EP1732481A2

EP1732481A2 - Application aid for the treatment of bone defects

Info

Publication number: EP1732481A2
Application number: EP05716349A
Authority: EP
Inventors: Arne Briest
Original assignee: Ossacur AG
Current assignee: Ossacur AG
Priority date: 2004-03-26
Filing date: 2005-03-24
Publication date: 2006-12-20
Also published as: WO2005092251A2; US20080039849A1; DE102004016397A1; WO2005092251A3

Abstract

Disclosed is an application aid (1) for introducing a material (12) used for the treatment of bone defects into a natural bone or a natural bone structure. Said application aid (1) comprises a largely flexible, tubular or sleeve-shaped outer part (2) that is composed of at least two components (3, 4) which can be coaxially moved into each other, a largely flexible, preferably tubular or sleeve-shaped inner part (7), and a discharge port (11) for the material, preferably on the outer part (2). The inventive application aid is preferably embodied such that at least one element which can be moved radially outward at least in part is provided in the interior. Said element represents particularly a balloon.

Description

Description Application aid for the treatment of bone defects

The invention relates to an application aid for introducing a material for the treatment of bone defects into a natural bone or a natural bone structure, and to a kit which comprises such an application aid.

A wide variety of inorganic, organic or biological materials are used to effectively treat bone defects. These materials can serve to fill the bone defects, but can also promote the regeneration of the bone, for example by appropriate growth factors.

However, the application of the appropriate material for the treatment of bone defects is often difficult. While certain bone structures, e.g. B. the jawbone, is still relatively easy to introduce the material into the defective bone, this is the case with other bone structures, e.g. B. tubular bones and in the vertebrae, comparatively difficult. This applies in particular to materials that cannot be applied in liquid or comparatively low-viscosity form, but are, for example, in the form of a solid.

A large number of application aids are known from the medical field, but are mainly intended for the treatment of blood vessels and vascular surgery. However, such application aids, for example for the so-called stents, are not suitable for the treatment of bone defects. Accordingly, the object of the invention is to provide an application aid by means of which material for the treatment of bone defects can be introduced into a natural bone or a natural bone structure. In particular, this application aid should also be able to deliver materials that are present as solids, for example with a cotton-like consistency, in bone structures that are relatively difficult to access, such as long bones or vertebrae.

This object is achieved by the application aid with the features of claim 1. Preferred embodiments of this application aid are shown in the dependent claims 2 to 18. Claim 19 defines a kit for the treatment of bone defects, which comprises an application aid according to the invention. The wording of all claims is hereby incorporated by reference into the content of this description.

According to the invention, the application aid for introducing the

Materials for the treatment of bone defects, a largely flexible, tubular or sleeve-shaped outer part, which consists of at least two components that can be moved coaxially one inside the other, a largely flexible, preferably tubular or sleeve-shaped inner part, and a discharge opening for the material, which is preferably provided on the outer part ,

In other words, the application aid according to the invention can also be described in such a way that the outer part is formed from a type of outer catheter and a type of inner catheter. The coaxial displacement of the outer catheter relative to the inner catheter removes the material contained in the application aid through the discharge opening Application help carried out. Inside the outer part, which consists of the outer catheter and the inner catheter, there is an inner part in the manner of a further catheter, which is provided, for example, for the passage of a guide wire for the application aid. The function of all parts of the application aid will be explained in more detail later in connection with the preferred embodiments and in the figure.

The application aid according to the invention preferably has engagement means on the components of the outer part, which are provided for displacing these components against one another / into one another. These attacking means are preferably handles, for example in the form of suitable shapes or protuberances, which enable the user to handle the application aid in the intended manner.

As already indicated, the application aid according to the invention preferably has at least one guide means with the aid of which the application aid is guided to the application site. Such guide means are known for example in the form of so-called guide wires. The guide means extends essentially over the entire length of the application aid. It is preferably arranged inside the inner part, which may be tubular or sleeve-shaped, preferably in the manner of a catheter.

