DE202005007810U1 - Vertebral implant for introducing between two vertebrae comprises support plates, support elements, and a clamping device - Google Patents

Abstract

Vertebral implant (1) comprises an upper and a lower support plate (4), and two support elements (5, 6) that can be adjusted relative to each other. At least one of the support elements is hinged to a support plate. The support element has in the region of the hinged connection a bearing protrusion (7) with a spherical side surface (8). The support plate or a bearing part (9) connected to the support plate lies with a complementary contact surface on the spherical side surface over an angular region extending in the peripheral direction at least over 180[deg]. The support plate or the bearing part are mounted on the bearing protrusion so that they pivot about an axis running parallel to the support plate. A clamping device (30) clamps the bearing protrusion and the support plate or the bearing part so that they cannot pivot or releases these so that they are free to pivot about the pivot axis.

Description

The The invention relates to a vertebral body replacement implant with an upper and a lower support plate for abutment with end faces of vertebrae and with two support elements which are adjustable in their distance from one another, of which at least one is pivotally connected to a support plate.

Such a vertebral body replacement implant is for example from the DE 20311400 U1 known, the support plates are designed to pivot about an axis extending transversely to the direction of the implant axis, so that the implant occupies the smallest possible cross-section when inserted into the body and the introduction is thereby also possible through small accesses.

outgoing From this prior art, the invention is based on the object a generic vertebral body replacement implant so that on the one hand in a simple way support plates different geometry can be used and on the other hand a optimal fixing of the support plates possible on the implant will, so too size Tipping moments of the implant can be safely absorbed, such as They occur, for example, when the support plates loaded at the edge become.

These Task becomes with a vertebral body replacement implant The type described above according to the invention achieved in that the support element in the region of the articulated connection with the support plate a bearing projection with a spherical side surface that the support plate or an associated with this bearing part with a complementary to the spherical support surface formed abutment surface over a in the circumferential direction minde least over 180 ° extending angle range the side surface that the support plate and the bearing part about a pivot axis parallel to the support plate is pivotally mounted on the bearing projection and that a the Bearing projection on the one hand and the support plate or the bearing part in the contact area of the side surface or the contact surface on the other hand provided against each other clamping device is that in a clamping position the bearing projection and the support plate and the bearing member is non-pivotally clamped against each other and this in a release position releases them so that they about the pivot axis against each other are free to pivot.

By the leadership the support plate or the bearing part results in the bearing projection over spherical bearing and contact surfaces a particularly reliable guide the support plate on the support element, as well can in this area by a clamping a particularly reliable fixation of support plate can be achieved relative to the support element. It is with this arrangement readily possible, the support plate replace, it is enough the support plate or the support plate postpone, together with the bearing part, from above onto the bearing projection, a preliminary one Fixation then takes place simply by a component defining the pivot axis and a permanent fixation by the clamping device.

To the Inserting the implant between two vertebrae are the support plates freely pivotable about the pivot axis, so that their position to the desired position the vertebral body customized Once this situation is reached, it will be determined by setting the clamping device permanently maintain this position.

A particularly advantageous embodiment is obtained when the support plate U-shaped with two substantially parallel legs and one connecting them Crossbar, if continue to the legs on both sides of the spherical bearing projection are arranged when the pivot axis parallel to the transverse web runs and when the clamping device, the two legs in the clamping position at their free ends remote from the crossbar against each other stressed. In the clamping position thus clamp the two legs of the spherical bearing projection between themselves, on one side the thighs held together by the crosspiece, on the other Side through the clamping device.

The Clamping device can in particular a parallel to the pivot axis extending, applied to the free ends of the legs clamping screw be.

It is cheap, if the longitudinal axis the clamping screw and the pivot axis define a bearing plane, at a distance of an applicable to a vertebral body support surface of support plate and runs substantially parallel to this.

