Patent Description:
<CIT> discloses an apparatus for treating a wound with negative pressure therapy and a method of manufacturing the apparatus. The apparatus comprises a bespoke wound filler. The bespoke wound filler may incorporate a stabilizing structure. In one example, the stabilizing structure is constructed as a single unit so as to form one or more cells. Two or more longitudinal strips (which form the walls of the cells) may have relatively straight configurations and are connected together via one or more collapsible cross strips. The collapsible cross strips may be angled or indented so as to make them more likely to collapse in a direction generally parallel to their length. The collapsible cross strip is more likely to collapse at the apex of the angled portion and at the junctions to the longitudinal strips when a force is applied in a direction approximately parallel to the general length of the collapsible cross strip.

<CIT> discloses a discontinuous hydrocolloid article. The discontinuous hydrocolloid article comprises a plurality of cross-linked polymer strands comprising a hydrophobic polymer and a hydrocolloid dispersed throughout the hydrophobic polymer, and a plurality of joining strands. Each polymer strand repeatedly contacts an adjacent joining strand at bond regions.

<CIT> discloses a manifold structure comprising a plurality of spaced longitudinal members and at least one shaped projection coupled to at least one of the longitudinal members for creating a microstrain at the tissue site.

Other known NPWT articles are discussed in <CIT>; <CIT>; <CIT> and <CIT>.

In one aspect, the present disclosure provides an article, including a network of interconnected polymeric strands; wherein each of the interconnected polymeric strands has a first surface adapted to contact a tissue site and a second surface opposite the first surface; wherein at least one of the interconnected polymeric strands has a plurality of protrusions on and extending from the first surface of said at least one interconnected polymeric strands; wherein at least one of the interconnected polymeric strands is non-linear; a plurality of openings between adjacent interconnected polymeric strands; an adhesive layer in contact with the second surface of the interconnected polymeric strands; and a filler in contact with the adhesive layer, the adhesive layer in between the network of interconnected polymeric strands and the filler; wherein the article is a negative pressure wound therapy article.

In another aspect, the present disclosure provides a system, including the article of present invention and a reduced pressure source connected to article to deliver the reduced pressure through the opening, between the protrusions, and to the tissue site.

Various aspects and advantages of exemplary embodiments of the present disclosure have been summarized. The above Summary is not intended to describe each illustrated embodiment or every implementation of the present disclosure. Further features and advantages are disclosed in the embodiments that follow. The Drawings and the Detailed Description that follow more particularly exemplify certain embodiments using the principles disclosed herein.

While the above-identified drawings, which may not be drawn to scale, set forth various embodiments of the present disclosure, other embodiments are also contemplated, as noted in the Detailed Description. In all cases, this disclosure describes the presently disclosed invention by way of representation of exemplary embodiments and not by express limitations. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope of the present invention.

Before any embodiments of the present disclosure are explained in detail, it is understood that the invention is not limited in its application to the details of use, construction, and the arrangement of components set forth in the following description. The invention is capable of other embodiments and of being practiced or of being carried out in various ways that will become apparent to a person of ordinary skill in the art upon reading the present disclosure. Also, it is understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including," "comprising," or "having" and variations thereof herein is meant to encompass the items listed thereafter as well as additional items. It is understood that other embodiments may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure.

As used in this Specification, the recitation of numerical ranges by endpoints includes all numbers subsumed within that range (e.g. <NUM> to <NUM> includes <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>, and the like).

The article of the present application is well suited to promote tissue growth at the tissue site yet prevent in-growth of new tissue into the article. The article of the present application can help to deliver a significant portion of microstrain to the wound site by the architecture of the article, for example, the surface morphology of the article and thus may allow for lower pressure settings for NPWT to be used (for example, -<NUM> mmHg vs -<NUM> mmHg). This may allow a longer battery life of the NPWT system and the use of smaller pumps for the NPWT.