In a further development, the discharge opening for the material is formed at the end of the application aid facing the later application location, this end preferably being designed in the manner of a tip. This facilitates the advancement of the application aid in the direction of the application site. In preferred embodiments, this tip is with the discharge opening on the outer part. However, the application aid can also be used in such embodiments. be structured that the tip with the discharge opening is on the inner part. This can be solved, for example, in such a way that a catheter provided as an inner part with a comparatively small cross-section first expands at the corresponding end and then tapers back towards the discharge opening in order to allow the material to exit through the discharge opening. In a corresponding manner it can also be provided that a corresponding component, which forms the tip with the discharge opening, is placed on the inner part.

In order to enable the material to easily exit the application aid, the end of the application aid facing the application site can be constructed with the discharge opening in such a way that the discharge opening widens when the material is discharged. This can happen, for example, in that the corresponding end of the application aid is made of a thinner material than the remaining body of the application aid. If necessary, a different material can be used for the end than for the remaining body of the application aid, this material then being easier to stretch so that the discharge opening widens when the material is discharged. These embodiments are particularly advantageous if, as already described, the discharge opening is located at an end of the application aid shaped like a tip.

In further preferred embodiments of the application aid according to the invention, at least one element is provided in the interior of the outer part, which is at least partially movable radially outwards. This element is preferably membrane-like or foil-like. Depending on the use, the element, preferably the membrane or film, can be impermeable or permeable, for example porous or porous. Permeable membranes / foils enable, for example, a mass transfer through the membrane / foil as well as bone growth through the membrane / foil. Furthermore, the element, preferably the membrane or film, can be a have sufficient mechanical strength and rigidity to provide a support function for the applied material and, if necessary, for the renewable bone.

In the embodiments with the additional element, it is achieved that the material contained in the application aid can be moved or pressed radially outwards before and in particular after the material has been discharged from the application aid in order to introduce it into the bone or the bone structure. The element provided in the interior of the outer part thus assumes a support function for the material, at least for a short time, in order to convey it into the bone structure and hold it there. This is particularly advantageous in the case of tubular bones or vertebral bones if the material provided for the treatment of the bone defects is to be placed inside the tubular bone or the vertebra, in particular conveyed to the inner walls of these bone structures. This can then be done by moving the element or elements radially outward, for example by sorting or pressing on these elements.

In the preferred embodiments of the application aid according to the invention described last, the elements mentioned are preferably attached to the inner part or at least partially form the inner part itself. This has the advantage of a simplified construction.

In order to effect the movement of the elements radially outwards, the elements can preferably be arranged on the outer surface of a balloon-like element. In an alternative preferred embodiment, the elements themselves form the wall of a balloon-like element. In both cases, the balloon-like element then ensures that the material for the treatment of the bone defects can be moved radially outwards or pressed. In accordance with the above The balloon-like element is preferably attached to the inner part or forms part of the inner part. Such designs are realized, for example, in such a way that the balloon-like element is attached to at least two points on the outer circumference of the inner part and in this way the volume of the balloon is defined between the inner part and the inner wall of the balloon-like element. Such an embodiment is also shown in the drawing for this application. In other such embodiments, the balloon-like element forms part of the inner part itself. The inner part is closed on the side facing the application site and expanded to form the balloon-like element. In this way, the inside of the balloon-like element is accessible from the outside via the inner part and can thus be filled, for example, with the material for the treatment of bone defects.

In the described embodiments with a balloon-like element, this balloon-like element is preferably inflatable. For this purpose, the balloon-like element can be subjected to pressure, in particular air pressure, via the inner part itself or via a hose which is passed through the inner part. In the case of the versions in which the balloon-like element forms an (integrated) part of the inner part, the balloon is inflated directly, i. H. also over the inner part. This is realized in that the part of the inner part leading up to the balloon-like element is not inflatable, for example made of metal, and is followed by the inflatable balloon-like element. In all of the embodiments discussed, the pressurization can be reversible, i. H. after the balloon-like element has fulfilled its function, the pressure can be removed and the balloon-like element virtually collapses again.