In a preferred embodiment it is provided that the pivot axis is defined by a bearing shaft which can be screwed into the bearing projection. Thus, although the support plate is connected via a ball joint with the bearing body before actuation of the clamping device, the degrees of freedom of the ball joint are limited by the screwed bearing shaft, so that only a pivot about a pivot axis is possible. In this case, however, the two mutually pivoted body are guided by the kuge ligen contact surfaces, that is, not all bearing forces must be transmitted through the bearing shaft, this is only to restrict the movement degrees of freedom. After pressing the Klemmvorrich tion, the forces between the support plate on the one hand and the support member on the other hand are transmitted substantially over the spherical, mutually tensioned contact surfaces and not on the bearing shaft, which can therefore be dimensioned correspondingly small.

The spherical contact surface can be attached directly to the support plate be self-formed, which then rests directly on the bearing body.

at another embodiment is between support plate and spherical bearing body inserted a special bearing part, that according to one preferred embodiment is designed as a bearing ring, along its circumference a continuous Dividing slot has. Through this separation slot, it is possible to Press together bearing ring, that is, the clamping device can clamp the bearing ring to the outside of the spherical bearing body, so that one reliable Fixation takes place.

Of the Bearing ring can be arranged in a recess of the support plate and with its outside rest against the inner wall of the recess. In particular, this will Recess a cylindrical Recess be while the bearing ring has a corresponding cylindrical outer side, so that the bearing ring inserted in a simple manner in the recess of the support plate and pulled out again can be. This facilitates the replacement of a support plate, This can be very simply deducted from a support element with bearing ring and through another will be replaced.

at a modified embodiment may the outside the bearing ring also be formed spherical and then lies on one complementary trained inner wall of the recess, so that although the bearing ring in a simple Way elastic on the bearing body can be snapped, but after the Festklemmung by the spherical design also absorb axial forces and axial moments can and thus relieves the bearing shaft

The Recess preferably forms a central opening of the support plate.

It is advantageous if the support plate is formed elastically deformable in the region of the crosspiece. This will make it possible the legs of the support plate by means of the clamping device at their free ends against each other to stretch. In this clamping of the legs of the cross bar is slightly elastic bent.

These Elastic deformability can be supported, for example, by that the support plate has a smaller thickness in the region of the transverse web than in the area the thigh.

The support plate could with their thighs and their crossbar directly on the front surfaces of the vertebra issue. But it is not necessarily ensured that the support plate on the vertebral bodies in the areas that have a particularly high strength and therefore are particularly suitable without risk of burglary of vertebra the support plate to wear.

It is therefore according to a preferred embodiment the invention provided that the legs and the crosspiece on its side facing away from the support elements outside laterally outwardly projecting, disc-shaped Wear support surfaces, the outer contour the support plate ausbildeen. In other words, at the top of the support plate by the provision of laterally projecting Support surfaces one Magnification of the Cross section of the support plate made, forming the support surfaces while a part of the support plate and are preferably in one piece connected with cross bar and thighs.

Especially It is advantageous if the two support surfaces associated with the legs are opposite outer side edges the support plate form their distance from the ventral side of the support plate becomes larger towards the dorsal side. This is the area the support plate in the dorsal area greater than in the ventral area. In the dorsal area is the carrying capacity the vertebral body greater than in the ventral area, so that in the most stable area of the vertebral body a large support plate surface for disposal stands, so in this area is the largest part of the force to be transmitted added.

It may further be provided that the outer side edges of the support plate via arcuate sections in a parallel to the crosspiece extending ventral outer edge go over the support plate. This sharp corners are avoided by the risk of burglary the support plate elevated would.

It can also be provided that the outer side edges of the support plate also over arcuate sections in a parallel to the ventral outer edge extending dorsal Outer edge of the Pass over the support plate. Overall, this results in a geometry for the support plate, which is approximately trapezoidal is and has rounded corners.

In addition, it can be provided that the middle region of the outer side edges is inwardly cambered. This inside belched Section of the outer side edges of the support plate is preferably formed arcuate.