Referring to <FIG>, an article <NUM> according to an embodiment of the present invention includes a network of interconnected polymeric strands, or sheets <NUM> and a plurality of openings <NUM> between adjacent polymeric strands. Polymeric strands <NUM> can be connected at connections <NUM>. Typically, there are a plurality of connections <NUM> between adjacent strands. Polymeric strands <NUM> have a tissue contact surface <NUM> as a first surface and a second surface <NUM> opposite the first surface. The first surface <NUM> may include a plurality of protrusions <NUM> that extend from the first surface <NUM>. In some embodiments, the protrusions <NUM> do not substantially contact each other (i.e., at least <NUM> (at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even <NUM>) percent by number do not contact each other). The openings <NUM> form or provide open fluid channels from the first surface <NUM> of the network of polymeric strands to a second surface opposite first surface <NUM>. Through the open fluid channels, openings <NUM> are typically used to allow reduced pressure applied to a tissue site.

Referring more specifically to <FIG>, the height, H1, of each polymeric strand <NUM> may be up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, or up to <NUM> micrometers. In some embodiments, the height, H1, of each polymeric strand <NUM> may be no less than <NUM> micrometers, no less than <NUM> micrometers, or no less than <NUM> micrometers. In some embodiments, the height, H1, of each polymeric strand <NUM> may be between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers or between <NUM> and <NUM> micrometers. In some embodiments, the thickness, T, of each polymeric strand <NUM> may have an average width up to <NUM> micrometers, up to <NUM> micrometers, or up to <NUM> micrometers. In some embodiments, the thickness, T, of each polymeric strand <NUM> may have an average width no less than <NUM> micrometers. In some embodiments, the thickness, T, of each polymeric strand <NUM> may have an average width in a range from <NUM> micrometers to <NUM> micrometers, from <NUM> micrometers to <NUM> micrometers, or <NUM> micrometers to <NUM> micrometers. In some embodiments, the article comprising interconnected polymeric strands has an average thickness not greater than <NUM>. In one embodiment of the present invention, the height and thickness of the interconnected polymeric strands <NUM> is uniform for a particular article <NUM>. In other embodiments, the height and thickness of the interconnected polymeric strands <NUM> may be different. For example, the interconnected polymeric strands <NUM> having different height. Similarly, thickness of the interconnected polymeric strands <NUM> may vary. In some, embodiments, the interconnected polymeric strands <NUM> may have a range of thicknesses, for example, the interconnected polymeric strands <NUM> tends to be thinnest where it abuts an opening.

In some embodiments, the article comprising interconnected polymeric strands has a thickness up to <NUM>, up to <NUM>, up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, or up to <NUM> micrometers. In some embodiments, the article comprising interconnected polymeric strands has a thickness no less than <NUM> micrometers. In some embodiments, the article comprising interconnected polymeric strands has a thickness in a range from <NUM> micrometers to <NUM>, <NUM> micrometers to <NUM>, <NUM> micrometers to <NUM> micrometers, <NUM> micrometers to <NUM> micrometers, <NUM> micrometers to <NUM> micrometers, <NUM> micrometers to <NUM> micrometers, <NUM> micrometers to <NUM> micrometers, <NUM> micrometers to <NUM> micrometers, or <NUM> micrometers to <NUM> micrometers. In some embodiments, the article comprising interconnected polymeric strands has an average thickness in a range from <NUM> micrometers to <NUM>.

In some embodiments, at least one of the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, at least <NUM>% of the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, at least <NUM>% of the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, at least <NUM>% of the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, essentially all the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, all of the interconnected polymeric strands <NUM> may be non-linear. In some embodiments, the non-linear polymeric strand may have a shape of a curve. In some embodiments, the non-linear polymeric strand may have a shape of a sinusoidal curve. In some embodiments, the non-linear polymeric strand may have a shape of a sinusoidal curve. In other embodiments, at least one of the interconnected polymeric strands <NUM> may be linear. In some other embodiments, <NUM>% to <NUM>% of the interconnected polymeric strands <NUM> may be linear. In some other embodiments, <NUM>% to <NUM>% of the interconnected polymeric strands <NUM> may be linear. In certain embodiments, the network of interconnected polymeric strands may include alternating non-linear polymeric strands and linear polymeric strands, as shown in <FIG>. In some embodiments, the interconnected polymeric strands <NUM> are oriented in the same direction, for example, x direction as illustrated in <FIG>. In some embodiments, the interconnected polymeric strands <NUM> do not substantially cross over each other (i.e., at least <NUM> (at least <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even <NUM>) percent by number do not cross over each other).

