Prosthesis Comprising a Three-Dimensional and Openworked Knit

Abstract

The present invention relates to a prosthesis (100) comprising an openworked three-dimensional knit (101) comprising a front face and a rear face, each face being formed with one or more laps of yarns defining pores on said face, the front face being bound to the rear face by connecting yarns defining a spacer, characterized in that the connecting yarns are distributed so that they define an entanglement of yarns crossing each other at the spacer, without obstructing the pores of the front and rear faces.

Claims

1-24. (canceled)

25. A prosthesis comprising at least one openworked three-dimensional knit including two opposite faces, a front face and a rear face, each front and rear face being formed with one or several laps of yarns defining pores on said front and rear faces, said front face being bound to said rear face by connecting yarns defining a spacer, wherein the connecting yarns are distributed so that said connecting yarns define a crisscrossing set of yarns crossing each other at the spacer, without obstructing the pores of the two opposite faces, wherein the front face includes r rows and n columns of stitches facing r′ rows and n′ columns of stitches of the rear face, with at least one portion of the connecting yarns connecting a column n.sub.i of the n columns of stitches of the front face to a column (n.sub.i′+x) of n′ columns of stitches of the rear face, wherein x ranges from 2 to 5, and connecting a column n.sub.j of the n columns of stitches of the front face to a column (n.sub.j′−x′) of n′ columns of stitches of the rear face, wherein x′ ranges from 2 to 5.

26. The prosthesis of claim 25, wherein x=x′.

27. The prosthesis of claim 25, wherein x=x′=2.

28. The prosthesis of claim 25, wherein x=x′=3.

29. The prosthesis of claim 25, wherein x=x′=4.

30. The prosthesis of claim 25, wherein x is different from x′.

31. The prosthesis of claim 25, wherein the spacer has an X-profile.

32. The prosthesis of claim 25, wherein the rear face includes an additional textile layer attached thereto.

33. The prosthesis of claim 32, wherein the additional textile layer is configured to promote cell colonization into the rear face of the knit.

34. The prosthesis of claim 33, wherein the additional textile layer is a skirt including a central aperture.

35. The prosthesis of claim 25, wherein the front face includes an anti-adhesion coating thereon.

36. The prosthesis of claim 35, wherein the anti-adhesion coating is bioresorbable.

37. The prosthesis of claim 36, wherein the anti-adhesion coating is in the form of a bioresorbable textile.

38. The prosthesis of claim 37, wherein the bioresorbable textile includes oxidized cellulose.

39. The prosthesis of claim 36, wherein the anti-adhesion coating is in the form of a bioresorbable film.

40. The prosthesis of claim 36, wherein the anti-adhesion coating is a film including one or more of collagen, glycerol or chitosan.

41. The prosthesis of claim 32, wherein the openworked three-dimensional knit is in the form of a continuous part having a periphery, the additional textile layer being provided with a central aperture, and the front face covered with an anti-adhesion coating.

42. The prosthesis of claim 25, wherein the pores of the front face and the pores of the rear face are substantially aligned on each other providing the knit with transparence.

43. The prosthesis of claim 42, wherein the pores of the front face and the pores of the rear face remain in the same relative position when the knit is subject to compressive forces thereby maintaining the transparence of the knit.

44. The prosthesis of claim 25, wherein the connecting yarns define in addition a set of parallel or oblique yarns not crossing each other and not obstructing the pores of the two opposite faces.

Description

[0071] The invention will be better understood from the detailed description and the examples which follow, as well as with the figures wherein:

[0072] FIG. 1 is a view of the weave of a knit of a prosthesis according to the invention,

[0073] FIG. 2 is a view of the weave of a knit of another embodiment of a prosthesis according to the invention,

[0074] FIG. 3 is a scanning electron microscope view of one face of the knit obtained with the weave of FIG. 1,

[0075] FIG. 4 is a top view of an embodiment of a prosthesis according to the invention,

[0076] FIG. 5 is a top view of another embodiment of a prosthesis according to the invention,

[0077] FIG. 6 is a view of the weave of a knit of another embodiment of a prosthesis according to the invention,

[0078] FIG. 7 is a scanning electron microscope view of one face of the knit obtained with the weave of FIG. 6.

