DE202005021705U1 - Device for producing spinal implants - Google Patents

Abstract

Device for producing spinal implants according to a method, in which bone cement or a similar material (17) in the liquid or pasty state is introduced into a hollow mold (10, 10 ', 20), in which the hollow mold (10, 10', 20) is adapted to the individual anatomical conditions, in which the material (17) in the hollow mold (10, 10 ', 20) cures to form the implant and in which subsequently the cured implant for surgical implantation is removed, characterized by a Mold (10, 10 ', 20) consisting of one or more parts that allow in their interaction the impression of the three-dimensional implant.

Description

The The invention relates to a device for producing spinal implants.

Known are spinal implants, which with the help of preformed tools from a liquid or pasty Material such as bone cement or another plastic can be shaped. As a liquid Plastic, for example, acrylate bone cement, which, for example also sold under the trade name Pallacos used become.

at These implants are essentially about 1.5 cm big Disc, which also ring-shaped is formed, and which, for example, instead of an intervertebral disc in the spine be introduced. Such implants are also referred to as cages.

So far Comparable implants are industrially manufactured and in different Sizes for the operation maintained. The surgeon chooses make the most suitable implant and implant it. adversely It is that, as a rule, the implants are not exactly on the adapted to individual circumstances of the corresponding patient are.

alternative can the pasty Material introduced directly into the intervertebral space, where appropriate shaped according to the individual operational circumstances hardened become. To make this technique with plastic cements implants, in particular implants for the replacement of the cervical intervertebral discs but the disadvantage that the plastic cures in the body of the patient. This leads to one that non - setting monomers of most plastic glue in the body remain there and can trigger bio logical reactions. This is special for polyacrylate cements known whose monomers are potentially toxic. Furthermore arise For many of the plastic cements when curing temperatures in the range of 70 ° C, which can lead to necrosis of the immediately adjacent tissue. This can result in the consequence that the implant due to the destroyed cellular structure in the neighborhood in the bone body sinks in or loosens. In the area of the spine goes from the bone cement, Depending on the chemical composition due to the great heat also a danger for the spinal cord made expensive by constant cooling must be prevented.

Farther free-formed bone cement implants have the disadvantage that Although they are individually formed, but they are not necessarily one optimal stability reach because unwanted Formations, for example, in a narrow situs or dorsal of the Implants are difficult to control. Another disadvantage is that undesirable Penetration of the plastic material in the soft state in the adjacent Bone.

One Another disadvantage of the free-formed implants is that they have no central cavity within which a bony fusion can take place. The merger thus arises only outside of the implant, which is why the external loads one under certain circumstances counteracts lower bone mass.

Finally does the implantation of bone cement usually in particular The spine additionally the use of other foreign materials, such. B. collagen sponge necessary to dura mater and spinal cord before the touch with the liquid or pasty Protect plastic. This causes costs and increases the foreign material entry.

Of the general advantage of plastic cements over the industrially prefabricated However, Cages is based on that the adjustment be made intraoperatively individually can and that plastic cements are much cheaper than prefabricated Implants. This is one of the reasons that the use of Plastic cements, for example, always on the cervical spine still the predominant one Part of the cervical spine implants in Germany.

Therefore The object of the invention is to provide a device for manufacturing of spinal implants provide in which the implants individually to the respective Circumstances can be adjusted, the dangers of damage However, be avoided by surrounding tissues and adjacent vertebral bodies.

The Task is solved by a device for producing spinal implants with the features of claim 1 or 2.

advantageous Embodiments and developments of the invention are specified in the subclaims.

The inventive method for making spinal implants has the following steps. First will be bone cement or a similar one Material in liquid or pasty Condition introduced into a mold. This mold is then during the Operation adapted to the individual anatomical conditions. Finally will the bone cement cured, causing the implant is formed. The finished implant can then be removed taken from the mold and implanted surgically.

The inventive method thus provides, while the surgery individually for to produce implants for patients with the aid of suitable tools which after curing of the material are implanted.

Of the Advantage of the invention over the technology Introducing the liquid or pasty Material is directly in the intervertebral space is that the Risks due to the rather random Shaping, the release of heat energy and the release of chemical Materials are bypassed to the surrounding tissue. It is created on the Patient needs adapted but nevertheless made with high precision Implants. A direct contact between the reactible material components and the patient is avoided. This is a high security against unwanted Deformation, cavitation, chemical and thermal reactions guaranteed when dealing with plastic cements. Continue allowed this method, compared with the hand molding of implants, a precise one and reproducible and thus the security increasing production of individual Implants.

The inventive device for making spinal implants is formed as a shape consisting of one or more parts, in their interaction the impression of the three-dimensional Enable implants.

there In essence, two different types of shapes are used. Both forms serve to make the pasty or liquid material outside of the body curing the patient, to avoid the patient's thermal and chemical stress however the forms during the operation for to be able to adapt to the respective patient.

In In a first alternative, this is one or more parts rigidly formed, which bil bil den, in its interior a cavity is formed for the impression of the implant.

During the Operation can be done as soon as the damaged Intervertebral disc removed and the size of the intervertebral space it is evident that for These operational conditions suitable form individually for each Patients selected and the corresponding implant made on site and adapted become. The curing of the implant material takes place outside of the body, thereby prevents the thermal and chemical stress of the patient become.

