DE20120467U1 - Fastening element for tissue, cartilage and / or bone material - Google Patents

Description

Applicant: BioTissue AG
Attorney file: 46 776 V

Fastening element for tissue, cartilage and/or bone material

The present invention relates to a fastening element for tissue, cartilage and/or bone material and to a transplantation system containing this fastening element. More specifically, the present invention relates to a fastening element for the transosseous fixation of tissue, cartilage and/or bone material, e.g. tissue transplants, bone fragments after fractures, cartilage pieces in traumatic and/or degenerative defects and in osteochondrosis dissecans.

Background of the invention

The secure fixation of tissue, cartilage and/or bone material is a necessary prerequisite for the growth of the fixed material and therefore the healing process. An example of this is the fixation of cartilage transplants in the case of defects in the articular cartilage of the knee, hip, shoulder, etc. To treat these defects, a cartilage biopsy is currently taken from the patient, cells are grown from the removed material and these are introduced into a matrix material that usually consists of stable bioresorbable fibers and, if necessary, a fibrin glue. This tissue material containing the living cells is usually in the form of flat structures such as tissue flaps, discs, etc., the shape of which is adapted to the defect. ,

The tissue material is then placed or inserted by the operating surgeon onto the defect and fixed in place, for example with sutures, pins (in the form of thumbtacks), nails, anchors or fixation rods. Fixation with pins, nails or fixation rods is achieved by driving the fastening element through the tissue material and into the bone. In the case of larger defects, the transplant may even have to be fixed in several places. Fixation

with pins, nails or fixation rods has the disadvantage that, on the one hand, the fixation must be carried out through the transplant, thus damaging it. On the other hand, only a small tensile load can be applied until the transplant has grown, otherwise the fixing element can become loose. If such a "solid" fixing element extends through the transplant, its degradation products are formed directly in the latter. This can, under certain circumstances, lead to inflammatory or even rejection reactions.

The fastening devices currently in use are made of titanium or bioresorbable material such as poly-L,D-lactate or polygluconate, which has the advantage that the fastening element can remain in the body after treatment and is slowly broken down by the body itself. The person skilled in the art knows such materials, for example from EP 0 276 153 and the article by Athanasiou et al., Biomaterials 17 (1996) pp. 83-102.

A currently common and widely used fastening element in the form of a nail is described in EP 0 412 280 and is sold under the brand name "Polypin" by SulzerMedica. This element has barbs on the nail shaft to avoid the problem of loosening described above. However, these increase the circumference of the shaft to be driven through the transplant and thus the risk of damaging the transplant.

It is therefore an object of the present invention to provide a fastening element which overcomes the above-mentioned disadvantages of the prior art.

Summary of the invention

To solve these and other problems and to overcome the disadvantages of the prior art, the present invention provides a fastening element, preferably made of bioresorbable material, comprising a first fastening means for a tension element and a second fastening means for tissue, cartilage and/or bone material, wherein the first fastening means and the second fastening means are connected to one another by a connecting member.

According to a further aspect, the present invention relates to a transplantation system,
comprising a tissue, cartilage and/or bone material and at least one fastening element as described above, wherein the fastening element is
second fastening means for a tissue, cartilage and/or bone material is attached to the tissue, cartilage and/or bone material.

Further preferred embodiments are described in the appended claims.

Short description of the drawing

Fig. 1 is a schematic representation of a fastening element according to a first embodiment of the present invention. ■..:■"-.■■

Detailed description of the present invention

As described above, the invention provides a fastening element comprising a first fastening means for a tension element and a second fastening means for tissue, cartilage and/or bone material, wherein the first fastening means and the second fastening means are connected to one another by a connecting member. . '

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The fastening element according to the invention is fastened to the tissue, cartilage and/or bone material using the second fastening means. This fastening can be carried out before the actual operation, i.e. without the restrictions on the freedom of movement imposed on the surgeon by the geometry of the body and also without time restrictions with regard to the duration of the anesthesia. This represents a considerable simplification for the surgeon and at the same time allows for more precise fixation of the transplant or the tissue, cartilage or bone material to be fixed.

