Strained skin treatment device and method

Abstract

The devices, kits, and methods described herein may include a dressing that is pre-strained and stored for a period of time, after which the dressing is applied to the skin of a subject. The devices, kits, and methods described herein may be for skin treatments where it is desirable to manipulate or modify the inherent or endogenous stress in the skin and / or control or manipulate the effect of exogenous stress on the skin. Such treatments may include, but are not limited to, wound treatments, or treatment, reduction, or prevention of scars and / or keloids, and / or treatment of wound dehiscence. According to the devices, kits, and methods described herein, the devices may be attached or coupled to one or more layers of the skin or tissue of a subject.

Description

[Background technology]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims priority to U.S. Provisional Patent Application No. 63 / 317,839, filed March 8, 2022, and entitled "STRAINED SKIN TREATMENT DEVICES AND METHODS," which is incorporated by reference in its entirety and for all purposes.

[0002] This application is related to U.S. Application No. 13 / 552,521, filed July 18, 2012, which is incorporated by reference in its entirety.

[0003] Scar formation in response to skin injury is part of the natural wound healing process. Wound healing is a continuous process over a period of time, but it is typically recognized as occurring in stages. The process begins with an inflammatory phase immediately after injury. During this phase, which typically lasts from 2 days to 1 week (depending on the wound), damaged tissue and foreign material are removed from the wound. The proliferative phase occurs some time after the inflammatory phase and is characterized by fibroblast proliferation and the production of collagen and proteoglycans. It is during the proliferative phase that the extracellular matrix is ​​synthesized to provide structural integrity to the wound. The proliferative phase usually lasts for about 4 days to several weeks, depending on the nature of the wound, and it is during this phase that a hypertrophic scar usually forms. The final stage is called the remodeling phase. During the remodeling phase, the previously organized and randomly organized matrix is ​​remodeled into a tissue structure that is highly cross-linked and aligned to increase mechanical strength.

[0004] Although the histological features that characterize hypertrophic scars have been well documented, the basic pathophysiology is not well known. Hypertrophic scars are a secondary effect of excessive wound healing, generally resulting in the overproduction of cells, collagen, and proteoglycans. Typically, these scars are elevated and characterized by a random distribution of tissue bundles. The appearance (i.e., size, shape, and color) of these scars varies depending on the part of the body where they form and the underlying ethnicity of the affected person. Hypertrophic scars are very common and can occur after any full-thickness injury to the skin. Recently, this has been shown in U.S. Patent Application Publication No. 2006 / 0037091 (U.S. Patent Application No. 11 / 135,992, filed May 24, 2005, entitled "Method for Producing Hypertrophic Scarring Animal Model for Identification of Agents for Prevention and Treatment of Human Hypertrophic Scarring"), which is incorporated herein by reference in its entirety, showing that mechanical stress can increase hypertrophic scarring in a mouse model.

[0005] Keloids are typically characterized as tumors consisting of highly proliferative masses that arise within the dermis and adjacent subcutaneous tissues of susceptible individuals, most commonly following trauma. Keloids are often more severe than hypertrophic scars because they tend to spread into normal adjacent tissues, whereas hypertrophic scars tend to remain confined within the original scar borders. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] US Patent Application Publication No. 2006 / 0037091 Summary of the Invention [Means for solving the problem]

[0007] The devices, kits, and methods described herein may be for skin treatments where it is desired to manipulate or modify the inherent or intrinsic stress in the skin and / or control or manipulate the effect of exogenous stress on the skin. Such treatments may include, but are not limited to, wound treatments, or treatment, reduction, or prevention of scars and / or keloids, and / or treatment of wound dehiscence. According to the devices, kits, and methods described herein, the devices may be attached or coupled to one or more layers of the skin or tissue of a subject.

[0008] In one variation, a skin treatment device is provided that includes a dressing comprising a pre-strained elastic member coupled to a strain-maintaining structure, the strain-maintaining structure configured to maintain the elastic member in a strained configuration, and the pre-strained elastic member configured to maintain at least a desired amount of tensile force for a predetermined period of time after an initial straining period. In some variations, the initial straining period is greater than about 24 hours, or greater than about one week. In other variations, the predetermined period may be at least 12 weeks, at least 24 weeks, or at least 52 weeks. The elastic member may exhibit less than about 5%, 15%, or 25% loss of force during the predetermined period. In some variations, the elastic member may exhibit at least about 25% or 35% loss of force, 40% loss, 45% loss, or more during the initial period. In some examples, the elastic member may exhibit a greater percentage loss of force during the initial period than during the predetermined period.

[0009] In another variation, a skin treatment device assembly is provided comprising a bandage having an elastic member, a support structure configured to be removably coupled to a pre-strained bandage and configured to maintain the pre-strained bandage in a strained configuration, a strain-applying element configured to pre-strain the bandage, the strain-applying element configured to be removably coupled to the support structure, a releasable locking element configured to maintain the pre-strained bandage in strain-maintaining engagement with the support structure, and a release mechanism configured to release the bandage from the support structure.

[0010] In another variation, a skin treatment device assembly is provided comprising a bandage comprising an elastic member, a straining element configured to couple to the bandage, pre-strain the bandage, and detach from the bandage, and a support structure removably coupled to the bandage and configured to maintain the bandage in the pre-strained configuration after the bandage is detached from the straining element.

[0011] In yet another variation, a method of manufacturing a bandage is provided that includes the steps of straining a bandage by a predetermined amount using a strain-imparting element, coupling the bandage in the strained configuration to a removable strain-retaining element in a releasable locking engagement to form a pre-strained assembly comprising the bandage and the strain-retaining element, and removing the strain-imparting element from the pre-strained assembly.

[0012] In another variation, a method of manufacturing a pre-strained bandage is provided that includes straining the bandage to an initial tensile force amount that exceeds a desired tensile force amount desired when the bandage is to be applied to a subject's skin, coupling the strained bandage to a removable strain-maintaining device, and suggesting a period of use of the bandage for a period of time when the tensile force amount is predicted to decrease by a desired reduced amount. The desired reduced amount may be reduced by about 25%, 35%, 40%, 45% or more than the initial tensile force. The desired reduced amount may be reduced by less than 25% than the initial tensile force.

[0013] In one variation, a skin treatment device is provided that includes a prestrained polymer structure and an unstrained adhesive layer attached to the prestrained polymer structure. The skin treatment device may further include a release liner attached to the unstrained adhesive layer. The prestrained polymer structure and the unstrained adhesive layer may be located within a sealed package. The sealed package may be a sterile sealed package.

[0014] In another variation, a method of manufacturing a skin treatment device is provided that includes straining an elastic polymer structure with a removable straining structure, applying an unstrained adhesive layer to a surface of the elastic polymer structure, and removing the straining structure. The method may further include attaching a release liner to the unstrained adhesive layer. The method may also further include encapsulating the elastic polymer structure and the unstrained adhesive layer in a sealed packaging structure, and optionally sterilizing the sealed packaging structure.

[0015] In one variation, a skin treatment device is provided that includes a pre-strained polymer structure, an adhesive layer attached to the pre-strained polymer structure, and an unstrained release liner attached to the adhesive layer.

[0016] In another variation, a method of manufacturing a skin treatment device is provided that includes straining an elastic polymer structure, applying an adhesive layer to a surface of the elastic polymer structure, and applying a release liner to the adhesive layer after straining the elastic polymer structure.

[0017] In one embodiment, a strained therapeutic device is provided that includes a strained elastic bandage, a support structure comprising a layer of adhesive on a surface of the elastic bandage and a polycoated paperboard with a Taber stiffness of at least 160, and two or more attachment structures located between the strained elastic bandage and the support structure, the attachment structures comprising flexible inelastic strips, the attachment structures adhered to the bandage by a high shear adhesive and thermally bonded to the polycoat of the paperboard, the area of ​​the thermal bond having a width in the range of 0.10 inches to 0.25 inches. The length of the area of ​​the thermal bond may be equal to or greater than the length of the adhesive bond between the attachment structures and the bandage.

[0018] In another embodiment, a method of making a strained therapeutic device is provided, comprising attaching a device carrier to a precursor bandage assembly, removing a manufacturing liner from the precursor bandage assembly, heat fusing a first region of the bandage to a first region of a support structure, straining the bandage and heat fusing a second region of the bandage in the strained configuration to a second region of the support structure, and applying an adhesive liner. The bandage may further comprise a first and a second attachment structure. The method may further comprise attaching a straining element to the bandage and retracting the straining element away from the first region of the bandage to strain the bandage. The method may further comprise lifting the straining element before retracting the straining element and lowering the straining element after retracting the straining element. Attaching the straining element to the bandage may occur after heat fusing the first region. The heat melting of the first and second regions of the dressing may be located on the first and second attachment structures. The first and second attachment structures may each include two lengths of perforations spaced apart from one another. The heat melting of the first and second regions may be performed to the sides of the two lengths of perforations on each of the attachment structures.

[0019] In another embodiment, a manufacturing assembly is provided that includes a transport assembly for moving a plurality of components along a movement path, a first clamp assembly configured to reversibly clamp together a first side of a subset of the plurality of components, a first thermal melt assembly configured to thermally melt the subset of the plurality of components together adjacent to the first side of the subset of the plurality of components, a distortion assembly including a second clamp assembly configured to reversibly clamp together a second side of the subset of the plurality of components, a first separation assembly configured to reversibly displace the second clamp assembly, and a second assembly configured to reversibly displace the distortion assembly away from the first clamp assembly, and a second thermal melt assembly configured to thermally melt the subset of the plurality of components together adjacent to the second side of the subset of the plurality of components. The first clamp assembly and the second clamp assembly may be configured to clamp in a first direction. The first separating assembly may be configured to lift the second clamp assembly in a second direction opposite the first direction. The second separating assembly may be configured to displace the straining assembly in a third direction orthogonal to the first direction. The assembly may further include a third clamp assembly configured to reversibly clamp the subset of the plurality of components together, the third clamp assembly being located between the first clamp assembly and the second clamp assembly. The third clamp assembly may be located between the first clamp assembly and the second thermal melt assembly. The assembly may further include a cutting assembly configured to cut the subset of the plurality of components. The cutting assembly may be configured to cut the subset of the plurality of components near a second side of the subset of the plurality of components.

