DE20112123U1 - Facet joint implant - Google Patents

Description

A 56 230 u Aesculap AG & Co. KG

&zgr; - 223 Am Aesculap Platz

13 July 2001 78532 Tuttlingen

Facet joint implant

The invention relates to a facet joint implant for arthrodesis of a joint space and two facets
comprehensive facet joint, whereby the two facets
each having a facet surface facing the other, with at least one fixing element.

Usually, movement segments of the spine are repaired using bone chips or so-called
Cages are fused, with additional dorsal fixation using an internal fixator to stabilize the fusion.

Another, relatively complicated possibility of
dorsal fixation is provided by the translaminar facet blocking
using osteosynthesis screws according to Magerl.

Facet joint implants of the type described above are used in particular for facet joint arthrodesis
of ventral or trans- or extraforaminal vertebral body fusions, whereby the former provides additive dorsal stabilization.

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Furthermore, such implants are used in the treatment of spondylarthrosis with simultaneous hypomobility and a greatly reduced intervertebral space. The facet joint implants are used alone, i.e. without the use of a ventral instrumentation system.

Facet joint implants made of shape memory alloys, such as those disclosed in particular in EP 0 646 353 A1 and EP 0 743 045 A2, are known as osteosynthesis clamps. The disadvantage of these clamps is that the materials selected must be subjected to heat treatment during the operation in order to convert the clamp into its original shape, in which it can block the facet joint.

Furthermore, DE 33 10 833 C2 discloses a staple which has two legs connected by a bar, each of which can be hammered into a facet. When such staples are inserted, there is maximum stress in the area of the bar, so that it must be designed to be particularly stable. In addition, this implant can easily twist.

Therefore, it is an object of the present invention to improve a facet joint implant of the type described above so that it can be more easily inserted into a joint gap between two vertebral bodies.

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This object is achieved according to the invention in a facet joint implant of the type described above in that the at least one fixing element has at least a first and a second surface and that the first and the second surface can be brought into surface contact with at least one facet.

Such an implant can be inserted directly into the joint space and thereby directly prevents the two facets from moving towards each other. It can therefore be designed to be particularly torsionally rigid. Alternatively, it is also possible to insert the fixing element into the two facets across the joint space, so that each surface rests approximately half on or in one facet and half on the other facet. With such an application, the movement parallel to the joint space is then fixed in particular. In addition, such a facet joint implant is particularly simple and inexpensive to manufacture.

It is advantageous if two fixing elements are provided and if one of the two fixing elements penetrates the other fixing element in a transverse direction. In such a design, one fixing element can be introduced directly into the joint gap to prevent movement of the facets transversely to the joint gap. The other fixing element is arranged transversely to the first fixing element and thus also transversely to the joint gap, so that it, for example in the form of two protruding flaps or wings, penetrates the facets and prevents movement of the same parallel to the

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This prevents the joint gap from closing. This allows complete stabilization of the facet joint.

According to a preferred embodiment of the invention, it can be provided that the at least one fixing element has surfaces oriented essentially parallel to the facet surfaces and can be introduced between the facet surfaces. With this implant, the joint gap can be filled almost completely and thus blocked, whereby the implant offers minimal attack surfaces for twisting thereof.

Preferably, the at least one fixing element is arranged on a substantially U-shaped clamp, wherein the clamp comprises two legs and a crossbar connecting the two legs. The implant therefore comprises a U-shaped clamp in addition to the fixing element, which further strengthens the fixation of the facet joint.

According to a further preferred embodiment of the invention, it can be provided that the at least one fixing element is arranged on the crossbar. In this way, the implant can be fixed to the facet joint particularly easily, namely by driving in the clamp, whereby the fixing element is simultaneously fixed to the facets.

Advantageously, the at least one fixing element is arranged on at least one of the two legs.

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In this design, too, the fixing element is attached to the facet joint in a simple manner in conjunction with the clamp.

It is advantageous if the at least one fixing element is arranged on the clamp essentially parallel to a plane defined by the legs and the crossbar. If the clamp is used across the joint space, the fixing element is automatically inserted across the joint space, whereby the clamp also prevents movement of the facet joint in a direction across the joint space.

