Spinal Braces Connectors

Abstract

The invention relates to a connector (100) for connecting two support rods (40a, 40b) of a spinal support device, which are placed or are to be placed along a spinal column portion, the connector comprising a transverse rod (30), a first connector (10a) connecting the transverse rod to the first support rod and a second connector (10b) connecting the transverse rod to the second support rod, at least one connector having a clamping area (16, 17) for clamping the support rod with a clamping force and having a force application device for generating an axial force causing the clamping force, the force application device being in particular in the form of an axial clamping screw, the axial force being caused by screwing in the clamping screw and the axial force being guided via the transverse rod.

Description

Technical Field

[0001] The present invention relates to a connector for connecting two support rods of a spinal support device, which are placed or to be placed along a spinal column portion, comprising a transverse rod, a first connector connecting the transverse rod to the first support rod, and a second connector connecting the transverse rod to the second support rod, wherein at least one connector has a clamping area for clamping the support rod with a clamping force, and has a force applying device for generating an axial force of the clamping force, the force applying device is specifically in the form of an axial clamping screw, and the axial force is caused by screwing in the clamping screw. Background Art

[0002] Such connectors are known, for example from US 2007 / 004932 A1. In the connector taught therein, screwing in the clamping screw not only generates a clamping force for clamping the support rod, but the clamping screw is also surrounded by an expansion sleeve which expands radially during screwing in, thus also clamping the transverse rod in the transverse rod groove. Summary of the invention

[0003] The invention is based on the object of developing a connector of the type described in the introduction, in particular with a view to achieving a satisfactory combination of a simple structure of the connector and a simple operation thereof.

[0004] The invention achieves this object by improving a connector of the type described above, the main feature of which is that the axial force is guided through the transverse rod. The transverse rod is therefore part of the force transmission path along which clamping is achieved by applying force or establishing a rigid coupling between the connecting rod and the transverse rod, for example from screwing in to tightening the clamping screw.

[0005] The present invention simplifies processing and the connector uses fewer components.

[0006] Further preferred embodiments and aspects of the invention are specified in the dependent claims.

[0007] Therefore, preferably, the first part of the clamping area has a resilient arm. In this case, the clamping area can be clamped on the support rod by deformation of the resilient arm and pressed back to its original position due to its resilient mounting. It is understood that the clamping can preferably be performed by hand without tools.

[0008] Preferably, the clamping region is in one-piece form and, in particular, is formed in one piece with the connection element except for the force-exerting means (e.g. the clamping screw). In this context, it is particularly preferably provided that the elastic mounting of the spring arm is facilitated by a material weakening of the connector. For example, the latter can be formed by a hole through the connector body. This simplifies production with as few components as possible.

[0009] In a particularly preferred embodiment, the abutment for the transverse rod formed on the side of the transverse rod facing away from the clamping screw is positioned axially in the region of the spring arm at a higher level than in any other part of the clamping region when no axial force is applied. In this way, it is particularly simple to apply force to the spring arm. Due to the applied force, the elastic effect of the arm is offset and, in the case of sufficient axial force, a clamping force is generated which acts radially on the transverse rod and is sufficient to achieve a rigid connection. For this purpose, the clamping surface of the clamping region, viewed in cross section, which faces the support rod, has a design which is at least partially complementary to the contour of the support rod.

[0010] The elastic mounting, in particular the material weakening causing the latter, can be positioned asymmetrically relative to the clamping screw, preferably on one side of the elastic arm, when seen in axial section. This makes it easier to match the deformation path and avoids an excessively long deformation path at the free end of the elastic arm.

[0011] Preferably, the connector can adopt a plurality of states, such as the transverse rod is already fixed in the connector, but an axial displacement along the transverse rod is still possible for the purpose of setting the positioning distance, in which the positioning distance is safely set, the radial coupling with the support rod is established, but a displacement along the support rod is still possible, which is also the final state ultimately sought, that is, the two support rods are rigidly connected to each other by the connector. In the simplest implementation of the force-applying device, the latter state is achieved by tightening the clamping screw, the earlier state corresponding to a shallower screw-in depth of the clamping screw or a state with less applied torque.