In alternative designs, the balloon-like element can preferably be self-expanding, ie it moves itself radially outward without the application of pressure. This can, for example, can be realized by introducing the balloon-like element into the application aid under an external pressure load, or in that the balloon-like element is made from a so-called shape memory material. Such materials, for example metal alloys such as NiTi, but in particular also plastic materials, are known to the person skilled in the art. Under certain conditions, for example temperature conditions, they return to their original shape and thus virtually remember this original shape. This shape memory effect can be used in connection with the present invention. If the actual function of the balloon-like element is also to be ended after a certain time in these cases, the collapse of the balloon-like element can be brought about here by applying an external negative pressure (suction).

Depending on the medical application, it can be provided that the preferably membrane-like or foil-like elements or the balloon-like element remain or not in the bone structure. If the elements mentioned or the balloon are to be removed again, the easiest way to do this is to attach them to the inner part or at least partially form the inner part. This automatically ensures removal when removing / pulling out the application aid from the bone structure.

If the elements mentioned or the balloon-like element are intended to fulfill their function, in particular a supporting function, over a certain period of time after removal of the application aid, they are detachably attached, in particular to the inner part. In this way, all of these elements can remain in the bone structure. Then the material from which the elements are made can be selected depending on the respective medical situation. If the element, in particular the balloon, should cease to function after a certain time ren, a bioresorbable material is preferably used. In principle, these can also be metals such as magnesium or iron, which are also considered to be bioabsorbable. However, the use of bioabsorbable plastics is preferred. The use of bioabsorbable materials ensures that the element / balloon dissolves after a certain time. If the element / balloon is to perform its function for an indefinite period of time, a biocompatible but not bioresorbable material, for example a biocompatible metal such as titanium, is used. In this way, the construction of the application aid according to the invention can be adapted to a wide variety of applications.

Depending on the medical situation, the structure or the surface of the elements used, including the balloon, can also be modified. For example, in order to achieve good bone regeneration, the element or the balloon can be made from a porous membrane-like material, so that the bone can grow through this membrane and a material exchange through the membrane is possible. However, cases are also conceivable in which such a membrane-like structure of the element is not advantageous, so that essentially closed foils can be used in such cases.

In a further development, marking means, in particular for X-ray detection, can be provided on the outer part and / or on the inner part of the application aid according to the invention. In this way, for example, the relative displacement of the components of the outer part into one another / relative to one another or the discharge of the material from the application aid can be checked.

In particularly preferred embodiments of the invention, the application aid described so far is provided with a material for the treatment. filled with bone defects. This material can in principle be any inorganic, organic or biological material that is known for such a treatment of bone defects. Solid materials, in particular those with a comparatively soft consistency, are preferably used for the filling. For example, these can be biological materials such as those sold by the applicant under the names Colloss® and Targobone®.

In a further development, in the application aid filled according to the invention, the outer part, ie. H. the space defined within the outer part is at least partially, preferably completely, filled with the material.

In these embodiments, it is preferred, on the one hand, if essentially only the volume between the inner part or the possibly present preferably membrane-like or foil-like elements (balloon) and the wall of the outer part is filled with the material. The material is therefore between the outer surfaces of these elements or the balloon and the (inner) wall of the outer part or its components.

On the other hand, it is also preferred if essentially only the volume within the preferably present membrane-like or foil-like elements (balloon) is filled with the material. In these cases, the material is only inside the space defined by the elements or inside the balloon. However, the embodiment in which both the volume between the elements / balloon and the wall of the outer part and the volume inside the elements / balloon is filled is also preferred. IC

Finally, as mentioned, the invention comprises a kit for the treatment of bone defects, which comprises at least one application aid, as has been described so far.