Besides that is it cheap, when the inwardly puffed portion of the outer side edges directly to the arcuate Sections of the outer side edges connects, with which these pass into the ventral and dorsal outer edge of the support plate. These indentations expose areas of the end faces of the vertebral bodies, on the one hand less stable and therefore less suitable to take the carrying capacity, On the other hand, these allow exposed partial surfaces the faces the vertebral body the attachment of bone material and thereby the formation of bone bridges between the adjacent, from the vertebral replacement implant against each other supported Vertebral bodies.

at a further preferred embodiment is provided that the the crossbar associated support surface in her middle part one to the outer edge has an open indentation. This indentation contributes to the reduction the cross-sectional area in the region of the crosspiece and thereby promotes the elastic Deformability of the crosspiece in this area.

The The support webs associated with the transverse web and the legs preferably surround together a central opening, the dorsal outer edge is open.

Preferably is this opening circular shaped.

This opening can are formed by the recess which serves to receive a bearing part or which itself has the spherical bearing surface on the spherical Area of the bearing body is applied.

It is advantageous if the central opening via a radial slot towards the dorsal outer edge is open, so that in this area a squeezing the thigh possible is through which the support plate with the bearing body can be jammed.

Also in the dorsal outer edge the support plate can be a central, receding Be arranged portion, which is preferably formed semicircular is.

to Fixing the support plates on the front surfaces the vertebral body can protruding Fixiervorsprünge are provided, which are preferably arranged on the edge of the central opening. You are thus in the area of the face of the Vertebral body, which has a lower strength, so that these fixing projections at the plant of the support plate on the vertebral body readily into the vertebral body substance can penetrate and thereby the support surface against Rotation and displacement reliable to back up.

The fixing projections can for example, in the form of thorns or tips.

Thereby, that the Tips are arranged in the edge region of the central opening is also avoided that the fixing projections in areas of the face of the vertebral body, which have high strength, damage the vertebral body substance, this Areas therefore remain complete intact and stand the power transmission undamaged to disposal.

In the support surfaces can more Breakthroughs may be provided, the passage of bone substance serve, that is Bone substance can grow through these openings.

It is advantageous if arranged in the edge of the central opening lateral recesses are, also increase this the flexibility the support plate and promote the clampability of the support plate to the spherical bearing body.

support plates of the type described can either only be arranged on one of the two support elements, but it is readily possible to both support elements such support plates in the described Provide way. It is possible support plates to use different sizing, so that at the Top and bottom of the vertebral body replacement implant to the provided respective vortex size matched support plates can be. An exchange is easy even during the Surgery possible, if this is the surgeon for should be necessary.

The about butterfly-like shape of the support plate results in particularly favorable investment conditions on a vertebral body. A shaped support plate in this way let yourself Use in a vertebral body replacement implant with a Storage on a spherical bearing body with a defined pivot axis and a clamping device. It but understands that the Shape of this support plate also with other vertebral body replacement implants can be used, possibly also with intervertebral implants, in the interstices between two vertebrae be used and removed from this disc space intervertebral disc to replace. The invention is therefore also in a corresponding Way shaped support plate directed at itself.

It is cheap, when the bearing shaft at a support plate with bearing parts both the bearing part and an opening in the support plate interspersed. The bearing shaft then not only defines the pivot axis the assembly of support plate and bearing part relative to the spherical bearing body, but the bearing shaft then also secures the support plate against a rotation relative to the bearing part about a perpendicular the support plate standing axis.

It is advantageous if the clamping screw in its Einschraubbereich is provided with a friction-reducing coating, for example with titanium oxide, thereby the screwability is improved.

Farther It is advantageous if the support plate provided with a bone-friendly coating, for example a microporous one Coating that promotes the ingrowth of bone substance and thereby anchoring the support plate on the vertebral body favored.

on the other hand it can be cheap be, the fixation projections the support plate exempt from the bone-friendly coating so that these too after the operation are still freely moving inside the body and optimally to the vertebral body can adjust.

