EP1521558A1

EP1521558A1 - Composite prosthetic implant

Info

Publication number: EP1521558A1
Application number: EP03760056A
Authority: EP
Inventors: Jean-Paul Gilbert Ricol; Richard Jean-Claude Guetty
Original assignee: Compagnie de Recherche en Composants Implants et Materiels pour lApplication Clinique SAS
Current assignee: Compagnie de Recherche en Composants Implants et Materiels pour lApplication Clinique SAS
Priority date: 2002-06-18
Filing date: 2003-06-18
Publication date: 2005-04-13
Also published as: FR2840801A1; AU2003258812A1; BR0312200A; CA2489625A1; WO2003105726A1; FR2840801B1; JP2005534357A; WO2003105726B1; CN1662191A; US20060095139A1; MXPA04012827A; AU2003258812B2

Abstract

The invention relates to a composite prosthetic implant (1), comprising a textile support (2), at least a part of the surface (1A) of which is covered by a lyophilisate (3) of a biocompatible material, characterised in that the lyophilisate (3) is a lyophilisate of a biocompatible material which comprises as principal component one or several of the following substances and/or one or several of the derivatives of the following substances: hyaluronic acid, alginates, polypeptides and polycaprolactones. The invention further relates to surgical prostheses.

Description

COMPOSITE PROSTHETIC IMPLANT

TECHNICAL AREA

The present invention relates to the technical field of prosthetic implants used in particular in the field of parietal surgery.

The present invention relates more particularly to a composite prosthetic implant comprising a textile support associated with a biocompatible material, said implant being intended to be implanted by conventional or ccelioscopic surgery, for example in the treatment of hernias or eventrations.

The present invention also relates to a method of manufacturing a composite prosthetic implant in which a textile support is impregnated with a solution of a first biocompatible material.

PRIOR ART

It is already known to use prosthetic implants to strengthen and repair a damaged muscle wall for example.

Thus, composite prosthetic implants are known comprising a textile network, one of the faces of which is covered with a bioabsorbable film, said film being bonded superficially to the textile network by means of a biocompatible adhesive, or seams, or else by direct impregnation.

Prosthetic implants of the type mentioned above are however of a complex design, which does not, moreover, protect them from delamination phenomena between the tissue and the bioabsorbable film. These implants are also generally relatively heavy, which generates an obvious gene, which in some cases can lead to post-operative complications for the patient.

In addition, the prosthetic implants of the prior art do not allow optimal cellular rehabitation (recolonization).

The complex and multi-layered structure of these implants also requires taking special precautions to avoid any bacteriological development during their manufacture, which generates a complex and expensive manufacturing process, which risks more, by the implementation of drastic measures above, to harm the therapeutic active ingredients that may be contained in the bioabsorbable film.

The placement and positioning of the implants of the prior art are moreover generally delicate and awkward; it is in particular very often difficult for the surgeon to ensure precise positioning of the implant, unless using very traumatic and expensive attachment systems, such as staples.

STATEMENT OF THE INVENTION

The objects assigned to the invention therefore aim to propose a new composite prosthetic implant which does not have the drawbacks of the implants mentioned above, and which is of reduced mass.

Another object of the invention is to propose a new composite prosthetic implant whose mechanical properties are improved. Another object of the invention is to propose a new composite prosthetic implant whose cell rehabitation properties are improved.

Another object of the invention is to propose a new composite prosthetic implant having an improved hemostatic character.

Another object of the invention is to propose a new composite prosthetic implant which may have a bioadhesive character.

Another object of the invention is to propose a new composite prosthetic implant whose therapeutic properties are protected.

Another object of the invention is to propose a new composite prosthetic implant minimizing the risks of post-operative infection.

Another object of the invention is to propose a new method of manufacturing a composite prosthetic implant which is particularly simple and inexpensive to implement.

Another object of the invention is to propose a new method for manufacturing a composite prosthetic implant which is particularly quick to implement.

The objects assigned to the invention are achieved using a composite prosthetic implant comprising a textile support, at least a portion of the surface of which is coated with a lyophilisate of a biocompatible material, characterized in that the lyophilisate is a lyophilizate of a biocompatible material which comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid, - alginates,

- polypeptide,

- polycaprolactone.