In some embodiments, aspect ratio (a ratio of the length to the width) of the openings <NUM> may be greater than <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM> or <NUM>:<NUM>. In some embodiments, aspect ratio (a ratio of the length to the width) of the openings <NUM> may be in a range from <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM><NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, <NUM>:<NUM> to <NUM>:<NUM>, or <NUM>:<NUM> to <NUM>:<NUM>. The length, L1, of an opening <NUM> illustrated in <FIG> is the longest lateral distance parallel to x direction, for example, the length between connections A and C. If the non-linear polymeric strand has a shape of a sinusoidal curve, the length of the opening <NUM> equals the wavelength of the sinusoidal curve. The width, W1, of an opening <NUM> illustrated in <FIG> is the longest distance parallel to y direction. If the non-linear polymeric strand has a shape of a sinusoidal curve, the width of the opening <NUM> equals two times amplification of the sinusoidal curve. Openings <NUM> of the article may have a range of L1 and W1 values as a result in part of variable spacing of the connections A and B. In some embodiments, the openings have widths, W1, up to <NUM>, up to <NUM> or up to <NUM>. In some embodiments, the openings have widths, W1, at least <NUM> micrometers or at least <NUM> micrometers. In some embodiments, the openings have widths, W1, in a range from <NUM> micrometers to <NUM> or from <NUM> micrometers to <NUM>. In some embodiments, the openings have lengths, L1, up to <NUM> or up to <NUM>. In some embodiments, the openings have lengths, L1, at least <NUM> micrometers. In some embodiments, the openings have lengths, L1, in a range from <NUM> micrometers to <NUM> or from <NUM> micrometers to <NUM>. <FIG> are idealized illustrations of one embodiment of the present application. In some embodiments, the openings <NUM> may have irregularly formed perimeters. This can mean that the openings have irregular shapes (that is, no lines of symmetry). They may have edges that are not smooth (e.g., jagged or feathery edges). Irregularly formed openings can also have a variety of thicknesses of the polymeric strands surrounding the openings.

In some embodiments, openings <NUM> may have any suitable shape, for example, a shape selected from shapes of ellipse, oval, pointed oval (or lens), diamond, ½ ellipse, ½ oval, ½ lens, triangle, etc. In some embodiments, the openings of the mechanical fastening nets described herein have at least two pointed ends. In some embodiments, at least some of the openings are elongated with two pointed ends. In some embodiments, at least some of the openings are elongated with two opposed pointed ends. In some embodiments, at least some of the openings are ovals.

In some embodiments, the article described herein have a total open area for each of the first and second, generally opposed surfaces of not greater than <NUM> (in some embodiments, not greater than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>. <NUM>, <NUM>, <NUM>, <NUM><NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even not greater than <NUM>) percent of the total area of the respective surface. In some embodiments, for at least a majority of the openings of the article described herein, the maximum area of each opening is not greater than is <NUM> (in some embodiments, not greater than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or even not greater than <NUM>) mm<NUM>. Individual openings range from <NUM><NUM> to <NUM><NUM>. In some embodiments, the article according to the present disclosure have in a range from <NUM>,<NUM> to <NUM>,<NUM>,<NUM> (in some embodiments, <NUM>,<NUM> to <NUM>,<NUM>,<NUM>, <NUM>,<NUM> to, <NUM>,<NUM>,<NUM>, or even <NUM>,<NUM>,<NUM> to <NUM>,<NUM>,<NUM>) openings/m<NUM>.