On the other hand, the attachment of the tissue, cartilage and/or bone material (more generally the transplant) can be carried out from "below", i.e. from the side of the bone, for example by sewing or gluing. This avoids piercing the transplant and the associated damage to it. As soon as the transplant and preferably also a traction element are attached, the entire transplant system consisting of the transplant and the attachment element can be introduced into the patient and fixed in place as described below. The attachment element is completely sunk into the bone, for example in a drill hole, and covered by the transplant. At the same time, this avoids further damage to neighboring tissue parts, which can be caused with conventional pins, for example by the nail head "protruding".

The fastening element according to the invention comprises a first and a second fastening means and a connecting member. The first fastening means is a fastening means for a tension element. According to the invention, a tension element is understood to mean all means with which a tensile force can be exerted on the fastening element. The tension element is preferably a thread, very particularly preferably also made of bioresorbable material, or a wire.

Preferably, the first fastening means for a tension element is an element selected from the group consisting of one or more eyelets, a clamping device, one or more hooks, one or more loops, an adhesive point, a soldering point and a locking connection. The tension element is fixed to the fastening element on and via the first fastening means in such a way that a tensile force can be exerted on the fastening element. Most preferably, the first fastening means is one or more eyelets into which a thread can be knotted as a tension element. A design is also possible in which the first fastening means and tension element merge into one another, so that the tension element appears as an extension of the connecting link.

The second fastening means is a fastening means for tissue, cartilage and/or bone material. In principle, this can be any fastening means suitable for fixing this material. The second fastening means is preferably an element selected from the group consisting of one or more eyelets, an adhesive point, a plate, a grid, a net, a clamping device, one or more hooks, one or more loops and a Velcro device. According to the invention, a plate is understood to be a flat end of the connecting member. The plate can be flexible (film) or rigid. According to one embodiment, the plate can be placed on the transplant from below (i.e. from the bone side) and connected to it by sewing, Velcro, etc.

According to another embodiment, the plate (mesh/grid) can be placed on top of the graft. In this case, the connecting member extends through the graft. When a tensile force is applied to the fastening element , the plate presses the graft against the bone and thus holds it in place.. - .■■■·'■■■■■.·■ -. . ■ ■ ' ■ - . ; ■ ■■■■ . .

According to a particularly preferred embodiment, the second fastening means is an eyelet that can be attached to the transplant by sewing. A fastening element in which the first and second fastening means each represent an eyelet is particularly preferred. These eyelets can be rigid or flexible and can basically have any suitable shape. They are preferably rounded. The pulling element is preferably a thread or wire.

In the fastening element according to the invention, the first and second fastening means are connected to one another by a connecting member. This connecting member can connect the fastening means rigidly or flexibly to one another. Accordingly, the connecting member itself can be rigid or flexible. Preferably, the connecting member is flexible. The connecting element can also be omitted, so that the fastening means are directly connected to one another, for example via an adhesive or soldering point.

The connecting link can basically be designed in any form suitable for connecting the fastening means, as long as it has sufficient tensile strength. The connecting link is preferably in the form of a rod, a thread, a hollow cylinder, a flattened band or a chain. The connecting link can have other elements such as barbs etc. to prevent the fastening element from slipping in the bone. The connecting link is particularly preferably a possibly flexible rod with a round cross-section.

In preferred embodiments, the connecting member has a smaller diameter than at least one of the first fastening means and the second fastening means.

The dimensions of the fastening element according to the invention are usually adapted to its respective application. This application can be in human and veterinary medicine. In particular, the dimensions of the fastening element are adapted to the bore width through the bone, to the tissue thickness and to the thickness of the bone. For cartilage tissue fixation in the knee of an adult human, these dimensions are usually in the range of 1 to 100 mm total length, 0.5 to 10

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mm outer diameter and approx. 0.5 to 10 mm length of the fastening elements in the case of eyelets.