The objects assigned to the invention are also achieved using a method of manufacturing a composite prosthetic implant in which a textile support is impregnated with a solution of a first biocompatible material, said method comprising a lyophilization step. said first biocompatible material taking place after the impregnation step, characterized in that the first biocompatible material comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates,

- polypeptide, - polycaprolactone.

SUMMARY OF DRAWINGS

Other objects and advantages of the invention will appear better on reading the attached description, as well as with the aid of the appended drawing, for purely illustrative and informative purposes, in which FIG. 1 illustrates, from a view in side section, the schematic structure of a prosthetic implant according to the invention.

BEST WAY TO IMPLEMENT THE INVENTION Figure 1 shows a composite prosthetic implant 1 according to the invention comprising a textile support 2 and intended to be implanted in the body of a patient, in particular for the treatment of hernias or eventrations.

The term “implant” here designates a prefabricated element intended to be introduced into the body of a patient. In this, an implant, within the meaning of the invention differs in particular from creams or gels intended to be applied during surgical operations.

The term “composite” should be taken here in its most general sense, that is to say that it designates an implant having a substantially heterogeneous structure.

Within the meaning of the invention, a textile support generally designates a structural element involving fibers, and having a discontinuous nature, on the contrary for example a membrane.

Advantageously, said textile support 2 comprises a two-dimensional or three-dimensional structure ply.

This textile sheet can be of any kind, and in particular non-woven, woven, or braided.

Preferably, this textile tablecloth is a warp knitted tablecloth.

The textile support 2 can be obtained from yarns of any kind, and in particular from yarns of biocompatible polymer, absorbable or not.

Preferably, the textile support 2 will be biocompatible but not absorbable. Advantageously, the textile support 2 is obtained from polyester or polypropylene yarns.

These wires can be single-strand or multi-strand.

In a preferred embodiment, a knitted fabric based on multi-strand polyester yarns will be used.

According to the invention, said textile support 2 is associated with a biocompatible material.

By "biocompatible material" is meant here any implantable biomaterial, bioabsorbable or not.

According to the invention, said biocompatible material comprises as main component one or more of the following substances, and / or one or more of the derivatives of the following substances:

- polysaccharide, and in particular preferably: chitosan, hyaluronic acid, alginates, - collagen, bovine or marine, native or not,

- polypeptide, and in particular preferably: polyalpha-amino acid type polypeptide, and even more preferably a copolymer of leucine and methyl glutamate,

- polycaprolactone.

According to an essential characteristic of the invention, at least a portion of the surface 1 A of the textile support 2 is coated with a lyophilisate 3 of the biocompatible material. Lyophilization of the biocompatible material makes it possible to obtain a lyophilisate 3 in the form of a porous material, which lends itself particularly well to cell rehabitation.

In addition, the porous nature of this material makes it a particularly light material, so that a film of conventional biocompatible material, of the membrane type, is substantially ten times heavier than a lyophilisate of the same material, with an equal covering surface. .

The use of a lyophilisate for a prosthetic implant thus makes it possible to obtain a particularly light prosthesis, and therefore easier to support for the patient.

The material (lyophilisate) obtained at the end of the lyophilization also has a spongy character, which gives it good hemostatic properties and promotes possible biological bonding of the implant to biological tissue.

The lyophilization of the biocompatible material also makes it possible to preserve and protect the qualities of the active principles contained in the biocompatible material, and in particular any healing and antibacterial qualities.

Advantageously, the lyophilisate 3 is a lyophilisate of a biocompatible material which comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates, - polypeptide, - polycaprolactone.

In other words, the lyophilisate 3 can comprise only one of the aforementioned four substances (or one of its derivatives), or else a mixture of two, three or four of these substances (or their derivatives). The mixture of derivatives and pure substances is of course also envisaged.

Even more preferably, lyophilisate 3 is a lyophilisate of hyaluronic acid and in particular hyaluronic acid, the molecular weight of which is between 800,000 and 2,000,000 daltons, and even more preferably between 1,200,000 and 1 500,000 daltons.

Preferably, the lyophilisate 3 is intimately linked with the textile support 2, and enters the thickness of the latter, as shown schematically in FIG. 1.

The textile support 2 and the lyophilisate 3 thus form a coherent material, the components of which (textile support and lyophilisate) are substantially inseparable.