In some embodiments, the tensile strength of the article parallel to x direction may be greater than the tensile strength of the article parallel to y direction. Therefore, the article is easier to be stretched in y direction than in x direction. In some embodiments, the tensile strength of the article parallel to x direction is at least <NUM> MPa, at least <NUM> MPa, at least <NUM> MPa or at least <NUM> MPa. In some embodiments, the tensile strength of the article parallel to x direction is up to <NUM> MPa, up to <NUM> MPa, up to <NUM> MPa, or up to <NUM> MPa. In some embodiments, the tensile strength of the article parallel to x direction is from <NUM> MPa to <NUM> MPa. , from <NUM> MPa to <NUM> MPa or from <NUM> MPa to <NUM> MPa. The Young's modulus of the article is up to <NUM> MPa, up to <NUM> MPa, up to <NUM> MPa, or up to <NUM> MPa. The Young's modulus of the article is at least <NUM> MPa, at least <NUM> MPa has a range from <NUM> MPa to <NUM> MPa in a direction parallel to x direction.

The shape, sizing, and spacing of the protrusions <NUM> may vary depending upon the particular tissue site being treated, the type of material from which the protrusions <NUM> and polymeric strands are made, and the amount of reduced pressure being applied to the tissue site. For example, for tissue sites that are highly exudating, it may be advantageous to position the protrusions farther apart or reduce the density of protrusions on the first surface to maintain adequate distribution channels between the protrusions <NUM>. In one embodiment of the present invention, the shape, sizing and spacing of the protrusions <NUM> is uniform for a particular article <NUM>. In other embodiments, the shape, sizing, and spacing of the protrusions <NUM> may be different. For example, protrusions <NUM> having different cross-sectional shapes may be disposed on the first surface. Similarly, the sizing and spacing of the protrusions <NUM> may vary to supply selected portions of the tissue site with different (more or less) reduced pressure and different flow rate for exudates withdrawn.

Referring more specifically to <FIG>, the height, H2, of the protrusions <NUM> may be up to <NUM> micrometers, up to <NUM> micrometers or up to <NUM> micrometers. In some embodiments, the height, H2, of the protrusions <NUM> may be at least <NUM> micrometers or at least <NUM> micrometers. In some embodiments, the height, H2, of the protrusions <NUM> may be between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers or between <NUM> and <NUM> micrometers. The width, W2, of each feature may be up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers, up to <NUM> micrometers or up to <NUM> micrometers. In some embodiments, the width, W2, of each feature may be at least <NUM> micrometers, at least <NUM> micrometers, at least <NUM> micrometers, at least <NUM> micrometers or at least <NUM> micrometers. In some embodiments, the width, W2, of each feature may be between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers, between <NUM> and <NUM> micrometers, or between <NUM> and <NUM> micrometers. In some embodiments, the width, W2, of each feature may be <NUM> micrometers. The width of the protrusions <NUM> illustrated in <FIG> is an edge length of the square since the cross-sectional shape of each protrusions <NUM> is square. If the protrusions <NUM> are circular in cross-sectional shape, the width of the protrusions <NUM> equals the diameter since the cross-sectional shape of each feature <NUM> is circular. For other cross-sectional shapes, the width is the average of the longest lateral distance through the centroid, C, of the cross section and the shortest lateral distance through the centroid of the cross section. It is generally preferred that the height of the protrusions <NUM> be no more than the width of the protrusions <NUM>. More specifically, the ratio of height to width, H2:W2 of the protrusions <NUM>, should be no more than <NUM>:<NUM>. When the ratio of height to width, H2:W2 of the protrusions <NUM>, is more than <NUM>:<NUM>, the protrusions <NUM> is more prone to fall over the openings <NUM>, thus reducing the fluid flow through the openings <NUM>. The lateral, center-to-center spacing, E, between each feature <NUM> may be between <NUM> and <NUM> millimeters, between <NUM> and <NUM> millimeters or between <NUM> and <NUM> millimeters. The spacing of the protrusions <NUM> create distribution channels through which reduced pressure may be delivered to the tissue site and exudates withdrawn from the tissue site. The density of protrusions on the first surface may be less than <NUM>,<NUM>/square inch to facilitate reduced pressure delivered to the tissue site and exudates withdrawn from the tissue site. In some embodiments, the density of protrusions on the first surface may be less than <NUM>,<NUM>/square inch, less than <NUM>/square inch, less than <NUM>/square inch, less than <NUM>/square inch, less than <NUM>/square inch, or less than <NUM>/square inch. In some embodiments, the number of protrusions in the article can be greater than the number of openings. For example, the ratio of the number of protrusions to the number of openings can be more than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>. In some embodiments, the article of the present disclosure can be a mechanical fastening net or a mechanical fastening sheet with protrusions.