The fastening element according to the invention basically consists of any suitable material such as metals (e.g. titanium, Ti alloys, etc.) or a bioresorbable material, whereby the terms "bioresorbable" or "biodegradable" are used synonymously for the purposes of the present application. Basically, any material with the required mechanical and physical properties such as tensile strength, sterilizability, compatibility, etc. is suitable. The choice of material will depend not only on its mechanical properties, in particular its tensile strength, but also on its decomposition rate in the body in the case of bioresorbable material with regard to the indication under consideration and the tissue to be fixed. Suitable materials are known to the person skilled in the art. The fastening element according to the invention preferably consists at least partially, most preferably completely, of bioresorbable material.

Preferably, the bioresorbable material is selected from the group consisting of polyglycol, poly-D,L-lactic acid, poly-L-lactic acid, poly-D-lactic acid, polydioxanone, fibrin, fibrin derivatives, hyaluronic acid, hyaluronic acid derivatives, random and block copolymers thereof and mixtures of the aforementioned. Most preferably, it is the 70/30 copolymer of poly-D,L-lactide and poly-L-lactide described in European Patent Application 0 412 280.

The fastening element according to the invention can be produced from the (co)polymers mentioned by any suitable molding process such as injection molding, melt molding, compression molding, etc. The fastening element is preferably produced in one piece by such a process, i.e. it has no connecting seams.

The fastener may further comprise an X-ray marker. The X-ray marker may be located along the central axis of the link, at one or both ends thereof, or centrally in the link. For example, the marker may be incorporated into a cavity in the link during the manufacturing process. The marker allows the exact position of the fastener to be determined.

ments in the body or joint and to track the decomposition of the fastening element through its disappearance. The X-ray marker is preferably selected from common X-ray contrast media for medical purposes such as barium sulfate, calcium sulfate, zinc oxide, lead oxide, iodine compounds, etc.

The tissue material that is to be fixed using the fastening element according to the invention can in principle be any suitable tissue material, such as natural tissue taken from a donor, but also semi-synthetic or fully synthetic tissue. The tissue preferably comprises a semi-synthetic tissue. This is preferably the above-described preferably flat matrix made of bioresorbable fibers and optionally a bioadhesive such as a fibrin adhesive with living cells in the matrix. These can be selected, for example, from cartilage cells, muscle cells, bone-forming cells, chondrocytes, osteoblasts or periosteal cells. Autologous or allogeneic tissues, which are produced in particular using tissue engineering methods, are also suitable.

According to a special embodiment, the fastening element itself can also be completely or partially populated with living cells as above. These can be different from those of the transplant or identical to it. For example, it can be a cartilage transplant as tissue. The fastening element can then be populated with bone cells (osteoblasts), for example.

In a second aspect, the invention relates to a transplantation system comprising a tissue, cartilage and/or bone material as described above and at least one fastening element as described above, preferably made of bioresorbable material, wherein the fastening element is fastened to the tissue, cartilage and/or bone material via the second fastening means for a tissue, cartilage and/or bone material. Preferably, the transplantation system additionally comprises a tension element as defined above. The transplantation system according to the invention can comprise several fastening elements, preferably 1 to 10, more preferably 1 to 4 fastening elements. : ■ ■ ■

According to a preferred embodiment, a transplantation system is provided, comprising one or more fastening elements preferably made of bioresorbable material, in which the first and the second fastening means each represent an eyelet, the tissue material is a preferably flat matrix of bioresorbable fibers and optionally fibrin glue with living cells located in the matrix and the tension element, if present, is a thread or wire.

The use of the fastening element according to the invention or the transplantation system according to the invention will now be illustrated using a defect in the articular cartilage. Starting from the defect area, a minimal hole is first drilled through the bone. The tension element is then threaded through the hole, e.g. using a needle. The transplantation system is then pulled into the defect site by pulling on the tension element. The entire fastening element can be sunk into the hole so that only the tissue remains on the outside in the joint socket. The fastening element, including the tissue, is then fixed to the bone by knotting the tension element. The first fastening element can protrude from the bone at the end of the hole opposite the tissue, but this does not have to be the case.