Preferably is an injection port in the mold arranged. Thus, the mold can be made even after assembly their individual parts from the outside with the liquid or pasty Material filled become.

advantageously, are the individual parts of the mold through a mechanical connection, preferably connected by joints and / or self-locking closures. This ensures that the individual parts of the mold each in a fixed position relative can be assembled together. In addition, after filling the mold with the liquid or pasty Material and after curing of the material, the mold can be easily reopened to the implant to be able to remove.

at an advantageous embodiment of the invention hold the mechanical Connect the individual parts of the form together form-fitting. This will ensure that when filling the shape of the material is not due to bad contacts between the can penetrate individual parts.

at a particularly preferred embodiment According to the invention, the mold consists of two parts, preferably one Bottom part and a lid part. A shape of two parts can be especially easy to assemble and open. It is preferable to be there the two parts over a mechanical connection connected in the manner of a hinge.

at An advantageous embodiment of the invention is in the housing elastic insert consisting of one or more parts, to be able to form negative angles in the implant, however nevertheless after curing of the Material to be able to detach the implant from the mold.

Preferably are in the region of the contact zones of the individual parts of the elastic Use of the form beads or lips arranged when assembling the individual parts interlock and avoid burrs on the outside serve the implant.

advantageously, the mold has an opening for receiving an insertion tool, which preferably in Area of the contact zone between the bottom and top part of the tool arranged is. The insertion tool serves to grip the implant and to be able to implant without to touch it with other instruments, possibly damaging it could.

Advantageously, the insertion tool is designed in the manner of a screw or a threaded rod. This configuration of the insertion tool ensures that the insertion tool after removal of the implant the mold and insertion into the intervertebral space can be unscrewed from the cured implant without damaging the implant.

Preferably is the mold with movable pins and / or slides for molding of holes and recesses, in particular for inserting the insertion tools, equipped in the implants, which after curing of the Material can be pulled out or-rotated.

at a particularly preferred embodiment The invention allows the mold to mold several implants simultaneously. This has the advantage of having implants at the same time in different sizes and Shapes can be made.

at A preferred embodiment of the invention is the height of the mold variable, preferably by an interposed element, preferably an element in the form of a metal plate. This is guaranteed that the shape during of surgery according to individual circumstances The patient can be adjusted to different implants Height to produce can.

A particularly advantageous embodiment of the invention is the inside of the mold has a surface coating. This ensures that the cured material does not interfere with the Glued tool.

at an advantageous embodiment According to the invention, the cavity formed in the mold at least a Durchbauungsbereich on. Within such a breakdown area can a bony one Fusion, which ensures increased stability becomes.

Preferably For example, the mold has a port for evacuating the mold. A Evacuation of the mold before filling the liquid or pasty material guaranteed that the material is distributed throughout the mold and no air bubbles arise.

advantageously, is in the injection opening sleeve insert arranged. Through the sleeve insert the material is injected into the mold, whereby the sleeve with Material filled becomes. After curing becomes the sleeve insert turned off and thus the spray nose removed from the implant ent, so that a smooth outside of the implant is guaranteed. At the same time, the tool is freed of superfluous sprayed material.

Preferably has the shape of valve-like openings on, which preferably open, once a certain level of overpressure within the form is reached. These allow leakage of the excess material.

In In a second alternative, the mold is formed from an elastic sheath. In this is the liquid or pasty Material filled, subsequently the stuffed elastic shell used in the intervertebral space and relax the vertebrae so far be like the later relative position of the vertebrae corresponds to each other, so that the envelope exactly adapted to the individual circumstances of the respective patient becomes. In particular, the use of an elastic sheath also allows the Production of negative angles or undercuts. The shell will but only in the intervertebral space until the material as far as cured is that no more shape changes occur. Then the elastic shell is again from the intervertebral space removed, leaving the bulk the curing process again outside of the body takes place to the thermal and chemical load of the patient to prevent. Subsequently can the elastic shell from cured Implant demolished and the implant implanted.

Preferably is the elastic shell made of polyethylene or silicone. This allows a special Easier release of the implant from the tool.

Preferably has the elastic shell an injection port so that the shell with the liquid or pasty Material filled become.

advantageously, the elastic sheath has an opening for an insertion tool on, wherein the insertion tool preferably in the manner of a screw or a threaded rod is formed. The insertion tool is used to be able to touch and implant the implant without to touch it with other instruments, possibly damaging it could. By this configuration of the insertion as a screw or Threaded rod is guaranteed that the insertion tool after removing the implant from unscrewed from the cured implant in the form and insertion into the intervertebral space can be done without damaging the implant.

at an advantageous embodiment of the invention, the inside the elastic shell one surface coating on to the elastic shell after curing of the material remove residue-free to be able to.

Preferably, the elastic sheath on at least one Durchbauungsbereich to a to ensure bony fusion of the adjacent vertebral bodies.

advantageously, is the elastic shell essentially annular, U-shaped or H-shaped, resulting in different construction areas, either centrally or laterally, train.