Such an integrated structure is particularly advantageous from the point of view of the mechanical properties of the prosthetic implant according to the invention, since it makes it possible to reduce the risks of delamination between the textile support and the biocompatible material.

The prosthetic implant 1 according to the invention is thus preferably formed by a textile substrate 2 forming a first layer, this first layer 2 comprising a first and a second opposite face 1A, 1 B. The first face 1A of the first layer 2 is itself covered, preferably entirely, by a second layer 3 formed by the lyophilisate 3. In another embodiment, the two faces 1 A, 1 B of the substrate 2 are covered respectively by a second and a third layer of lyophilisate, said two layers of lyophilisate possibly being of identical or different natures, in terms of thickness or composition in particular.

The prosthetic implant 1 according to the invention is thus in the form of a multilayer complex associating a series of superimposed layers 2, 3, and secured to one another, preferably over their entire contact surface.

In the case where the lyophilisate 3 is produced from hyaluronic acid, this lyophilisate 3 is in the form of a layer of foam having a relatively dry and non-sticky feel. When this layer of foam is moistened with liquid, the said layer then becomes sticky, which allows the surgeon, in particular in the case of hernia treatments or eventrations, to stick the implant to the parietal tissues, without using invasive means or traumatic such as staples or sutures. This activatable sticky nature is particularly effective in the case of a lyophilisate 3 produced exclusively from hyaluronic acid. However, this character is no less present in the case where other materials are used, for example sodium alginate or chitosan.

Advantageously, a lyophilizate 3 having a bioresorbable nature will be produced.

The invention also relates to a method of manufacturing a composite prosthetic implant according to the invention.

In this process, a textile support 2 is impregnated with a solution of a first biocompatible material. This impregnation can for example be carried out by dipping. By "solution" is meant a substance whose viscosity and wettability characteristics are compatible with an operation of the coating or impregnation type, unlike a substance in the solid state.

According to an important characteristic of the manufacturing method according to the invention, said method comprises a step of lyophilization of said first biocompatible material, said step of lyophilization taking place after the aforementioned impregnation step.

Thus, the method according to the invention makes it possible to obtain a lyophilisate 3 on the surface of the textile support 2, said lyophilisate 3 coming substantially from the material with the impregnated textile support.

According to the invention, the first biocompatible material comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid, - alginates,

- polypeptide,

- polycaprolactone.

It is particularly interesting to note that lyophilization can be schematically assimilated to pre-sterilization, in the sense that it minimizes bacteriological development, and in particular for example the development of salmonella.

Thus, the manufacturing process according to the invention is particularly safe from the point of view of the bacteriological risk. Advantageously, the method according to the invention comprises, after the aforementioned impregnation step and before the lyophilization step, a pouring step, in which a solution of a second biocompatible material is poured onto the textile support. prepreg. The second biocompatible material preferably comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates, - polypeptide,

- polycaprolactone.

In a particular embodiment, the second material is similar to the first material.

The solution of second biocompatible material also subsequently undergoes freeze-drying, during the freeze-drying step.

Advantageously, the process according to the invention comprises, after the impregnation step and before the lyophilization step, a coating step in which the textile support impregnated is coated with a layer of a solution of 'a third biocompatible material.

The third biocompatible material preferably comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates, - polypeptide,

- polycaprolactone.

In a particular embodiment, the third material is similar to the first material and / or to the second material.

The solution of third biocompatible material then also undergoes lyophilization, during the lyophilization step.

The aforementioned pouring and coating steps fall under a similar approach, with the difference that we will opt for pouring, as regards a low viscosity solution, and for coating as regards a solution higher viscosity.

Advantageously, the method according to the invention comprises a spreading step, in which a layer of a solution of a fourth biocompatible material is spread over the tray of the lyophilizer used in the lyophilization step, and then placed against this layer the textile support 2 impregnated with the solution of the first biocompatible material.

The fourth biocompatible material preferably comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid, - alginates,

- polypeptide,

- polycaprolactone. In a particular embodiment, the fourth biocompatible material is similar to the first material and / or to the second material, and / or to the third material.

The solution of fourth biocompatible material then also undergoes freeze-drying, during the freeze-drying step.

Advantageously, the manufacturing method according to the invention comprises a step of drying the impregnated textile support, said drying step taking place consecutively to the impregnation step.