The following description of preferred embodiments of the invention used in conjunction with the drawings for further explanation. Show it:

1 an exploded perspective view of a vertebral body replacement implant between two vertebral bodies;

2 an enlarged perspective view of the upper support plate of the vertebral body replacement implant of 1 in a view obliquely from below on the dorsal outer edge of the support plate;

3 a view similar 2 on the ventral outer edge of the support plate with inserted into the support plate bearing ring;

4 a sectional view taken along line 4-4 in 1 in a composite vertebral body replacement implant;

5 a plan view of the support plate of the vertebral body replacement implant of 1 to 4 and

6 a view similar 3 in a vertebral body replacement implant without between support plate and support element arranged bearing ring.

The vertebral body replacement implant shown in the drawing 1 serves to between two vertebral bodies 2 . 3 to be used, which are not immediately adjacent. Either is between these two vertebral bodies 2 . 3 a vertebral body has been completely removed or has been prepared in manner not apparent from the drawing so that the vertebral body replacement implant 1 can be introduced into the interior and this interspersed, so that in other words the bridged vertebral body while still partially the vertebral body replacement implant 1 ambient exists, but is relieved in terms of its support function.

The vertebral body replacement implant 1 has at its top and on its underside each have a support plate 4 These are the same, so that below only one of the two support plates 4 is explained in more detail.

Each of the two support plates 4 is connected to a support element, one of the two support elements is as a cylinder 5 trained, the other as a piston 6 in the cylinder 5 is mounted telescopically displaceable. The displacement may be due to a filling of the cylinder 5 done with a hydraulic medium in a conventional manner, the cylinder 5 So it forms together with the piston 6 a piston-cylinder unit, through which the two parts are mutually displaceable. This displacement causes the distance of the support plates 4 at the two ends of the vertebral body replacement implant 1 can be changed.

Both the cylinder 5 as well as the piston 6 wear at their opposite ends a bearing projection 7 with a spherical or at least spherical cap bearing surface 8th , this warehouse projection 7 serves the pivotable mounting of the support plate 4 and is on the cylinder 5 and on the piston 6 each formed the same, the following description is therefore limited to the description of the storage of the upper support plate 4 on the piston 6 ,

In the embodiment of the 1 to 5 is on the stock projection 7 from above a bearing ring 9 deferred, on its inside a spherical bearing surface 10 which is complementary to the bearing surface 8th is formed and flat on this rests. The bearing ring 9 is at one point by a transverse to its circumferential direction separating slot 11 divided so that the bearing ring 9 elastically bendable to a small extent and elastically can be bent together. He can thereby on the bearing projection 7 be snapped by elastic bending and is by the spherical formation of the bearing surface 8th and the contact surface 10 held in this position after snapping.

The outside 12 of the bearing ring 9 is in the Contrary to the spherical contact surface 10 cylindrical and engages in a cylindrical recess 13 at the bottom of the support plate 4 one. The outside 12 lies on the cylindrical inside 14 this recess 13 at.

In a modified embodiment could also be provided that the outside 12 of the bearing ring 9 is formed in the manner of a spherical cap and engages in a complementary recess on the underside of the support plate. Preferably, the crown is not very strong, that is, the radii of the spherical surfaces are relatively large, so that the bearing ring must be only slightly widened to be pushed over the bearing body. In the end position then the convex outer side of the bearing ring is located on the likewise convex inner wall of the recess - after clamping results in a support in the axial direction and thus relieving the pivot bearing between bearing ring and bearing body.

The support plate 4 points in its lower, the piston 6 facing part two parallel side by side and at a distance from each other extending legs 15 . 16 on, over an approximately semicircular crosspiece 17 are connected to each other, while in the upper part facing the respective vertebral body plate-shaped, laterally over the legs 15 and 16 as well as the crossbar 17 protruding support surfaces 18 . 19 . 20 are arranged. These support surfaces are preferably integral with the legs 15 . 16 and the crossbar 17 connected. The two support surfaces 18 and 19 lie above each one leg 15 . 16 and are assigned to this, the support surface 20 runs above the crossbar 17 and is assigned to this.

