Surgical Implant

Abstract

A surgical implant (1) comprises a flexible, areal basic structure (2) having a first face (3) and a second face (4) and being provided with pores (6) extending from the first face (3) to the second face (4). An absorbable film layer (10) is placed at the first face (3) of the basic structure (2), is attached to the basic structure (2) and has an outer face (12) facing away from the basic structure (2). An absorbable marker (20) is attached to the outer face (12) of the film layer (10), wherein the marker (20) is adapted to indicate an upside/downside orientation of the outer face (12) of the film layer (10) and to indicate a center area of the basic structure (2).

Claims

1. A surgical implant, comprising a flexible, areal basic structure having a first face and a second face and being provided with pores extending from the first face to the second face, and an absorbable film layer placed at the first face of the basic structure, being attached to the basic structure and having an outer face facing away from the basic structure, characterized by an absorbable marker attached to the outer face of the film layer, wherein the marker is adapted to indicate an upside/downside orientation of the outer face of the film layer and to indicate a center area of the basic structure.

2. A surgical implant according to claim 1, characterized in that the marker is adapted to indicate a direction.

3. A surgical implant according to claim 1, characterized in that the marker lacks mirror symmetry about a mirror axis lying in a plane defined by the outer face of the film layer.

4. A surgical implant according to any one of claim 1, characterized in that the marker comprises at least one of the following elements: string of characters logo, direction-indicating line, center-indicating marking.

5. A surgical implant according to any one of claim 1, characterized in that the film layer is transparent.

6. A surgical implant according to claim 5, characterized in that the marker is adapted to appear at different contrasts and/or intensities when viewed either from the side of the outer face of the film layer or from the opposite side.

7. A surgical implant according to any one of claim 1, characterized in that the marker comprises at least one of the following features: being positioned in a center area of the basic structure, having a prominent element in a center area of the basic structure, indicating a symmetry axis of the basic structure, indicating a pre-determined direction depending on mechanical properties of the basic structure, being continuous, being non-continuous, being palpable, having rounded edge zones, having a lusterless surface, having a textured surface, being fully laminated to the film layer, being partially laminated to the film layer, being thicker than the film layer, being thicker than the film layer by a factor of at least 5, being thicker than the film layer by a factor of at least 10, having an edge angle to the film layer of less than 90 degrees, having an edge angle to the film layer of less than 75 degrees, having an edge angle to the film layer of less than 60 degrees, at least partially being generally flat, entering pores provided in the film layer at least partially following a topography determined by the film layer.

8. A surgical implant according to any one of claim 1, characterized in that the marker comprises at least one of the following features: containing a polymer, being derived from a polymer film, comprising absorbable film material, having a melting temperature which is lower than the melting temperature of the film layer, having anti-adhesive properties with respect to biological structures, being colored, being colored and de-coloring in mammalian tissue in less than 30 days.

9. A surgical implant according to any one of claim 1, characterized in that the marker is applied to the outer face of the film layer by using a printing or spraying technique.

10. A surgical implant according to any one of claim 1, characterized in that the film layer is deformed into at least part of the pores of the basic structure where it forms, in a respective pore, a film region close to the level of the second face of the basic structure.

11. A surgical implant according to any one of claim 1, characterized in that the film layer comprises one of the features in each one of the following sets of contrasting features: being non-porous, having pores; being generally flat, being deformed into at least part of the pores of the basic structure; being continuous, being made of a plurality of spaced film pieces.

12. A surgical implant according to any one of claim 1, characterized in that the film layer comprises pores, wherein material of the marker penetrates at least part of the pores and is connected to the basic structure.

13. A surgical implant according to any one of claim 1, characterized in that the basic structure comprises at least one of the following features: comprising perforated film material, comprising a surgical mesh, being at least partially translucent, having anisotropic stretching properties.

14. A surgical implant according to any one of claim 1, characterized in that the basic structure comprises a non-absorbable material, preferably at least one of the materials selected from the following list: polyalkenes, polypropylene, polyethylene, fluorinated polyolefins, polytetrafluoroethylene, PTFE, ePTFE, cPTFE, polyvinylidene fluoride, blends of polyvinylidene fluoride and copolymers of vinylidene fluoride and hexafluoropropene, polyamides, polyimides, polyurethanes, polyisoprenes, polystyrenes, polysilicones, polycarbonates, polyarylether ketones, polymethacrylic acid esters, polyacrylic acid esters, aliphatic polyesters, aromatic polyesters, copolymers of polymerizable substances thereof.