Preferably has the elastic shell a port for evacuation to the hull before filling with the liquid or pasty To evacuate material, around air pockets to prevent.

at a particularly preferred embodiment the invention has the elastic sheath stabilizing elements on. These prevent the short-term onset of liquid or pasty Material filled Shell in the intervertebral space and when relaxing the adjacent vertebrae a undesirable Deformation of the shell and ensure certain minimum dimensions of the implant to be produced. To has the elastic shell preferably at least one extending from anterior to posterior Having stabilizing element.

advantageously, the stabilizing elements are arranged in tabs around a Contact of the stabilizing elements with the liquid or pasty material and thus a "ingrowth" of the stabilizing Elements in the implant to prevent and continue a substantially smooth outside of the implant.

at a preferred embodiment the invention has the elastic sheath on its cranial and / or caudal side formed by substantially rigid material Areas in which structuring are formed. These Structuring serves to place the implant in the adjacent To fix vertebrae and prevent slipping of the implant. For this, the structures are preferably in the manner of cones, Pyramids, teeth, spikes, Keels, fins or pimples trained.

Preferably has the elastic shell channels for receiving metallic elements which serve, channels or Create notches in the implant in which insertion instruments can be attached.

at a particularly preferred embodiment the invention, the elastic sheath valve-like openings on, that open, once a certain level of overpressure inside the elastic shell is reached. This ensures that that excess liquid or pasty Material can escape.

Preferably is the interior of the elastic shell over the valve-like openings with reservoirs for receiving the excess bone cement or similar Material connected to specifically collect the material and in particular while the phase of insertion of the liquid or pasty material filled elastic shell in the intervertebral space, a leakage of the material into the intervertebral space and prevent adjacent tissues. These are the reservoirs preferably on the outside the elastic shell or are arranged in one of the breakdown areas.

at a preferred embodiment the invention is arranged in one of the Durchdurchungsungsbereiche Reservoir through an outer shell, one arranged in the outer shell metallic, two-piece case and one disposed in the metallic shell inner shell formed, wherein the inner shell over the valve-like openings with the elastic shell connected is. this makes possible a catching of the exiting material and a removal of the Reservoirs also within the construction area.

Around the elastic shell after curing to remove the material, is the elastic shell advantageously along at least one predetermined breaking line rupture. Preferably is the at least one predetermined breaking line through a material weakening, a Perforation or a material reinforcement formed to allow a targeted rupture of the elastic sheath.

at A preferred embodiment of the invention is the at least one Rupture line formed from anterior to posterior running.

Preferably is the elastic shell is formed double-layered. This offers an additional one Safety when inserting the with the liquid or pasty material filled elastic shell in the intervertebral space, allows but also a tearing up and down the sleeve from the cured one Implant also in the inserted state in the intervertebral space.

In a particularly preferred embodiment of the invention, the elastic sheath is formed from at least two tearing tabs connected by predetermined rupture lines extending from the anterior side to the posterior side, which are guided from the anterior side to the posterior side and returned to the anterior side after attachment to the posterior side. This allows a tearing and tearing of the elastic sheath of the cured material even in the case that the filled with the liquid or pasty material shell was inserted into the disc space and according to Re lax the vertebra could not be removed.

at an advantageous embodiment of the invention, the elastic Shell at least a vertically extending shock absorber in order to relax the vortex a certain minimum height to ensure the implant to be produced. Preferably is through to the shock absorber one in a tubular one Sleeve axially movable plunger formed, the movement of the plunger in the sleeve is damped by friction and / or by a spring element arranged in the sleeve.

The Invention is illustrated by the in the following figures embodiments in detail explained. It shows:

1a Top view of an embodiment of a device for producing spinal implants consisting of two parts in the unfolded state,

1b Side view of the embodiment according to 1 in the folded state,

1c Top view of a further embodiment of an apparatus for simultaneously producing a plurality of spinal implants consisting of two parts in the unfolded state,

2a a perspective view of an embodiment of an apparatus for producing spinal implants with an elastic sheath and a Durchbauungsbereich,

2 B a perspective view of another embodiment of an apparatus for producing spinal implants with an elastic sheath and two expansion areas,

2c a perspective view of another embodiment of an apparatus for producing spinal implants with an elastic sheath and two expansion areas,

2d a perspective view of another embodiment of an apparatus for producing spinal implants with an elastic sheath and several Durchbauungsbereichen,

2e a perspective view of another embodiment of an apparatus for producing spinal implants with an elastic sheath, which is U-shaped,

2f a perspective view of another embodiment of an apparatus for producing spinal implants with an elastic sheath, which is H-shaped,

3a a plan view of the anterior side of another embodiment,

3b a plan view of the anterior side of another embodiment,

3c a side view of the embodiment according to 3c .

4a a sectional view through an embodiment with stabilizing elements,

4b a sectional view through a further embodiment with stabilizing elements,

4c a side view of another embodiment with stabilizing elements,

5a a sectional view of an embodiment with valve-like openings,

5b a sectional view of another embodiment with valve-like openings,

6a a side view of an embodiment with a plurality of predetermined breaking lines,

6b a plan view of the posterior side of the embodiment according to 6a .

6c a plan view of the anterior side of another embodiment with a plurality of predetermined breaking lines and tear tabs,

7 a sectional view of an embodiment with a screw as Einsetzinstrument,

8th a sectional view of an embodiment with shock absorbers,

9a a perspective view of an embodiment with structures of the cranial and caudal side,

9b a side view of another embodiment with structures of the crani alen and caudalen side and

9c a side view of another embodiment with structures of the cranial and caudal side.