In some embodiments, protrusions <NUM> are oriented along the interconnected polymeric strands <NUM> as illustrated in <FIG>. In other embodiments, protrusions <NUM> are oriented in substantially same orientation, for example x direction, as illustrated in <FIG>.

The presence and sizing of the protrusions <NUM> allow the protrusions <NUM> to distribute reduced pressure to the tissue site, but prevent new tissue that grows at the tissue site from attaching to the protrusions <NUM> or growing into the spacing between protrusions <NUM>. While new tissue growth may wrap around some of the protrusions <NUM>, the new tissue is not capable of securing itself to the protrusions <NUM> since the base of each protrusions is anchored to the first surface <NUM>.

In addition to distributing reduced pressure to the tissue site, the article <NUM> also serves to impart stresses and strains to the tissue site similar to those seen with cellular foam that traditionally has been used in reduced pressure systems. Other materials sometimes used in reduced pressure systems, such as gauze, do not have this effect on tissue. Unbound by the theory, the stresses and strains created by the article <NUM> are believed to cause micro-deformation of existing tissues and plays a significant role in the generation of new tissues at the tissue site. The amount of stress and strain imparted to a tissue site is determined by the amount of reduced pressure supplied to the tissue site and the surface morphology of the article that contacts the tissue site. As reduced pressure is applied, portions of the tissue site are pulled against the article <NUM>, and more particularly against the protrusions <NUM>, which results in the development of stresses and strains within the tissue. In some embodiments, the article of the present disclosure can be a mechanical fastening net or a mechanical fastening sheet with protrusions.

Referring to <FIG>, in some embodiments, the article <NUM> may further include an adhesive layer <NUM> in contact with the second surface <NUM> of the interconnected polymeric strands <NUM>. Suitable adhesive for use in the adhesive layer <NUM> of the article <NUM> can include any adhesive that provides acceptable adhesion to skin and is acceptable for use on skin (e.g., the adhesive should preferably be non-irritating and non-sensitizing). Suitable adhesives can be pressure sensitive and in certain embodiments have a relatively high moisture vapor transmission rate to allow for moisture evaporation. Suitable pressure sensitive adhesives include those based on acrylates, urethane, hyrdogels, hydrocolloids, block copolymers, silicones, rubber based adhesives (including natural rubber, polyisoprene, polyisobutylene, butyl rubber etc.) as well as combinations of these adhesives. The adhesive component may contain tackifiers, plasticizers, rheology modifiers as well as active components including for example an antimicrobial agent. Suitable adhesive can include those described in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT> and International Publication Nos. <CIT>; <CIT> and <CIT>.

The article <NUM> may further include a filler <NUM> in contact with the adhesive layer <NUM>, the adhesive layer <NUM> in between the network of interconnected polymeric strands <NUM> and the filler <NUM>. The filler is useful to allow for fluid transport under vacuum into the filler, but with the contact layer providing an interface between the tissue and the filler. Representative filler may include non-woven and woven fibrous webs, knits, films, foams polymeric films and other familiar filler materials. The protrusions <NUM> and interconnected polymeric strands serve as a barrier to new tissue growth entering pores of the filler <NUM>. In some embodiments, the filler can be a foam. In some embodiments, the filler can be a cellular foam. In some embodiments, the filler can be an open cellular foam. In some embodiments, the filler can be a closed cellular foam. In some embodiments, the filler can comprises an elastomeric polyurethane, polyester, or polyether block amide foam or film.