Furthermore, it is advantageous if the at least one fixing element is arranged on the clamp essentially transversely to a plane defined by the legs and the crossbar. In this way, the fixing element can be easily inserted into the joint gap, with the clamp simultaneously bridging the joint gap and fixing the facets relative to one another.

It is particularly advantageous if at least one of the two legs has a recess in the surface of the leg. This makes it easier to insert the staples and creates a positive fit when implanted, because the bone can remain in the recess. This prevents the staples from becoming loose.

It is particularly advantageous if the depression is in the longitudinal direction of at least one of the two tendons.

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When the staple is inserted, the bone remains in the groove, thus creating a positive connection that prevents the staple from coming loose.

It is advantageous if the two legs have free ends and if cutting edges are provided at the free ends. A staple provided with cutting edges in this way can be anchored particularly securely in a bone because the cutting edges easily penetrate the bone and prevent the staple from coming loose.

To prevent the clamp from coming loose from the bone, anchoring elements protruding towards the facets are provided on at least one of the two legs.

The facet joint implant has a particularly high level of stability if the crossbar and/or at least one of the two legs have a substantially rectangular cross-section.

To insert the implant, it is advantageous if it comprises a tool holder for connection to an insertion tool. The implant can be held and inserted by such a tool, which corresponds to the tool holder in any way.

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In principle, the tool holder can be arranged at any point on the implant, but it is preferably arranged on the clamp. This design enables particularly simple and safe insertion of the implant with a clamp.

In order to enable particularly easy handling of the implant, the tool holder comprises at least one angled projection pointing away from the implant.

Preferably, the first and second surfaces of the at least one fixing element that are in contact with at least one facet are concavely curved in the direction of the associated facet surface. This optimally fills the joint gap and at the same time minimizes movement parallel to the joint gap, in particular even when only a single fixing element is provided.

The at least one fixing element is particularly easy to manufacture if it comprises a plane-parallel plate.

It is also advantageous that at least one fixing element has a wedge shape. This additionally stabilizes the facet joint.

Preferably, the at least one fixing element is conical or multi-conical. This creates a

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An additional clamping of the implant in the area of the joint space is achieved.

It is particularly advantageous if the at least one fixing element has a curvature adapted to at least one of the two facets. A fixing element shaped in this way can at least partially encompass one of the two facets and thus increase a contact surface on one of the two facets, which ultimately leads to a stabilization of the joint.

In a further preferred embodiment of the invention, it can be provided that anchoring elements protruding in the direction of the facets are provided on the at least one fixing element. The anchoring elements create additional connections between the implant and the bone parts, which in turn stabilizes the joint.

The anchoring elements are preferably designed in the form of cutting edges, teeth or ribs. These are easy to manufacture and ensure an optimal connection between the implant and the bone parts.

According to a further preferred embodiment of the invention, it can be provided that the at least one fixing element has two ribs that protrude laterally essentially transversely to a plane defined by the at least one fixing element. In particular, when the fixing element is inserted into the joint gap and fills it, the laterally protruding

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adjacent ribs into neighboring bone parts and additionally fix the implant in the joint space.

In order to allow bone to grow through the implant, at least one fixing element can be provided with openings.

In a further preferred embodiment of the invention, at least one fastening element receptacle can be provided on the implant. Such an implant can be fixed to the facet joint with additional fastening elements, for example with screws, nails, staples or the like penetrating the fastening element receptacle.

Preferably, at least one stabilization stop is provided on the implant to stabilize the fixation element in the joint space. This prevents the implant from penetrating too far into the joint space or from emerging from it again.

It is advantageous if the stabilization stop comprises two projections arranged on the front surfaces of the fixing element and projecting in the same direction. This means that, for example, one of the two facets can be encompassed by the fixing element on both sides with the two projections, which results in stabilization in particular when the fixing element is inserted to fill the joint gap.

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To increase stability and simplify manufacturing, the implant can be molded in one piece.

To promote bone growth onto the implant, the implant may have a surface with a microstructure and/or a bioactive coating.

Preferably, the implant is made of an X-ray transparent material. This means that the implant is invisible when the human body is examined with X-rays and does not prevent the view of neighboring bone parts.

It is particularly advantageous if the implant is made of TiA16V4 or NiTiNoI.