[0012] The connector can have a similar embodiment to the same embodiment (although it may have a different design during assembly, for example by the respective spring arms of the connector being directed away from each other). In a very simple design, the connector may contain only five components in total and a total of three different components (two identical receptacles, two identical clamping screws and the transverse rod). However, it can also be provided that the transverse rod and the other connector are already firmly connected to each other and fixed as one part, for example by means of a groove and a locking screw to a support rod which has been placed in the groove.

[0013] In a preferred embodiment, the two connectors each have a receptacle, which has a notch on its upper side in the axial direction, and a receptacle space in the form of a transverse continuous groove is formed in the lower end area of ​​the receptacle. Further preferably, the side area extending in the axial direction along the groove has a thread on its inner side, and the axial clamping screw interacts with the thread.

[0014] However, the invention also provides for combinations, such as transverse rods having different lengths, or connectors designed for connection to support rods having different diameters.

[0015] The connector is therefore suitable for newly implanted spinal braces and, as additional lateral reinforcement, for existing spinal braces (in this case, the lateral dimensions of the support rods may differ, depending on the patient and the system manufacturer, or on the requirements of the implant at the time).

[0016] The invention also protects the connection of such a connector and also protects the method for preparing such a connector so that it is to be used to establish a transverse connection between two support rods of a spinal support device. This can include several aspects, firstly, from the material point of view, the embodiment of the connector (provided in any case) is made of biocompatible materials (such as titanium, stainless steel or plastics, such as biocompatible polymers known to the person skilled in the art of implantology), and the obvious preparation by a sterilization step (such as autoclaving), suitable components matching the support rods of the spinal support device and / or the ready-to-use supply of the parts after assembly for the surgical operation of implantation.

[0017] Furthermore, the invention also protects an entire spinal support device having such a connector. In this case, in addition to the support rod, the spinal support device may also include an attachment mechanism for the support rod (e.g., pedicle screws of any design and their coupling mechanism), which rigidly connect a plurality of pedicle screws to the support rod via a connecting element, which, for example, allows a multi-axial adjustment (fixed coupling, multi-axially angularly configurable arrangement of the pedicle screws relative to the support rod).

[0018] In a simple configuration assuming that the support rods to be connected are approximately parallel, their extension direction, the extension direction of the transverse rod and the axial force (axial introduction direction of the clamping screw) can define a Cartesian coordinate system, but it is understood that non-orthogonal lateral positions are also possible, as are adjustable angular arrangements, although the latter may increase the minimum number of components required. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Further features, details and advantages of the invention are apparent from the following description with reference to the accompanying drawings, in which

[0020] Figure 1 shows a portion of the connector connection, precisely

[0021] Figure 1a A front view is shown, with the viewing direction being the connection direction.

[0022] Figure 1b A side view along the direction in which the support rod extends is shown, and

[0023] Figure 1c Shown with Figure 1b A cross-sectional view orthogonal to the viewing direction of

[0024] FIG. 2 shows a connector, specifically without a clamping screw in FIG. 2a and with a clamping screw in FIG. 2b, and

[0025] Figure 3 Shows Figure 2b A cross-section of a structure with force arrows drawn. DETAILED DESCRIPTION

[0026] FIG. 1 shows a receptacle 10 which, in a corresponding double embodiment, together with a clamping screw not shown in FIG. 1 (which interacts with the thread 12 of the receptacle 10 ) and together with a transverse rod 30 , forms a connector 100 , which is shown in an alternating manner in FIG. 2 b and which connects two support rods 40 a , 40 b to one another by means of a transverse reinforcement.

[0027] Although this is not Figure 2b 40a, 40b are part of a spinal support device and are rigidly connected to pedicle screws screwed into the vertebrae by suitable connectors when implanted in the human body. Such spinal support devices are known in the art and are therefore not discussed in more detail; instead, reference is made to related systems in this regard, for example in the disclosures of WO 2009 / 015100 A2 and EP 2 581 057 B1, which are incorporated by reference, respectively.

[0028] from Figure 1a It can be clearly seen from the front view that in the axial direction Z, the receptacle 10 has a recess on its upper side, and a receiving space in the form of a continuous groove along the Y direction is formed in the lower end area of ​​the recess. Figure 1a and Figure 2a It can also be seen that the transverse rod 30 can be introduced from the top along the groove and in the axial direction into the accommodation space, the accommodation space for the transverse rod being formed in the lower end region of the groove. The side region extending along the groove in the axial direction carries the thread 12 on its inner side. In the axial viewing direction Z, the groove appears as a threaded hole, which is perforated by the groove 13 in the transverse direction Y.

