CONNECTOR FOR SPINAL COLUMN SUPPORT

Abstract

A connector for connecting two supporting rods of a spinal column supporting device, which rods are placed or are to be placed along a portion of spinal column. The connector includes a transverse rod, a first coupling that couples the transverse rod to a first one of the supporting rods and a second coupling that couples the transverse rod to the second one of the supporting rods. At least one of the couplings has a clamping region that clamps the supporting rod with a clamping force and a force application component for generating an axial force that produces the clamping force, in particular in the form of an axial tensioning screw, the axial force being caused by screwing in of the screw, and the axial force being directed through the transverse rod.

Claims

1-18. (canceled)

19. A connector for connecting two support rods of a spinal column support device, which support rods are placed or are to be placed along a spinal column portion, the connector comprising: a transverse rod; a first coupling that couples the transverse rod to a first of the support rods; and a second coupling that couples the transverse rod to a second of the support rods, wherein at least one of the couplings has a clamping region that clamps the support rod with a clamping force, and has force applicator for generating an axial force that brings about the clamping force, the force applicator being an axial clamping screw and the axial force being caused by screwing in said clamping screw, wherein the axial force is guided through the transverse rod.

20. The connector according to claim 19, wherein a first part of the clamping region has a resilient arm.

21. The connector according to claim 20, wherein the clamping region is configured to be clippable onto the support rod.

22. The connector according to claim 20, wherein the coupling has a material weakening that facilitates a resilient mount of the resilient.

23. The connector according to claim 20, wherein a rest for the transverse rod that is formed on a side of the transverse rod distant from the clamping screw is located axially at a higher level in a region of the resilient arm than in any other part of the clamping region when no axial force is applied.

24. The connector according to claim 22, wherein, as seen in an axial section, the material weakening has an asymmetric form in relation to the clamping screw.

25. The connector according to claim 19, having an adoptable first positioning state, in which the transverse rod is kept at a positioning distance from the support rods in the couplings by a preloaded state of the force applicator.

26. The connector according to claim 25, wherein the positioning state is adjustably variable.

27. The connector according to claim 25, having an adoptable securing state, in which the clamping force still allows movements of the coupling along the support rod but no longer allows said coupling to lift off from the support rod.

28. The connector according to claim 27, having an adoptable state of rigid coupling between the support and transverse rods, this state being brought about by a full application of the force applicator by tightening the clamping screw.

29. The connector according to claim 19, wherein both of the couplings have the clamping region and the force applicator.

30. The connector according to claim 29, wherein the first and second couplings are identical.

31. The connector according to claim 19, wherein the axial direction runs orthogonal to a direction of extent of the transverse rod, the axial direction runs orthogonal to a direction of extent of the first and/or second support rod, and/or the direction of extent of the transverse rod runs orthogonal to the first and/or second support rod.

32. An assortment comprising: a connector according to claim 19 and at least two transverse rods with different lengths and/or transverse dimensions.

33. An assortment, according to claim 32, comprising at least one, preferably at least two connectors, wherein at least two couplings that are assigned to one or two connectors have clamping regions designed to clamp support rods with different transverse dimensions.

34. The connector according to claim 19, wherein the connector is made of biocompatible material.

35. A coupling of a connector for connecting two support rods of a spinal column support device, which support rods are placed or are to be placed along a spinal column portion, the coupling is configured to guide an axial force through a transverse rod.

36. A spinal column support device, comprising: two support rods; and a connector according to claim 19 that connects said support rods.

Description

[0019] Further features, details and advantages of the invention arise from the following description with reference to the attached drawing, in which

[0020] FIG. 1 shows a part of a coupling of a connector, to be precise

[0021] FIG. 1a shows a front view with a direction of view in the connection direction,

[0022] FIG. 1b shows a side view with a direction of view along the extent of the support rod, and

[0023] FIG. 1c shows a sectional view orthogonal to the direction of view of FIG. 1b,

[0024] FIG. 2 shows a connector, to be precise without clamping screws in FIG. 2a and with clamping screws in FIG. 2b, and

[0025] FIG. 3 shows a sectional view of FIG. 2b, with force arrows being plotted.

[0026] FIG. 1 illustrates a receptacle 10, which together with a clamping screw, which is not illustrated in FIG. 1 and which interacts with the thread 12 of the receptacle 10 and together with a transverse rod 30, in a respective double implementation, forms a connector 100 which is illustrated in interacting fashion in FIG. 2b and which interconnects two support rods 40a, 40b by way of transverse stiffening.

[0027] Even though this is not illustrated in FIG. 2b, the support rods 40a, 40b are parts of a spinal column support device and when implanted into the human body are rigidly connected via suitable couplings to pedicle screws that are screwed into vertebrae. Such spinal column support devices are known from the art and therefore not discussed in more detail; instead, reference is made to relevant systems in this regard, as are disclosed for example in WO 2009/015100 A2 and EP 2 581 057 B1, the documents respectively being incorporated by reference.