As is apparent from the description so far, the invention offers a number of advantages. With the claimed application aid, it is in fact easily possible to convey the materials provided for the treatment of bone defects directly to the application site in the bone structure. This applies in particular to bone structures that are difficult for the attending physician to access. These are in particular tubular bones or vertebrae. With the application aid, it is possible to discharge the preferably solid material and, in the case of the versions with the movable elements or the balloon, to move or press this material against the defective bone structure. In this way, the material is transported specifically to those places where bone growth or bone regeneration is to take place. Depending on the material used, the application aid can then provide a temporary or permanent support function for this material. It will often suffice if the material is pressed against the bone structure only for a comparatively short time. Many materials, such as biological materials with a protein content in particular, then adhere to the bone structure on their own, so that continuous support is not necessary. In these cases, the supporting elements or the balloon can be withdrawn again or made from a bioabsorbable material. If a longer-lasting support function is required, as is necessary, for example, in the case of regeneration of vertebral bones with a previously required straightening of the vertebrae, these elements or the balloon can be made of a biocompatible material of sufficient strength, which maintains its support function permanently or at least until the regrowing bone itself can take on this support function. The described and further features of the invention result from the following drawing in conjunction with the claims. The individual features can be implemented individually or in combination with one another.

The drawing shows:

Fig. 1 is a schematic cross-sectional view of an application aid according to the invention or an applicator according to the invention.

The application aid 1 shown in FIG. 1 has an elongated, tubular outer part 2 in the manner of a catheter, which consists of the two components 3 and 4, which are at least partially inserted into one another. Accordingly, the components 3 and 4 can also be defined as an outer catheter or an inner catheter. On the outer circumference of the components 3 and 4 of the outer part 2 there are holding or handles 5 and 6, with the aid of which the component 3 can be displaced relative to the component 4.

Inside the outer part 2 there is also an elongated, tubular inner part 7, which is designed like a catheter and can accordingly also be referred to as a (further) inner catheter. The components 3 and 4 of the outer part 2 and the inner part 7 are preferably made of plastic.

A guide wire (not shown) can be introduced within the inner part 7, with the aid of which the application aid 1 can be advanced in the body in the direction of the application site.

In the area of the application aid 1, which, when used, faces the application site (“front” Vdistal; in the right side in the figure) is on a (rotationally symmetrical) balloon-like element 8 is attached to the inner part 7. With the aid of the hole 9 provided in the inner part 7, this element 8 can be pressurized from the outside, for example via the (“rear” / proximally arranged) adapter 15, and correspondingly expanded radially outwards. This can also be done in the application aid 1 contained material 12 (between the balloon-like element 8 or the inner part 7 and the wall of the component 3 of the outer part 2) for the treatment of bone defects is moved radially outwards and is pressed, for example, against a bone structure into which the application aid 1 has advanced ,

To discharge the material 12 from the application aid 1, the latter has at its end facing the application site (see FIG. 1 on the right) a discharge opening 11 which, according to FIG. 1, is provided at the end shaped as a tip 10. So that the opening 11 widens when the material 12 is discharged, the wall thickness of the component 3 of the outer part 2 is made thinner in the region of the tip 10 than in the other regions of this component 3 (not shown in the figure).

In order to be able to track the displacement of the component 3 of the outer part 2 relative to the component 4 of the outer part 2 under X-ray control, there are corresponding markings 13 and 14 on the outer circumference of the components 3 and 4.

