CZ2007283A3 - Full replacement of cartilage and subchondral bone - Google Patents

Abstract

Total cartilage and subchondral bone replacement consists of at least two interconnected parts, namely the contact part (1) and the replacement body (2). Contact part (1) has identical or close material properties as hyaline cartilage. The replacement body (2) has identical or close material properties to that of subchondral bone. Preferably, the contact part (1) is inserted into the body of the replacement (2) by means of a pin (6) and a lock (3). The replacement body (2) can have one bore (4) in the bottom half, or even cross holes (5), which will be filled with suitable biological material, such as fine cancellous debris, which will contribute to the biomechanical stability of the artificial restoration in the deep redevelopment site. defect.

Description

(57)

The cartilage and the sacral bone are composed of at least two interconnected parts, namely the contact piece 11) and the substitute body (2). The contact part (I) has identical or close material properties to the hyalinthic cartilage of the substitute (2) having identical or close material properties to the subchondral scythe. Advantageously, the contact part (11) is inserted in the summer of the restoration (2) by means of a pin (fit and lock) (3). which, when implanted, will be filled with suitable biological material, such as fine spongy pulp, which will contribute to ensuring the bioniechai stability of artificial replacements at the deep-de-sac site.

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Total replacement of cartilage and subchondral bone

Technical field

The invention relates to artificial total replacement of cartilage and a part of subchondral bone.

BACKGROUND OF THE INVENTION

Chondral defects and degenerative changes in hyaline cartilage, including subchondral bone disorders, are not yet successfully solved. Several methods have been developed in the Czech Republic and abroad to treat deep chondral defects. In recent years, these defects have been most commonly treated by transplantation of autologous chondrocytes, which are bound to carriers which are usually hyaluronic acid esters (for example, Hyalograft C). For other methodologies the application of cylindrical osteochondral autografts was experimentally verified. spongy pulp, application of Poles of D-L-lactide carriers and other biological substrates.

Stedmann mosaicplastics or microfractures are applied in areas of greatest contact stress and less extensive disorders.

A disadvantage of hitherto known methods of treating deep disorders of subchondral bone is their limited applicability, especially in terms of age. In most methods used, there is an age restriction on the success rate of treatment. Postoperative results show that previously applied methods and biomaterials, where, for example, autologous chondrocytes are transplanted to sites with clearly limited disorders, are effective only in younger patients.

In the localities of disorders mostly immature cartilage develops. A disadvantage is also the development of mild convex depressions (in places treated with chondral defects), which are biomechanically a consequence of unbearable tissue and, generally, a biological consequence of its immaturity.

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SUMMARY OF THE INVENTION

These deficiencies are largely eliminated by the total replacement of cartilage and subchondral bone, which consists essentially of at least two interconnected parts, the contact part and the replacement body, and of different material properties.

The contact portion is a polymeric material (such as HEMA) having the same or very close material properties as hyaline cartilage and having the ability to increase its volume in the synovial fluid. The body of the substitute consists of a polymeric material (for example a cycloolefin blend) having the same or very close material properties as the subchondral scythe. For proper function it is advantageous that the contact part is bound to the body of the restoration by means of a bolt with a shaped mechanical lock which, when using HEMA and similar material, has the possibility to swell the restoration body directly in the synovial fluid environment or externally in saline. In other cases, the contact part is pressed, glued into the body of the restoration, or the parts are otherwise mechanically joined. The replacement body may be composed of multiple parts of polymeric materials such that their material properties more accurately follow the continuously changing mechanical properties of the surrounding living tissue. The contact piece is positioned in the joint space so that its top is in the plane of the cartilage surface and its lower part is in the subchondral bone or only in the lower quarter of the cartilage thickness. The contact piece may also be placed below the surface of the cartilage surface and the replacement body in the subchondral bone. The space between the top of the artificial substitute and the plane of the cartilage surface is filled, for example, with autologous chondroblasts transferred from unloaded cartilage sites. Cavities in the cartilage body are used for biological fixation of the replacement, for example by means of a bone graft.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical solution will be explained in more detail by means of the drawing, in which FIG. 1 is a view (left) and a sectional view of the total subchondral bone and cartilage replacement (right), FIG. 2 and FIG. in the fault area.