1 shows a plan view of an embodiment of a mold 10 for producing spinal implants with a lid part 10a and a bottom part 10b which has a mechanical connection in the manner of a hinge 13 connected to each other. The lid part 10a and the bottom part 10b are formed as substantially square plates, which consist for example of metal or hard plastic, and in the mutually facing side surface in each case an approximately annular recess 11 is admitted. Will the lid part 10a on the bottom part 10b worked out (cf. 1b ), form the lid part 10a and the bottom part 10b a housing around a cavity, which through the two successive recesses 11 is formed. In the lid part 10a is an injection port 12 arranged, which from the outside of the lid part 10a to the annular recess 11 leads, so that even when folded from the outside a liquid or pasty material 17 into the mold 10 can be filled. In principle, the two annular recesses 11 first with the material 17 , which should be pasty to be infested by brushing or impressions before the lid part 10a and the bottom part 10b be folded. However, there is a risk of air pockets at the contact point. Therefore, preferably, first the shape 10 closed, with the bottom part 10b and the lid part 10a lie positively against each other and are held by manual pressing or a shutter, not shown in this position to each other. Subsequently, through the injection opening 12 the material 17 in the cavity in the mold 10 , For example, by means of a syringe, injected. After curing of the material 17 becomes the shape 10 opened again and that from the hardened material 17 resulting implant can be removed. Form 10 thus allows the molding of a three-dimensional substantially annular implant.

In the injection opening 12 is a sleeve insert 15 used, through which the material 17 can be injected into the mold. This is also the sleeve insert 15 with the material 17 filled. After curing, the sleeve insert 17 turned off and thus the spray nose from the cured material 17 resulting implant is removed, so that a smooth outer side of the implant is ensured.

The inner surface of the annular recesses 11 may be provided in an embodiment not shown with an elastic insert, which also allows the formation of negative angles of the implant. In the area of the contact zones between the two annular recesses 11 in a further embodiment, form beads or lips are arranged on the elastic inserts, which upon folding of the mold 10 engage each other and prevent the formation of a ridge along the outside of the implant.

In a further embodiment, the inner surface of the annular recesses 11 or the inner surface of the elastic inserts provided with a surface coating, which consists for example of a ceramic, Teflon or silicone coating, so that the implant in any case can be easily dissolved out of the tool.

In a further embodiment, not shown, of the mold 10 is in addition to the injection port 12 another opening in the form 10 in the area between the bottom part 10b and the lid part 10a arranged, which serves to receive an insertion tool. To the implant after curing of the material 17 out of form 10 to be able to remove without damaging it, through the further opening an insertion tool into the cavity in the mold 10 introduced, the end of which then through the injection port 12 injected material 17 is flown around. After curing, therefore, the insertion tool is firmly connected to the implant, so that after opening the mold 10 the implant can be removed on the insertion tool. To be able to remove the insertion tool from the implant after implantation of the implant in the intervertebral space, the insertion tool is designed in the manner of a screw or a threaded rod, which can then be rotated out of the implant without damaging the implant.

In an alternative embodiment not shown, the shape 10 equipped with movable pins and / or slides, which from the outside of the housing of the mold 10 can be inserted into the cavity to form holes and / or recesses in the implant can. At these holes, notches or recesses may be after hardening of the material 17 and opening the mold 10 e also with an appropriate instrument, the implant gripped and out of shape 10 be removed.

To the height of the form 10 To vary, so also depending on the operating conditions and individual dimensions of each patient during surgery to make the appropriate implant can, between the lid part 10a and the Bottom part part 10b an element may be interposed as a spacer, for example in the form of a metal plate which also has an annular recess which has the same dimensions as the annular recesses 11 having. By varying the thickness of the metal plate, the height of the resulting implant can thus be varied and adjusted individually for the respective patient.

Because of the recesses 11 in the shape 10 ring-shaped, has in the form 10 through the two annular recesses 11 formed cavity a Durchbauungsbereich 14 on. The construction area 14 allows a bony fusion, especially the cervical, thoracic and lumbar spine, thus ensuring increased stability.

Through the injection opening 12 or an additional not shown further opening, the shape 10 be evacuated before using the material 17 is filled to avoid trapped air and to ensure that the shape 10 completely with the material 17 is filled. To excess material 17 to be able to escape from the cavity, has the shape 10 valve-like openings. These can be formed either by one or more outlet openings, for example, at the injection opening 12 farthest point of the cavity are arranged so that as soon as the material 17 starting from the injection opening 12 spread throughout the cavity and this has completely filled, the material 17 emerges at the opposite outlet opening. The outlet openings can, in order to ensure an even better filling of the cavity, additionally be designed such that they do not open until a certain level of overpressure inside the cavity has been reached.

1c shows a further embodiment of a mold 10 ' , which allows the molding of multiple implants simultaneously. Like reference numerals designate like parts as in FIGS 1a and 1b , In the 1c illustrated form 10 ' differs from the previously described form 10 only in that essentially two forms 10 according to the embodiments described above, to allow the simultaneous molding of two implants, in particular of two implants of different sizes, in order to provide a suitable selection of implants for the respective patient. After trying out a first implant in situs can then be switched to a larger or smaller implant, without this being associated with additional costs or efforts. This approach is also useful because the offered on the market packaging sizes of plastic cements are usually much larger than the necessary amounts for a single implant, the excess remainder usually has to be thrown away unused, since it also cures, but is not shaped accordingly.