[0020] In yet another embodiment, a distortion assembly or subassembly is provided comprising a first clamping assembly configured to reversibly clamp together a second side of a subset of the plurality of components, a first separating assembly configured to reversibly displace the second clamping assembly, a second assembly configured to reversibly displace the distortion assembly away from the first clamping assembly, and a first thermal melting assembly configured adjacent to the second side of the subset of the plurality of components to thermally melt the subset of the plurality of components together. [Brief description of the drawings]

[0021] [Figure 1A] FIG. 1A is a perspective view of a dressing and support structure in a first position.

[0022] [Figure 1B] FIG. 1B is a top perspective view of the dressing and support structure of FIG. 1A in a pre-strained configuration.

[0023] [Figure 1C] FIG. 1C is a bottom perspective view of the dressing and support structure of FIG. 1A in a pre-strained configuration.

[0024] [Figure 2A] FIG. 2A is a perspective view of the dressing and support structure in a first position.

[0025] [Figure 2B] FIG. 2B is a top perspective view of the dressing and support structure of FIG. 2A in a pre-strained configuration.

[0026] [Figure 3A] FIG. 3A is a top perspective view of the dressing assembly, support structure, and tensioning device in a relatively unstrained configuration.

[0027] [Figure 3B]FIG. 3B is a top perspective view of the dressing assembly, support structure, and tensioning device in a pre-strained configuration.

[0028] [Figure 3C] FIG. 3C is a schematic side view of the dressing assembly, support structure, and tensioning device of FIG. 3B.

[0029] [Figure 3D] FIG. 3D is an enlarged schematic cross-sectional side view of the dressing assembly, support structure and tensioning device of FIG. 3C.

[0030] [Figure 3E] FIG. 3E is an enlarged schematic detailed side view of a portion of the dressing and support structure of FIG. 3D.

[0031] [Figure 3F] FIG. 3F is a schematic side view of the dressing assembly and support structure in a pre-strained configuration.

[0032] [Figure 3G] FIG. 3G is an enlarged side view of the dressing assembly and support structure of section A of FIG. 3F.

[0033] [Figure 3H] FIG. 3H is an enlarged side view of the dressing assembly and support structure of section B of FIG. 3F.

[0034] [Figure 3I] FIG. 3I is a top perspective view of the pre-strained assembly, including the dressing assembly and the remaining elements of the support structure.

[0035] [Figure 4] FIG. 4 is a perspective view of a plurality of prestrained dressings on a support element.

[0036] [Diagram 5] FIG. 5 illustrates a pre-strained dressing and support structure.

[0037] [Figure 6] FIG. 6 illustrates the percent loss of force over time for an elastic bandage material as described in Example I.

[0038] [Figure 7] FIG. 7 is a schematic illustration of the percent force loss over time for a pre-strained elastic material component of a dressing.

[0039] [Figure 8] FIG. 8 is a schematic illustration of tensile force over time for a pre-strained elastic material component of a dressing.

[0040] [Figure 9] FIG. 9 illustrates the percent loss of force over time for an elastic bandage material as described in Example II.

[0041] [Figure 10A] FIG. 10A is a top view of the pre-strained assembly.

[0042] [Figure 10B] FIG. 10B is a cross section of FIG. 10A taken along line AA.

[0043] [Figure 11A] FIG. 11A is a flow chart illustrating the process and sub-processes for manufacturing a pre-strained dressing.

[0044] [Figure 11B] FIG. 11B is a flow chart illustrating a process for removing the production liner.

[0045] [Figure 11C] FIG. 11C is a flow chart illustrating a process for adhering a dressing to a support structure.

[0046] [Figure 11D] FIG. 11D is a flow chart illustrating a process for straining a dressing and attaching the dressing in a strained configuration to a support structure.

[0047] [Figure 11E] FIG. 11E is a flow chart illustrating a process for removal of a distortion element.

[0048] [Figure 11F] FIG. 11F is a flow chart illustrating the application of the adhesive liner.

[0049] [Figure 12A] FIG. 12A is a top perspective view of a roll of dressing pre-assembly.

[0050] [Figure 12B] FIG. 12B is a top view of the dressing preassembly of FIG. 12A.

[0051] [Figure 13] FIG. 13 is a top perspective view of the production unit.

[0052] [Figure 14] FIG. 14 is a top perspective view of the stage of the manufacturing unit of FIG.

[0053] [Figure 15A] FIG. 15A is a side view of the manufacturing assembly of FIG. 14 in a first step.

[0054] [Figure 15B] FIG. 15B is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0055] [Figure 15C] FIG. 15C is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0056] [Figure 15D] FIG. 15D is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0057] [Figure 15E] FIG. 15E is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0058] [Figure 15F] FIG. 15F is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0059] [Figure 15G] FIG. 15G is a side view of the manufactured assembly of FIG. 15A at a subsequent step.

[0060] [Figure 15H] FIG. 15H is a side view of the fabricated assembly of FIG. 15A at a subsequent step.

[0061] [Figure 16A] 16A is a top schematic view of the dressing assembly during and after the manufacturing assembly stage of FIG. 13. FIG.

[0062] [Figure 16B] 16B is a schematic top view of the dressing assembly before, during, and after the manufacturing assembly stage of FIG.

[0063] [Figure 16C] 16C is a top schematic view of the dressing assembly before, during, and after the manufacturing assembly stage of FIG.

[0064] [Figure 16D] 16D is a schematic top view of the dressing assembly before, during, and after the manufacturing assembly stage of FIG.

[0065] [Figure 16E]16E is a top schematic view of the dressing assembly before, during, and after the manufacturing assembly stage of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0066] Detailed Description In accordance with the devices, kits, and methods described herein, a skin treatment device, dermal device, wound treatment device, scar or keloid treatment device, scar or keloid reduction or prevention device, bandage, or dressing may be provided (hereinafter referred to as a "dressing," "skin device," or "skin treatment device") that may be applied to, attached to, or bonded to one or more layers of a subject's skin or tissue.

[0067] Described herein are devices that may be used to reduce the formation of scars and / or keloids at a wound site. The scar may be any type of scar, e.g., normal scar, hypertrophic scar, etc. In general, the device may be configured to be removably secured to a skin surface near the wound.

[0068] In addition to reducing scar formation, other uses for such skin treatment devices include, but are not limited to, treating skin-related conditions such as acne, age spots, rosacea, warts, rashes (including but not limited to erythematous, macular, papular, and / or bullous conditions), psoriasis, skin irritation / hypersensitivity, allodynia, telangiectasias, port wine stains and other arteriovenous malformations, and ectopic dermatitis; treating or ameliorating existing scars, wrinkles, stretch marks, loose or sagging skin, or other skin irregularities; during pre-operative preparation, e.g., as a thin tissue retractor to stabilize blood vessels during needle or catheter insertion, during a surgical procedure; post-operatively, e.g., prior to scar correction, wound incision, body contouring, pre- or post-operatively to pre-treat or pre-condition the skin, in mastectomy skin expansions, topically or subcutaneously. The devices may or may not include, for example, lifting, fixing, holding, and moving skin in aesthetic skin treatment or resurfacing, during weight loss, or for various purposes such as aesthetic purposes, whether using energy modalities such as microwave, radiofrequency ablation, high intensity focused ultrasound, laser, infrared, incoherent light, etc., hair removal or depilation, treating and / or closing skin injuries such as incisions, wounds, chronic wounds, pressure sores, ulcers (including venous stasis ulcers), preventing or reducing the occurrence of wound dehiscence, diabetic skin or wound conditions, burn healing and / or relief, acting as an occlusive or negative pressure wound dressing, protecting an incision or wound, for example, preventing splitting or opening, protecting the umbilicus of a newborn after cutting the umbilical cord. Such treatments may include the use of drugs or other therapeutic agents that may be applied to the skin using such devices. Agents may include, but are not limited to, antibiotics, antifungals, immune modulating components including corticosteroids and nonsteroidal immune modulating components. The agents may be provided in any of a variety of formulations, including, but not limited to, powders, gels, lotions, creams, pastes, suspensions, etc. The device may also be used for the purpose of delivering drugs to or through the skin, for example, by stretching the skin and applying the drug thereto.Different configurations of the device may be suitable for different body area sizes or geometries. Treatment may be applied to areas of any shape (e.g., linear, curvilinear, star-shaped), size, or depth, and to one or more areas of the body, including, but not limited to, the scalp, forehead, face (e.g., nose, eyelids, cheeks, lips, chin), ears, neck, shoulders, upper arms, forearms, palms, dorsa of hands, fingers, nail beds, armpits, breasts, nipples, areolae, back, abdomen, groin, buttocks, perineum, labia, penis, scrotum, thighs, lower legs, plantar surfaces of feet, dorsa of feet, and / or toes. Such devices may also be referred to herein as "dressings," "skin devices," or "skin treatment devices."

[0069] Unloading of extrinsic and / or intrinsic stress in the vicinity of a wound may reduce scar, hypertrophic scar, or keloid formation. The mechanical environment of an injury may be an important factor in tissue response to that injury. The mechanical environment includes extrinsic stress (i.e., physiological stress, including stress transmitted to the wound via muscle activity or physical movement) and intrinsic stress (i.e., epidermal stress resulting from the physical properties of the skin itself, including stress induced at the wound site due to swelling or contraction of the skin). The devices, dressings, kits, and methods described herein may control or regulate the mechanical environment of the skin, including, but not limited to, the mechanical environment of the wound. The devices, dressings, kits, and methods described herein may also control or regulate the mechanical environment to reduce scar and / or keloid formation. The mechanical environment of the skin may include stress, strain, or any combination of stress and strain. Control of the mechanical environment of the wound may be active or passive, dynamic (e.g., by applying an oscillatory stress), or static. The stresses and strains acting on the wound may involve layers of the skin, such as the outer stratum corneum, epidermis, and dermis, and underlying connective tissue layers, such as subcutaneous fat. The devices and methods described herein may shield the wound from its mechanical environment. The term "shield" is meant to encompass unloading the stresses experienced by the wound, and providing a physical barrier against contact, contaminants, and the like. The devices and methods described herein may shield the wound by unloading the wound and surrounding tissue from intrinsic and / or exogenous stresses. Thus, the devices and methods described herein may reduce the stresses experienced by the wound and surrounding tissue to levels lower than those experienced by normal skin and tissue. Unloading exogenous and / or intrinsic stresses in the vicinity of the wound may reduce the formation of scars, hypertrophic scars, or keloids.