[0028] It is evident from the front view of FIG. 1a that in the axial direction Z the receptacle 10 has a recess on its upper side, a receptacle space in the form of a continuous groove in the Y-direction being formed at the lower end region of said recess. As is likewise evident from FIG. 1a and FIG. 2a, the transverse rod 30 can be introduced into the receptacle space from the top, along the recess and in the axial direction, the receptacle space for the transverse rod being formed at the lower end region of said recess. The side regions that extend along the recess in the axial direction bear the thread 12 on their inner sides. With the direction of view in the axial direction Z, the recess appears as a threaded bore, which is perforated by the groove 13 in the transverse direction Y.

[0029] A receptacle groove 14 which extends transversely to the groove 13—orthogonally in this exemplary embodiment—and which is better identifiable in FIG. 1b is formed in the lower region of the receptacle 10 in relation to the axial direction Z. This receptacle groove is designed to receive a support rod 40 (not illustrated in FIG. 1) and surround the latter over more than 180° in the circumferential direction. A resilient arm 16, which is arranged centrally in relation to the direction of extent of the direction of extent X of the support rod 40, together with a side holder 17 opposite said resilient arm forms a clamping region, in which the support rod 40 is clamped and ultimately securely fixed.

[0030] To this end, the constriction between the facing lower end portions of the side holder 17 and of the resilient arm 16 has an intervening space that is smaller, but only just smaller, than the diameter of the support rod 40 in a preferred embodiment. The clamping region 16, 17 can consequently be clipped onto the support rod 40, with the resilient arm 16 elastically deforming during the clip-on movement on account of its resilient mount. The resilient mount in the transition region to the side holder 17 is facilitated by a material weakening 76 in the form of a bore that traverses the receptacle 10 in the X-direction. Consequently, a material bridge remains between the lower edge of the bore 76 in FIG. 1c and the section of the boundary of the groove 14 lying opposite thereto.

[0031] Once the receptacle 10 has been clipped onto the rod 40, it can conversely also be removed from rod 40 again, unless the clamping force of the clamping region 16, 17 is so strong as a result of the effect of the force application means, formed by the clamping screw 20 in this exemplary embodiment, that lifting off in the radial direction is no longer possible.

[0032] It is clearly evident from FIG. 1c and its enlarged detail that the level Z16 of the upper face 16a of the resilient arm 16, which face forms a bearing face for the transverse rod 30, is higher than the level Z17 of the upper face of the side holder 17, which face likewise is a bearing face for the transverse rod 30, by height difference AZ in the axial direction Z in a state when no force is applied. Consequently, if the resilient arm 16 denotes the movable limb and the side holder 17 denotes the fixed limb of the clamping mechanism, realized here, under the application of axial force, the bearing face 16a of the movable limb is closer to the thread 12 than the bearing face of the fixed limb 17 in the axial direction Z.

[0033] If the clamping screw 30 is now screwed into the thread 12, the axial force caused thereby is guided through the transverse rod 30 and initially acts on the bearing face of the resilient arm 16, which is pressed axially downward as a result, and this is reflected in radial transverse forces, plotted in the Y-direction in FIG. 3, on account of the inner faces of the clamping region being complementary to the rod 40. In this case, the inner faces of the clamping region 16, 17 establish pressurized contact around the rod 40 over an angle region greater than 180°, preferably greater than 200°, and approximately 225° in the present embodiment.

[0034] It is understood that tightening of the clamping screw 20a (that is to say, exerting a torque that is above a specified critical threshold) ensures fixed rigid coupling of the support rod 40 with the receptacle 10. It is furthermore understood that, on account of the structural design of guiding the axial force through the transverse rod, the transverse rod 30 is also rigidly and securely coupled to the receptacle 10 in the process (this state is shown in FIGS. 2b and 3).

[0035] During use, the two receptacles 10a, 10b (FIG. 2a) of the connector 100 for example could be separately clipped onto the support rods 40a, 40b to be connected and as shown in FIG. 2a the transverse rod 30 could be introduced into the receptacles 10a, 10b until it comes to rest on the bearing faces 16a of the respective resilient arms 16 in the transverse rod channel 13. As an alternative to the design of FIG. 2, it would also be possible for the receptacles 10a, 10b, before these two receptacles are clipped on, to be coupled to one another by means of the transverse rod 30 and the clamping screws 20a by very slightly screwing in the clamping screws 20 so as to prevent slippage out of the channel 13 in the Z-direction so that the distance between the two couplings is only still adjustable by displacement along the Y-axis, and for this distance to be suitably adjusted in relation to the distance of the support rod 40a, 40b and be set by screwing the clamping screws 20a, 20b slightly further. In this state, the couplings that have already been connected to the transverse rod 30 can also be clipped together onto the respective support rods 40a, 40b.

[0036] Further screwing then prevents the couplings from being released from the support rods 40a, 40b but still permits a common displacement, undertaken along the direction of extent X thereof, for the appropriate setting of the final position, in which, at the right mutual distance and at the right level in respect of the extent of the spinal column, the connector is finally set to rigid coupling by tightening the clamping screws 20a, 20b.

[0037] As is evident from the aforementioned options, it is easy to manage the connection of the support rods 40a, 40b and the connector makes do with a few components.

[0038] It is likewise evident to a person skilled in the art that the structure of the receptacle 10 of the coupling is not restricted to that of the embodiment illustrated in exemplary fashion.

[0039] Rather, the individual features of the description above and of the claims below may be essential, either on their own or in any combination, for the implementation of the invention in its various embodiments.