An application aid 1, for example contained in a kit, as shown in FIG. 1, accordingly works as follows:

The application aid 1 filled with the material 12 is introduced into the patient's body in the usual way during the operation by the attending physician and advanced to the intended application site. In the case of a tubular bone, a hole can be drilled in the tubular bone and the application aid 1 under X-ray control can be introduced into the interior of this long bone. Once the application site has been reached, component 3 of the outer part 2 is moved back relative to the component 4 of the outer part 2 until the balloon-like element 8 with the material 12 surrounding it at least partially protrudes from the discharge opening 11. Then the balloon-like element 8 (possibly already pressurized beforehand) is further inflated or expanded in order to deliver the material 12 into the interior of the bone structure, for example to press it against the inner wall of the tubular bone. Then, in the event that the balloon-like element 8 remains in the bone, this element 8 is uncoupled from the inner part 7 (not shown in FIG. 1), or the balloon is allowed to collapse and is pulled out again together with the application aid 1 Bones out.

Claims

claims

Application aid (1) for introducing a material (12) for the treatment of bone defects into a natural bone or a natural bone structure, with a largely flexible, tubular or sleeve-shaped outer part (2) which consists of at least two components (3, 4), a largely flexible, preferably tubular or sleeve-shaped inner part (7), and a discharge opening (11) for the material, preferably on the outer part (2).

Application aid according to Claim 1, characterized in that gripping means, preferably handles (5, 6), are provided on the components (3, 4) of the outer part (2) for the purpose of shifting them into one another.

Application aid according to Claim 1 or Claim 2, characterized in that at least one guide means, preferably in the manner of at least one guide wire, is provided which extends essentially over the entire length of the application aid, preferably within the inner part.

Application aid according to one of the preceding claims, characterized in that the discharge opening (11) for the material (12) is provided at an end of the application aid (1), preferably the outer part (2), which is designed in the manner of a tip (10).

5. Application aid according to one of the preceding claims, characterized in that in the interior of the outer part (2) at least one preferably membrane-like or film-like element (8) is provided which is at least partially movable radially outwards.

6. Application aid according to claim 5, characterized in that the preferably membrane-like or film-like elements (8) on the inner part (7) are attached or at least partially form the inner part.

7. Application aid according to claim 5 or claim 6, characterized in that the preferably membrane-like or film-like elements are arranged on the outer surface of a balloon-like element.

8. Application aid according to claim 5 or claim 6, characterized in that the preferably membrane-like or film-like elements (8) form the wall of a balloon-like element.

9. Application aid according to claim 7 or claim 8, characterized in that the balloon-like element (8) is inflatable, preferably the inner part (7) itself can be pressurized and / or a hose-like element is passed through the inner part.

10. Application aid according to claim 7 or claim 8, characterized in that the balloon-like element is self-expandable, preferably made of a shape memory material.

11. Application aid according to one of claims 6 to 10, characterized in that the preferably membrane-like or film-like elements and / or the balloon-like element are releasably attached.

12. Application aid according to one of claims 5 to 11, characterized in that the preferably membrane-like or film-like elements and / or the balloon-like element are made of a bioresorbable material, preferably a bioresorbable plastic.

13. Application aid according to one of the preceding claims, characterized in that marking means (13, 14) are provided on the outer part (2) and / or on the inner part for detecting the relative displacement of the components of the outer part and / or for detecting the discharge of the material.

14. Application aid according to one of the preceding claims, characterized in that the application aid (1) is filled with a material (12) for the treatment of bone defects.

15. Application aid according to claim 14, characterized in that the outer part is at least partially, preferably completely, filled with the material.

16. Application aid according to claim 15, characterized in that essentially only the volume between the inner part and / or the possibly present preferably membrane-like or foil-like elements and the wall of the outer part is filled with the material.

17. Application aid according to claim 15, characterized in that essentially only the volume within the optionally present preferably membrane-like or foil-like elements is filled with the material.

18. Application aid according to claim 15, characterized in that, if present, preferably membrane-like or film-like elements, both the volume between these elements and the wall of the outer part and the volume within these elements is filled with the material.

19. Kit for the treatment of bone defects, characterized in that it comprises at least one application aid according to one of the preceding claims.