It is therefore understood that the invention generally resides in the implementation of a lyophilisate 3 on the surface of a textile support, with a view to the production of surgical prostheses, regardless of the numerous methods of implementation. of this concept, which are evident from reading this description for those skilled in the art.

The prosthetic implant according to the invention therefore has high mechanical properties, both from the point of view of resistance and resistance as well as flexibility, which is particularly sought after in laparoscopic applications (passage through a trocar). This flexibility proceeds in particular on the one hand from the spongy nature of the lyophilisate 3, which does not have a fragile intrinsic character and is less subject to breaks or tears than the films of the prior art, and on the other hand to the intimate connection between the lyophilisate 3 and the textile support 2.

Preferably, the implant 1 according to the invention is sterilized, for example by gamma rays.

We will now describe some examples of embodiments of prosthetic implants according to the invention. Example 1

A 1% solution of hyaluronic acid with a molecular mass of approximately 800,000 daltons is prepared by hydration of sodium hyaluronate in sterile water for injection (purified water).

The previously obtained solution is poured into a beaker, in which a prosthetic fabric made from knitted multi-strand polyester (PES) yarns is then placed.

The tissue is left in the beaker for fifteen to thirty minutes, so that its fibers are well impregnated with hyaluronic acid.

The tissue thus impregnated is then placed on the tray of a lyophilizer, and a little of the hyaluronic acid solution is poured onto the impregnated tissue.

The tray is then placed in freezing at -40 ° C for three hours. Sublimation is then carried out from -40 ° C to + 30 ° C to 0.25 millibars for 18 h 30, then desorption at 30 ° C and 0.03 millibars for 7 hours. This gives a prosthetic implant formed from a tissue whose pores are blocked by the lyophilisate.

Example 2

A first homogeneous solution containing 1% of hyaluronic acid of molecular mass approximately equal to 800,000 daltons is prepared by hydration of sodium halyuronate in sterile water for injection. A second 2% solution of hyaluronic acid of molecular mass approximately equal to 800,000 daltons is then prepared by hydration of sodium halyuronate in sterile water for injection.

The first solution is poured into a beaker, into which a fabric made from knitted multi-strand polyester (PES) yarns is then placed.

The tissue is left in the beaker for 15 to 30 minutes so that its fibers are well impregnated with hyaluronic acid.

Using a spatula, a layer of the second solution is then spread over the tray of a lyophilizer, so that this layer has a thickness of approximately 3 mm. The pre-impregnated and drained fabric is then placed on this layer of the second solution. Then spreading a second layer, substantially similar to the first layer, on the fabric, on the face opposite to that in contact with the first layer.

The tray is then placed in freezing at -40 ° C for 3 hours. Sublimation is then carried out from -40 ° C to + 30 ° C to 0.25 millibars for 18 h 30, then desorption at 30 ° C and 0.03 millibars for 7 hours.

This gives a prosthesis coated with lyophilisate on both sides. The areal mass of the lyophilizate of hyaluronic acid is approximately 1 g per 100 cm ² .

As a variant, the fabric impregnated with the first solution is allowed to dry before coating it with the second solution.

Example 3 A first homogeneous solution containing 0.7% of hyaluronic acid of molecular mass approximately equal to 1,570,000 daltons is prepared by hydration of sodium hyaluronate in sterile water for injection.

A second homogeneous solution containing 1.5% of hyaluronic acid of molecular mass approximately equal to 1,570,000 daltons is prepared by hydration of sodium hyaluronate in sterile water for injection.

The first solution is poured into a beaker, into which a prosthetic fabric made from knitted multi-strand polyester (PES) yarns is then placed. The tissue is kept for 15 to 30 minutes in the beaker, so that its fibers are well impregnated with hyaluronic acid.

The impregnated fabric, which has been previously drained, is then placed on the tray of a freeze dryer. Then spread, using a spatula, a layer of the second solution with a thickness of approximately 3 mm.

The tray is then placed at - 80 ° C for one hour, then at - 40 ° C for 2 hours. Sublimation is then carried out from -40 ° C to + 50 ° C to 0.25 millibars for 12 hours and then desorption at 60 ° C and 0.03 millibars for 7 hours.

