DE10035182A1 - Instrument for inserting intervertebral implant has stop on forward thrust element, with protuberance, cavity , guide track with two arms - Google Patents

Abstract

The forward thrust element supported on the track for the intervertebral implant (2) has a stop when the implant has reached its required end position in the space bounded by two adjacent vertebrae. The distal end of the forward thrust element has a protruding part into a cavity (22) in the implant. The guide track has two parallel arms which fit into lengthwise grooves (22-24) open on the underside or top side.

Description

The invention relates to an insertion instrument for a Intervertebral implant with one between two adj beard swirl usable guideway for the Zwi intervertebral implant and the intervertebral implant advancing along the guideway feed element supporting the guideway.

Such an insertion instrument is, for example, from the German utility model 299 16 079 known.

The invention has for its object a setting instrument of the type described at the beginning improve that the insertion process of the intervertebral implant is further facilitated.

This task is the one with an insertion instrument type described above solved according to the invention that a stop is provided on the feed element, which changes when the desired end position of the Intervertebral implant in the intervertebral space of two adjacent vertebral bodies to one vertebral body applies, and that the feed element relative to the Füh train even after the attack on a we the body can be advanced further.

In this way, the feed element is based on Advancing the intervertebral implant into the Zwi vertebral space on a vertebral body as soon as the  Desired immersion depth of the intervertebral implant reached in the intervertebral space. Another one Pushing the feed element towards the Intervertebral space is excluded by that the stop acts as an immersion depth limit Zung.

If the feed element knows relative to the guideway ter forward, that is, in the distal direction, ver is pushed, this must therefore lead to the fact that the trajectory relative to that striking the vertebral body and thereby held feed element in the is moved in the opposite direction, i.e. in proximal direction, that is the guideway pulled out of the intervertebral space. Ver the intervertebral implant remains inside the Zwi vertebral space while the insertion instrument is removed from the intervertebral space. You get thus by advancing the feed element relatively first push the intermediate to the guideway vertebral implants up to the desired end position in the Intervertebral space and then without changing the feed process itself a removal of the insertion instrument of the intervertebral implant used and an ent removal of the insertion instrument from the intervertebral vertebra room. The operator therefore does not have to do this during the insertion process carry out different handling steps, son a single handling step, namely the front push the feed element relative to the guide bahn, inevitably leads to the described result sen.  

It is advantageous if the feed element is in a guide tion slidable in the direction of the guideway device, which in turn is arranged on the guideway is.

It is particularly advantageous if the feed element is designed as a rack that with one on the Guide track mounted, rotatable gear meshes.

The feed element can preferably at its dista len end be graduated and with a front jumping part into a recess of the intervertebral vertebra Immerse the implants while a recoil Part of a contact surface for the intervertebral implant formed. So that the feed element against a lateral displacement relative to the intervertebral limb Plantat secured, but can easily in advance direction of thrust deducted from the intervertebral implant become.

The stop on the feed element can for example be formed by a transversely projecting pin.

In a particularly preferred embodiment provided that the guideway two essentially has parallel arms that the Guide the intervertebral implant between them.

It is advantageous if the mutual distance the arms are changeable so that the arms at the same time  serve as a spreading device, which when the mutual distance in their distal, in the Zwi the vertebral body separate from each other and thus the intervertebral space expand.

In particular, the arms can be at their proximal end about an axis transverse to its longitudinal direction be pivotally connected.

It is beneficial if the distance between the arms is at the distal End is less than at the proximal end, this will it allows that only by advancing the Intervertebral implant swings apart Arms and thereby spreading in the distal end area the poor is reached.

In a preferred embodiment, that the arms in to the top or to the Un open longitudinal grooves of the intervertebral limb Immerse plantates. To guide the intervertebral limb It is therefore sufficient for plantates to face each other open longitudinal grooves are provided on the sides, that take up the arms.

It is beneficial if the arms are up protruding from the longitudinal grooves below, ins especially if the arms are up or down only in the distal part of the intervertebral implant protrude the longitudinal grooves.  