The thigh 15 and 16 as well as the crossbar 17 on the one hand and their associated support surfaces 18 . 19 . 20 On the other hand, together surround the circular recess 13 holding the support plate 4 completely interspersed and the inclusion of the bearing ring 9 serves. However, the support surfaces extend 18 . 19 . 20 radially inwardly into this recess 13 and thus form a cross section of the recess 13 narrowing ring shoulder 21 out, as a stop the immersion depth of the bearing ring 9 into the recess 13 limited.

In both thighs 15 . 16 are located in the transition region to the semicircular crosspiece 17 aligned with each other, transverse to the longitudinal direction of the legs 15 . 16 running holes 22 . 23 that with appropriate holes 24 . 25 in the bearing ring 9 are alignable.

In the spherical bearing projection 7 is a transverse to the longitudinal direction of the piston 6 and in the radial direction threaded bore 26 incorporated, in which a bearing screw 27 can be screwed. Through this bearing screw 27 becomes the movement of the bearing ring 9 and thus the support plate 4 relative to the spherical bearing projection 7 restricted, namely, the movement is on a pivoting movement about the longitudinal axis of the bearing screw 27 limited.

In the preferred embodiment it is provided that each bearing projection 7 only one threaded hole 26 has, so that only one side of the bearing projection 7 a bearing screw 27 is screwed through the symmetrical design of the support plate 4 with corresponding holes 22 and 23 on opposite sides and a corresponding formation of the bearing ring 9 However, it is possible that the support plate 4 with the bearing ring 9 optionally on the upper side or on the lower side of the vertebral body replacement implant 1 with a corresponding bearing projection 7 pivotally connected as in the preferred embodiment, the threaded holes 26 the bearing protrusions 7 at the top and bottom of the vertebral body replacement implant 1 are arranged on the same side.

Through the bearing screw 27 becomes the bearing ring 9 in a defined manner and captive with the respective bearing projection 7 connected. The support plate 4 can be easily replaced, this can in fact be from the bearing ring 9 Pull off and replace with another support plate if necessary. It is also possible after removing the support plate, the bearing ring 9 from the bearing projection 7 it is sufficient to widen it slightly elastically.

One of the two thighs 15 . 16 carries at its free end a parallel to the holes 22 . 23 running through eyelet 28 , the other leg a aligned, internally threaded bore aligned therewith 29 , In this internally threaded hole 29 can one through the Durchstecköse 28 inserted clamping screw 30 are screwed in, when screwing the free ends of the two legs 15 . 16 against each other spans. These are with the inside 14 the recess 13 against the outside 12 of the bearing ring 9 strained and push this in turn together, so that the bearing ring 9 with its contact surface 10 clamped against the storage area 8th of the bearing projection 7 is tense. This leads to a complete definition of the component of support plate 4 and bearing ring 9 relative to the bearing projection 7 , the pivoting is thus repealed.

The thigh 15 . 16 are slightly bent elastically, and to support this bendability are in the annular shoulder 21 several semicircular recesses 31 provided, except in the crossbar 17 associated support surface 20 a central, substantially semicircular recess 32 , and finally in the crossbar 17 a semi-circular in cross-section return 45 as well as in the thighs 15 . 16 also in cross-section semicircular recesses 46 , These recesses lead to a weakening in this area and thereby increase the elastic deformability of the overall U-shaped support plate 4 ,

The ring shoulder 21 carries on its outside several mandrel-shaped Fixiervorsprünge 33 , so these are directly on the edge of the central recess 13 arranged while the remaining parts of the support surfaces 18 . 19 . 20 are free from such fixing projections.