[0079] With reference to FIG. 4, a prosthesis 100 according to the invention is illustrated, comprising an openworked three-dimensional knit 101 comprising a front face 102 and a rear face (not visible in the figure): this knit 101 may be produced according to Example 1 below or according to Example 2 or according to Example 3 below. Thus, each face of the knit 101 is formed with one or more laps of yarns defining pores on said face, a face being bound to the opposite face by connecting yarns defining a spacer, the connecting yarns are distributed so that they define an entanglement of yarns which cross each other at the spacer, without obstructing the pores of the two opposite faces.

[0080] In the illustrated example, the knit 101 is in the form of a round part and has a circular periphery 101a. The prosthesis 100 further comprises a textile layer 103, having a periphery 103a substantially identical with that of the knit 101. The textile layer 103 is attached through its periphery 103a to the periphery 101a of the knit 101, and it has a central aperture 104: the textile layer 103 thereby forms a free skirt 105. During the implantation of the prosthesis 100 at a defect of the abdominal wall, for example in the treatment of a hernia, the surgeon may suture this free skirt 105 to the abdominal wall in order to effectively attach the prosthesis 100.

[0081] The prosthesis 100 further comprises an anti-adhesion coating in the form of a film 106 covering the rear face of the knit 101. In the illustrated example, the film 106 slightly juts out from the peripheries (101a, 103a) of the knit 101 and of the textile layer 103. Preferably, the film is obtained from a mixture of oxidized collagen and glycerol as described in U.S. Pat. Nos. 6,451,032, 6,165,488 and 6,391,939.

[0082] Such a film 106 prevents the formation of post-surgical fibrous adhesions.

[0083] By the properties of the three-dimensional knit as mentioned in Examples 1, 2 and 3 below, the prosthesis according to the invention as described in FIG. 4 has excellent three-dimensional stability and therefore a good capability for cell recolonization, even when the prosthesis is subject to pressure forces tending to press both faces against each other, as this may be accomplished by abdominal pressure. The prosthesis according to the invention also has excellent resistance to suture.

[0084] In FIG. 5, for which the references designating the same elements as for FIG. 4 have been retained, is illustrated a prosthesis 100 similar to the one of FIG. 4, but the openworked three-dimensional knit 101 has the shape of a globally rectangular part.

[0085] The present application also describes a method for treating hernia consisting of providing a prosthesis according to the invention and of implanting it at the hernial defect: for example the face of the knit covered with the anti-adhesion coating is placed facing the abdominal cavity while the non-covered face, either provided or not with an additional textile layer forming a skirt, is placed facing the abdominal wall, with view to cell recolonization. When the prosthesis comprises a skirt as described above, the surgeon may directly attach the skirt of the prosthesis to the abdominal wall by means of sutures or clamps.

EXAMPLE 1

[0086] A knit suitable for the prosthesis according to the invention is produced with 50 decitex multi-filament polyester yarns, number of filaments per yarn:22.

[0087] The knit is produced on a two-bed Rachel knitting machine with 6 threaded guide bars 1 full stitch, 1 empty stitch, according to the following weave according to the ISO 11676 standard:

[0088] BAV1: 1.0.1.1/1.2.1.1/1.0.1.1/2.3.2.2/2.1.2.2/2.3.3.3/4.5.4.4/4.3.4.4/4.5.4.4/3.2.3.3/3.4.3.3/3.2.2.2//

[0089] BAV2: 4.5.4.4/4.3.4.4/4.5.4.4/3.2.3.3/3.4.3.3/3.2.2.2/1.0.1.1/1.2.1.1/1.0.1.1/2.3.2.2/2.1.2.2/2.3.3.3//

[0090] BE1: 1.1.1.0/1.0.1.0/1.0.1.1/1.1.1.0/2.3.2.3/2.3.2.2/2.2.2.3/2.3.2.3/2.3.2.2/2.2.2.3/1.0.1.0/1.0.1.1//

[0091] BE2: 2.2.2.3/2.3.2.3/2.3.2.2/2.2.2.3/1.0.1.0/1.0.1.1/1.1.1.0/1.0.1.0/1.0.1.1/1.1.1.0/2.3.2.3/2.3.2.2//

[0092] BAR1: 2.2.1.0/1.1.1.2/1.1.1.0/1.1.2.3/2.2.2.1/2.2.2.3/3.3.4.5/4.4.4.3/4.4.4.5/4.4.3.2/3.3.3.4/3.3.3.2//

[0093] BAR2: 3.3.4.5/4.4.4.3/4.4.4.5/4.4.3.2/3.3.3.4/3.3.3.2/2.2.1.0/1.1.1.2/1.1.1.0/1.1.2.3/2.2.2.1/2.2.2.3//

[0094] This weave is illustrated in FIG. 1, in which the bars BAV1, BAV2, BE1, BE2, BAR1 and BAR2, are indicated with for each bar the path of a yarn (indicated in solid lines). In this figure, the numbers 1, 2, 3, . . . 12 indicate the rows of stitches of the front face; the numbers 1′, 2′, 3′, . . . , 12′ indicate the rows of stitches of the rear face. Also in this figure, a vertical sequence of points represents two columns of stitches, both front and rear, facing each other. In FIG. 1, the columns are indicated as n, n′, (n+1), (n′+1), (n+2) and (n′+2).

[0095] In the present example the yarns of the BAV1 and BAV2 bars form the front face, the yarns of the BE1 and BE2 bars form the spacer and the yarns of the BAR1 and BAR2 bars form the rear face. In the present example, the connecting yarns are therefore yarns from laps dedicated to the formation of the spacer, i.e. the laps obtained with the BE1 and BE2 bars.

[0096] The weave followed for the front face produces a front face comprising pores. Also, the weave followed for the rear face produces a face comprising pores. The pores of the front face are substantially facing the pores of the rear face.

[0097] As this appears in FIG. 1, the yarn of the BE1 bar, at the row 4′ and at the column n′ of the rear face, does not connect column n of the 5.sup.th row of the front face, but it connects column (n+2). By doing this, it connects the rear face to the front face obliquely and not perpendicularly to these faces. Next, this yarn at the row 10′ of the rear face, connects column (n′+2) to column n at the 11.sup.th row of the front face. In the present example, x and x′ as defined in the present application are therefore each equal to 2.

[0098] The yarn of the BE2 bar is also involved in the formation of the spacer, symmetrically to the yarn of the BE1 bar.

[0099] Thus, the spacer obtained is formed with connecting yarns which regularly cross each other.

[0100] The thereby obtained spacer is particularly resistant to compressive forces tending to press the front face onto the rear face. Subject to such forces, the spacer does neither collapse nor lie down thereby retaining its three-dimensional structure to the knit.

[0101] The obtained knit has the following properties:

[0102] 1°) Thickness: 1.7 mm

[0103] By its structure, the knit of the present example substantially retains its height even when it is subject to a compressive force tending to press its front face onto the rear face.

[0104] 2°) Transparence and Size of the Pores for Both Front and Rear Faces: [0105] small pores (width×height): 2.0×2.4 mm [0106] large pores (width×height): 2.1×2.5 mm

[0107] By the structure of the knit of the present example, the pores of the front face remain facing the pores of the rear face, even when the knit is subject to a compressive force tending to compress its front face onto its rear face.

[0108] FIG. 3 is a view taken with a scanning electron microscope of one face of the knit of the present example. As this is apparent from this view, the pores of the front face are distinctly seen (the closest to the apparatus taking the photograph) and it is also possible to distinguish in the background the pores of the rear face: the pores of the front face and those of the rear face are facing each other. Thus, the knit has excellent transparence which allows the surgeon to handle a prosthesis comprising such a knit with facility and to easily position it, in particular with respect to the surrounding organs. Indeed, the knit of the prosthesis allows the surgeon to have good visibility in transparence of the surrounding organs.

[0109] 3°) Suture strength, as measured according to the NF S94-8012007 standard “Reinforcement implants set into place via a vaginal route for an urge and/or prolapsus urinary incontinence cure for pelvic organs—pre-clinical tests and clinical tests”—§ 5.2.3, 5 samples 50×100 mm, USP 2/0 suture yarn, crosshead speed: 100 mm/min [0110] in the warp direction: 30±3 N [0111] in the weft direction: 46±2 N

[0112] The above test is conducted on a tensile testing machine Hounsfield HSKS-SN 0589.