[0070] The external mechanical environment of a cell can induce biological responses inside the cell and change cell behavior. Cells can sense and respond to changes in their mechanical environment using integrins, which are integral membrane proteins in the plasma membrane of the cell, and intracellular pathways. Intracellular pathways are initiated by receptors attached to the cell membrane and the cell membrane that can sense mechanical forces. For example, mechanical forces can trigger the secretion of cytokines, chemokines, growth factors, and other bioactive compounds that can increase or induce an inflammatory response. Such secretion can act within the cell that secretes them (intracrine), on the cell that secretes them (autocrine), on cells surrounding the cell that secretes them (paracrine), or at a distance from the point of secretion (endocrine). Intracrine interference can modify cell signaling, which in turn can modify cell behavior and biology, including recruitment of cells to the wound, proliferation of cells in the wound, and cell death in the wound. In addition, the extracellular matrix can be affected.

[0071] As described above, the wound healing process can be characterized in three phases: the early inflammatory phase, the proliferation phase, and remodeling. The inflammatory phase occurs immediately after injury and typically lasts from about 2 days to 1 week. Blood clotting occurs to stop blood loss, and factors are released to attract cells that can remove debris, bacteria, and damaged tissue from the wound. In addition, factors are released to initiate the proliferation phase of wound healing. In the proliferation phase, which lasts from about 4 days to several weeks, fibroblasts grow and build new extracellular matrix by secreting collagen and proteoglycans. At the end of the proliferation phase, fibroblasts can act to further contact the wound. In the remodeling phase, randomly oriented collagen is organized and crosslinked along skin tension lines. Cells that are no longer needed can undergo apoptosis. The remodeling phase can continue for weeks, months, or indefinitely after injury. Scars typically reach about 75-80% of normal skin's breaking strength about 6-8 weeks after injury. In general, scars typically have a triangular cross-section; that is, scars are usually smallest in volume near the skin surface (i.e., the stratum corneum and epidermis) and increase in volume as they progress into the deeper layers of the dermis.

[0072] There are three general possible outcomes for the wound healing process. First, normal scarring may result. Second, pathological increase in scar formation, such as formation of hypertrophic scar or keloid, may result. Third, the wound may not heal completely and become a chronic wound or ulcer. The devices, kits, and methods described herein can reduce the formation of any type of scar. In addition, the devices, kits, and methods described herein can be adapted for various wound sizes and different thicknesses of skin, for example, the devices may be configured for use in different areas of the body. In addition, the devices, kits, and methods described herein can be adapted to reduce scar formation in skin of any type, for example, body location, age, race, or condition.

[0073] Without wishing to be bound by any particular theory, the inventors believe that mechanical strain acting on a wound or incision early in the proliferative phase of the wound healing process may inhibit cell apoptosis, leading to significant accumulation of cells and matrix, and thus increased scarring or the production of hypertrophic scars. Given the fundamental similarity between hypertrophic scars and keloids in terms of excessive matrix formation, the inventors believe that the devices and methods described herein may also be useful in preventing and treating keloids by unloading or neutralizing at least a portion of the strain that may act on a wound or incision. This tensile strain may be exogenous and / or intrinsic strain, including, but not limited to, strain from the inherent tensile forces found in normal, unwounded skin tissue.

[0074] The devices, kits, and methods described herein may be for the treatment of a subject at a skin site, including but not limited to, for wound treatment or scar and / or keloid treatment, reduction, or prevention at or near a skin site, i.e., at or adjacent to a wound or treatment site on the subject's skin, by manipulating the mechanical or physical properties of the skin, or by shielding the skin from stress, and / or by controllably stressing or straining the epidermal and dermal tissue layers ("skin treatment devices"). According to a variation, manipulating the mechanical or physical properties may thereby modulate tensile or compressive stresses at the skin site. The stresses at the skin site may be reduced to levels at or below those experienced by normal skin and tissue. The stresses at the skin site may be increased to levels above those experienced by normal skin and tissue. Stress or strain may be applied to the surrounding tissue in one, two, or more directions to manipulate the intrinsic or extrinsic stresses at the skin site in one, two, or more directions. According to variations, the devices and methods described herein may reduce or otherwise manipulate the stress experienced by the skin and / or wound and surrounding tissue to treat a subject. The devices may also assist in preventing or reducing the occurrence of wound dehiscence.

[0075] The devices, kits, and methods described herein may be for the treatment of skin and / or the reduction or prevention of scarring and / or keloids by creating and / or maintaining a predetermined strain and / or a predetermined minimum or maximum strain in an elastic skin treatment device or dressing which is then affixed to the skin surface, e.g., using a skin attachment mechanism such as a skin adhesive, to transmit a generally planar (e.g., compressive) force from the device or dressing to the skin surface. "Prestrain," "prestrained," or "prestraining" as used herein refers to straining the device prior to application of the device to a subject.

[0076] The devices, kits, and methods herein may include a support, packaging, and / or applicator configured to maintain the pre-strained dressing in a strained configuration for a period of time after straining and prior to application to the skin of a subject. The devices and methods herein may include methods of making such pre-strained dressings.

[0077] According to one variation, the pre-strained, strain-shielded bandage assembly may be stored for a period of time after straining and prior to use. In some variations, the bandage may be configured to maintain a predictable and / or desired amount of tensile force for a predetermined period of time after initial strain. In some variations, the bandage may be configured to lose a predetermined maximum and / or minimum amount of tensile force (measured in the direction of tensile strain of the bandage) for one or more periods of time.

[0078] The desired time for application of the dressing to a subject may be when the dressing has a desired tensile force characteristic or range in its pre-strained, strain-shielded configuration. Such desired range may be selected to provide sufficient modulation of force on the skin to treat the skin while avoiding or minimizing disruptive irritation to the skin. As described herein, for a given dressing, different levels of stress or strain may be applied to skin at different locations and / or on different subjects. Also, different levels of force unloading may be desired for different locations on the skin of different individuals or subjects. Thus, different ranges of dressing force properties may be appropriate for different skin treatment applications.

[0079] Such desired force ranges may be selected based on a determination of the desired force characteristics to be applied to a particular subject, portion of skin, and / or for a particular skin treatment purpose. Such desired forces may be high enough to provide therapeutic mechanomodulation of the skin, yet low enough to prevent significant skin irritation.

[0080] The force properties of a pre-strained bandage may vary over time. An initial strain may be applied to the bandage, and the elastic material or other structure of the bandage has an initial tensile force property. The bandage may be maintained in a strained configuration at a particular strain level after it has been pre-strained for an initial period of time. During the initial period of time, the force properties of the elastic material may decrease, decay, or exhibit loss of force. After an initial predetermined period of time, the force properties of the elastic material may reach, decrease, or decay to a desired force level and / or range of force levels. The bandage elastic material force properties may remain within a desired range for at least a subsequent period of time. In some variations, the dressing material may have a modulus of elasticity in the range of about 1 MPa to about 15 MPa, sometimes about 1.5 MPa to about 6 MPa, and other times about 2 MPa to about 5 MPa, about 3 MPa to about 4 MPa, or about 3.5 MPa to 5 MPa, while having a peak load per width of maximum 0.6 strain of less than 3 N / mm, sometimes less than about 2.5 N / mm, sometimes less than 2 N / mm, sometimes less than 1 N / mm, sometimes less than about 0.75 N / mm, and other times less than about 0.6 N / mm, or less than about 0.5 N / mm. The peak load per width of maximum 0.6 strain may be at least about 0.35 N / mm, sometimes at least about 0.5 N / mm, and other times at least about 0.6 N / mm, 0.7 N / mm, 0.8 N / mm, 0.9 N / mm, or 1 N / mm. The material may be selected such that the material at a constant engineering strain of 20% is capable of maintaining an engineering stress of at least about 200 kPa, 250 kPa, 300 kPa, 400 kPa, or 500 kPa, 1,000 kPa, 1,500 kPa, 2,000 kPa, 2,500 kPa, 3,000 kPa, or more, for at least 8 hours with less than a 10% or 5% fluctuation or decrease in engineering stress.

[0081] According to an alternative embodiment, for example, the initial force or strain properties of the dressing may be selected so that a desired range of force values ​​occurs during which the rate of force loss is reduced and occurs over a longer period of time.

[0082] The initial strain and / or force level of the dressing may be selected so that the time of use falls within a desired time frame or period based on the rate at which the dressing loses force over time.

[0083] According to a variant, the dressing may be initially strained or overstressed to provide an initial force per unit width above that of the desired range upon application to the skin. According to a variant, the initial strain and resulting initial force per width of the dressing may be selected based on the desired final resulting force properties and / or the desired time frame for use of the dressing. Such initial strain levels may be, for example, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 100% or more. According to a variant, the initial force is above the desired force range. Such initial force levels may be, for example, about 25% or up to 25%, about 35% or up to 35%, about 50% or up to 50%, about 75% or up to 75% or more than the desired force upon application of the dressing. Such initial force levels may be, for example, but not limited to, 2-5 Lbf / inch, 1.54-3.85 Lbf / inch, 1.33-3.33 Lbf / inch, or 0.85-2.20 Lbf / inch.