Such an arrangement leads to the fact that Intervertebral body when inserting the intervertebral Support belimplantates on the arms that come from the Emerge longitudinal grooves of the intervertebral implant, so that the intervertebral implant easily along the arm can be advanced without having to move the neighboring beard vertebral bodies come into contact. Not until Pull the arms out of the longitudinal grooves and out in the intervertebral space the neighboring ones sink Vertebral body on the inserted intervertebral implant dismissed and then rest on this.

It can be provided that one arm two next to mutually arranged webs, preferably the other arm the space between the two Is opposite.

The webs can also each be in an open Immerse the longitudinal groove of the intervertebral implant, at such a construction are thus on one side of the intervertebral implant two at a distance from each other the arranged longitudinal grooves arranged on the against overlying side however only one that is preferred between the two longitudinal grooves on the opposite the side.

It is advantageous if the guide makes a stop carries the one when resting on a vertebral body immersion depth of the guideway in the intervertebral space limited. This also makes insertion easier, since the Operator inserting the insertion instrument into  the intervertebral space this up to a defined one Can advance immersion depth.

It is favorable if the feed element is connected bears with which one against the Ver slide-resistant connection to the intermediate wire bel implant is producible. Such a connection enables the feed element and the intermediate wire Belimplantat to connect so that with the feed ment the intervertebral implant from the interwir can be pulled out. This becomes the before retracted thrust element opposite the guideway, this then supports itself with its attack on a we the body and pulls the feed element right relative to the vertebral body and thus relative to the Zwi vortex space back, that with the feed element tensile intervertebral implant is on taken this way. The insertion tool about takes on the function of an extractor in this case mentes.

In a further preferred embodiment is before seen that the stop on the feed element in the Movement direction fixed in different positions can be laid. This allows the insertion depth of the intermediate vertebral implant in the intervertebral space varies become.

For example, the feed element can be moved Several insertion openings offset from one another  for the stop, in which this is optional is used.

In another embodiment it is provided that ver on the feed element in the direction of displacement slidably a stop body carrying the stop ge is stored in different positions is.

In particular, the stop body can be locked be fixable, which can be detached in teeth of as a rack trained feed element engages.

The following description of preferred embodiment forms of the invention is used in connection with the Drawing of the detailed explanation. Show it:

Figure 1 is a side view of an intervertebral implant with three longitudinal grooves for guiding the arms of an insertion instrument in the direction of the longitudinal grooves.

Fig. 2 is a view similar to Figure 1 transverse to the direction of the longitudinal grooves.

Company 3 is a top view of the implant of FIGS. 1 and 2;

Fig. 4 is a perspective view of the implant gate of Figures 1 to 3.

Fig. 5 is a view of the implant of Figures 1 to 4 with an attached before thrust element of an insertion instrument not otherwise shown;

Fig. 6 is a view of the complete insertion instrument for the intervertebral implant did the body of Figures 1 to 4 before inserting the intervertebral implant into the intervertebral space between two vertebrae;

FIG. 7 is a view of the insertion instrument in FIG. 6 in the direction of arrow A in FIG. 6;

FIG. 8 is a side view of the insertion instrument of FIG. 6 after the intervertebral implant has been inserted into the intervertebral space;

Fig. 9 is an enlarged detail view of the area B in Fig. 8;

Fig. 10 is a view similar to FIG. 8 with element advanced against the guideway of the inserting element and after pulling out the guideway of the inserting instrument from the intervertebral space of the adjacent vertebral body and

Fig. 11 is a perspective view of an in plantates and the front part of a feed element with a longitudinally displaceable before the feed element thrust body.

The Einsetzinstru to 10 shown in FIGS. 6 element 1 serves for inserting a Zwischenwirbelimplan tates 2 be in the intervertebral space 3 between two adjacent vertebral bodies 4, as shown in FIGS. 1 to 4.

The insertion instrument 1 comprises a first arm 5 with two parallel, spaced-apart, rod-shaped webs 6 , 7 which are connected to one another at their proximal end by a bridge 8 and which both have a rectangular cross section.