[0113] The knit retains its three-dimensional structure even when it is subject to compressive forces tending to press its front face onto its rear face.

[0114] This knit is useful for manufacturing reinforcement prosthesis for example for repairing hernias. It is sufficient to cut out the intended shape, for example a rectangular (see FIG. 5) or circular shape (see FIG. 4), in the knit of the present example in order to obtain a prosthesis which may be used as a wall reinforcement for treating hernia. A prosthesis according to the invention may consist of a knit according to the present example, alone, cut to the intended shape. Alternatively, the prosthesis may further comprise an anti-adhesion coating and/or one or more additional textile layers, as described with reference to FIGS. 4 and 5.

EXAMPLE 2

[0115] A knit suitable for the prosthesis according to the invention is produced with 88 dtex monofilament polyester yarns.

[0116] The knit is produced on a two-bed Rachel knitting machine with 4 threaded guide bars, 1 full stitch, 1 empty stitch, according to the following weave, according to the ISO 11676 standard:

[0117] BAV: 4.3.2.2/1.0.1.1/1.2.1.1/1.0.1.1/1.2.1.1/1.0.1.1/1.2.3.3/4.5.4.4/4.3.4.4/4.5.4.4/4.3.4.4/4.5.4.4//

[0118] BE1: 1.2.3.3/4.5.1.2/4.3.4.4/4.5.4.4/4.3.4.4/4.5.4.4/4.3.2.2/1.0.4.3/1.2.1.1/1.0.1.1/1.2.1.1/1.0.1.1//

[0119] BAR1: 4.4.4.3/2.2.1.0/1.1.1.2/1.1.1.0/1.1.1.2/1.1.1.0/1.1.1.2/3.3.4.5/4.4.4.3/4.4.4.5/4.4.4.3/4.4.4.5//

[0120] BAR2: 1.1.1.2/3.3.4.5/4.4.4.3/4.4.4.5/4.4.4.3/4.4.4.5/4.4.4.3/2.2.1.0/1.1.1.2/1.1.1.0/1.1.1.2/1.1.1.0

[0121] This weave is illustrated in FIG. 2, in which the bars BAV, BE1, BAR1, and BAR2, are indicated with for each bar the path of a yarn (indicated in solid line). In this figure, the numbers 1, 2, 3, . . . 15 indicate the rows of the stitches of the front face; the numbers 1′, 2′, 3′, . . . , 14′ indicate the rows of the stitches of the rear face. Also on this figure, a vertical sequence of points illustrates two columns of stitches, both front and rear, facing each other. In FIG. 2, the columns are indicated as n, n′, (n+1), (n′+1), (n+2), (n′+2), (n+3), (n′+3), (n+4) and (n′+4).

[0122] In the present example, the yarns of the BAV and BE1 bars form the front face, the yarns of the BAR1 and BAR2 bars form the rear face. In the present example, the connecting yarns are therefore yarns from a lap of the front face, i.e. the lap obtained with the BE1 bar. Thus, in the present example, there are no laps of connecting yarns dedicated to the formation of the spacer.

[0123] The weave followed for the front face produces a front face comprising pores. Also, the weave followed for the rear face produces a face comprising pores. The pores of the front face are substantially facing the pores of the rear face.

[0124] As this appears in FIG. 2, the yarn forming the spacer is the yarn of the BE1 bar which, at row n° 2 and at column (n+4), connects the front face to row n° 2′ of the rear face and to the column (n′+1) (see the arrow in the figure). By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by three columns and x′, as defined in the present application, is equal to 3. This yarn then connects row 2′, column (n′+1) of the rear face to row 3, column (n+3) of the front face. By doing this it rejoins the rear face to the front face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by two columns and x, as defined in the present application, is equal to 2.

[0125] Next this yarn connects the 8.sup.th row and column n of the front face to row 8′, column (n′+3) of the rear face (see the arrow in the figure). By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces and x is equal to 3. Next, the yarn connects row 8′, column (n′+3) of the rear face to row 9, column (n+1) of the front face and here, x′ is equal to 2.