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DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a specific embodiment of total cartilage and subchondral bone replacement according to the invention. The contact part 1 is inserted into the body of the restoration by means of a pin 6 with a lock 3. Advantageously, the IIEMA contact piece can thus be anchored by inserting it into the body of the restoration 2 in a dry state, gradually swelling into the final position. In the case of another material, for example based on silicone or polyurethane, the assembly would be performed by molding. Due to the better sliding properties of the hinge surface of the contact piece 1, it is preferable to use a discontinuous material such as a porous hydrogel which has the ability to hold a small amount of synovial fluid which also has a lubricant function in the joint. The replacement body 2 has a cylindrical shape. For better fixation of the total prosthesis in the articular part of the body skeleton, the prosthesis body 2 is vertically square or provided with longitudinal notches. The body of the restoration 2 has a bore 4 in its lower half, which will be filled with suitable biological material, for example spongy pulp. which will ensure the biomechanical stability of the artificial restoration. Possible transverse openings 5 in the lower half of the restoration body 2 will ensure a biological firm attachment of the total replacement of the cartilage and part of the subchondral bone. In the case of larger joint defects, one contact part 1 can be made with several suitably positioned locks 3, which are subsequently fixed to several replacement bodies 2 located in the articular skeleton of the human body.

Industrial applicability

Total replacement of cartilage and subchondral bone can be used in healthcare to treat deep chondral and subchondral defects, especially in the elderly.

Claims (13)

PATENT CLAIMS 1. Total cartilage and subchondral bone replacement, characterized in that it comprises at least two interconnected parts, a contact part (1) and a replacement body (2) of different material properties. Total cartilage and subchondral bone replacement according to claim 1, characterized in that the connected parts (1) and the replacement body (2) have a cylindrical shape or are vertically angular or have one or more longitudinal notches. Total cartilage and subchondral bone replacement according to claims 1 and 2, characterized in that the contact piece (1) has material properties equal to or close to the material properties of cartilage. The total replacement of cartilage and subchondral bone according to claims 1 to 3, characterized in that the upper part of the contact part (1) is made of a polymer material, preferably hydromethyl methacrylate or silicone or polyurethane. Total cartilage and subchondral bone replacement according to claims 1 to 5, characterized in that the contact part (1) is formed by either a continuous material or a discontinuous material, preferably spongy. A total replacement of cartilage and subchondral bone according to claims 1 to 6, characterized in that the contact part (1) is formed of a material having the possibility to also bind synovial fluid. Total cartilage and subchondral bone replacement according to one of Claims 1 to 7, characterized in that the contact part (1) is preferably also attached to the supported anchoring parts. · »V Total cartilage and subchondral bone replacement according to claims 1 to 7, characterized in that the contact part (1) is bound to the body of the replacement (2) by means of a shaped mechanical lock (3), which is preferably cylindrical or otherwise a shaped pin (6) and suitable radial shaping by pressing, gluing or otherwise, Total cartilage and subchondral bone replacement according to claim 1, characterized in that the replacement body (2) can be assembled with multiple parts with different material properties similar to the surrounding living tissue, firmly connected in a similar way to contact with each other the part (1) and the body (2). The total replacement of cartilage and subchondral bone according to claim 9, characterized in that the body of the substitute (2) is composed of a polymer material with material properties equal to or close to the surrounding living tissue - subchondral bone, preferably cycloolefin blend. The total replacement of cartilage and subchondral bone according to claims 9 and 10, characterized in that the replacement body (2) consists of a continuous material or a discontinuous material, preferably spongy, Total cartilage and subchondral bone replacement according to claims 9 to 11, characterized in that the replacement body (2) is uncoated at the bottom or is provided with one bore (4) or at least one transverse bore (5) ) for biological fixation in living tissue. Total cartilage and subchondral bone replacement according to claims 9 to 12, characterized in that the replacement body (2) has a smooth or surface-treated surface, preferably with vertical and / or horizontal and / or oblique and / or shape combined grooves.