The outer contour of the support plate is determined by the outer contour of the support surfaces 18 . 19 and 20 , The support surface 20 that the crossbar 17 is assigned has a straight ventral outer edge 34 on, the only of the central return 32 is interrupted and parallel to the longitudinal axis of the bearing screw 27 runs. The outer edge 34 goes by means of a bent section 35 over into lateral outer edges 36 the support surfaces 19 and 20 , These lateral outer edges 36 are formed once from a part of the curved section 35 followed by an inwardly inflated arcuate section 37 and finally through an outwardly bent section 38 which is in a dorsal outer edge 39 ends, which are parallel to the ventral outer edge 34 runs. In the central part of the dorsal outer edge 39 There is a semicircular return 40 that has a slot 41 with the recess 13 is in communication, that is the recess 13 is over this slot 41 to the return 40 open. This is how the curved section goes 38 at its end at right angles in the return 40 above.

The support surfaces 18 . 19 and 20 thus tension an airfoil, which is narrower in the ventral part than in the dorsal part. In other words, the distance between the lateral outer edges increases 36 from the ventral side to the dorsal side, so that overall results in an approximately trapezoidal base with rounded outer edges and with arcuate indentations 42 on opposite sides. This gives a butterfly-like outer contour for this wing. The wing areas are selected so that they come to rest on the parts of the support surface of a vertebral body, which is particularly sustainable, so that the risk of break-in of the support plates 4 can be minimized.

In the support surfaces 18 . 19 . 20 are additionally perforations 43 provided, which serve bone growth, so that bone substance in this area through the support surfaces 18 . 19 . 20 can grow through.

While in the embodiment of the 1 to 4 the support plate 4 with intermediate storage of a bearing ring 9 on the bearing projection 7 is stored, is in the embodiment of the 6 , which is otherwise built the same as that of 1 to 4 and in the same parts therefore bear the same reference numerals, dispenses with the bearing ring. Instead, the inside becomes 14 the recess 13 in a similar way as the bearing ring 9 at its contact surface 10 spherically formed and to the storage area 8th of the bearing projection 7 adapted, so that the support plate 4 with the inside 14 directly on the bearing projection 7 is applied.

For insertion of the vertebral body replacement implant 1 this is preassembled outside the body. These are the desired support plates 4 with the necessary geometries, optionally with the interposition of the bearing ring 9 , on the bearing projection 7 placed. In collapsed condition, so when completely in the cylinder 5 inserted piston 6 , is the vertebral body replacement implant 1 inserted into the space in which a vortex is to be replaced or bridged, so that the support plates 4 the vertebral bodies to be supported 2 . 3 face. The orientation is chosen so that by the bearing screw 27 defined pivot axis in a medial-lateralalerer direction, the dorsal outer edges 39 show in the dorsal direction, the ventral outer edges 34 in ventral direction.

In one embodiment, without between the support plate 4 and the bearing projection 7 arranged bearing ring forms the bearing screw 27 not quite a defined bearing axis, but she sticks her head in the recesses 46 the leg into and thereby restricts the pivoting of the support plate relative to the bearing projection. In this way, a pivotability of the support plate is also in this embodiment substantially 4 opposite the bearing projection 7 one through the longitudinal axis of the bearing screw 27 defined bearing axis given.

Via a connection line 44 is then in unspecified manner, a hydraulic medium, for example, a saline solution in the interior of the cylinder 5 introduced so that thereby the piston 6 out of the cylinder 5 is ejected. The freely pivotable about its pivot axis support plates 4 attach themselves to the vertebral body to be supported 2 . 3 and adapt to their respective orientation. Once the necessary distance is reached, the vertebral body replacement plan becomes did fix.

A fixation takes place once with respect to the distance from the piston 6 and cylinders 5 , these two parts are by an unspecified clamping device 45 clamped against each other, so that they are no longer mutually displaceable.

Furthermore, the clamping screw 30 with a predetermined maximum torque in the internally threaded bore 29 screwed in and thus tense the two legs 15 . 16 against the bearing ring 9 or optionally directly against the bearing projection 7 , so that the pivotability of the support plate 4 opposite the bearing projection 7 completely removed. Due to the spherical formation of the bearing projection 7 as well as the storage area 8th of the bearing ring 9 or the inside 14 the recess 13 in one embodiment without bearing ring of the bearing projection 7 includes circumferentially strong, so that not only the pivoting is prevented, but there will also be a determination in the axial direction. This relieves the bearing screw 27 , A significant portion of the axial forces and / or the angrei fenden moments is through this clamping on the clamping screw 30 added.