15. A surgical implant according to any one of claim 1, characterized in that the basic structure comprises an absorbable material, preferably at least one of the materials selected from the following list: synthetic bioabsorbable polymer materials, polyhydroxy acids, polylactides, polyglycolides, copolymers of glycolide and lactide, copolymers of glycolide and lactide in the ratio 90:10, copolymers of glycolide and lactide in the ratio 5:95, copolymers of lactide and trimethylene carbonate, copolymers of glycolide, lactide and trimethylene carbonate, polyhydroxybutyrates, polyhydroxyvaleriates, polycaprolactones, copolymers of glycolide and -caprolactone, polydioxanones, poly-p-dioxanone, synthetic and natural oligo- and polyamino acids, polyphosphazenes, polyanhydrides, polyorthoesters, polyphosphates, polyphosphonates, polyalcohols, polysaccharides, polyethers, collagen, gelatin, bioabsorbable gel films cross-linked with omega 3 fatty acids, oxygenized regenerated cellulose.

16. A surgical implant according to any one of claim 1, characterized in that the film layer comprises at least one of the materials selected from the following list: copolymers of glycolide and -caprolactone, collagens, gelatine, hyaluronic acid, polyvinyl pyrrolidone, polyvinyl alcohol, fatty acids, polyhydroxy acids, polyether esters, polydioxanones, copolymers of polymerizable substances thereof.

17. A surgical implant according to any one of claim 1, characterized in that the marker comprises at least one of the materials selected from the following list: poly-p-dioxanone, dyed poly-p-dioxanone, poly-p-dioxanone dyed with a violet dye.

18. A process of manufacturing a surgical implant according to claim 1, characterized by the steps: providing a flexible, areal basic structure having a first face and a second face and being provided with pores extending from the first face to the second face, providing an absorbable film layer, placing the film layer onto the first face of the basic structure, an outer face of the film layer facing away from the basic structure, applying heat and pressure, thereby softening a material provided at at least one of the basic structure and the film layer and attaching the film layer to the basic structure, providing an absorbable marker which is adapted to indicate an upside/downside orientation of the outer face of the film layer and to indicate a center area of the basic structure, placing the marker on the outer face of the film layer, applying heat and pressure, thereby softening a material provided at at least one of the film layer and the marker and attaching the marker to the film layer.

19. A process according to claim 18, characterized in that at least one of the basic structure and the film layer comprises a bonding material, which has a melting temperature lower than the melting temperature of at least part of the material of the basic structure and lower than the melting temperature of at least part of the material of the film layer wherein the bonding material preferably comprises poly-p-dioxanone.

20. A process according to claim 18, characterized in that the marker comprises poly-p-dioxanone and is attached to the film layer, after the film layer has been attached to the basic structure, by applying heat and pressure for a period of time short enough in order to avoid deterioration of the marker, the film layer and the basic structure.

21. A process of intraperitoneally placing a surgical implant according to any one of claim 1 in a patient's body, comprising the steps: introducing the surgical implant via a trocar sleeve into the body and deploying the surgical implant, thereby using the marker to ensure that the second face of the basic structure faces the peritoneum, fixing the implant on the peritoneum.

22. A process according to claim 21, wherein the implant, with the second face of the basic structure, is stuck on the peritoneum before the implant is fixed on the peritoneum.

Description

[0056] In the following, the invention is further described by means of embodiments. The drawings show in

[0057] FIG. 1 a three-dimensional view of an embodiment of a surgical implant according to the invention, which is partially cut away, including a first embodiment of a marker,

[0058] FIG. 2 in part (a) a second embodiment of a marker in plane view, in part (b) the second embodiment of a marker in three-dimensional view, and in part (c) a third embodiment of a marker in three-dimensional view, and

[0059] FIG. 3 a fourth embodiment of a marker in plane view.

[0060] FIG. 1 illustrates an embodiment of a surgical implant, designated by 1, in a three-dimensional view. The surgical implant 1 comprises a basic structure 2 having a first face 3 and a second face 4. In the view according to FIG. 1, the first face 3 points upwardly and the second face 4 points downwardly. The basic structure 2 includes pores 6 extending from the first face 3 to the second face 4. In the embodiment, the basic structure 2 is designed as a surgical mesh warp-knitted from polypropylene monofilament fibers (non-absorbable) and poly-p-dioxanone (PDS; Ethicon) monofilament fibers (absorbable).

[0061] A film layer 10 is placed at the first face 3 of the basic structure 2 and attached to the basic structure 2. An outer face 12 of the film layer 10 faces away from the basic structure 2. In the embodiment, the film layer 10 is approximately 10 m thick, transparent and made of MONOCRYL, an absorbable copolymer of glycolide and s-caprolactone (polyglecaprone 25 suture polymer or MONOCRYL, Ethicon). The film layer 10 serves as a barrier layer and has anti-adhesive properties. In FIG. 1, the film layer 10 is removed in one corner of the surgical implant 1 to exhibit the basic structure 2.

[0062] An absorbable marker 20 is attached to the outer face 12 of the film layer 10. In the embodiment, the marker 20 is made from laser-cut film material (thickness about 100 m) of PDS (absorbable) dyed with the biocompatible violet dye D&C Violet No. 2.