Form 10 according to one of the described embodiments can now be used in a method for producing a spinal implant as follows. First, the material 17 , a bone cement or similar material in the liquid or pasty state in the cavity in the mold 10 brought in. At this time, the damaged disc has already been removed in the patient, so that the surgeon knows the dimensions of the resulting disc space. Therefore, before filling the material 17 the cavity of the mold 10 adapted to the individual anatomical conditions, in particular by selecting the height of the implant to be produced and by simultaneous molding of several implants with different diameters. Then the material becomes 17 in the shape 10 cured to form the implant and for operative implantation from the mold 10 taken. Form 10 can then be cleaned and reprocessed and re-sterilized for re-intervention.

The 2 to 8th show different embodiments of an apparatus for producing spinal implants with a mold 20 which is an elastic shell 21 having. In this case, the different features of the embodiments are essentially combined with each other in any way. The same reference numerals designate the same parts.

The elastic shell 21 can be made of a knitted or knitted fabric, or of an elastic plastic such. Silicone, polyethylene or the like, and is preferably sterilizable. The use of an elastic shell 21 allows easier removal of the implant from the mold, since the elastic sheath 21 can be easily demolished after curing of the material, and also allows negative angles in the implant design. Preferably, the inside of the elastic sheath 21 the form 20 a surface coating, such as Teflon or silicone, which the elastic properties of the shell 21 not affected, but a residue-free detachment of the elastic sheath 21 allowed by the implant to be produced.

The 2a to 2f each show a perspective view of the mold 20 whose elastic shell 21 is designed differently to different shapes for the implant enable. 2a shows the shape 20 whose elastic shell 21 is substantially annular, in particular formed with a substantially square cross-section. On one side, preferably the anterior side 26a the form 20 are an injection port 22 and another opening 23 arranged. Through the injection opening 22 becomes a liquid or pasty material in the mold 20 filled where it hardens to form the implant to be produced. The further opening 23 can perform different functions, as will be explained with reference to the following embodiments.

Inside the annular elastic shell 21 the form 20 is a construction area 25 formed, which allows a bony fusion of adjacent to the implant vertebral body and contributes to the increased stability of the operated spine.

At the in 2 B embodiment shown has the elastic sheath 21 the form 20 additionally through the annular outer region of the elastic sheath 21 running bridge 28 on, which can also be filled with the material. The jetty 28 runs approximately parallel to the anterior side 26a the form 20 , This also forms parallel to the anterior side 26a the form 20 two construction areas 25 ,

This in 2c embodiment shown differs from that in 2 B shown only by the fact that the bridge 28 perpendicular to the anterior side 26a is arranged, resulting in two perpendicular to the anterior side 26a running through areas 25 form.

2d shows a further embodiment of a mold 20 , which has several construction areas 25 which consists essentially of several of the cranial side 26c to the caudal side 26d extending through holes are formed.

The embodiment according to 2e has an approximately U-shaped elastic shell 21 on, with also a Durchbauungsbereich 25 in the interior of the U-shaped elastic shell 21 formed.

2f shows an embodiment of a form 20 in which the elastic sheath is H-shaped, depending on the length of the legs of the H one or two Durchbauungsbereiche 25 between the thighs of the H form.

Form 20 can by the different design of the elastic shell 21 be adapted to the individual ideas of the surgeon or the intraoperative conditions. Thus, for example, shaping features, such as the cut-through area in the implant, which is to serve the bone perforation, be changed in size depending on the choice of shape 20 , This is very useful because there are operators who consider different areas of construction to make sense.

In the 3a and 3b is a plan view of the anterior side 26a the form 20 shown while 3c a side view of the embodiment according to 3b represents. First, the anterior side points 26a the injection port 22 on. In addition, there are two more openings 23 represented, which can have different functions.

First, through one of the openings 23 , but in principle also through the injection opening 22 an insertion tool are introduced into the elastic shell, so it is either flowed directly from the filled material or is pressed into the already filled material. The setting tool serves to be able to use the implant without damage in the intervertebral space after curing of the material. As in 7 shown, the insertion tool as a screw 27 or threaded rod, so that it can be unscrewed after curing of the material and implanting the implant from the implant without damaging the implant. In an alternative, not shown. Embodiment, the elastic sheath on channels for receiving metallic elements, with which different holes, recesses or notches can be formed in the implant, on which after curing of the material and tearing off of the elastic sheath 21 appropriate instruments for inserting the implant can attack in the intervertebral space.

One of the other openings 23 , or the injection opening 22 itself, can evacuate the elastic shell 21 be used to ensure that form in the material to be filled no air pockets and the elastic shell is completely filled with the material.

Basically, any of the openings 22 . 23 both for injecting and for evacuating the mold 20 and used to insert an insertion tool.

The injection opening 22 and the other openings 23 can be designed as hose lugs or as Luer-lock connections.

The 4a . 4b and 4c show different embodiments of the elastic sheath 21 , which stabilizing elements 28 on has. The stabilizing elements 28 should ensure certain minimum dimensions of the implant, in particular a certain minimum height. These are in the embodiments according to the 4a and 4b the stabilizing elements in the breakdown area 25 bil Denden side surfaces of the elastic shell 21 let in and run from the cranial side 26c to the caudal side 26d , They prevent the elastic sheath 21 in this direction is compressed too much and thus ensure that the implant receives a certain height. In the embodiment according to 4c whereas the stabilizing element runs from the anterior side 26a to the posterior side 26b to when inserting the elastic sheath 21 to ensure stability in the intervertebral space. The stabilizing elements 28 For example, consist of reinforced material or metal threads. So that the stabilizing elements 28 made of metal do not come into contact with the liquid or pasty material and do not grow into the implant, which are the stabilizing elements 28 arranged in tabs, not shown. This further ensures that the outside of the implant remains relatively flat, since the stabilizing elements 28 do not penetrate into the implant. Are the stabilizing elements 28 formed from material reinforcements, this is given anyway.