The following description of preferred embodiments of the invention serves to explain in more detail in conjunction with the drawing. They show:

Figure 1: a side view of a first embodiment of an implant inserted in a joint space;

Figure 2: a view along line 2-2 in Figure 1;

Figure 3: a view similar to Figure 1 of a second embodiment of an implant;

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Figure 4: a view along line 4-4 in Figure 3;

Figure 5: a view similar to Figure 1 of a third embodiment of an implant;

Figure 6: a view along line 6-6 in Figure 5;

Figure 7: a view similar to Figure 1 of a fourth embodiment of an implant;

Figure 8: a view along line 8-8 in Figure 7;

Figure 9: a view of the implant in the direction of arrow A in Figure 8.

Figure 10: a view similar to Figure 9 of a fifth embodiment of an implant;

Figure 11: a view similar to Figure 8 of a sixth and a seventh embodiment of an implant;

Figure 12: a cross-sectional view taken along line 12-12 in Figure 11;

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Figure 13: a view similar to Figure 4 of an eighth embodiment of an implant; and

Figure 14: a cross-sectional view taken along line 14-14 in Figure 13.

Figures 1 and 2 show an implant for facet joint arthrodesis, which is provided with the reference numeral 100 as a whole and is inserted into a joint gap 110 of a facet joint 112, which is formed by a bony articular process of a vertebral body 120 which projects in the direction of an adjacent vertebral body 114 and forms a first facet 116, as well as by a bony process of the vertebral body 114 which points towards the vertebral body 120 and forms a second facet 118.

The joint space 110 of the facet joint 112 runs approximately parallel to a spine of a human body defining a longitudinal direction and comprising the vertebral bodies 114 and 120.

To block the facet joint 112, the implant 100 is inserted into the joint gap 110. It comprises a base body 130 designed as a fixing element, which is essentially made of a rectangular, slightly wedge-shaped plate, which has a curved shape over approximately half its width in the direction of its end with a thinner cross section. In the cross section, as shown in Figure 2

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The shape of the base body 130 is reminiscent of the
Letter J. Approximately centrally is a hole 132 on the
Base body 130 arranged to receive a fastening element in the form of a bone nail 134
serves.

Flush with the front edges 136 and 137 of the base body, parallel protruding tabs 140 and 141 are arranged transversely to the base body 130, which extend from a concave
curved surface 144.

The facet joint 112 is blocked with the implant 100 by inserting the base body 130 into the joint space
110 is inserted so that it almost completely
and the second facet 118 due to
its curvature partially encompasses. The two lobes
140 and 141 lie laterally on the first facet 116 when inserted and delimit it between them. The bone nail 134 is, when the implant has taken its final position, fixed by the
Hole 132 and into the second facet 118
struck.

Another implant 200 is shown in Figures 3 and 4. It comprises a base body 230 which
Base body 130 of the implant 100. However,
No lateral tabs 140 or 141 are provided, but a transverse to the base body 230 at the
boundary plate 250 which is arranged on the longitudinal edge not adjoining the curved region and which has a convex curvature pointing away from the longitudinal edge 246.

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It is arranged in such a way that two lateral fastening flaps are formed, each of which is provided with a bore 232 and 233, respectively. The implant 200 is fixed to the first facet 216 and to the second facet 218 using two bone nails 234 and 235 when the base body 230 is inserted into the joint gap 210.

A third embodiment of an implant according to the invention is provided with the reference number 300 in Figures 5 and 6. It has a wedge-shaped, non-curved base body 330 on which a limiting plate 350 is arranged in a manner analogous to the implant 200. Instead of the holes 232 and 233, two mandrels 352 and 353 protruding in the direction of the first facet 316 and the second facet 318 are arranged on the limiting plate 350, specifically on a surface 355 of the limiting plate 350, which is concavely curved in the direction of the joint gap 310. The mandrels 352 and 353 are cylindrical in the area of the limiting plate 350 and taper conically towards their free ends.

The implant 300 is inserted into the joint space 310 by inserting the base body 330 into the joint space 310 and driving the mandrels 352 and 353 into the first facet 316 and the second facet 318, respectively.

Due to the curvature of the limiting plate 350, the mandrels 352 and 353 are not parallel to the limiting plate.

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tongue plate 350 so that when inserted they form a clamp-like fixation of the facet joint 312.