The article <NUM> may further include an occlusive layer <NUM> to cover the filler, adhesive layer and the contact layer. The occlusive layers are useful to provide an impermeable barrier to the passage of liquids and at least some gases and help to deliver and distribute reduced pressure to the article <NUM>. Representative barriers may include non-woven and woven fibrous webs, knits, films, foams polymeric films and other familiar backing materials. In some embodiments, a transparent occlusive layer is desirable to allow for viewing of the underlying subjects. Suitable occlusive layers may include those described in International Publication No. <CIT>.

In one embodiment, the occlusive layer has high moisture vapor permeability, but generally impermeable to liquid water so that microbes and other contaminants are sealed out from the area under the article. One example of a suitable material is a high moisture vapor permeable film such as described in <CIT> and <CIT>. In one embodiment, the occlusive layer can be an elastomeric polyurethane, polyester, or polyether block amide films. These films combine the desirable properties of resiliency, elasticity, high moisture vapor permeability, and transparency. A description of this characteristic of occlusive layers can be found in issued <CIT> and <CIT>.

Commercially available examples of potentially suitable materials for the occlusive layer may include the thin polymeric film sold under the trade names TEGADERM (<NUM> Company), OPSITE (Smith & Nephew), etc. Because fluids may be actively removed from the sealed environments defined by the article, a relatively high moisture vapor permeable occlusive layer may not be required. As a result, some other potentially useful materials for the occlusive layer may include, e.g., metallocene polyolefins and SBS and SIS block copolymer materials could be used.

Regardless, however, it may be desirable that the occlusive layer be kept relatively thin to, e.g., improve conformability. For example, the occlusive layer may be formed of polymeric films with a thickness of <NUM> micrometers or less, or <NUM> micrometers or less, <NUM> micrometers or less, or <NUM> micrometers or less.

Referring to <FIG>, a reduced pressure treatment system <NUM> according to an embodiment of the present invention includes a reduced pressure dressing, or article <NUM> fluidly connected to a reduced pressure conduit <NUM>. The reduced pressure conduit <NUM> is fluidly connected to a reduced pressure source <NUM> such as a vacuum pump or another source of suction. The article <NUM> is placed against a tissue site <NUM> of a patient and is used to distribute a reduced pressure provided by the reduced pressure source <NUM>. Typically, reduced pressure is maintained at the tissue site by placing an impermeable or semi-permeable cover <NUM> over the article <NUM> and the tissue site <NUM>. The reduced pressure also serves to draw wound exudates and other fluids from the tissue site <NUM>. A canister <NUM> may be fluidly connected to the reduced pressure conduit <NUM> and disposed between the article <NUM> and the reduced pressure source <NUM> to collect the fluids drawn from the tissue site <NUM>. A distribution adapter <NUM> may be connected to the reduced pressure conduit <NUM> and positioned on the article <NUM> to aid in distributing the reduced pressure to the article <NUM>.

In some embodiments, the interconnected polymeric strands <NUM> can include an elastomeric polymer. Elastomeric polymer can be any suitable elastomeric polymer, including but not limited to polyolefins and polyurethanes. In some embodiments, elastomeric polymer can be a medical grade material that is relatively impermeable to fluid flow. Alternatively, elastomeric polymer can be a semi-permeable material that allows select fluids or amounts of fluids to pass. In some embodiments, the interconnected polymeric strands <NUM> are formed from the same material as the protrusions <NUM>. In some embodiments, the interconnected polymeric strands <NUM> can be formed from a different material as the protrusions <NUM>. In some embodiments, the composition of interconnected polymeric strands <NUM> may be formed from different materials.

Wound-treatment methods using articles of the present invention can include positioning the article on a wound of a patient and applying a reduced pressure to the wound through the article (e.g., through the openings). Such methods can further comprise: coupling a drape to skin adjacent the wound such that the drape covers the article and the wound, and forms a space between the drape and the wound. In some cases, positioning the article on the wound can include placing the article over the wound with the protrusions on the first surface facing the wound. In some cases, applying the reduced pressure to the wound comprises activating a vacuum source (e.g., reduced pressure source <NUM> of <FIG>) that is coupled to the article. Some cases may comprise: delivering a fluid to the wound through the article. In some cases, delivering a fluid comprises activating a fluid source that is coupled to the article.

