 3a, 3b and 3c for this second embodiment, and

[0032] FIG. 6 shows a connecting device known from the prior art.

[0033] A connecting device 10 of a first embodiment is illustrated in a perspective view in FIG. 1a. A first fastening arrangement 1 with a spring arm 1a and a bore 11 provided with a thread, not shown, for screwing in a clamping screw, not shown, can be recognized far right in FIG. 1a. The first fastening arrangement 1 is used to fasten the connecting device 10 to a connecting rod 60 (FIG. 3a) of a spinal column support.

[0034] The connecting device 10 has a second fastening arrangement 2 in the left end region of FIG. 1a. This has a bore 22, which is embedded in the material of the end region and which extends in the longitudinal direction of the connecting device 10, and threaded through-bores 12 which run in the vertical direction and extend as far as the bore 22. In this way, a rod inserted into the bore 22 can be fixed by means of locking screws, not shown, which are screwed into the threaded bores 12. The second fastening arrangement 2 thus serves to fasten a rod 40 which forms part of a support which lengthens the spinal column support having the connecting rod 60, although only the rod 40 itself is shown in FIG. 3b. An intermediate region 5 between the first fastening arrangement 1 and the second fastening arrangement 2 has adjacent to the first fastening arrangement 1a sheath-like region 4, the interior 6 of which is cylindrical in this exemplary embodiment, the cylinder axis extending in the vertical direction. As can be seen from FIG. 1a, the sheath-like region 4 is connected in one piece to the first fastening arrangement 1. In the connection use, a coupling device 80 is received in the interior 6, the coupling device coupling a pedicle screw 70 of the spinal column support to its connecting rod 60 in a fixating manner. As can be seen from FIG. 1a, the first fastening arrangement 1 and the second fastening arrangement 2 are connected to one another in one piece via the intermediate region 5.

[0035] Between the sheath-like region 4 and the second fastening arrangement 2 there is also a third fastening arrangement 3 with a spring arm 3a and threaded bore 13, which in this exemplary embodiment is structurally identical to the first fastening arrangement 1 and is explained below with reference to FIG. 2. The third fastening arrangement 3, like the fastening arrangement 1, serves to fix the connecting device to the connecting rod 60 of an already implanted spinal column support, but on the side of the coupling device 80 facing away from the fastening arrangement 1, at the free end of the connecting rod 60. The first and third fastening arrangements 1, 3 thus in a sandwich-like manner surround the coupling device of the spinal column support to be lengthened, and the sheath-like region 4 or its lateral walls 48 nestle against the coupling device 80. As can be seen from FIG. 1a, the first fastening arrangement 1 and the third fastening arrangement 3 are connected to one another in one piece via the sheath-like region 4.

[0036] As can be seen in FIG. 2a, a receiving channel 16 for the connecting rod 60 runs axially centrally and almost coaxially to the bore 22 in this exemplary embodiment. In the region of the first and third fastening arrangement, the mouth opening of the channel 16 in the unloaded state of the spring arms 1a, 3a is slightly narrower than the diameter of the channel 16. Thus, with elastic yielding of their resilient arms 1a, 3a the fastening arrangements 1, 3 can be clipped onto the connecting rod 60, while the sheath-like region 4 is slipped over the coupling device 80 during this clipping-on movement.

[0037] The threaded bores 11 and 13 do not extend as far as the channel 16 (FIG. 2). Additionally, as can be seen in FIG. 1b and FIG. 2b, these are arranged off-centered in relation to the central axis of the connecting device 10 and displaced in the direction of the resilient arms 1a, 3a, and so when the clamping screws are screwed in, the resilient effect of the spring arms 1a, 3a is initially canceled and taking the connecting device 10 off the spinal column support (rod 60) again is blocked in this state. With further tightening or securing of the clamping screws, the connecting device 10 is rigidly and firmly connected to the connecting rod 60 of the already implanted spinal column support. The rod 40 of the lengthening section of this spinal column support is thus also rigidly and firmly connected via the second fastening arrangement 2 to the spinal column support to be lengthened. As can be seen from FIG. 2b, the thread for the bore 11 and the opposing lateral boundaries of the channel 16 are connected to one another in one piece.

[0038] In this exemplary embodiment, the function of clipping-on the fastening arrangement 1 is realized by virtue of, as viewed in cross section to the channel 16, the boundary thereof being formed on one side by the inner face of the resilient arm 1a, on the opposite side by a side structure of the fastening arrangement 1 adopting the function of the fixing arm 1b, and the two arms 1a and 1b being connected to one another only by a material bridge 1c of small thickness. The material and dimensions of the material bridge 1c are, however, matched to one another in such a way that the resilient arm 1a is prevented from breaking off in the event of accidental, unintentional application of force. As can be seen from FIG. 2b, the lateral boundaries 1a, 1b of the channel lie opposite one another with respect to a transverse direction or lateral direction, which runs orthogonally to the threaded bore 11. As already explained above, the threaded bore 11 is not arranged centrally with respect to the lateral boundaries 1a, 1b, but is displaced off-center in the transverse direction towards the spring arm 1a.