[0084] According to a variant, the dressing may be initially strained or stressed to a desired strain or force level and configured to be maintained in the strained configuration for an initial time frame. According to a variant, the initial time frame may be, for example, one hour or more, one day or more, one week or more, or up to one month or more prior to application. According to a variant, the initial time frame may be one hour or more, one day or more, one week or more, or up to one month or more prior to final assembly or manufacturing in a preconditioning state of the material. Such a preconditioning state may strain the material at a constant strain or strain the material at various levels of strain.

[0085] According to some variations, the dressing may then be configured to maintain a desired minimum final force or force range for the duration of a subsequent predetermined time frame after the initial time frame. During the subsequent time frames, the device may be applied to the subject's skin for treatment. Such a desired force range may be about 0.5-1.0 Lbf / inch, 1.0-2.5 Lbf / inch, or about 1.6-2.1 Lbf / inch. The force loss during the subsequent time period may be up to 3%, up to 5%, up to 8%, up to 10%, up to 15%, up to 20%, up to 25%, or more. The duration of the subsequent time period may be, for example, 2 months or more, 3 months or more, 6 months or more, 12 months or more, 36 months or more, or 48 months or more.

[0086] The pre-strained dressing may then be coupled to a strain-retaining element for an initial period of time, and the strain-retaining element may remain on the dressing for a portion of a subsequent period of time until it is used.

[0087] According to variations, for example, the average initial force or strain properties of the dressing pre-strained at the time of manufacture (average may include or comprise, for example, an average per manufacturing lot, or a defined average within a given tolerance level) may be provided such that a desired range of average force values ​​occurs during which the average percentage loss of force is reduced and occurs over a longer period of time. In other variations, pre-straining begins at the point of use. In yet other variations, some of the pre-straining is performed at the point of manufacture, with additional straining or strain relaxation performed at the point of use. After pre-straining, the dressing may then be packaged, sealed, and sterilized for future use.

[0088] The initial average strain and / or force level of the dressing may be selected based on the average rate of loss of force of the dressing over time, so that the time of use falls within a desired time frame or period.

[0089] According to a variant, the dressing may be initially strained or overstressed to provide an average initial force per unit width above that of the desired range upon application to the skin. According to a variant, the average initial strain and resulting initial force per width of the dressing may be selected based on the desired final resulting force properties and / or the desired time frame for use of the dressing. Such average initial strain levels may be, for example, less than 20%, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, 100% or more. According to a variant, the average initial force is above the desired force range. Such average initial force levels may be, for example, about 25% or up to 25%, about 35% or up to 35%, about 50% or up to 50%, about 75% or up to 75% or more than the desired force upon application of the dressing. Such average initial force levels may be, for example, but not limited to, 2-5 Lbf / inch, 1.54-3.85 Lbf / inch, 1.33-3.33 Lbf / inch, or 0.85-2.20 Lbf / inch.

[0090] According to a variation, the dressing may be initially strained or stressed to a desired average strain or force level and configured to be maintained in the strained configuration for an initial time frame. According to a variation, the initial time frame may be one hour or more, one day or more, one week or more, or up to one month or more prior to application. According to a variation, the initial time frame may be one hour or more, one day or more, one week or more, or up to one month or more in a preconditioning state of the material prior to final assembly or manufacturing. Such a preconditioning state may strain the material at an average constant strain or strain the material at various levels of average strain.

[0091] According to some variations, the dressing may then be configured to maintain a desired minimum average final force or average force range for the duration of a subsequent predetermined time frame after the initial time frame. During the subsequent time frames, the device may be applied to the subject's skin for treatment. Such a desired average force range may be about 0.5-1.0 Lbf / inch, 1.31 Lbf / inch-1.41 Lbf / inch. The average force loss during the subsequent time period may be up to 3%, up to 5%, up to 8%, up to 10%, up to 15%, up to 20%, up to 25%, or more. The duration of the subsequent time period may be, for example, 2 months or more, 3 months or more, 6 months or more, 12 months or more, 36 months or more, or 48 months or more.

[0092] The pre-strained dressing may be bonded to a strain-maintaining element for an initial period during one or more manufacturing steps, and the strain-maintaining element may remain on the dressing until it is used, for a portion of a subsequent period during manufacturing, or during transportation or storage. EXAMPLES

[0093] Example I below illustrates the percent change in force per unit width of selected pre-strained dressings maintained at constant strain over a period of time under test conditions.

[0094] Example I In this example, five (5) dressings were strained at 40% and five (5) dressings were strained at 60%. The dressings were constructed from MED 82-5010-10 by NUSIL TECHNOLOGY LLC (Carpinteria, CA). A maximum of five particulates less than or equal to 0.020 inches per sheet and a maximum of five surface gels and / or bubbles less than or equal to 0.020 inches in size per sheet were present in the samples. The samples were initially 8 inches (+-0.02 inches) by 1 inch (+-1 inch) with a thickness of 0.010 inches. The samples had a durometer hardness value of about 50 (Shore A scale), a tensile strength of about 1,450 psi, an elongation of about 1,000%, and a specific gravity of about 1.16. Six (6 inch) centered gauge marks were added. The gage length of the 40% strain sample increases to 8.4 inches as strained. The gage length of the 60% strain sample increases to 9.6 inches as strained. The samples were mounted in a strained configuration in a sample fixture or clamp with a locking bar between the sample fixtures. The sample fixture was constructed from acrylic (PMMA) and coated with anti-skid tape. When tested, the ends of the sample fixture were attached to the grips of a tensile tester Chatillon Model TCD225 (50 LBF load cell). Measurements were then taken after releasing the locking bar. The samples were stored in the test laboratory at ambient laboratory temperature for the duration of the test. The tensile force of the dressings was measured at various time intervals. Figure 6 illustrates the percent loss of force over time for each dressing. The initial average post strain loss after 1 hour at 60% strain was about 30% and after 1 hour at 40% strain was about 25%. It was surprising to see that following the initial post-strain loss, the additional losses after the initial loss decreased at a slower rate, averaging about 15% over the two-year period (a total average loss of 45%).

[0095] In other embodiments, the maximum number of particles per sheet is 0.01 inches, 0.02 inches, , 0.040 inch, 0.050 inch, 0.07 inch, or 0.1 inch 1, 5, 10, 20, or 25 or more, with maximum size The maximum number of surface gels and / or bubbles may be 0.01 inches, 0.0 2 inch, 0.040 inch, 0.050 inch, or 0.07 inch, or 0.1 1, 5, 10, 20, or 25, or more, with a maximum size in inches In other variations, the dressing material may have a viscosity of from about Shore A 15 to about 90 , sometimes about Shore A35-75, and other times about Shore A50-60, or It may have a durometer hardness value of A50 to A75.

[0096] Example II below illustrates the percent change in force per unit width of selected pre-strained dressings maintained at constant strain over a period of time under test conditions.

[0097] Example II In this example, ten dressing membranes were strained at 45%. The dressing membranes were constructed from polyurethane by 3M (St. Paul, MN). The samples were initially 8 inches (+-0.02 inches) by 1 inch (+-1 inch) with a thickness of 0.002 inches. The samples had a tensile strength of about 2.2 lbs / in and an elongation of about 300%. Six inches (6 inches) of centered gauge marks were added. The gauge length of the 45% strain samples increased to 8.7 inches when strained. The samples were mounted in a strained configuration in a sample fixture or clamp with a locking bar between the sample fixtures. The sample fixture was constructed from acrylic (PMMA) and coated with anti-skid tape. When tested, the ends of the sample fixture were attached to the grips of a tensile tester Chatillon Model TCD225 (50 LBF load cell). Measurements were then taken after releasing the locking bar. The samples were stored in the test laboratory at ambient laboratory temperature for the duration of the test. The tensile strength of the dressing was measured at various time intervals.

[0098] Figure 9 illustrates the percent loss of force over time for each dressing. The initial average post-strain loss after 1 day at 45% strain was about 33%. Following the initial post-strain loss, it was surprising to see that the additional losses after the initial loss decreased at a slower rate, averaging about 12% (a total average loss of 45%) over the 13 day period.

[0099] FIG. 7 is a schematic illustration of the percent force loss over time of a variation of an elastic material of a dressing that is strained by a predetermined amount and held in a strained configuration over time. According to FIG. 7, the dressing and / or dressing material is held at a constant strain for a period of time. The initial strain may be selected to provide different percent force loss values ​​at a particular time. The percent force loss values ​​and force values ​​may vary for different initial strain levels and different materials. A curve plot for a particular dressing material may be determined, for example, as described with respect to Example I. As the force loss percentage increases, the force value decreases for a particular material or dressing, and / or the average force loss value decreases for a manufactured material or dressing lot that has been pre-strained by substantially the same amount. At time T0, the material is strained. During the initial time frame of T0-T1, the percent force loss of the material occurs at a more rapid rate than it occurs in subsequent periods or time frames, e.g., T1-T3, T1-T2, and / or T2-T3. Time frames T1-T3, T1-T2, and / or T2-T3 represent example time frames that may or may not be selected based on desired force properties for the dressing, desired time for use of the properties, and / or desired rate of loss of force. For example, a dressing may be pre-strained at the time of manufacture and then stored or transported for later use during defined time frames, e.g., T1-T2, T2-T3, and / or T1-T3.

[0100] FIG. 8 is a schematic illustration of force over time for a variation of an elastic material of a dressing that is strained by a predetermined amount and held in a strained configuration over time. According to FIG. 8, the dressing and / or dressing material is held at a constant strain for a period of time. The initial strain may be selected to provide different force values ​​at a particular time. The force values ​​and percent force value loss may vary for different initial strain levels and different materials. A curve plot for a particular dressing material may be determined, for example, as described with respect to Example I. As the force loss percentage increases, the force value decreases for a particular material or dressing and / or the average force loss value decreases for a manufactured material or dressing lot that has been pre-strained by substantially the same amount. At time T0, the material is strained. During the initial time frame T0-TA, the material loses force at a more rapid rate than it does in subsequent periods or time frames, e.g., TA-TC, TA-TB, and / or TB-TC. Time frames T0-TA, TA-TB, and / or TB-TC represent example time frames that may or may not be selected based on desired force properties for the dressing, desired time for use of the properties, and / or desired rate of loss of force. For example, a dressing may be pre-strained at the time of manufacture and then stored or transported for later use during a defined time frame, e.g., TA-TB, TB-TC, and / or TB-TC.