An implant is obtained, one of the faces of which is coated with lyophilized hyaluronic acid. The surface mass of the lyophilisate of hyaluronic acid is approximately equal to 0.5 g per 100 cm ² .

As a variant, only part of one of the faces of the fabric is coated with a layer of approximately 3 mm in thickness of the second solution, the rest of this face being masked by a silicone template. The template is removed between the first freezing step at - 80 ° C for 1 hour and the second freezing step at - 40 ° C for 2 hours. The cycle of lyophilization described above is then continued. According to this variant, an implant is thus obtained, of which only part of one of the faces is covered with lyophilized hyaluronic acid.

Example 4

A 1% solution of sodium alginate in water for injection is prepared (purified water).

A fabric made from multi-strand polyester yarns knitted with the previous solution is impregnated, then the fabric is placed on the tray of a freeze-dryer and coated with the previously made solution.

The tray is then placed in freezing at -40 ° C for three hours.

Sublimation is then carried out from -40 ° C to + 30 ° C to 0.25 millibars for 18 h 30, then desorption at 30 ° C and 0.03 millibars for 7 hours. A tissue implant is obtained, the pores of which are blocked with lyophilisate.

Example 5

A 1% chitosan solution in water for injection is produced with 30 drops of acetic acid.

A fabric made from multi-strand polyester (PES) yarns knitted with this solution is impregnated. The impregnated fabric is placed on the tray of a freeze dryer, and it is coated with the previous solution. The tray is then placed in freezing at -40 ° C for 3 hours, then sublimation is carried out from -40 ° C to + 30 ° C to 0.25 millibars for 18 h 30, finally the desorption is carried out at 30 ° C and 0.03 millibars for 7 hours. We obtains a tissue in which the pores are blocked with the lyophilisate. The lyophilisate has a substantially yellow color and its resistance to the fabric is less than that of the lyophilisates of hyaluronic acid of the previous examples.

POSSIBILITY OF INDUSTRIAL APPLICATION

The invention finds its industrial application in the manufacture and use of surgical implants.

Claims

- Composite prosthetic implant (1) comprising a textile support (2) of which at least a portion of the surface (1A) is coated with a lyophilisate (3) of a biocompatible material, characterized in that the lyophilisate (3) is a lyophilizate of a biocompatible material which comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates, - polypeptide,

- polycaprolactone.

- Implant according to claim 1 characterized in that the lyophilisate (3) is a lyophilisate of hyaluronic acid with a molecular mass of between 800,000 and 2,000,000 daltons, and preferably between 1,200,000 and 1,500,000 daltons.

- composite prosthetic implant (1) according to claim 1 or 2 characterized in that said textile support (2) comprises a two-dimensional or three-dimensional structure ply selected from the following group: - non-woven ply,

- woven tablecloth,

- knitted tablecloth,

- braided tablecloth. - Composite prosthetic implant (1) according to claim 1 to 3 characterized in that said textile support (2) is obtained from son chosen from the following group:

- single-strand or multi-strand polyester yarns, - single-strand or multi-strand polypropylene yarns.

- Implant (1) according to one of the preceding claims, characterized in that it forms a prosthesis for hernia repair or eventration.

- Method for manufacturing a composite prosthetic implant (1) in which a textile support (2) is impregnated with a solution of a first biocompatible material, said method comprising a step of lyophilization of said first biocompatible material taking place after the step impregnation, characterized in that the first biocompatible material comprises, as main component, one or more of the following substances, and / or one or more of the derivatives of the following substances:

- hyaluronic acid,

- alginates,

- polypeptide,

- polycaprolactone.

- Method according to claim 6 characterized in that it comprises, after the impregnation step and prior to the lyophilization step, a pouring step, in which a solution of a second biocompatible material is poured onto the impregnated textile support. - Method according to claim 6 characterized in that it comprises, after the impregnation step and prior to the lyophilization step, a coating step in which the textile support impregnated with a layer of a solution of a third biocompatible material.

- Method according to one of claims 6 to 8, characterized in that it comprises a spreading step, in which is spread on the tray of the lyophilizer used in the lyophilization step a layer of a solution of a fourth biocompatible material, then the textile support (2) impregnated with the solution of the first biocompatible material is placed against this layer.

-A method according to one of claims 6 to 9 characterized in that it comprises a step of drying the impregnated textile support taking place consecutively to the impregnation step.