[0126] Thus, the obtained spacer is formed with connecting yarns which regularly cross each other thereby generating an optimum entanglement of yarns not parallel with each other.

[0127] The thereby obtained spacer is particularly resistant to compressive forces tending to press the front face onto the rear face. Subject to such forces, the spacer neither collapses nor lies down parallel to the front and rear faces, thereby retaining its three-dimensional knitted structure.

[0128] This knit is useful for manufacturing reinforcement prosthesis for example for repairing hernias. It is sufficient to cut out the intended shape, for example a rectangular (see FIG. 4) or circular shape (see FIG. 5), in the knit of the present example in order to obtain a prosthesis which may be used as a wall reinforcement for treating a hernia. A prosthesis according to the invention may consist of a knit according to the present example, alone, cut out to the intended shape. Alternatively, the prosthesis may further comprise an anti-adhesion coating and/or one or more additional textile layers, as described with reference to FIGS. 4 and 5.

EXAMPLE 3

[0129] A knit suitable for the prosthesis according to the invention is produced with 88 dtex monofilament polyester yarns.

[0130] The knit is produced on a two-bed Rachel knitting machine with 4 threaded guide bars, 1 full stitch, 1 empty stitch, according to the following weave, according to the ISO 11676 standard:

[0131] BAV: 4.3.2.2/1.0.1.1/1.2.1.1/1.0.1.1/1.2.1.1/1.0.1.1/1.2.3.3/4.5.4.4/4.3.4.4/4.5.4.4/4.3.4.4/4.5.4.4//

[0132] BE1: 1.2.3.3/4.5.2.1/4.3.4.5/4.5.4.4/4.3.4.5/4.5.4.4/4.3.2.2/1.0.3.4/1.2.1.0/1.0.1.1/1.2.1.0/1.0.1.1//

[0133] BAR1: 4.4.4.3/2.2.1.0/1.1.1.2/1.1.1.0/1.1.1.2/1.1.1.0/1.1.1.2/3.3.4.5/4.4.4.3/4.4.4.5/4.4.4.3/4.4.4.5//

[0134] BAR2: 1.1.1.2/3.3.4.5/4.4.4.3/4.4.4.5/4.4.4.3/4.4.4.5/4.4.4.3/2.2.1.0/1.1.1.2/1.1.1.0/1.1.1.2/1.1.1.0

[0135] This weave is illustrated in FIG. 6, in which the bars BAV, BE1, BAR1, and BAR2, are indicated with for each bar the path of a yarn (indicated in solid line). In this figure, the numbers 1, 2, 3, . . . 15 indicate the rows of the stitches of the front face; the numbers 1′, 2′, 3′, . . . , 14′ indicate the rows of the stitches of the rear face. Also on this figure, a vertical sequence of points illustrates two columns of stitches, both front and rear, facing each other. In FIG. 6, the columns are indicated as n, n′, (n+1), (n′+1), (n+2), (n′+2), (n+3), (n′+3), (n+4) and (n′+4).

[0136] In the present example, the yarns of the BAV and BE1 bars form the front face, the yarns of the BAR1 and BAR2 bars form the rear face. In the present example, the connecting yarns are therefore yarns from a lap of the front face, i.e. the lap obtained with the BE1 bar. Thus, in the present example, there are no laps of connecting yarns dedicated to the formation of the spacer.

[0137] The weave followed for the front face produces a front face comprising pores. Also, the weave followed for the rear face produces a face comprising pores. The pores of the front face are substantially facing the pores of the rear face.

[0138] As this appears in FIG. 6, the yarn forming the spacer is the yarn of the BE1 bar which, at row n° 2 and at column (n+4), connects the front face to row n° 2′ of the rear face and to the column (n′+1). By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by three columns and x′, as defined in the present application, is equal to 3. This yarn then connects row 2′, column (n′+1) of the rear face to row 3, column (n+3) of the front face. By doing this it rejoins the rear face to the front face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by two columns and x, as defined in the present application, is equal to 2.