[0101] According to some variations, the elastic device may be strained at different strain values ​​during preconditioning.

[0102] Variations of the support devices, strain shields, or packaging herein may or may not operate as applicators, where one or more elements of the packaging may be used to position and / or apply the dressing to the skin of a subject. Variations of the applicator devices with attached dressings may be pre-strained at the time of manufacture and releasably secured in the pre-strained configuration using a lock or restraint attached to the applicator, such as a locking bar or flexible restraint or strut. Examples of applicators that may be used in conjunction with locks or restraints include those described in co-pending U.S. Patent Publication No. US 2011 / 152,738, entitled "Devices and Methods For Dressing Applicators," which is incorporated herein by reference in its entirety.

[0103] The devices, kits, or methods described herein may include supports, packaging, applicators, and / or other devices that may contain, hold, or support a pre-strained dressing, may be used to prepare the dressing for application, may be used to deliver, orient, or apply the dressing, may be used to maintain the dressing in a stressed or strained configuration, may be used to stress or strain the dressing to a desired degree or within a window of a desired amount, degree, or percentage of strain, and / or may be used to apply pressure to the wound, incision, or other treatment site, for example, to provide additional treatment to the skin, wound, incision, and / or other treatment site during or after application of the dressing. According to variations, the support device, packaging, or applicator is configured to provide support for the dressing before and / or during application of the dressing to a subject. The dressing support structure described herein may comprise a structure that interfaces with, supports, and / or is attached to a back surface of a dressing that is to be applied to a subject, whether directly or indirectly. The dressing support may optionally comprise a structure that interfaces with, supports, and / or is attached to a front surface of a dressing that is to be applied to a subject, whether directly or indirectly.

[0104] The support structure may further comprise, at least in part, a material or structure that is more rigid or less flexible than the dressing to be applied to the subject. The support structure may comprise, for example, one or more elements or sections that allow flexibility relative to adjacent elements or sections. Such materials may include, for example, plastics, such as PVC or acrylic, or paperboard. The elements or sections may be laminates of materials such as solid bleached sulfate paperboard with layers of flexible materials, such as silicone, polyurethane, low density polyethylene, rubber materials, or transfer adhesive with or without a carrier, between layers of paperboard. The material may also be metal. Such support structures may be constructed from a single substrate, a laminate, or multiple elements bonded together and / or to the dressing. According to some variations, the support, packaging, or applicator is more rigid or supports the dressing in at least one direction, while being flexible in at least one direction to provide a more conforming application to the curved or shaped skin surface of the subject, or to allow the dressing to be curved or shaped to which it is applied. According to some variations, the support, packaging, or applicator may comprise sections of a relatively more rigid material flexibly bonded to adjacent sections to provide flexibility to allow molding of the packaging / applicator and / or dressing while providing sufficient support for the dressing during application. According to some variations, the sections are bonded to adjacent sections using a flexible material such as a low density polyethylene (LDPE) material, or a composite of an adhesive and a thinner, more flexible substrate. Alternatively, the sections may be formed as structures by manufacturing a substrate with cutouts, slots, grooves, creases, or other openings, or variations in thickness of the substrate at different locations.

[0105] The support, packaging, or applicator, and / or elements thereof may have a linear, curved, or otherwise varied profile for direct or indirect interfacing contact with the subject's body. The support, packaging device, applicator, and / or elements thereof may be selected or configured to closely match a portion of the subject's body profile to which the skin treatment device is to be attached. The support, packaging device, applicator, or elements thereof may be selected or configured to have a profile that is desired for a particular body location or a profile where the skin treatment device is to be placed on the subject's skin. The support, packaging device, applicator, and / or elements or sections thereof may be curved, bendable, flexible, bendable, malleable, deformable, moldable, or movable to provide alternative shapes or profiles of the attached dressing. They may be relatively curved, bendable, flexible, malleable, bendable, deformable, moldable, or movable in at least one direction while being more rigid in another direction.

[0106] Some wound dressings have a backing, adhesive liner, and / or packaging that is removed prior to application of the wound dressing. Many existing dressings can be difficult to orient and apply and may have a tendency to fold and adhere to themselves. According to some variations, the backing, support, packaging, and / or applicator may provide structural support or stability for the dressing while or after the adhesive liner is released. The packaging and / or applicator may also provide structural support or stability for the dressing as it is oriented and / or applied to the skin of a subject. According to some variations, the assembly may be constructed to avoid folding or bending the dressing to such an extent that the adhesive on the dressing sticks to itself. According to some variations, the packaging or applicator is configured to be used with one hand to orient and / or apply the device to the skin of a subject. For example, in some situations, especially when longer or larger dressings are used, the packaging or applicator provides structural support for the dressing so that the user can effectively hold, manipulate, and / or apply the prepared dressing with one hand. According to one variation, the applicator and / or packaging may be sufficiently supportive or rigid to hold the dressing's shape so that it is easy to manipulate. According to a variation, the applicator may be sufficiently wider and / or longer than the dressing, or have a sufficiently large area so that it can provide for sterile application and / or one-handed application. According to a variation, a support structure is provided for the dressing. According to a variation, a margin is provided as part of the support structure between the dressing or dressing adhesive and one or more edge portions of the support structure. Such margin provides a supported edge or area for gripping or manipulating the dressing or its carrier without forcing or creating a higher probability of contact with the adhesive.

[0107] The support, packaging assembly, and / or applicator device may include tension-maintaining structures configured to assist in maintaining the dressing in the prestrained configuration, and some acceptable level of strain reduction may occur during storage of a prestrained device coupled to the support, packaging, or applicator for a period of time.

[0108] According to a variation, the tension-maintaining structure may comprise a first attachment portion configured to be releasably attached to the bandage and a second attachment portion configured to be releasably attached to the bandage, and the tension-maintaining structure may be configured to maintain a previously applied separation force between the first and second attachment portions and to maintain a strain in the bandage attached to the first and second attachment portions. An elastic bandage may be configured to be releasably attached to the bandage and the first and second attachment portions of the packaging assembly and may include the attachment structure or may be integral with the attachment structure of the packaging device, applicator, or tensioning member.

[0109] A variety of attachment, coupling, locking, latching, or detent mechanisms may be used to maintain the dressing and / or packaging, applicator, or tensioning device in various configurations, including, but not limited to, various pre-strained or strained configurations. By coupling, attaching, or locking the packaging, applicator, tensioning device, or dressing in a strained position, a predetermined strain and / or force characteristic for a given dressing may be achieved. The predetermined amount of strain may be based on the desired strain or force characteristic to be applied by the dressing to the skin after application. After application to the skin, the strain may be relieved by a certain amount or percentage.

[0110] The support, packaging device, and / or applicator, or dressing or dressing assembly may include any attachment structure used to attach or couple the support, packaging, and / or applicator to the dressing or dressing assembly. The attachment features or structures of the dressing device may be integral with or include any of the attachment structures of the support, packaging, applicator, and / or elements thereof or structures corresponding to the attachment structures. Such releasable attachment structures may include, but are not limited to, attachment sheets, adhesives, pockets and tabs, hook-and-loop mechanisms, hooks, angled bars, adhesives, pegs, rip cords, towel rail configurations, sliding pins, friction locks, cam locks, vacuum or suction devices, snap connectors, carpet tacks, press-fit or other connections, severable, tearable, or otherwise disruptable structures that allow removal of the dressing from the support, packaging, and / or applicator.

[0111] According to some variations, the packaging and / or applicator provide a release mechanism for separating the applied dressing from the support, packaging, and / or applicator after the dressing has been applied to the skin. The release mechanism may be configured to facilitate separation, release, removal, or detachment of the attachment structure that attaches the dressing to the support, packaging, applicator, or portions thereof, including, but not limited to, the separation devices and methods described herein. The dressing release may comprise, for example, a high tack removable adhesive, such as a pressure sensitive adhesive. For example, a silicone dressing may have an acrylic pressure sensitive adhesive that does not permanently bond to the silicone. The dressing release may comprise, for example, a tear strip, one or more perforations or pre-creased areas, a cutting member, or a tearable material. The release mechanism may also include, but is not limited to, a pivoting, rolling, rocking, or sliding feature associated with or coupled to the attachment structure. They may be self-releasing latches or spring members. They may be actuated when a pressure member is applied to the skin treatment device prior to removing the applicator. They may be actuated manually. The mechanisms may include, for example, levers, latches, locking members, spring members, or other mechanisms such as cutters or ripcords, or other structures or features to facilitate tearing, cutting, or separation of the attachment structures or elements.

[0112] According to some variations, the applicator may further be used to help reduce bleeding, for example, by allowing the application of a compressive force using a support structure during or after the device is applied. One or more hemostatic or coagulant agents may be applied to or otherwise integrated with the dressing to help reduce bleeding. Potential agents include chitosan, calcium-loaded zeolite, microfibrillar collagen, cellulose, anhydrous aluminum sulfate, silver nitrate, potassium alum, titanium dioxide, fibrinogen, epinephrine, calcium alginate, poly-N-acetylglucosamine, thrombin, clotting factors (e.g., II, VII, VII, X, XIII, von Willebrand factor), coagulant promoters (e.g., propyl gallate), antifibrinolytic agents (e.g., epsilon aminocaproic acid), and the like. In some variations, the agents may be lyophilized and integrated into the dressing and activated upon contact with blood or other fluids. In some further variations, an activating agent may be applied to the dressing or treatment site before the dressing is used on the subject. In still other examples, a hemostatic agent may be applied separately and directly to the wound before application of the dressing or after application to the dressing via a catheter or tube. The device may also comprise one or more other active agents that may be useful in assisting some aspect of the wound healing process. For example, the active agent may be a pharmaceutical compound, a protein (e.g., a growth factor), a vitamin (e.g., vitamin E), or a combination thereof. Further examples of such agents may include, but are not limited to, various antibiotics (including, but not limited to, cephalosporins, bacitracin, polymyxin B sulfate, neomycin, polysporin), antiseptics (iodine solution, silver sulfadiazine, chlorhexidine, etc.), antifungals (nystatin, etc.), antiproliferatives (sirolimus, tacrolimus, zotarolimus, biolimus, paclitaxel), growth factors (vascular endothelial growth factor (VEGF), etc.), and other therapies (e.g., botulinum toxin).Of course, the device may comprise more than one drug or agent, and the device may deliver one or more drugs or agents.