The following working examples are intended to be illustrative of the present disclosure and not limiting.

A polyolefin net was prepared using ENGAGE <NUM> polyolefin elastomer (obtained from the Dow Chemical Company, Midland, MI) according to the methods described in <CIT>). The resulting net material had strand width ranges of about <NUM>-<NUM>, pore width ranges of about <NUM>-<NUM>, pore length ranges of about <NUM>-<NUM>, and a thickness range of about <NUM>-<NUM>. The net sample was embossed by stacking from top to bottom a steel plate, a square pattern polypropylene film that served as the mold (inner dimension of a square being approximately <NUM>), the polyolefin net sample, a release liner, and a second steel plate. The stack was placed in a Carver Auto Series NE Automatic Hydraulic Press (Model <NUM>. 4NE1000, Carver Inc. , Wabasha, IN) with the bottom platen of the press set at <NUM> and the top platen set at <NUM>. The press was closed and the sample was held at a set force of <NUM> for two minutes, followed by a cool down period of four minutes to <NUM>. The press was opened and the embossed sample was removed from the press. The resulting embossed article had a base thickness range of about <NUM>-<NUM>; strand width ranges of about <NUM>-<NUM>; openings with width ranges of about <NUM>-<NUM> and length ranges of about <NUM>-<NUM>; protrusions with width at base of about <NUM> and height ranges of about <NUM>-<NUM>; and protrusion spacing ranges of about <NUM>-<NUM>.

An <NUM> by <NUM> section of the embossed article was prepared and the surface of the article without protrusions was modified by corona treatment for about one minute using a hand-held unit with rastering motion (Model BD-<NUM> Laboratory Corona Treater, Electro-Technic Products Company, Chicago, IL). One surface of an <NUM> by <NUM> (<NUM> thick) pad of GRANUFOAM polyurethane foam (V. Granufoam Dressing Medium, KCI Incorporated, San Antonio, TX) was also modified using the corona treatment procedure described above.

An <NUM> by <NUM> section of <NUM> #<NUM> Double-Coated TPE Silicone/Acrylic adhesive tape (<NUM> Company, Maplewood, MN) that had been perforated (<NUM> diameter perforations patterned <NUM> center-to-center) was prepared. The paper release liner was removed and the exposed adhesive surface was heated for <NUM>-<NUM> seconds with hot air from an electric heat gun. The adhesive tape was edge aligned and applied to the corona treated surface of the foam pad. Next, the plastic release liner was removed from the tape and the corona treated surface of the embossed article was edge aligned and applied to the exposed adhesive surface. Hand pressure was applied to the resulting laminate for <NUM>-<NUM> seconds followed by placement of a <NUM> weight on the laminate overnight. The weight was removed to provide the finished laminated article.

A double sided acrylic adhesive transfer tape (<NUM> 300LSE tape #9472LE, <NUM> Company) was perforated through all layers in a repeating hexagonal pattern with <NUM> diameter perforations spaced <NUM> center-to-center. A <NUM> by <NUM> section of the embossed article of Example <NUM> was prepared and the surface of the article without protrusions was modified by corona treatment for <NUM>-<NUM> seconds using a hand-held unit with rastering motion (Model BD-<NUM> Laboratory Corona Treater). One surface of a <NUM> by <NUM> (<NUM> thick) pad of GRANUFOAM polyurethane foam (V. Granufoam Dressing Medium) was also modified using the corona treatment procedure described above.

One of the release liners was removed from a <NUM> by <NUM> section the double sided adhesive transfer tape and the exposed adhesive surface was heated for <NUM>-<NUM> seconds with hot air from an electric heat gun. The adhesive was edge aligned and applied to the corona treated surface of the foam pad. Next, the second release liner was removed and the corona treated surface of the embossed article was edge aligned and applied to the exposed adhesive surface. Hand pressure was applied to the resulting laminate for a few seconds followed by placement of a <NUM> weight on the laminate overnight. The weight was removed to provide the finished laminated article.