Fig. 1 shows a particularly preferred embodiment of the transplantation system 1 according to the invention. In this system, the first fastening means 2a and the second fastening means 2b are each designed in the form of an eyelet. The fabric material 3 comprises a matrix 4 designed in the form of a rectangle, made of bioresorbable fibers 5 and fibrin glue and living cells 6 located in the matrix. The tension element is a thread 7.

The foregoing description of the preferred embodiments is intended to illustrate the invention only and not to limit it.

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Claims (21)

1. Fastening element comprising a first fastening means for a tension element and a second fastening means for tissue, cartilage and/or bone material, wherein the first fastening means and the second fastening means are connected to one another by a connecting member. 2. Fastening element according to claim 1, wherein the first fastening means for a tension element is selected from the group consisting of one or more eyelets, a clamping device, one or more hooks, one or more loops, an adhesive point, a soldering point and a snap-in connection. 3. Fastening element according to one of the preceding claims, wherein the second fastening means for tissue, cartilage and/or bone material is an element selected from the group consisting of one or more eyelets, an adhesive point, a plate, a grid, a net, a clamping device, one or more hooks, one or more loops and a Velcro device. 4. Fastening element according to one of the preceding claims, in which the first and the second fastening means each represent an eyelet. 5. Fastening element according to claim 2, 3 or 4, wherein the eyelets have a rounded shape. 6. A fastener according to any preceding claim, wherein the connecting member between the first and second fasteners is flexible. 7. A fastening element according to any one of the preceding claims, wherein the connecting member is in the form of a rod, a thread, a hollow cylinder, a flattened band or a chain. 8. A fastener according to any preceding claim, wherein the connecting member has a smaller diameter than at least one of the first fastening means and the second fastening means. 9. A fastener according to any preceding claim, wherein the connecting member is a rod of round cross-section. 10. Fastening element according to one of the preceding claims, wherein the tension element is a thread or wire, preferably made of bioresorbable material. 11. Fastening element according to one of the preceding claims, which consists of bioresorbable material. 12. Fastening element according to claim 11, consisting of a bioresorbable material selected from the group consisting of polyglycol, poly-D,L-lactic acid, poly-L-lactic acid, poly-D-lactic acid, polydioxanone, fibrin, fibrin derivatives, hyaluronic acid, hyaluronic acid derivatives, random and block copolymers thereof and mixtures of the foregoing. 13. Fastening element according to one of the preceding claims, further comprising an X-ray marker. 14. A fastener according to claim 13, wherein the X-ray marker is arranged along the central axis of the connecting member, at one or both ends thereof, or centrally in the connecting member. 15. Fastening element according to one of claims 13 or 14, wherein the X-ray marker is selected from conventional X-ray contrast agents for medical purposes. 16. Fastening element according to one of the preceding claims, wherein the fabric material comprises a preferably flat matrix of bioresorbable fibers and living cells located in the matrix. 17. The fastener of claim 16, wherein the cells are selected from the group consisting of cartilage cells, muscle cells, bone forming cells, chondrocytes, osteoblasts and periosteal cells. 18. Fastening element according to one of the preceding claims 1 to 17, which is populated with living cells selected from the group consisting of cartilage cells, muscle cells, bone-forming cells, chondrocytes, osteoblasts and periosteal cells. 19. A transplantation system comprising a tissue, cartilage and/or bone material and at least one fastening element according to one of claims 1 to 18, wherein the fastening element is fastened to the tissue, cartilage and/or bone material via the second fastening means for a tissue, cartilage and/or bone material. 20. Transplantation system according to claim 19, additionally comprising a tension element. 21. Transplantation system according to claim 19 or 20, wherein the fastening element is made of bioresorbable material and wherein the first and the second fastening means each comprise an eyelet, the tissue material is a preferably flat matrix of bioresorbable fibers and optionally a fibrin glue with living cells located in the matrix and the tension element, if present, is a thread or wire.