Figures 7 to 9 show a fourth embodiment of an implant, which is provided with the reference number 400 overall. It is the simplest form of a facet joint implant for arthrodesis and consists essentially of a single fixing element forming a base body 430. The base body 430 essentially comprises a cuboid-shaped plate, the two largest side surfaces 458 and 459 of which extend in the longitudinal direction and are concavely curved in a direction running transversely to the longitudinal direction 460, so that the base body 430 has approximately the shape of a dog bone in longitudinal section.

To block the facet joint 412, the implant 400 is inserted into the joint space 410 in such a way that the concavely curved side surfaces 458 and 459 each rest against surfaces of the first facet 416 and the second facet 418, which have a slightly convex curvature.

The implant 400 can additionally be provided with transverse bores 464 arranged transversely to the longitudinal direction 460 and penetrating the concave side surfaces 458 and 459, which allow bone to grow through or alternatively serve to receive fastening elements such as nails or screws.

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An implant similar to the implant 400 is provided with the reference number 500 in Figure 10. On the base body 530, which is shaped analogously to the base body 430, two symmetrically arranged fixing plates 566 and 567 are attached, which protrude from the concave side surfaces 558 and 559 transversely to the longitudinal direction 560 and extend over the entire width of the base body 530 and define a common plane. In a direction transverse to the longitudinal direction 560, the fixing plates each have a width of approximately one third of the extension of the base body 530 in the longitudinal direction 560.

The implant 500 is inserted into the joint space 510 by pushing it in and driving the fixation plates 566 and 567 into the first facet 516 and the second facet 518. In this way, the implant 500 is secured in the two facets 516 and 518, respectively, by means of the fixation plates 566 and 567.

Figure 11 shows an implant, which is provided with the reference numeral as a whole and comprises two fixing plates 666 and 667 designed as fixing elements. These are each arranged on a substantially U-shaped bracket 670, namely on its substantially parallel legs 672 and 673, whereby the leg 673 is only approximately two thirds the length of the leg 672. The fixing plates are attached to the legs 672 and 673 in a direction towards each other, pointing away from them and run parallel to one of the legs 672 and 673 and a

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connecting and convexly curved transverse web 674.

The legs 672 and 673 and the crosspiece 674 have a substantially rectangular cross-section. The legs 672 and 673 are each provided with a projection 676 and 677 which protrudes in the direction of the other leg and forms an anchoring element. Furthermore, the free ends 678 and 679 are bevelled so that a cutting edge is formed. The legs 672 and 673 are also each provided with a longitudinal groove 680 and 681 on their outer surfaces so that the longitudinal grooves 680 and 681 open away from each other.

The legs 672 and 673 are extended beyond the crosspiece 674 and are each provided with an angled retaining projection 882 or 883 pointing towards the other, which can be grasped by an insertion tool (not shown) for inserting the implant 600.

The implant 600 is inserted across the joint gap 610 to block the facet joint 612 by driving a leg 672 or 673 into the first facet 616 or the second facet 618, respectively. The two fixing plates 666 and 667 are then each oriented transversely to the joint gap 610.

An alternative embodiment of the implant 600 is provided with the reference numeral 700 in Figures 11 and 12. This seventh embodiment

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comprises a clamp 770 which is essentially identical to the clamp 670 described in connection with the implant 600, but does not have any fixing plates 666 or 667. Rather, a locking plate 785 which is similar to the base body 430 of the implant 400 is arranged on the crosspiece 774 parallel to the legs 772 and 773 in the direction of their free ends 778 and 779. The thickness of the locking plate 785 corresponds at most approximately to the thickness of the clamp 770. Furthermore, the locking plate 785 lies in the plane defined by the clamp 770.

In principle, the implant 700 is used in a similar manner to the implant 600 for blocking the facet joint 712. However, the type of blocking differs in that the blocking plate 785 penetrates transversely to the joint gap 710, bridging it partially into the first facet 716 and partially into the second facet 718.

An eighth and final embodiment is shown in Figures 13 and 14. It includes all the features of the implant 700, but differs from it in the arrangement of the locking plate 885. Unlike the implant 700, this is arranged transversely to a plane defined by the clamp 870 on the crosspiece 874.