[0063] The marker 20 is a first embodiment of a marker. It comprises a string 22 of characters, forming the word viscera, and an interrupted line 24. When the surgical implant 1 is oriented as shown in FIG. 1, the marker 20 is at its upper side, and viscera can be easily read. However, if the surgical implant 1 is oriented upside down, the word viscera will appear in mirror-writing, thus clearly indicating the different upside/downside orientation. The interrupted line 24 may serve as an indicator of a direction, e.g. for an axis of the surgical implant 1 where the elastic properties behave in a particular way or simply as an indicator for the long side of the rectangular shape of the surgical implant 1. Moreover, the gap in the interrupted line 24 as well as the letters ce indicate the center area of the surgical implant 1.

[0064] FIG. 2(a) shows a second embodiment of a marker, designated by 30. The marker 30 consists of the word visceral only, which is able to indicate the correct upside/downside orientation of the surgical implant (mirror-writing or not), its center area (letters ce) and an orientation (direction of writing). The three-dimensional view of the marker 30 in FIG. 2(b) illustrates that the letters of visceral have relatively sharp edges. A similar marker 32, shown as a third embodiment in FIG. 2(c), is made of letters comprising roundish edges, which may improve palpability.

[0065] A fourth embodiment of a marker, designated by 40, is displayed in FIG. 3 in plane view. The marker 40 is more elaborate and, in contrast to the markers 20, 30 and 32, made in one piece. It comprises a string 42 of characters to indicate the upside/downside orientation, a line 44 with an arrow 45 to indicate a direction, and a particular center marking 46.

[0066] Generally, markers having the desired properties can be designed in multiple ways.

[0067] The following example describes the manufacture of an embodiment of the surgical implant according to the invention.

EXAMPLE 1

[0068] A composite surgical mesh, comprising non-absorbable monofilament polypropylene and dyed absorbable monofilament PDS fibers and serving as a basic structure, was heat-laminated with a 10-m MONOCRYL film (serving as an adhesion barrier layer) in a lamination press, wherein the PDS fibers acted as a melt glue. After cooling down under pressure, a 150-m PDS film dyed with D&C Violet No. 2 (serving as a marker) was placed on top of the MONOCRYL film, covered with a rough baking paper and laminated (for some seconds, at about 110 C., and at a low pressure of 1-5 bar), wherein the pressing period was shorter than in the first lamination step. The marker was firmly attached to the underlying MONOCRYL film of the surgical implant manufactured in this way. Under the microscope, the surface of the marker showed a micro-roughness (due to the rough baking paper) with tiny lines in multiple directions having a width of less than 20 m.

[0069] In an intraperitoneal pig handling study, this surgical implant was easily passed through a trocar sleeve and placed at the abdominal wall. It showed a clinging effect, and the absorbable marker indicated the correct north-south direction and additionally the visceral side. The visibility of the marker was intense when the surgical implant was correctly positioned. A wrong upside/downside orientation strongly reduced the intense visibility impression of the marker, thus providing an additional orientation means.

EXAMPLE 2

[0070] Samples of surgical implants were prepared according to Example 1, each one having a rectangular size of 3 cm5 cm with slightly rounded edges and having one additional round dyed PDS disk film (thickness about 150 m) centrally laminated on the outer face of the MONOCRYL film.

[0071] A rabbit peritoneal defect model was used, as described elsewhere (U.S. Pat. No. 8,629,314 B). Adhesions where evaluated after 2 weeks, see Table 1.

[0072] When a respective implant was correctly placed, with the mesh side to the abdominal wall and the film side to the viscera, almost no adhesions occurred. Only one implantation site (out of eight) showed minor grade 1 adhesion (12.5% incidence), the remaining test samples were free of adhesion. However, when the implant was wrongly positioned with the mesh side facing to the viscera, in 87.5% of the cases adhesion occurred, generally more severe with grades from 1 to 4.

[0073] Surprisingly, the inventive surgical implants with the film side and the marker facing to the viscera exhibited a good adhesion reduction. After explantation, the marker polymer was still present, but its color had completely leached of, making the marker almost invisible.

TABLE-US-00001 TABLE 1 In-vivo performance (rabbit, sidewall model) Treatment Groups (n = 8) Adhesion Incidence Adhesion Extent Sham Control 8/8 (100%) Grade 1 (2/8) Grade 2 (4/8) Grade 3 (1/8) Grade 4 (1/8) Example 2 (film side 1/8 (12.5%) Grade 0 (7/8) to viscera) Grade 1 (1/8) Example 2 (mesh side 7/8 (87.5%) Grade 0 (1/8) to viscera) Grade 1 (3/8) Grade 2 (2/8) Grade 4 (2/8)