In the 9a . 9b and 9c are different embodiments of forms 20 with elastic sheaths 21 shown on its cranial side 26c and / or caudal side 26d having areas formed by substantially rigid material, in which structurings 29 are formed. The structuring 29 may in the manner of cones, pyramids such as according to embodiment in 9a , Teeth, keels or fins such as according to embodiment in FIG 9b , Serrations or nubs such as according to embodiment in FIG 9c be educated. The structuring 29 serve to stabilize the implant used in the intervertebral space and to prevent slipping relative to the adjacent vertebral bodies in that the structuring interlock and tilt in the vertebral bodies.

To excess material from the elastic sheath 21 to be able to leak out and determine whether and when the elastic sheath 21 completely filled with material, has the elastic shell 21 Valve-like openings 30 on, as in the embodiments according to 5a and 5b shown. Preferably, these are valve-like openings 30 designed so that they only open when a certain level of pressure within the elastic shell 21 is reached. This prevents premature leakage of material from the elastic sheath 21 if it is not sufficiently filled. It would be possible to remove the material from the openings 30 to let escape, harden the material and then the at the openings 30 outer hanging material together with the elastic sheath 21 demolish. However, when inserting the elastic sheath 21 in the intervertebral space to adapt the elastic sheath 21 to avoid the anatomical conditions of the patient that the material exits into the intervertebral space is, as in the 5a and 5b shown, the interior of the elastic shell 21 over the valve-like openings 30 with reservoirs 31 connected to receive the excess bone cement or similar material. The reservoirs 31 are also made of the material of the elastic shell 21 formed and are at tearing off the elastic sheath 21 removed from the cured material at the same time. The openings 30 can be either to the outer surface of the elastic shell 21 as in 5a represented or as in 5b shown to the Durchbauungsbereich 25 the elastic shell 21 to open. After completion of the implant also within the cut-through area 25 arranged reservoirs 31 This will be done in one of the construction areas 25 arranged reservoir 31 through an outer shell 32 , a metallic, two-part shell arranged in the outer shell 33 and an inner shell disposed in the metallic shell 34 formed, with the inner shell 34 over the valve-like openings 30 with the elastic shell 21 connected is. The inner shell 34 is a substantially closed bladder, which over the valve-like openings 30 with the elastic shell 21 is connected such that material from the interior of the elastic shell 21 when filling the elastic sheath 21 in the interior of the inner shell 34 can transgress. The two-piece metallic shell 33 is used for punching or shearing the inner shell 34 after curing of the filled material such that after curing, the two parts of the metallic shell 33 be pushed toward each other in the manner of a box with a lid, the edges of the lid and the edges of the box are either in abutment, so that the valve-like openings 30 be punched, or the edges of the lid engage over the box, the valve-like openings 30 sheared off. The outer shell 32 essentially serves the two-piece metallic shell 33 to keep and prevent them from the inner shell 34 solves.

After filling the elastic sheath 21 and curing the material the finished implant from the elastic sheath 21 to be able to remove, is the elastic shell 21 along at least one predetermined breaking line 35 torn open. These fracture lines 35 can through a material weakening, a perfo ration or a material reinforcement be formed. A material reinforcement can in particular by a in or on the inside of the elastic shell 21 extending wire or plastic thread be formed, which with its one end of the elastic sheath 21 sticking out and pulling on this end causes the elastic sheath 21 is torn open. Different embodiments of the predetermined breaking lines 35 equipped elastic shell 21 are in the 6a . 6b and 6c shown.

At the in 6a illustrated embodiment has the elastic sheath 21 several from the anterior side 26a Fracture lines extending to the posterior side 35 on, causing the elastic sheath 21 in several tear-open tabs 36 is split over the predetermined breaking lines 35 connected together and can be demolished separately. In 6b is the top view of the posterior side 26b of in 6a shown embodiment shown.

At the in 6c the embodiment shown by those of the anterior side 26a to the posterior side 26b running predetermined breaking lines 35 formed tear tabs 36 also from the anterior side 26a to the posterior side 26b after attachment to the posterior side 26b back to the anterior side 26 attributed, including the returned tear tabs 36 through the predetermined breaking lines 35 are connected. In 6c they are on the anterior side 26a attached ends of the tear tabs 36 With 37 while the returned ends are denoted by the reference numeral 38 are designated. The returned ends 38 the tear tabs 35 are also on the anterior side 26a attached, for example via an easily detachable adhesive dot 39 to simply touch the returned ends 38 for tearing open the elastic sheath 21 to enable. When pulling on the returned end 38 one of the pull tabs 36 breaks the connection to the adjacent tear tabs 36 along the break line 35 and the connection of the pull-tab 36 on the posterior side 26b also breaks off. Subsequently, the tear tab 36 be deducted without going to the posterior side 26b to have to grab. Due to this embodiment of the tear tabs 36 is possible, the elastic shell 21 from the cured material even in the case that the filled with the liquid or pasty material shell was inserted into the disc space and after relaxation of the vertebra could not be removed, still up and tear.