If the implant 800 is inserted into the joint space 810, the locking plate 885 at least partially fills the joint space 810, the legs 872

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and 873 of the clamp 870 fix the locking plate 885 when they are each hammered into one of the two facets 816 or 818.

All implants 100 to 800 can have a surface with a microstructure and/or a bioactive coating. They can be made of an X-ray transparent material or of TiA16V4 or NiTiNoI.

Furthermore, all implants 100 to 800 are made in one piece.

Claims (32)

1. Facet joint implant for arthrodesis of a facet joint comprising a joint space and two facets, the two facets each having a facet surface facing the other, with at least one fixing element, characterized in that the at least one fixing element ( 130 ; 230 ; 330 ; 430 ; 530 ; 666 , 667 ; 785 ; 885 ) has at least a first and a second surface ( 144 , 145 ; 244 , 245 ; 344 , 345 ; 458 , 459 ; 558 , 559 ; 658 , 659 ; 758 , 759 ; 858 , 859 ) and that the first and the second surface ( 144 , 145 ; 244 , 245 ; 344 , 345 ; 458 , 459 ; 558 , 559 ; 658 , 659 ; 758 , 759 ; 858 , 859 ) can be brought into surface contact with at least one facet ( 116 , 118 ; 216 , 218 ; 316 , 318 ; 416 , 418 ; 516 , 518 ; 616 , 618 ; 716 , 718 ; 816 , 818 ). 2. Implant according to claim 1, characterized in that two fixing elements ( 530 , 566 , 567 ) are provided and that one ( 566 , 567 ) of the two fixing elements ( 530 , 566 , 567 ) penetrates the other fixing element ( 530 ) in a transverse direction. 3. Implant according to claim 1 or 2, characterized in that the at least one fixing element ( 130 ; 230 ; 330 ; 430 ; 530 ; 885 ) has surfaces ( 144 , 145 ; 244 , 245 ; 344, 345 ; 458 , 459 ; 558 , 559 ; 858 , 859 ) oriented substantially parallel to the facet surfaces and can be introduced between the facet surfaces. 4. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 666 , 667 ; 785 ; 885 ) is arranged on a substantially U-shaped clamp ( 670 ; 770 ; 870 ) and that the clamp ( 670 ; 770 ; 870 ) comprises two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ) and a transverse web ( 674 ; 774 ; 874 ) connecting the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ). 5. Implant according to claim 4, characterized in that the at least one fixing element ( 785 ; 885 ) is arranged on the transverse web ( 774 ; 874 ). 6. Implant according to one of claims 4 or 5, characterized in that the at least one fixing element ( 666 , 667 ) is arranged on at least one of the two legs ( 672 , 673 ). 7. Implant according to one of claims 4 to 6, characterized in that the at least one fixing element ( 666 , 667 ; 785 ) is arranged on the clamp ( 670 ; 770 ) substantially parallel to a plane defined by the legs ( 672 , 673 ; 772 , 773 ) and the transverse web ( 674 ; 774 ). 8. Implant according to one of claims 4 to 7, characterized in that the at least one fixing element ( 885 ) is arranged on the clamp ( 870 ) substantially transversely to a plane defined by the legs ( 872 , 873 ) and the transverse web ( 874 ). 9. Implant according to one of claims 4 to 8, characterized in that at least one of the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ) comprises a recess ( 680 , 681 ; 780 , 781 ; 880 , 881 ) arranged in a leg surface. 10. Implant according to claim 9, characterized in that the recess comprises a groove ( 680 , 681 ; 780 , 781 ; 880 , 881 ) extending in the longitudinal direction of at least one of the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ). 11. Implant according to one of claims 4 to 10, characterized in that the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ) have free ends ( 678 , 679 ; 778 , 779 ; 878 , 879 ) and that cutting edges are provided at the free ends ( 678 , 679 ; 778 , 779 ; 878 , 879 ). 12. Implant according to one of claims 4 to 11, characterized in that anchoring elements ( 676 , 677 ; 776 , 777 ; 876 , 877 ) projecting in the direction of the facets ( 616 , 618 ; 716 , 718 ; 816 , 818 ) are provided on at least one of the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ). 