[0113] In some variations, a dressing is provided that comprises an elastic member, e.g., a sheet structure (e.g., including a silicone polyurethane, a TPE (thermoplastic elastomer), a synthetic rubber, or a copolyester material), that comprises an upper surface, a lower surface, a first edge, a second edge opposite the first edge, and one or more adhesive regions. The dressing may further comprise a first release liner that is releasably attached to the adhesive region or regions. The adhesive region may comprise a pressure sensitive adhesive. The dressing may be tapered or otherwise shaped to reduce skin tension at the edges. The dressing may have modified, reduced adhesive, or no adhesive near its edges to reduce skin tension at the edges. Portions of the dressing may be unstrained, thereby reducing strain in an area of ​​the skin to which the dressing is applied. In some specific examples, the unstrained area or areas are found between the edge of the dressing and the strained area. In some further embodiments, the unstrained areas are confined to this area and are not found among the strained areas of a single dressing during application or use, hi still further embodiments, the unstrained areas are confined to areas along the edges of the dressing that intersect the strain axis of the strained areas, rather than areas along edges of the dressing that are generally parallel to the strain axis.

[0114] The elastic material of the dressing may comprise a single layer of material or multiple layers of the same or different materials. The material may have any of a variety of configurations, including solid, foam, lattice, or woven configurations. The elastic material may be a biocompatible polymer, including, for example, silicone, polyurethane, TPE (thermoplastic elastomer), synthetic rubber, or copolyester materials. The thickness of the polymer sheet, e.g., the polymer sheet or shape memory polymer sheet, may be selected to provide a dressing with sufficient load capacity to achieve a desired recoverable strain and to prevent an undesirable amount of incremental deformation of the dressing over time. In some variations, the thickness across the dressing is not uniform, e.g., the thickness across the dressing may be varied to change the stiffness, load capacity, or recovery strain at selected orientations and / or locations. The elastic material of the exemplary bandage may have a thickness within the range of about 50 microns to 1 mm or more, about 100 microns to about 500 microns, about 120 microns to about 300 microns, or in some variations, about 200 microns to about 260 microns. Exemplary bandages may have edge thicknesses of about 500 microns or less, 400 microns or less, or about 300 microns or less, and are less likely to present a risk of skin separation from inadvertent lifting when inadvertently touched by clothing or objects. In some variations, the bandage may be tapered near the edges to reduce thickness. Tapered edges may also mitigate peak tensile forces acting on skin tissue adjacent the adhesive edges of the bandage. This may or may not reduce the risk of skin blistering or other tension-related skin trauma. In other variations, the edges of the bandage may be thicker than the center of the bandage. It is hypothesized that in some configurations, a thicker dressing edge may provide a relative inward shift in the location of peak tensile forces acting near the dressing edge compared to a dressing of uniform thickness. The elastic material may have a load per width of at least 0.35 Newtons / mm, or a load per width of at least 0.25 Newtons / mm, or a load per width of at least 0.10 Newtons / mm when the dressing is applied to the skin.The elastic material may have a load per width of about 2 Newtons / mm, about 1 Newton / mm, about 0.7 Newtons / mm or less, or about 0.5 Newtons / mm or less when the dressing is applied to the skin. The system elastic material may have a load per width that does not decrease from 0% to 60% engineering strain, a load per width plot that increases linearly from 0% to 60% engineering strain, or a load per width plot that is not convex from 0% to 60% engineering strain. The elastic material may comprise an adhesive configured to maintain a substantially constant stress within a range of 200 kPa to about 500 kPa for at least 8 hours when strained to about 20% to 30% engineering strain and attached to a surface. The dressing may comprise an adhesive on the elastic material configured to maintain a substantially constant stress within a range of 200 kPa to about 400 kPa for at least 8 hours when strained to about 20% to 30% engineering strain and attached to a surface. The substantially constant stress may vary by less than 10% over at least 8 hours, or by less than 5% over at least 8 hours.

[0115] The depicted dressings may have a generally rectangular configuration with a size of about 160 mm to about 50 mm, although in other variations the dressings may have any of a variety of lengths and widths and may comprise any of a variety of other shapes. Also, the corners of the dressings may be angular or rounded, for example. The length and / or width of exemplary dressings may range from about 5 mm to about 1 meter or more, in some variations from about 20 mm to about 500 mm, in other variations from about 30 mm to about 50 mm, and in still other variations from about 50 mm to about 100 mm. In some variations, the ratio of the dressing's maximum dimension (e.g., its length) to the orthogonal dimension to its maximum dimension (e.g., width), excluding the dressing's minimum dimension (e.g., thickness), may be in the range of about 1:1, about 2:1, about 3:1, about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, about 10:1 or greater. In some variations, the strain axis of the dressing in use may be oriented relative to the maximum dimension or relative to the orthogonal dimension to the maximum dimension. In some variations, the final compressive stress and strain imposed on the skin by the elastic material may be the result of a dynamic equilibrium between the tensile stress in the skin and the elastic material of the dressing. The elastic material and adhesive regions may be configured to be applied to a skin location such that when the bandage is stretched to a particular tension and then adhered to a skin location, the tensile stress in the bandage is transferred to the skin location to compress the tissue directly beneath the bandage along an axis tangential to the skin surface, and the stress and strain imposed on the skin location has a net or resulting orientation, or with a similar axis to the orientation, or axis of the tensile stress in the bandage, which axis is also approximately tangential or planar to the outer surface of the elastic material and / or the skin location. The tension in the bandage will relax to a tension level that maintains equilibrium with the increased tension in the skin adjacent the bandage. Application of the bandage to a skin location may involve placement of the bandage without overlapping or wrapping over itself, for example, only adjacent regions of the bandage are interconnected and non-adjacent regions of the bandage are not interconnected.The actual amount of stress and strain imposed on the skin may vary, for example, depending on the particular person, skin location, thickness or various mechanical properties of the skin layers (e.g., epidermis, dermis, or underlying connective tissue), and / or the extent of existing scarring. In some further variations, the skin treatment dressing may be selected or configured for use at specific body locations, such as the scalp, forehead, cheeks, neck, upper back, lower back, abdominal region, upper torso (including but not limited to breasts), shoulders, upper arms, forearms, palmar regions, dorsum of hands, fingers, thighs, lower legs, dorsal or plantar surfaces of feet, and / or toes. Where applicable, some body regions may be further delineated into anterior, posterior, medial, lateral, proximal, and / or distal regions, e.g., arms and legs.

[0116] The dressing may be configured to impose a skin strain within the range of about 10% or less to about 60% or more, in other configurations about 15% to about 50%, and in still other configurations about 20% to about 30% or about 40%. To achieve the desired degree of skin strain, the dressing may be configured to undergo an elastic tensile strain within the range of about 20% to about 80% or more, sometimes about 30% to about 60%, and other times about 40% to about 50% or about 60%. The dressing may comprise any of a variety of elastic materials, including, but not limited to, silicone, styrene block copolymers, natural rubber, fluoroelastomers, perfluoroelastomers, polyether block amides, thermoplastic elastomers, thermoplastic polyurethanes, polyisoprene, polybutadiene, and the like. Exemplary dressing materials may have a Shore A durometer hardness within the range of about 20 to about 90, about 30 to about 80, about 50 to about 80. An exemplary dressing was constructed from MED82-5010-05 (MED 4050) by NUSIL TECHNOLOGY LLC (Carpinteria, Calif.). Other examples of suitable materials are described in U.S. Application Serial No. 11 / 888,978, previously incorporated by reference in its entirety. Other exemplary materials are manufactured by DUPONT TM LIVEO TMIncludes QP1-60 silicone elastomer (DuPont; Wilmington, Del.) or LAIMEISI silicone elastomer (Shenzhen Laimeisi Silicone Industry; Shenzhen, China).

[0117] When the dressing is applied to a skin location and allowed to at least partially recover to its base configuration, the recovery or equilibrium level of strain in the dressing may be within the range of about 10% or less to about 60% or more, in other configurations about 15% to about 50%, and in still other configurations about 20% to about 30% or about 40%. The ratio between the initial engineering tensile strain applied on the dressing prior to recovery and the resulting engineering compressive strain in the skin may vary depending on the type and location of the skin, but in some embodiments may be about 2:1. In other embodiments, the ratio may be within the range of about 4:1 to about 5:4, about 3:1 to about 5:3, or about 5:2 to about 2:1. These skin strain characteristics may be determined relative to a reference location, e.g., an anatomical location, on the body or body part to facilitate reproducible measurements. A particular degree of strain may be characterized as either engineering strain or true strain, but may or may not be calculated based on or converted from other types of strain (e.g., the strain may be based on 45% engineering strain that is converted to true strain).