This gives a secure fixing of the support plates 4 relative to the bearing protrusions 7 and the two supporting elements pistons 6 and cylinders 5 in terms of the distance between the two support plates 4 , In this form, the vertebral body replacement implant 1 remain in the body and take over the support function, if necessary, by embedding of bone material, a bony surrounding the vertebral body replacement implant 1 be encouraged so that a bony bridge between the through the vertebral body replacement implant 1 supported vertebral bodies 2 and 3 can result.

Claims (32)

Vertebral body replacement implant having an upper and a lower support plate for abutment on end faces of vertebral bodies and having two support elements which are adjustable in their spacing, at least one of which is articulated to a support plate, characterized in that the support element ( 5 . 6 ) in the region of the articulated connection with the support plate ( 4 ) a bearing projection ( 7 ) with a spherical side surface ( 8th ), that the support plate ( 4 ) or a bearing part connected thereto ( 9 ) with a complementary to the spherical side surface ( 8th ) trained contact surface ( 14 . 10 ) over an angular range extending at least over 180 ° in the circumferential direction on the side surface ( 8th ) is applied, that the support plate ( 4 ) or the bearing part ( 9 ) around a parallel to the support plate ( 4 ) extending pivot axis pivotally mounted on the bearing projection ( 7 ) is mounted and that a bearing projection ( 7 ) on the one hand and the support plate ( 4 ) or the bearing part ( 9 ) in the contact area of the side surface ( 8th ) or the contact surface ( 14 . 10 ) On the other hand, clamping device against each other ( 30 ) is provided, which in a clamping position the bearing projection ( 7 ) and the support plate ( 4 ) or the bearing part ( 9 ) unverschwenkbar against each other and releases them in a release position, so that they are free to pivot about the pivot axis against each other. Implant according to claim 1, characterized in that the support plate ( 4 ) Is U-shaped with two substantially parallel legs ( 15 . 16 ) and a transverse web connecting them ( 17 ), that the legs ( 15 . 16 ) on both sides of the spherical bearing projection ( 7 ) are arranged such that the pivot axis parallel to the transverse web ( 17 ) and that the clamping device ( 30 ) the two legs ( 15 . 16 ) in the clamping position at its from the crosspiece ( 17 ) spaced free ends against each other. Implant according to claim 2, characterized in that the clamping device ( 30 ) extending parallel to the pivot axis, at the free ends of the legs ( 15 . 16 ) is applied clamping screw. Implant according to claim 3, characterized in that the longitudinal axis of the clamping screw and the pivot axis define a bearing plane spaced at a distance from one to a vertebral body ( 2 . 3 ) can be applied support surface of the support plate ( 4 ) and runs substantially parallel to this. Implant according to one of the preceding claims, characterized in that the pivot axis by a bearing shaft ( 27 ) defined in the bearing projection ( 7 ) can be screwed. Implant according to one of the preceding claims, characterized in that the bearing part as a bearing ring ( 9 ) is formed, which has a transverse to its circumference separating slot ( 11 ) having. Implant according to claim 6, characterized in that the bearing ring ( 9 ) in a recess ( 13 ) of the support plate ( 4 ) is arranged and with its outside ( 12 ) on the inner wall ( 14 ) of the recess ( 13 ) is present. Implant according to claim 7, characterized in that the recess ( 13 ) a central opening of the support plate ( 4 ). Implant according to one of claims 2 to 8, characterized in that the support plate ( 4 ) in the Area of the crossbar ( 17 ) is formed elastically deformable. Implant according to claim 9, characterized in that the support plate ( 4 ) in the region of the crosspiece ( 17 ) has a smaller thickness than in the region of the legs ( 15 . 