13. Implant according to one of claims 4 to 12, characterized in that the transverse web ( 674 ; 774 ; 874 ) and/or at least one of the two legs ( 672 , 673 ; 772 , 773 ; 872 , 873 ) have a substantially rectangular cross-section. 14. Implant according to one of the preceding claims, characterized in that the implant ( 600 ; 700 ; 800 ) comprises a tool holder ( 682 , 683 ; 782 , 783 ; 882 , 883 ) for connection to an insertion tool. 15. Implant according to claim 14 and one of claims 4 to 13, characterized in that the tool holder ( 682 , 683 ; 782 , 783 ; 882 , 883 ) is arranged on the clamp ( 670 ; 770 ; 870 ). 16. Implant according to one of claims 14 or 15, characterized in that the tool holder comprises at least one angled projection ( 682 , 683 ; 782 , 783 ; 882 , 883 ) pointing away from the implant ( 600 ; 700 ; 800 ). 17. Implant according to one of the preceding claims, characterized in that the first and the second surface ( 458 , 459 ; 558 , 559 , 858, 859 ) of the at least one fixing element ( 430 ; 530 ; 885 ) in contact with at least one facet ( 416 , 418 ; 516 , 518 ; 816 , 818 ) are concavely curved in the direction of the associated facet surface. 18. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 566 , 567 ; 666 , 667 ; 785 ) comprises a plane-parallel plate. 19. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 130 ; 230 ; 330 ) has a wedge shape. 20. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 130 ; 230 ; 330 ) is conical or multiply conical. 21. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 130 ; 230 ; 430 ; 530 ; 885 ) has a curvature adapted to at least one of the two facets ( 118 ; 218 ; 416 , 418 ; 516 , 518 ; 816 , 818 ). 22. Implant according to one of the preceding claims, characterized in that anchoring elements ( 352 , 353 ; 566 , 567 ; 672 , 673; 772 , 773 ; 872 , 873 ) projecting in the direction of the facets are provided on the implant ( 300 ; 500 ; 600 ; 700 ; 800 ). 23. Implant according to claim 22, characterized in that the anchoring elements are designed in the form of cutting edges ( 672 , 673 ; 772 , 773 ; 872 , 873 ), teeth ( 352 , 353 ) or ribs ( 566 , 567 ). 24. Implant according to claim 23, characterized in that the at least one fixing element ( 130 ; 530 ) carries two ribs ( 140 , 141 ; 566 , 567 ) projecting laterally substantially transversely to a plane defined by the at least one fixing element ( 130 ; 530 ). 25. Implant according to one of the preceding claims, characterized in that the at least one fixing element ( 130 ; 230 ; 430 ) is provided with openings ( 132 ; 232 , 233 ; 464 ). 26. Implant according to one of the preceding claims, characterized in that at least one fastening element receptacle ( 132 ; 232 , 233 ; 464 ) is provided on the implant ( 100 ; 200 ; 400 ). 27. Implant according to one of the preceding claims, characterized in that at least one stabilization stop (140, 141 ; 250 ; 350 ; 566 , 567 ; 674 ; 774 ; 874 ) for stabilizing the fixing element ( 130 ; 230 ; 330 ; 530 ; 666 , 667 ; 785; 885 ) is provided on the implant ( 100 ; 200 ; 300 ; 500 ; 600 ; 700 ; 800 ) in the joint space . 28. Implant according to claim 27, characterized in that the stabilization stop comprises two projections ( 140 , 141 ) arranged on end faces ( 136 , 137 ) of the fixing element ( 130 ) and projecting in the same direction. 29. Implant according to one of the preceding claims, characterized in that the implant ( 100 ; 200 ; 300 ; 400 ; 500 ; 600 ; 700 ; 800 ) is formed in one piece. 30. Implant according to one of the preceding claims, characterized in that the implant ( 100 ; 200 ; 300 ; 400 ; 500 ; 600 ; 700 ; 800 ) has a surface provided with a microstructure and/or a bioactive coating. 31. Implant according to one of the preceding claims, characterized in that the implant ( 100 ; 200 ; 300 ; 400 ; 500 ; 600 ; 700 ; 800 ) is made of a radiolucent material. 32. Implant according to one of the preceding claims, characterized in that the implant ( 100 ; 200 ; 300 ; 400 ; 500 ; 600 ; 700 ; 800 ) is made of TiAl6V4 or NiTiNol.