[0029] A receiving groove 14 extending transversely (in this exemplary embodiment orthogonally) to the groove 13 and which is more easily recognizable in FIG. 1 b is formed in the lower region of the receiver 10 relative to the axial direction Z. This receiving groove is designed to receive a support rod 40 (not shown in FIG. 1 ) and surround the latter by more than 180° in the circumferential direction. A spring arm 16, which is arranged centrally relative to the extension direction X of the support rod 40, forms a clamping region with the lateral retainer 17 opposite said spring arm, in which the support rod 40 is fixed, clamped and finally fixed firmly.

[0030] To this end, in a preferred embodiment, the constriction between the side holder 17 and the opposite lower end of the elastic arm 16 has an intermediate space that is smaller than the diameter of the support rod 40, but only slightly smaller than the diameter of the support rod 40. Thus, the clamping region 16, 17 can be clamped on the support rod 40, the elastic arm 16 being elastically deformed during the clamping movement due to its elastic mounting. The material weakening in the form of a hole 76 that crosses the receptacle 10 in the X direction facilitates the elastic mounting of the transition region of the side holder 17. Thus, in Figure 1c There is a material bridge between the lower edge of the hole 76 and the boundary portion of the groove 14 opposite thereto.

[0031] Once the receptacle 10 has been clamped onto the rod 40, it can also be removed from the rod 40 again, unless the clamping force of the clamping areas 16, 17 is very strong due to the force application means formed. By means of the clamping screw 20 in this exemplary embodiment, lifting in the radial direction is no longer possible.

[0032] As can be clearly seen from FIG. 1c and its enlarged detail, in the state where no force is applied, the horizontal plane Z16 of the upper surface 16a of the elastic arm 16 is higher in the axial direction Z by a height difference ΔZ than the horizontal plane Z17 of the upper surface of the transverse rod 30, which also forms a bearing surface for the transverse rod 30. Therefore, if the elastic arm 16 represents a movable arm and the side retainer 17 represents a fixed arm of the clamping mechanism, when an axial force is applied, it is achieved here that, under the action of the axial force, the bearing surface 16a of the movable arm is closer to the thread 12 in the axial direction Z than the bearing surface of the fixed arm 17.

[0033] If the clamping screw 30 is now screwed into the thread 12, the resulting axial force is guided by the transverse rod 30 and first acts on the bearing surface of the spring arm 16, as a result of which the spring arm 16 is pressed axially downwards, which is reflected in a radial transverse force, plotted in the Y direction in FIG. 3, due to the inner surface of the clamping area being complementary to the rod 40. In this case, the inner surface of the clamping area 16, 17 establishes a pressure contact around the rod 40 over an angular area of ​​more than 180°, preferably more than 200°, and in the present embodiment approximately 225°.

[0034] It should be understood that tightening the clamping screw 20a (i.e., applying a torque above a specified critical threshold) ensures that the support rod 40 is rigidly connected to the receptacle 10. In addition, it should be understood that due to the structural design of guiding the axial force through the transverse rod, the transverse rod 30 is also rigidly connected to the receptacle 10 during this process (this state is as shown in FIG. Figure 2b and Figure 3 shown).

[0035] During use, for example, the two receptacles 10a, 10b ( Figure 2a ) can be respectively clamped on the support rods 40a, 40b to be connected, and as Figure 2a As shown, the transverse rod 30 can be introduced into the receptacle 10a, 10b until it rests on the bearing surface 16a of the corresponding elastic arm 16 in the transverse rod channel 13. As an alternative to the design of FIG. 2, it is also possible that before the two receptacles are clamped together, the receptacles 10a, 10b can be coupled to each other by the transverse rod 30 and the clamping screw 20a by very lightly screwing the clamping screw 20 into the receptacle 10a, 10b to prevent slipping out of the channel 13 in the Z direction, so that the distance between the two connectors can still only be adjusted by displacement along the Y axis, and this distance can be appropriately adjusted relative to the distance of the support rod 40a and set by further tightening the clamping screws 20a, 20b. In this state, the connectors that have been connected to the transverse rod 30 can also be clamped together on the corresponding support rods 40a, 40b.