16 ). Implant according to one of claims 2 to 10, characterized in that the limbs ( 15 . 16 ) and the crosspiece ( 17 ) at her from the support elements ( 5 . 6 ) facing away from the outside laterally outwardly projecting, plate-shaped support surfaces ( 18 . 19 . 20 ) carrying the outer contour of the support plate ( 4 ) train. Implant according to claim 11, characterized in that the two legs ( 15 . 16 ) associated support surfaces ( 18 . 19 ) opposite, outer side edges ( 36 ) of the support plate ( 4 ) whose distance from the ventral side ( 34 ) of the support plate ( 4 ) to its dorsal side ( 39 ) becomes larger. Implant according to claim 12, characterized in that the outer side edges ( 36 ) of the support plate ( 4 ) over arcuate sections ( 35 ) in a parallel to the crosspiece ( 17 ) extending ventral outer edge ( 34 ) of the support plate ( 4 ) pass over. Implant according to claim 12 or 13, characterized in that the side edges ( 36 ) over arcuate sections ( 38 ) into a dorsal outer edge ( 39 ) of the support plate ( 4 ) pass over. Implant according to one of claims 12 to 14, characterized in that the middle region ( 37 ) of the outer side edges ( 36 ) is inwardly cambered. Implant according to claim 15, characterized in that the area (2) dipped inwards ( 37 ) of the outer side edges ( 36 ) of the support plate ( 4 ) is arcuate. An implant according to claim 15 or 16, characterized in that the area implanted inside ( 37 ) of the outer side edges ( 36 ) directly to the arcuate sections ( 35 . 38 ) of the outer side edges ( 36 ), with which these in the ventral and dorsal outer edge ( 34 . 39 ) of the support plate ( 4 ) pass over. Implant according to one of claims 11 to 17, characterized in that the crosspiece ( 17 ) associated support surface ( 20 ) in its middle part one to the ventral outer edge ( 34 ) open registration ( 32 ) having. Implant according to one of claims 11 to 18, characterized in that the crosspiece ( 17 ) and thighs ( 15 . 16 ) associated support surfaces ( 20 . 18 . 19 ) together have a central opening ( 13 ), which lead to the dorsal outer edge ( 39 ) is open. Implant according to claim 19, characterized in that the opening ( 13 ) is circular. Implant according to claim 19 or 20, characterized in that the central opening ( 13 ) via a radial slot ( 41 ) to the dorsal outer edge ( 39 ) is open. Implant according to one of claims 11 to 21, characterized in that in the dorsal outer edge ( 39 ) of the support plate ( 4 ) a central, receding portion ( 40 ) is arranged. Implant according to claim 22, characterized in that the recessed portion ( 40 ) is semicircular. Implant according to one of claims 19 to 23, characterized in that on the edge ( 21 ) of the central opening ( 13 ) outwardly projecting Fixiervorsprünge ( 33 ) are arranged. Implant according to claim 24, characterized in that the fixing projections ( 33 ) have the form of thorns or spikes. Implant according to one of claims 11 to 25, characterized in that in the support surfaces ( 18 . 19 . 20 ) Breakthroughs ( 43 ) are provided. Implant according to one of claims 19 to 26, characterized in that in the edge ( 21 ) of the central opening ( 13 ) lateral recesses ( 31 ) are arranged. Implant according to one of the preceding claims, characterized in that both support elements ( 5 . 6 ) with support plates ( 4 ) of the type described are connected. Implant according to one of claims 5 to 28, characterized in that the bearing shaft ( 27 ) at a support plate ( 4 ) with bearing parts ( 9 ) both the bearing part ( 9 ) as well as an opening ( 22 . 23 ) in the support plate ( 4 ) interspersed. Implant according to one of claims 5 to 29, characterized in that the clamping screw ( 27 ) is coated in its Einschraubbereich with titanium oxide. Implant according to one of the preceding claims, characterized in that the support plate ( 4 ) is provided with a bone-friendly coating. Implant according to claim 31, characterized in that the fixing projections ( 33 ) of the support plate ( 4 ) are excluded from the bone-friendly coating.