So that when inserting filled with not yet cured material elastic sheath 21 in the intervertebral space the elastic sheath 21 maintains a certain minimum height, has the elastic sheath 21 in an in 8th illustrated another embodiment extending in the vertical direction shock absorber 45a . 45b on. The embodiment according to 8th shows two different variants 45a . 45b of shock absorbers, with usually only one of the two variants in an elastic shell is used. Both shock absorbers 45a . 45b have one in a tubular sleeve 46 axially movable plunger 47 on, with the movement of the plunger 47 in the sleeve 46 in the variant 45a essentially by friction and in the variant 45b essentially by one in the sleeve 46 arranged spring element 48 is muted. Will the filled with not yet cured material elastic shell 21 placed in the intervertebral space, with the adjacent vertebrae held apart, and then the vertebrae are relaxed, catching the shock absorbers 45 . 45a . 45b Remove the pressure and prevent the elastic sheath from moving in the direction of the cranial side 26c and the caudal side 26d is compressed too much.

Form 20 with the elastic shell 21 according to one of the embodiments described above can be used as follows in a method for producing spinal implants. First, the bone cement or a similar material is filled in the liquid or pasty state in the elastic shell until it is completely filled. The patient has already been prepared so far that the damaged intervertebral disc has been removed and the corresponding intervertebral space is exposed. The filled with the still moldable liquid or pasty material elastic shell 21 is introduced into the intervertebral space and the adjacent vertebrae are relaxed. This will be the elastic shell 21 exactly adapted to the individual anatomical conditions of the respective patient. Once the material has hardened so far that a change in shape is no longer to be feared, which is already the case after 1 to 2 minutes, the elastic shell 21 removed from the intervertebral space to allow the material to cure completely outside the patient. The complete curing process takes about 15 minutes. The intervertebral space and the surrounding tissue thus come neither in contact with the corresponding liquid or pasty material nor are they burdened by the heat generated during curing of the material. Is the material in the elastic shell 21 cured to the desired implant, the elastic sheath 21 torn off and the implant surgically implanted.

Due to the various possibilities of adapting the implant shape to the individual patient conditions and surgeon's wishes are consider the implants made in this way better than industrially prefabricated implants.

10

shape

10 '

shape

10a

cover part

10b

the bottom part

11

recess

12

Injection port

13

hinge

14

Durchbauungsbereich

15

sleeve insert

17

material

20

shape

21

elastic shell

22

Injection port

23

opening

25

Durchbauungsbereich

26a

anterior page

26b

posterior page

26c

craniale page

26d

caudal page

27

screw

28

stabilizing element

29

structuring

30

Valve-like openings

31

reservoir

32

outer shell

33

two-piece metallic shell

34

inner shell

35

Line of weakness

36

pull tab

37

at the anterior side attached end of the tear tab

38

returned end the pull-tab

45a

shock absorber

45b

shock absorber

46

shell

47

tappet

48

spring element

Claims (48)