[0039] In addition to the illustrated sectional representations, constituent parts recognizable in projection are also imaged in the figure representations of FIG. 3, for instance the pedicle screw 70 in FIG. 3c or the side regions 48 of the sheath-like region 4, so as to be able to recognize the relative position of these parts/objects. It can be clearly seen from FIG. 3a in particular that the side of the connecting device 10 that is coupled to the connecting rod 60 wraps like a sleeve or bandage around the end region of the already implanted spinal column support that has not only the connecting rod 60 but also the coupling device 80. In this exemplary embodiment, the maximum transverse dimension of the connecting device 10, formed here by the transverse spacing between the two side walls 48 of the sheath-shaped region 4, thus is only about 2.5 times the diameter of the connecting rod 60 or the channel 16 designed to accommodate it.

[0040] The connecting device 10 can simply be clipped onto this end region without requiring a manipulation of the end region on the rod 60 and/or the coupling device 80, and without requiring loosening of the locking screw 82 of the coupling device 80. The latter can be designed according to the techniques used over the years, which are described for example in WO 2009/015100 A2 or EP 2 581 057 B1, with, for example, a tulip, a saddle received in the tulip in which the head of the pedicle screw 70 is received, and the screw 82 which exerts clamping pressure on the saddle via the connecting rod 60 for the fixed coupling of the screw 70, in particular designed as a polyaxial screw, in the desired angular position in relation to the connecting rod 60. Similar systems can then also be used for the lengthening spinal column support section with the rod 40.

[0041] When viewed in the vertical direction, as shown in FIG. 3b, the upper section of the coupling device 80 can be received entirely within the interior 6 of the sheath-like region 4. In this way, a comparatively flat surface side of the connecting device can be formed in the deployed state.

[0042] It is apparent to a person skilled in the art that various alternative structural designs are conceivable for this embodiment, for example the axes for the rods 40, 60 need not be collinear, not even parallel, if angled connections are required. The second fastening arrangement 2 could also be designed differently, for example similar to the first fastening arrangement or with a lateral insertion channel instead of the blind hole 22. The sleeve-like nestling could also be achieved by lateral clipping onto the connecting rod 60; for this purpose, the sheath-like region 4 would have to be modified to suit a lateral attachment. In the case of a correspondingly rigid configuration, one of the side arms 48 of the sheath-like region 4 can also suffice. The downwardly protruding flange-like end portions of the side walls 48 could, for example, be shorter or have incisions, or the structure of the sheath-like region can be replaced by a ring structure corresponding to its upper region. In the case of very short protruding free ends of the connecting rod 60, variants are also considered in which the third fastening arrangement is displaced to the side of the first fastening arrangement or the first fastening arrangement alone ensures sufficient coupling to the connecting rod 60.

[0043] Additionally, the rod of the lengthening section can already be a firmly coupled constituent part of the connecting device. Such an embodiment is shown in FIG. 4 in a schematic representation. What can be seen is that in the connecting device 10′ shown there, the rod 40′ acting to lengthen the rod 60 is already connected in one piece, for instance via a flange 2′ of the connecting device 10′ adjacent to the third fastening arrangement 3. As can be seen from FIG. 4, the flange 2′ and the first fastening arrangement 1 are connected to one another in one piece via the intermediate region 5. In this way, a plurality of connecting devices 10′ with rods 40′ of different lengths can also be provided, depending on the length dimension of the extension required. The rest of the design of the connecting device 10′ can correspond to that of the connecting device 10 from FIG. 1a, in this respect the same reference signs are also used to denote equivalent parts, and the representations in FIGS. 5a, 5b and 5c correspond, functionally and constructively in this exemplary embodiment, to the representation of figure group 3 of the first embodiment, precisely apart from the already provided rod 40′. It is understood that mixed forms can also be used, for example the connection between rod 40′ and flange 2′ could be formed not in one piece and a rod 40″ could be screwed into a flange 2″ instead.

[0044] In terms of material, the constituent parts of the connecting device are made of a biocompatible material, such as stainless steel, titanium or biocompatible polymers, as they are known as such to the person skilled in the art.

[0045] Preparing the connecting device for use can comprise a disinfection step and/or an autoclaving step, and also the appropriate provision of not only the connecting device, but also the entire lengthening spinal column support with a connecting rod 40 (40′, 40″) of appropriate length and pedicle screws/coupling devices similar to the pedicle screw 70 and coupling device 80 shown in FIGS. 3 and 5, for the specific designs of which conventional structures are available, such as those presented in the documents referred to above.

[0046] The invention is therefore not restricted to the embodiments described in the examples illustrated. Rather, the individual features of the above description and the following claims can be essential individually and/or in combination for the implementation of the invention in its various embodiments.