The bridge 8 protrudes perpendicularly from the plane spanned by the two webs 6 and 7 and forms a pivot bearing 9 for a second arm 10 which , in a manner similar to the webs 6 and 7, has a rectangular cross section and the same length. The pivot axis 11 of the arm 10 extends transversely to the longitudinal direction of the arm 10 and is arranged at a distance from the plane spanned by the webs 6 and 7 , the space between the webs 6 and 7 is larger than the width of the second arm 20th As a result, the distal end of the second arm 10 can dip into the space between the two webs 6 and 7 .

In the area between the webs 6 and 7, on the one hand, and the pivot bearing 9 for the second arm 10, on the other hand, a guide sleeve 12 is held on the bridge 8 , in which a rod-shaped feed element 13 is mounted in a longitudinally displaceable manner, the direction of displacement running parallel to the longitudinal extension of the webs 6 and 7 . In its proximal part, the feed element 13 is designed as a toothed rack 14 , with which a toothed wheel 15 meshes, which is rotatably mounted on the bridge 8 about an axis of rotation which runs parallel to the pivot axis 11 . The gear 15 is connected to a handle 16 , through which the gear 15 can be rotated. During this rotation, the feed element 13 is displaced in the guide sleeve 12 .

Both on the webs 6 and 7 and on the arm 10 are arranged at a certain distance from their distal end outwardly projecting pins 17 , 18 which form the stops for the vertebral bodies 4 when the insertion instrument 1 with the distal end portions of the webs 6 and 7 and the arm 10 is inserted into the intervertebral space 3 ( Fig. 6), so that an immersion depth limitation is carried out by these stops.

The 1 to 4 shown in Fig. Zwischenwir Belimplantat 2 has essentially the shape of a fla chen ring with an upper support surface 19 and a lower support surface 20 , which are each provided with pointed projections 21 . In this ring body of the intervertebral implant 2 is a central, incorporated upwardly open longitudinal groove 22, also befin the parallel in this ring body has two to the longitudinal groove 22 extending, downwardly open, to both sides of the longitudinal groove 22 disposed more longitudinal grooves 23 and 24th

The width of these longitudinal grooves 22 , 23 and 24 corresponds to the width of the arm 10 or the webs 6 , 7 , the depth of the longitudinal grooves 22 , 23 and 24 is designed so that the webs or the arm at least partially protrude from the longitudinal groove, when the webs and the arm lie against the bottom of the longitudinal grooves.

In the embodiment shown in the drawing, the support surfaces 19 and 20 are slightly inclined towards each other, so that the distance between the support surfaces 19 and 20 at the distal end of the implant is less than at the proximal end ( FIG. 2), so that the depth of the longitudinal grooves 22 , 23 and 24 is larger at the proximal end than at the distal end. This can lead to the fact that the webs 6 , 7 and the arm 10 only protrude from the longitudinal grooves at the distal end, but not at the proximal end.

To insert the intervertebral implant 2 into an intervertebral space 3 , the second arm 10 is first pivoted away from the webs 6 and 7 in such a way that they are freely accessible from above. The intervertebral implant 2 is placed on the webs 6 and 7 so that they dip into the longitudinal grooves 23 and 24 , in a region which lies between the proximal end of the insertion instrument 1 and the distal end ( Fig. 6).

Then the second arm 10 is pivoted against the webs 6 and 7 that it dips into the longitudinal groove 22 . The intervertebral implant 2 is thereby between the webs 6 , 7 on the one hand and the arm 10 on the other hand leads in the longitudinal direction on the insertion instrument 1 , the webs 6 and 7 together with the arm 10 form a guideway for the intervertebral implant 2 .

The insertion instrument is then inserted with the distal ends of the webs 6 and 7 and the arm 10 in the inter mediate vertebral space 3 until the pins 17 , 18 rest against the vertebral bodies 4 , as is evident, for example, from FIG. 6.

By means of the handle 16 , the feed element 13 is displaced in the distal direction until the distal end of the feed element 13 lies against the intervertebral implant 2 . The distal end of the thrust element 13 can be designed in stages so that a projecting part dips into the longitudinal groove 22 , while the recessed part rests against the outside of the intervertebral implant 2 . As a result, the thrust element 13 is fixed in the transverse direction relative to the intervertebral implant 2 .