[0036] Further tightening then prevents the connector from loosening from the support rods 40a, 40b, but still allows a common displacement along the direction of extension X thereof to properly set the final position, wherein the connector is finally set as a rigid connection by tightening the clamping screws 20a, 20b, at the correct mutual distance and at the correct level with respect to the extent of the spine.

[0037] As is evident from the above options, managing the connection of the support bars 40a, 40b is simple and the connector requires only a few parts to use.

[0038] It is also obvious to a person skilled in the art that the structure of the receiving portion 10 of the connector is not limited to the structure of the embodiment shown in an exemplary manner.

[0039] Rather, various features of the above description and the following claims, either alone or in any combination, may be essential for implementing the invention in its various embodiments.

Claims

1. A connector (100) for connecting two support rods (40a, 40b) of a spinal support device, the support rods being placed or to be placed along a spinal column portion, The invention comprises a transverse rod (30), a first connector receptacle for connecting the transverse rod to a first support rod, and a second connector receptacle for connecting the transverse rod to a second support rod, wherein At least one connector receptacle has a clamping region for clamping the support rod with a clamping force and has an axial force (F a ), the force applying means being in the form of an axial clamping screw (20a; 20b), and the axial force being caused by screwing in said clamping screw, It is characterized in that The axial force is directed by the transverse rod; and The spring arm (16) forms the clamping area together with the side retainer (17), and the support for the transverse rod formed on the side of the transverse rod facing away from the clamping screw is axially located in the region of the spring arm at a higher level (Z16) than at the level of the side retainer (17) when no axial force is applied, whereby the axial force guided by the transverse rod first acts on the bearing surface of the spring arm (16).

2. The connector according to claim 1, It is characterized in that The clamping region can be clamped on the support rod.

3. The connector according to claim 1 or 2, It is characterized in that The resilient mounting of the resilient arm is facilitated by a material weakening (67) of the connector receptacle.

4. The connector according to claim 3, It is characterized in that The material weakening has an asymmetrical form relative to the clamping screw, seen in axial section.

5. The connector according to claim 1, It is characterized in that There is a first positioning state that can be adopted, wherein the transverse rod is maintained at a positioning distance from the support rod in the connector receptacle by the preload state of the force applying device.

6. The connector according to claim 5, It is characterized in that The positioning state can be adjusted and changed.

7. The connector according to claim 5, It is characterized in that There is an adoptable secured state in which the clamping force still permits the connector receptacle to move along the support rod, but no longer permits the connector receptacle to be lifted from the support rod.

8. The connector according to claim 7, It is characterized in that There is an adoptable state of rigid coupling between the support rod and the transverse rod, which state can be achieved by sufficient application of the force application means.

9. The connector according to claim 8, It is characterized in that This state is achieved by tightening the clamping screw.

10. The connector according to claim 1, It is characterized in that The other of the first connector receptacle and the second connector receptacle also has the features of the preceding claim.

11. The connector according to claim 10, It is characterized in that The first connector receptacle and the second connector receptacle have the same implementation form.

12. The connector according to claim 1, It is characterized in that The axial direction is perpendicular to the extension direction of the transverse rod, the axial direction is perpendicular to the extension direction of the first support rod and / or the second support rod, and / or the extension direction of the transverse rod is perpendicular to the first support rod and / or the second support rod.

13. A combination, It is characterized in that Comprising at least two connectors according to any one of claims 1 to 12, and the combination has at least two transverse bars having different lengths and / or transverse dimensions.

14. The combination according to claim 13, It is characterized in that The method comprises at least two connectors according to any one of claims 1 to 12, wherein at least two connector receptacles assigned to the two connectors have clamping areas designed for clamping support rods of different transverse dimensions.

15. A connector according to any one of claims 1 to 12, It is characterized in that Included is structure designed to direct axial forces through the transverse rod.

16. A method for preparing a connector according to any one of claims 1 to 12, It is characterized in that Made of biocompatible material, it is to be used in the transverse connection between two support rods of a spinal support device.

17. A spinal support device comprising two support rods and a connector according to any one of claims 1 to 12 for connecting the support rods.

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