[0118] In some further variations, one or more properties of the elastic material may correspond to different features on the stress / strain curve of the material. For example, the engineering and true stress / strain curves for one specific embodiment of a dressing comprise a material that exhibits an engineering stress of about 1.2 MPa at about 60% engineering strain during the initial straining period. In other embodiments, the engineering stress during the initial straining period may be in the range of about 900 kPa to about 2.5 MPa, about 1 MPa to about 2.2 MPa, about 1 MPa to about 2 MPa, about 1.1 MPa to about 1.8 MPa, about 1.1 MPa to about 1.5 MPa, or about 1.2 MPa to about 1.4 MPa. When unloading or removing stress from the dressing, the material may be configured with an engineering stress of about 380 kPa at about 40% engineering strain, although in other embodiments, the engineering stress during unloading of the material to about 40% strain may be in the range of about 300 kPa to about 700 kPa, about 325 kPa to about 600 kPa, about 350 kPa to about 500 kPa, or about 375 kPa to about 425 kPa. When unloading the material to about 30% engineering strain, the material may exhibit an engineering stress of about 300 kPa, although in other embodiments, the engineering stress during unloading of the material to about 30% strain may be in the range of about 250 kPa to about 500 kPa, about 275 kPa to about 450 kPa, about 300 kPa to about 400 kPa, or about 325 kPa to about 375 kPa. When unloaded to about 20% engineering strain, the material may have an engineering stress of about 100 kPa, although in other embodiments the unloading engineering stress at about 20% may be in the range of about 50 kPa to about 200 kPa, about 75 kPa to about 150 kPa, or about 100 kPa to about 125 kPa. According to some variations, the thickness of the material may be more or less depending on certain factors, and the engineering stress may be considered as well, i.e., for example, the engineering stress increases with thinner material.In some embodiments, the material may be configured to achieve a specific range or level of engineering stress at least at each of the defined engineering strain levels described above, while in other embodiments, the material may be configured for lower levels of maximum engineering strain during initial straining, e.g., up to about 30% or about 40%, or for higher maximum engineering strain and higher engineering stress during initial straining, e.g., greater than 60% engineering strain.

[0119] In some embodiments, a portion of the stress / strain curve may have a particular shape. For example, for a particular level of maximum strain at the time of initial straining, the load curve may be approximately linear on the corresponding true stress / strain curve. In embodiments using the dressings described herein, the load curve had an approximately linear configuration up to about 45% true strain. In other embodiments, the configuration may be linear only along a portion of the load curve, or may be curvilinear along the entire load curve. If the load curve is nonlinear, the load curve may be convex, concave, or both. Also, in some embodiments, the tangent to the load curve (i.e., the line between the two triangles) may also be approximately colinear.

[0120] In some variations, the elastic material may comprise a material having a modulus of elasticity E of at least about 1 MPa, about 1.5 MPa, about 2 MPa, about 2.5 MPa, about 3 MPa, about 3.5 MPa, about 4 MPa, about 5 MPa, about 6 MPa, about 7 MPa, about 8 MPa, about 9 MPa, about 10 MPa, about 11 MPa, about 12 MPa, about 13 MPa, about 14 MPa, or at least about 15 MPa or more. The material modulus of elasticity E may be about 20 MPa, about 15 MPa, about 10 MPa, about 9 MPa, about 8 MPa, about 7 MPa, about 6 MPa, or about 5 MPa, or less than about 4 MPa.

[0121] In addition to the absolute stress levels at a certain strain level, as described above, materials may also be characterized in terms of the ratio between a) the stress to achieve a particular strain during loading and b) the stress at the same strain during unloading. For example, a material may have a ratio of at least 4:1 to about 3:2 at each of the 20%, 30%, and 40% strain levels, although in other examples, a material may exhibit these ratios only at the 20%, 30%, or 40% strain levels, or at both 20% and 30% but not 40%, or at both 30% and 40% but not 20%. In other examples, the ratio at one, some, or all of the strain levels may be within the range of about 3:1 to about 2:1, or about 5:2 to about 2:1.

[0122] In some examples, the elastic material of the dressing may be configured under test conditions to achieve a stable level of stress at a constant strain, e.g., the material exhibits a limited amount of stress relaxation over a particular period of time and at a particular level of strain. The period may be at least about 8 hours, about 12 hours, about 18 hours, about 24 hours, about 36 hours, about 48 hours, about 72 hours, about 4 days, about 5 days, about 6 days, or about 1 week or more. The level of strain may be about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, or about 80% or more. The stress of the exemplary dressing over various time curves may be configured to maintain an engineering stress of about 300 kPa at about 30% engineering strain without significant deviation for a period of about 1 hour, about 2 hours, about 3 hours, about 4 hours, about 5 hours, about 6 hours, about 7 hours, or about 8 hours or more. The stresses at 10% strain, 20% strain, and 40% can be lower or higher.

[0123] In some variations, the elastic material or dressing may be configured under test conditions to maintain a certain minimum level of stress when held at a certain strain for a certain period of time. In an example to assess the ability of the backing material to maintain stress and strain on the skin over time, the engineering strain was measured while each backing material was subjected to a tensile strain of 60% at a rate of 100 microns per second, held for 10 minutes, and then reduced to a strain of 30% at a rate of 100 microns per second and held for 9 hours. For example, an exemplary dressing is capable of maintaining an engineering stress level of about 350 kPa at an engineering strain of 30%. In some other embodiments, the minimum level of stress may be about 100 kPa, about 120 kPa, about 140 kPa, about 160 kPa, about 180 kPa, about 200 kPa, about 220 kPa, about 240 kPa, about 260 kPa, about 280 kPa, about 300 kPa, about 320 kPa, about 340 kPa, about 360 kPa, about 380 kPa, about 400 kPa, about 420 kPa, about 440 kPa, about 460 kPa, about 480 kPa, about 500 kPa, about 600 kPa, about 700 kPa, about 800 kPa, about 900 kPa, or about 1,000 kPa or more. The level of constant strain may vary in other configurations, with levels of about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, or about 80%. The period over which the dressing is able to maintain the stress level may be at least about 2,000 seconds, about 3,000 seconds, about 4,000 seconds, about 5,000 seconds, about 6,000 seconds, about 7,000 seconds, about 8,000 seconds, about 9,000 seconds, about 10,000 seconds, about 20,000 seconds, about 30,000 seconds, about 40,000 seconds, about 50,000 seconds, about 60,000 seconds, about 70,000 seconds, about 24 hours, about 36 hours, about 48 hours, about 72 hours, about 4 days, about 5 days, about 6 days, about 7 days, about 10 days, about 2 weeks, about 1 month, or more. In some variations, the dressing, elastic material, and / or adhesive material is configured to exhibit less than about a 15% change in stress or strain level over a particular period of time when applied to a skin surface or test surface.In other examples, the degree of change may be about 12%, about 10%, about 8%, about 6%, about 5%, about 4%, about 3%, or about 2%, or less. The stress or strain may be engineering stress or strain and / or true stress or strain. In some variations, the dressing comprises an elastic sheet structure (e.g., a silicone sheet) having an upper surface, a lower surface, a first edge and a second edge opposite the first edge, and one or more adhesive regions. The dressing may further comprise a first release liner releasably attached to the adhesive region or regions. The adhesive region may comprise a pressure sensitive adhesive. The dressing may be tapered or otherwise shaped to reduce skin tension at the edges. The dressing may have modified, reduced adhesive, or no adhesive near its edges to reduce skin tension at the edges. A portion of the dressing may be unstrained, thereby reducing strain in an area of ​​skin to which the dressing is applied. In some specific examples, the unstrained area or areas are found between the edge of the dressing and the strained area. In some further examples, the unstrained areas are limited to this area and are not found between the strained areas of a single dressing during application or use. In still further examples, the unstrained areas are limited to areas along the edges of the dressing that intersect the strain axis of the strained areas, rather than areas along the edges of the dressing that are generally parallel to the strain axis.

[0124] The adhesive used to attach the dressing to the skin may be a pressure activated adhesive (PSA), such as, for example, silicone, acrylic, styrene block copolymer, vinyl ether, nitrile, or other PSA. In other variations, non-pressure sensitive adhesives may be used, including, but not limited to, heat or light cured adhesives. Pressure sensitive adhesives may be made, for example, from polyacrylate-based, polyisobutylene-based, silicone-based pressure sensitive adhesives, and the like. The T-peel release force and blunt probe tack force of the adhesive may be measured by standardized test methods such as ASTM D1876 and ASTM D2979, or other suitable methods. In some variations, the T-peel release force or blunt probe tack test value of the adhesive is configured to maintain a load of at least about 50 mPa / mm for at least about 24 hours, about 48 hours, about 72 hours, about 1 week, about 2 weeks, about 3 weeks, about 4 weeks, or more. In other variations, the load may be at least about 75 mPa / mm, about 100 mPa / mm, about 125 mPa / mm, or at least about 150 mPa / mm for a particular period of time. The degree of adhesion (e.g., as measured by T-peel release force or blunt probe tack test values) may vary depending on the degree of strain applied on the skin or incision site, and in some variations, these periods may be based on an average skin strain of about 10%, about 20%, about 30%, about 40%, or about 50% or more. In some variations, the adhesive may have a T-peel release force of at least about 150 kg / m, about 160 kg / m, about 170 kg / m, about 180 kg / m, about 190 kg / m, about 200 kg / m, about 210 kg / m, about 220 kg / m, about 230 kg / m, about 240 kg / m, about 250 kg / m, about 260 kg / m, about 270 kg / m, about 280 kg / m, about 290 kg / m, about 300 kg / m, about 310 kg / m, about 320 kg / m, about 330 kg / m, about 340 kg / m, about 350 kg / m, about 400 kg / m, about 450 kg / m, or at least about 500 kg / m, or more.In some further variations, the T-peel release force may be about 1,000 kg / m, about 900 kg / m, about 800 kg / m, about 700 kg / m, about 600 kg / m, about 500 kg / m, about 400 kg / m, or about 300 kg / m or less. The adhesive may have a blunt probe tack test value of at least about 0.50 kg, about 0.55 kg, about 0.60 kg, about 0.65 kg, about 0.70 kg, or about 0.75 kg, or more, and may be about 1 kg, about 0.9 kg, about 0.8 kg, about 0.7 kg, or about 0.6 kg or less. The T-peel release force and blunt probe tack force may be measured by standardized test methods such as ASTM D1876 and ASTM D2979, or other suitable methods. Other features or variations of this device are described in U.S. Application No. 11 / 888,978, filed Aug. 3, 2007, which is incorporated herein by reference in its entirety.

[0125] The release liner, which protects the skin adhesive prior to application, may comprise any of a variety of materials, including both opaque and transparent materials. The release liner may comprise mylar or paper, or any other material that has reduced adhesion to the adhesive material of the device. In variations in which the device has multiple separate adhesive regions, a separate release liner may be provided for each region, or several regions may be covered by the same release liner.