[0139] This yarn also connects the 8.sup.th row and column n of the front face to row 8′, column (n′+3) of the rear face. By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces and x is equal to 3. Next, the yarn connects row 8′, column (n′+3) of the rear face to row 9, column (n+1) of the front face and here, x′ is equal to 2.

[0140] Thus, the obtained spacer comprises connecting yarns which regularly cross each other thereby generating an optimum entanglement of yarns not parallel with each other.

[0141] In addition, in the present example, the yarn of the BE1 bar forms additional connections between the front face and the rear face, in which the connecting yarns do not cross each other: these additional connections may be seen on FIG. 6 at rows 3, 5, 9 and 11.

[0142] Indeed, at row n° 3 and at column (n+3), the yarn connects the front face to row n° 3′ of the rear face and to the column (n′+4). By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by one column. This yarn then connects row 3′, column (n′+4) of the rear face to row 4, column (n+4) of the front face. By doing this it rejoins the rear face to the front face perpendicularly to these faces, with no shift of column. The same phenomenon is repeated starting at row 5.

[0143] In addition, at row n° 9 and at column (n+1), the yarn connects the front face to row n° 9′ of the rear face and to the column n′. By doing this, it rejoins the front face to the rear face obliquely and not perpendicularly to these faces: in this example, the yarn is shifted by one column. This yarn then connects row 9′, column n′ of the rear face to row 10, column n of the front face. By doing this it rejoins the rear face to the front face perpendicularly to these faces, with no shift of column. The same phenomenon is repeated starting at row 11.

[0144] Such additional connections between the front and the rear face, with connecting yarns which are yarns from a lap of the front face, bring additional resistance to compressive force to the knitted structure.

[0145] The thereby obtained spacer is particularly resistant to compressive forces tending to press the front face onto the rear face. Subject to such forces, the spacer neither collapses nor lies down parallel to the front and rear faces, thereby retaining its three-dimensional knitted structure.

[0146] The obtained knit has the following properties:

[0147] 1°) Thickness: 1.3 mm

[0148] By its structure, the knit of the present example substantially retains its height even when it is subject to a compressive force tending to press its front face onto the rear face.

[0149] 2°) Transparence and Size of the Pores for Both Front and Rear Faces: [0150] pores (width×height): 2.0×3.3 mm

[0151] By the structure of the knit of the present example, the pores of the front face remain facing the pores of the rear face, even when the knit is subject to a compressive force tending to compress its front face onto its rear face.

[0152] FIG. 7 is a view taken with a scanning electron microscope of one face of the knit of the present example. As this is apparent from this view, the pores of the front face and of the rear face are aligned on each other so that it is possible to clearly see the background behind the knit through the knit: the pores of the front face and those of the rear face are facing each other. Thus, the knit has excellent transparence which allows the surgeon to handle a prosthesis comprising such a knit with facility and to easily position it, in particular with respect to the surrounding organs. Indeed, the knit of the prosthesis allows the surgeon to have good visibility in transparence of the surrounding organs.

[0153] 3°) Suture strength, as measured according to the NF S94-8012007 standard “Reinforcement implants set into place via a vaginal route for an urge and/or prolapsus urinary incontinence cure for pelvic organs—pre-clinical tests and clinical tests”—§ 5.2.3, 5 samples 50×100 mm, USP 2/0 suture yarn, crosshead speed: 100 mm/min [0154] in the warp direction: 46±3 N [0155] in the weft direction: 50±6 N

[0156] The above test is conducted on a tensile testing machine Hounsfield H5KS-SN 0589.

[0157] The knit retains its three-dimensional structure even when it is subject to compressive forces tending to press its front face onto its rear face.

[0158] This knit is useful for manufacturing reinforcement prosthesis for example for repairing hernias. It is sufficient to cut out the intended shape, for example a rectangular (see FIG. 4) or circular shape (see FIG. 5), in the knit of the present example in order to obtain a prosthesis which may be used as a wall reinforcement for treating a hernia. A prosthesis according to the invention may consist of a knit according to the present example, alone, cut out to the intended shape. Alternatively, the prosthesis may further comprise an anti-adhesion coating and/or one or more additional textile layers, as described with reference to FIGS. 4 and 5.