A cell culture device having a lower base unit, an o-ring seal in the lower base unit, an upper base unit, a cell culture insert for growing cell cultures, a flexible sealing member, a guide tube with two open ends, a support bracket, a vacuum conduit, a media conduit, and attachment screws was used. The lower base unit had a circular interior cavity. The upper base unit was placed on top of lower base unit. The upper base unit had an open, interior channel that was dimensioned to align with the cavity opening of the lower base unit. The o-ring seal was pressed into a recess in the wall of the lower base unit. The cell culture insert was placed in the channel and pressed into the sealing element. The seal engaged the sidewalls of the cell culture insert to create a substantially air-tight seal. The base of the cell culture insert contained a permeable membrane. An upper assembly comprising a flexible sealing member, guide tube, and support bracket was placed on top of the upper base unit so that the guide tube was in fluid communication with the cell culture insert. The components of the device were then secured together with screws. The vacuum conduit was attached at one end to the guide tube and at the other end to a vacuum pump. The media conduit was connected at one end to a reservoir containing media and at the other end to the internal cavity of the lower base unit (near the floor). The media was pumped from the reservoir so that it flowed into the cavity of the lower base unit and then passed through the permeable membrane of the insert to the gel matrix.

Fibroblasts were encapsulated in a fibrin gel matrix (clot) to simulate a component of the wound healing environment. The matrix was prepared by the following three step procedure. First, a layer of fibrin gel was prepared and applied to the internal surface of the permeable membrane (<NUM> diameter with <NUM> micron pore size) in a MILLICELL hanging cell culture insert (obtained from EMD Millipore, Billerica, MA) by combining <NUM> of human fibrinogen (concentration of <NUM> per mL of porcine plasma) with <NUM> of thrombin (concentration of <NUM>-<NUM> units per mL of porcine plasma) (human fibrinogen obtained from Sigma-Aldrich Corporation, St. Louis, MO; thrombin obtained from BioPharm Laboratories, Bluffdale, UT; porcine plasma obtained from Lampire Biological Lab, Piphersville, PA). This layer was covered with a layer of about <NUM>,<NUM> fibroblasts (obtained from Invitrogen Corporation, Carlsbad, CA). The fibroblast layer was then covered with a third (or top layer) of fibrin gel prepared in the same manner as for the first layer. Following encapsulation in the gel, the fibroblasts were grown in an incubator at <NUM> for two days.

In the cell proliferation assay, the finished article of Example <NUM> (<NUM> by <NUM>) was placed over the top layer of the matrix with the surface of the article containing the feature elements facing and in contact with the gel matrix. Fibroblast Culture Medium <NUM> (obtained from Invitrogen Corporation) was continuously supplied to the gel matrix by means of a peristaltic pump. Negative pressure (-<NUM> Hg) was applied to the device for <NUM> hours at <NUM>. The device was then dismantled and the fibroblast sample was evaluated for cell proliferation using an XTT colorimetric assay kit (obtained from Invitrogen Corporation) with the absorbance measurements taken at <NUM> using a SpectraMax M5 plate reader (Molecular Devices, Sunnyvale, CA). The level of fibroblast cell proliferation for the example was compared to a control experiment. In the control experiment, the same procedure was used except that the finished article of Example <NUM> was not added to the apparatus and negative pressure was not applied for the <NUM> hour test period. In Table <NUM>, the mean percent increase in recorded absorbance for the example compared to the control is reported (<NUM> replicates).

Claim 1:
An article, comprising:
a network of interconnected polymeric strands; wherein each of the interconnected polymeric strands has a first surface adapted to contact a tissue site and a second surface opposite the first surface; wherein at least one of the interconnected polymeric strands has a plurality of protrusions on and extending from the first surface of said at least one interconnected polymeric strand; wherein at least one of the interconnected polymeric strands is non-linear;
a plurality of openings between adjacent interconnected polymeric strands;
an adhesive layer in contact with the second surface of the interconnected polymeric strands; and
a filler in contact with the adhesive layer, the adhesive layer in between the network of interconnected polymeric strands and the filler;
wherein the article is a negative pressure wound therapy article.