By further turning the gear 15 via the handle 16 , the feed element 13 can be advanced in the distal direction and thereby pushes the intervertebral implant 2 also in the distal direction along the webs 6 , 7 and the arm 10 in the direction of the intervertebral space 3 . This leads to a Ver pivoting of the arm 10 relative to the webs 6 and 7 , so that the distance between the webs 6 , 7 on the one hand and the arm 10 on the other hand is enlarged ver in the distal end region, thereby the vertebral bodies 4 are removed from each other, the the intervertebral space 3 is widened. The insertion instrument thus acts as a spreading instrument by advancing the intervertebral implant 2 in the distal direction.

The advancing movement of the intervertebral implant 2 is continued until it is advanced into the desired position in the intervertebral space 3 .

When this desired position is reached, a stop in the form of a pin 25 projecting from the feed element 13 rests against the vertebral body 4 and prevents the feed element 13 from being able to be advanced further relative to the vertebral body 4 ( FIGS. 8 and 9). The feed movement of the intervertebral implant 2 is limited, that is, it is ensured that the intervertebral implant 2 reaches exactly the desired insertion depth.

With further rotation of the gear 15 by means of the handle 16 in the same direction, the feed element 13 is advanced further in the distal direction relative to the rest of the insertion instrument 1 , but is supported by the pin 25 on the vertebral body 4 , so that the relative movement between the feed element 13 is on the one hand and the ge from the webs 6 , 7 and the arm 10 formed other insertion instrument 1 on the other hand leads to the fact that this remaining insertion instrument 1 is removed in the proximal direction from the vertebral body 4 , that is, the distal end portions of the webs 6 and 7 and the arm 10 pulled out of the longitudinal grooves 22 , 23 and 24 and thus out of the intervertebral space 3 . The adjacent vertebrae 4 sit on the support surfaces 19 and 20 .

As soon as the distal end sections of the webs 6 and 7 as well as the arm 10 are pulled out of the intervertebral space 3 ( FIG. 10), the insertion instrument 1 can be removed in the proximal direction, the intervertebral implant 2 then remains between the two vertebrae 4 in the desired position.

In the exemplary embodiments in FIGS. 5 to 10, the stop with which the feed element 13 bears against a vertebral body 4 is formed by a fixed pin 25 . This can be screwed into the feed element, for example.

In a preferred embodiment, it is possible to fix this pin 25 in the feed direction in various positions on the feed element 13 , for example in that a larger number of screw holes are provided for the pin 25 . As a result, the insertion depth for the intervertebral implant can be varied.

In Fig. 11, a further preferred embodiment of a feed element 13 is shown, in which the stop is not formed by a pin, but son by a stop body 26 , the feed element 13 sleeve-shaped surrounding this is longitudinally displaceably mounted and its distal, the Intermediate vertebra implant face 27 forms a stop limiting the immersion depth. At the impact body 26 carries a detent 28 which engages in the teeth of the rack 14 and thus sets the stop body by 26 in the direction of displacement on the feed element 13 in the desired position. The detent 28 can be solved by actuation means 29 shown only schematically in the drawing so that the stop body 26 is moved along the feed element 13 to a different position, in which it is then fixed by engaging the detent 28 in the rack 14 again becomes.

At the feed element 13 attachment means may be provided at its distal end, which ermögli chen, the feed element 13 and the Zwischenwirbelim Plantat 2 tensile strength with each other to be connected, so that when the retraction of the feed element 13, the intervertebral implant 2 pull-out from the intervertebral space 3 force to the Intervertebral implant 2 can be transferred.

The insertion instrument described can also be used as a pull-out instrument in such a configuration. If namely the feed element 13 in the manner described be tensile to the intervertebral implant did 2 and if the feed element 13 is retracted relative to the arm 5 , then the arm 5 is supported by the pins 17 , 18 on the Wirbelkör 4 and allows so the application of a pull force on the intervertebral implant 2 , through which this is pulled out of the intervertebral space 3 who can.