Device for producing spinal implants according to a method in which bone cement or a similar material ( 17 ) in the liquid or pasty state into a mold ( 10 . 10 ' . 20 ) is introduced, in which the hollow mold ( 10 . 10 ' . 20 ) is adapted to the individual anatomical conditions, in which the material ( 17 ) in the mold ( 10 . 10 ' . 20 ) is hardened to form the implant and in which subsequently the hardened implant for surgical implantation is removed, characterized by a shape ( 10 . 10 ' . 20 ) consisting of one or more parts that allow in their interaction the impression of the three-dimensional implant. Device for producing spinal implants, characterized by a form ( 10 . 10 ' . 20 ) consisting of one or more parts that allow in their interaction the impression of the three-dimensional implant. Device according to claim 1 or 2, characterized in that the one or more parts ( 10a . 10b ) are rigid and form a housing in the interior of a cavity for molding the implant is formed. Device according to one of claims 1 to 3, characterized in that in the form ( 10 . 10 ' ) an injection opening ( 12 ) is arranged. Device according to one of claims 1 to 4, characterized in that the individual parts of the mold ( 10 . 10 ' ) by a mechanical connection ( 13 ), preferably connected by joints and / or self-locking closures. Device according to claim 5, characterized in that the mechanical connections ( 13 ) the individual parts of the mold ( 10 . 10 ' ) hold together in a form-fitting manner. Device according to one of claims 1 to 6, characterized in that the shape ( 10 . 10 ' ) of two parts ( 10a . 10b ), preferably a bottom part ( 10b ) and a lid part ( 10a ), consists. Apparatus according to claim 7, characterized in that the two parts via a mechanical connection in the manner of a hinge ( 13 ) are connected. Device according to one of claims 3 to 8, characterized that in the case an elastic insert consisting of one or more parts is arranged. Device according to claim 9, characterized in that that in the area of the contact zones of the individual parts of the elastic Use of the form beads or lips are arranged. Device according to one of claims 1 to 10, characterized in that the shape ( 10 . 10 ' ) has an opening for receiving an insertion tool. Device according to claim 11, characterized in that that the opening in the region of the contact zone between the bottom and top part of the tool is arranged. Apparatus according to claim 11 or 12, characterized in that the insertion tool in the manner of a screw or a threaded rod is trained. Device according to one of claims 1 to 13, characterized in that the shape ( 10 . 10 ' ) is equipped with movable pins and / or slides for forming holes and recesses in the implants. Device according to one of claims 1 to 14, characterized in that the shape ( 10 ' ) allows the simultaneous impression of several implants. Device according to one of claims 1 to 15, characterized in that the height of the mold ( 10 . 10 ' ) Is variable, preferably by an intermediate element, preferably an element in the form of a metal plate. Device according to one of claims 1 to 16, characterized in that the inside of the mold ( 10 . 10 ' ) has a surface coating. Device according to one of claims 1 to 17, characterized in that in the form ( 10 . 10 ' ) formed cavity at least one Durchbauungsbereich ( 14 ) having. Device according to one of claims 1 to 18, characterized in that the shape ( 10 . 10 ' ) has a connection for evacuating the mold. Device according to one of claims 4 to 19, characterized in that in the injection opening ( 12 ) a sleeve insert ( 15 ) is arranged. Device according to one of claims 1 to 20, characterized in that the shape ( 10 . 10 ' ) has valved openings, which preferably open as soon as a certain level of overpressure within the mold is reached. Device according to claim 1 or 2, characterized in that the shape ( 20 ) of an elastic shell ( 21 ) is formed. Apparatus according to claim 22, characterized in that the elastic sheath ( 21 ) is made of polyethylene or silicone. Device according to claim 22 or 22, characterized in that the elastic sheath ( 21 ) an injection opening ( 22 . 23 ) having. Device according to one of claims 22 to 24, characterized in that the elastic sheath ( 21 ) an opening ( 22 . 23 ) for an insert tool ( 27 ) having. Apparatus according to claim 25, characterized in that the insertion tool in the manner of a screw ( 27 ) or a threaded rod is formed. Device according to one of claims 22 to 26, characterized in that the inside of the mold ( 20 ) has a surface coating. Device according to one of claims 22 to 27, characterized in that the elastic sheath ( 21 ) at least one cut-through area ( 25 ) having. Device according to one of claims 22 to 28, characterized in that the elastic sheath ( 21 ) is substantially annular, U-shaped or H-shaped. Device according to one of claims 22 to 29, characterized in that the elastic sheath ( 21 ) a connection ( 22 . 23 ) for evacuation. Device according to one of claims 22 to 30, characterized in that the elastic sheath ( 21 ) stabilizing elements ( 28 ) having. Device according to one of claims 22 to 31, characterized in that the elastic sheath ( 21 ) at least one anterior to posterior stabilizing element ( 28 ) having. Device according to claim 31 or 32, characterized in that the stabilizing elements ( 28 ) are arranged in tabs. Device according to one of claims 22 to 33, characterized in that the elastic sheath ( 21 ) has on its cranial and / or caudal side (26c, 26d) areas formed by substantially rigid material, in which structurings ( 29 ) are formed. Apparatus according to claim 34, characterized in that the structurings ( 29 ) are formed in the manner of cones, pyramids, teeth, teeth, keels, fins or nubs. Device according to one of claims 22 to 35, characterized in that the elastic sheath ( 21 ) Has channels for receiving metallic elements. Device according to one of claims 22 to 36, characterized in that the elastic sheath ( 21 ) Valve-like openings ( 30 ), which preferably open as soon as a certain level of overpressure inside the elastic sheath ( 21 ) is reached. Apparatus according to claim 37, characterized in that the interior of the elastic envelope ( 21 ) via the valve-like openings ( 30 ) with reservoirs ( 31 ) for receiving the excess bone cement or similar material ( 17 ) connected is. Device according to claim 38, characterized in that the reservoirs ( 31 ) on the outside of the elastic sheath ( 21 ) or in one of the construction areas ( 25 ) are arranged. Apparatus according to claim 39, characterized in that in one of the cut-through areas ( 25 ) arranged reservoir ( 31 ) by an outer shell ( 32 ), arranged in the outer shell metallic, two-part shell ( 33 ) and one in the metallic shell ( 33 ) arranged inner shell ( 34 ), wherein the inner shell ( 34 ) via the valve-like openings ( 30 ) with the elastic sheath ( 21 ) connected is. Device according to one of claims 22 to 40, characterized in that the elastic sheath ( 21 ) along at least one predetermined breaking line ( 35 ) is rupturable. Apparatus according to claim 41, characterized in that the at least one predetermined breaking line ( 35 ) is formed by a material weakening, a perforation or a material reinforcement. Device according to claim 42, characterized in that that the material reinforcement by a running in or on the inside of the elastic sheath Wire or plastic thread is formed. Device according to one of claims 41 to 43, characterized in that the at least one predetermined breaking line ( 35 ) is formed extending from anterior to posterior. Device according to one of claims 22 to 44, characterized in that the elastic sheath ( 21 ) is formed double-layered. Device according to one of claims 22 to 45, characterized in that the elastic sheath ( 21 ) from at least two from the anterior side ( 26a ) to the posterior side ( 26b ) running predetermined breaking lines ( 35 ) tearing tabs ( 36 ) formed from the anterior side ( 26a ) to the posterior side ( 26b ) and after attachment to the posterior side ( 26b ) to the anterior side ( 26a ) are returned. Device according to one of claims 22 to 46, characterized in that the elastic sheath ( 21 ) at least one vertically extending shock absorber ( 45a . 45b ) having. Device according to claim 47, characterized in that the shock absorber ( 45a . 45b ) by a in a tubular sleeve ( 46 ) axially movable plunger ( 47 ), wherein the movement of the plunger ( 47 ) in the sleeve by friction and / or by a sleeve disposed in the spring element ( 48 ) is muffled.