Claims (21)

1.Inserting instrument for an intervertebral implant with an insertable guideway for the intervertebral implant between two adjacent vertebrae and with an advancing element which moves the intervertebral implant along the guideway and is supported on the guideway, characterized in that a stop ( 13 ) on the feed element 25 ; 26 , 27 ) is provided, which when reaching the desired end position of the intervertebral implant ( 2 ) in the inter median vertebral space ( 3 ) of two adjacent vertebral bodies ( 4 ) bears against a vertebral body ( 4 ), and that the feed element ( 13 ) relative to the guide track ( 5 , 10 ) even after the stop ( 25 ; 26 , 27 ) on a vertebral body ( 4 ) can be advanced. 2. Instrument according to claim 1, characterized in that the feed element ( 13 ) with a Füh tion ( 12 ) in the direction of the guideway ( 5 , 10 ) is slidably mounted, which in turn is arranged on the guideway. 3. Instrument according to claim 1 or 2, characterized in that the feed element ( 13 ) is designed as a rack ( 14 ) which meshes with a rotatable gear ( 15 ) mounted on the guide track ( 5 , 10 ). 4. Instrument according to one of the preceding Ansprü surface, characterized in that the feed element ( 13 ) at its distal end is stepped out and with a projecting part in a recess ( 22 ) of the intervertebral implant ( 2 ), while a recessed part forms a contact surface for the intervertebral implant ( 2 ). 5. Instrument according to one of the preceding and workman surface, characterized in that the stop ( 25 ) is formed by a pin projecting transversely from the feed element ( 13 ). 6. Instrument according to one of the preceding and workman surface, characterized in that the guideway has two substantially parallel to each other duri fende arms ( 5 , 10 ) which guide the intervertebral implant ( 2 ) between them. 7. Instrument according to claim 6, characterized in that the mutual distance between the arms ( 5 , 10 ) is variable. 8. Instrument according to claim 7, characterized in that the arms ( 5 , 10 ) at their proximal end de to a transverse to their longitudinal direction de axis ( 11 ) are pivotally connected. 9. Instrument according to one of claims 7 or 8, characterized in that the distance between the arms ( 5 , 10 ) at the distal end is less than at the proximal end. 10. Instrument according to one of claims 6 to 9, characterized in that the arms ( 5 , 10 ) in the top or bottom of open longitudinal grooves ( 22 , 23 , 24 ) of the intervertebral implant ( 2 ) immerse. 11. Instrument according to claim 10, characterized in that the arms ( 5 , 10 ) project upwards or downwards from the longitudinal grooves ( 22 , 23 , 24 ) forth. 12. Instrument according to claim 11, characterized in that the arms ( 5 , 10 ) upward or downward only in the distal part of the intervertebral implant ( 2 ) protrude from the longitudinal grooves ( 22 , 23 , 24 ). 13. Instrument according to one of claims 6 to 12, characterized in that the one arm ( 5 ) comprises two webs ( 6 , 7 ) arranged next to one another. 14. Instrument according to claim 13, characterized in that the other arm ( 10 ) opposite the space between the two webs ( 6 , 7 ). 15. Instrument according to claim 14, characterized in that the webs ( 6 , 7 ) each immerse in an open longitudinal groove ( 23 , 24 ) of the intervertebral implant. 16. Instrument according to one of the preceding claims, characterized in that the guide track ( 5 , 10 ) carries a stop ( 17 , 18 ) which, when in contact with a vertebral body ( 4 ), the immersion depth of the guide track ( 5 , 10 ) limited the intervertebral space ( 3 ). 17. Instrument according to claim 16, characterized in that the feed element ( 13 ) carries Verbindungsmit tel, with which a against the direction of advance pull-resistant connection to the inter mediate vertebra implant ( 2 ) can be produced. 18. Instrument according to one of the preceding claims, characterized in that the stop ( 25 ; 26 , 27 ) on the feed element ( 13 ) can be fixed in its displacement direction in a different position. 19. Instrument according to claim 18, characterized in that the feed element ( 13 ) in the displacement direction offset from one another has a set of openings for the stop ( 25 ). 20. Instrument according to claim 18, characterized in that on the feed element ( 13 ) slidably in the direction of advance a stop ( 27 ) bearing stop body ( 26 ) is mounted, which can be fixed in different positions. 21. Instrument according to claim 20, characterized in that the stop body ( 26 ) by a catch ( 28 ) can be fixed, which releasably engages in teeth of the rack ( 14 ) formed feed element ( 13 ).