[0126] The dressing packaging device, dressing support, and / or dressing applicator may also include a tensioning device configured to stress and / or strain the dressing prior to application to a subject. The device may be used to apply and / or maintain strain on the dressing.

[0127] 1A, dressing 110 is shown in a first configuration in which it is relatively unstrained. Dressing 110 may comprise an elastic sheet 160, such as a silicone sheet or other elastic material as described herein, with one or more adhesive regions comprising a layer of skin adhesive 140. Adhesive 140 may be applied prior to straining dressing 110 as shown in FIG. 1A, or after straining dressing 110. The adhesive used may be, for example, a suitable pressure activated adhesive (PSA) or non-pressure sensitive adhesive.

[0128] The dressing 110 may be bonded in an unstrained configuration (FIG. 1A) at its edges or sides 105, 106 with a high tack adhesive to the outer surface 132 of the support structure 130 at the sides 135, 136 of the support structure 130. An adhesive 125 may be applied between the sides 135, 136 of the support structure 130 where the dressing 110 should be attached to the inner surface 131 of the support structure 130. The adhesive 125 may be continuous or discontinuous. Other attachment structures as described herein may additionally or alternatively be used to attach the dressing 110 in the strained configuration to the support structure 130. The dressing 110 may be strained by pulling the edges or sides 135, 136 apart, with or without pushing a peak or central region 170 of the support structure 130 towards the dressing 110, straightening the support structure 130, and applying pressure to the dressing 110 against the adhesive 125 to secure the dressing in a stressed configuration. For example, clamps may be attached to the support structure 130 at opposing sides 135, 136 and then pulled apart to strain the dressing and straighten the support structure 130.

[0129] The support structure 130 and adhesive 125 (or other attachment structure) maintain the dressing 110 in its strained configuration as shown in Figures 1B and 1C. A skin adhesive layer 140 may be applied to the top surface 111 of the dressing 110, and a removable liner 150 is placed over the adhesive layer 140. This process thus forms a prestrained dressing 110 with a pre-attached, unstrained adhesive layer 140, although in other variations, the adhesive layer 140 may be applied prior to the prestraining process, thereby forming a prestrained dressing 110 with a prestrained adhesive layer 140. In some variations, the removable liner 150 comprises an elastic material that may be adhered to the adhesive layer 140 and dressing 110 prior to straining, and then prestrained along with the adhesive layer 140 and dressing 110, as opposed to traditional release liners for adhesive dressings that comprise paper or polymeric films. In other variations, the adhesive may be pre-applied to the release liner and then the combined release liner and adhesive layer is then attached to the dressing.

[0130] In use, the adhesive liner 150 may be removed and the dressing 110 may be applied to the surface of the skin of a subject. The support structure 130 may then be removed from the dressing 110, and in response, the stress or strain of the dressing will strain the skin and / or apply a compressive force to the skin and / or compressively strain the skin, thereby treating the skin. The liner 150 may further provide support, at least in part, to maintain the strain in the dressing 110.

[0131] The support structure 130 may be removed from the dressing 110 by peeling the support structure 130 from the dressing 110, where the adhesive force between the dressing 110 and the support structure 130 is less than the adhesive force between the dressing 110 and the skin to which it is applied. Alternatively, the dressing 110 may include a release mechanism as described further herein, for example, as described with respect to Figures 3A-3I.

[0132] 2A, the dressing 210 is shown in a first configuration in which it is relatively unstrained. The dressing 210 may comprise, for example, an elastic sheet, such as a silicone sheet or other elastic material as described herein, in which one or more adhesive regions comprise a layer of skin adhesive 240. The adhesive used may be, for example, a suitable pressure-activated adhesive (PSA) or non-pressure sensitive adhesive. The dressing 210 may be bonded at its edges or sides 205, 206 with a high tack adhesive 220 to the inner surface 231 of the support structure 230 at its sides 235, 236. A relatively continuous layer of high tack adhesive 220 may further be applied on the inner surface 231 between the sides 235, 236 of the support structure 230, where the dressing 210 should be attached to the inner surface 231 of the support structure 230. For example, other attachment structures as described herein may additionally or alternatively be used to attach the bandage 210 in the strained configuration to the support structure 230. The bandage 210 may be strained by pulling apart edges or sides 235, 236 of the support structure 230, straightening the support structure 230, and applying pressure to the bandage 210 against the adhesive 220. For example, clamps may be attached to the support structure 230 at opposing edges 235, 236 and then pulled apart to strain the bandage 210 and straighten the support structure 230. The support structure 230 and adhesive 220 (or other attachment structures) may maintain the bandage 210 in its strained configuration as shown in FIG. 2B. A skin adhesive layer 240 may be applied to the top surface 211 of the bandage 210, and a removable liner 250 is placed over the adhesive layer 240. The adhesive liner 250 may also provide support, at least in part, to maintain strain in the dressing 210 .

[0133] In use, the liner 250 may be removed and the dressing 210 may be applied to the surface of the skin of a subject. The support structure 230 may then be removed from the dressing 210, and in response, the stress or strain of the dressing applies a (tangential) compressive force to the skin, thereby treating the skin.

[0134] Dressing 210 may include a release mechanism as further described herein, for example, as described with respect to Figures 3A-3I.

[0135] 3A-3I, the preparation of a prestrained assembly 351 including a prestrained dressing is illustrated. A tensioning device 341 used to prestrain the dressing is shown in use in FIGs. 3A-3D. Various features and steps of preparing the prestrained assembly 351 are further illustrated in FIGs. 3E-3I.

[0136] The pre-strained assembly 351 may comprise the dressing assembly 308 and the strain-maintaining or support structure 330 (see FIG. 3I). The pre-strained assembly 351 may be stored for a period of time prior to use.

[0137] The dressing assembly 308 may include a dressing 310 comprising a relatively planar elastic sheet 360 that defines a plane. The elastic sheet 360 may comprise, for example, a silicone sheet or other elastic material as described herein. The dressing assembly 308 may further comprise an attachment sheet 304, a tensioning sheet 307, a pre-strained assembly release portion 352, and a dressing release portion 319.

[0138] The mounting sheet 304 may be configured to mount the dressing 310 to the support structure 330 using the engaging element 322. The mounting sheet 304 of the dressing assembly 308 may include a first engaging wall or element 322 that extends downwardly relative to the plane of the dressing 310 and includes an inwardly extending hook 323. The engaging element 322 may be attached to the mounting sheet 304 using, for example, an adhesive. The tensioning sheet 307 of the dressing assembly 308 may include a second engaging element 324 that extends downwardly relative to the plane of the dressing 310 and includes an inwardly extending hook 325. The tensioning sheet 307 may be configured to mount the dressing 310 to the support structure 330 using the engaging element 324. The engaging element 324 may be attached to the tensioning sheet 307 using, for example, an adhesive. The tensioning sheet 307 may also be configured to translate tension from the tensioning device 341 to the dressing 310 to impart strain to the dressing 310 .

[0139] The pre-strained assembly release 352 may be configured to release the pre-strained assembly 351 (bandage 310 and support structure 330) from the tensioning device 341 (see, e.g., FIGS. 3E and 3I). The dressing release mechanism 319 may be configured to release the dressing 310 from the engagement elements 322, 324 (including hooks 323, 325) and thus from the support structure 330. The dressing release mechanism 319 may be configured to release the dressing 310 after it has been applied to a subject.

[0140] The dressing 310 of the dressing assembly 308 may have a first edge or side 305 having a length and a second edge or side 306 having a length. The dressing 310 may be joined at the first edge or side 305 to a mounting sheet 304, which may be flexible but relatively less elastic or inelastic than the dressing 310. The mounting sheet 304 may have a first side 382 and a second side 384. When assembled, the mounting sheet 304 may be joined to the elastic sheet 360 of the dressing 310 at a section 375 of the mounting sheet 304 at or near the side 382 of the mounting sheet 304, for example, using a silicone PSA / acrylic PSA combination. The mounting sheet 304 may be joined to the engagement elements 322 and hooks 323 at its side 384, for example, by bonding with an adhesive material, for example, using a silicone PSA / acrylic PSA combination. The attachment sheet 304 may attach the dressing 310 to the support 330 near a first side 305 of the dressing 310 with the engagement elements 322 and hooks 323. The dressing 310 may be attached at its second edge or side 306 to a tensioning sheet 307, which is flexible but may be inelastic or less elastic than the dressing 310. The tensioning sheet 307 may have a first side 372, an intermediate location 373, and a second side 374. When assembled, the tensioning sheet 307 may be joined to the elastic sheet 360 of the dressing 310 at a section 365 of the tensioning sheet 307 at or near the side 372 of the tensioning sheet 307 using, for example, a silicone PSA / acrylic PSA combination. The tensioning sheet 307 may be coupled to the sidewall 324 and hooks 325 at intermediate location 373, for example, by bonding with an adhesive material, for example, using a silicone PSA / acrylic PSA combination. When assembled into the pre-strained assembly 351, the tensioning sheet 307 may couple the dressing 310 to the support structure 330 near the second side 306 of the dressing 310 with the sidewall 324 and hooks 325.The tensioning sheet 307 may be loaded onto the tensioning device 341 at the second side 374, as described in more detail herein. According to some variations, the mounting sheet 304 or the tensioning sheet 307 may be constructed from, for example, low density polyethylene.

[0141] 3A positioned over a support structure 330 to which it can be removably attached as or after the dressing 310 is prestrained to form a prestrained assembly 351. The support 330 may be generally planar and include sides 335, 336 with corresponding edges 335a and 336a that define its length. Other support elements, support structures, and / or strain-maintaining elements may be used, for example, the sides of the dressing 310 or dressing assembly 308 may be clamped and a desired distance maintained between the clamps, for example, using a separation element.

[0142] The dressing 310 of the dressing assembly 308 may be prestrained using, for example, a tensioning device 341 as shown in Figures 3A-3D. The prestrained dressing 310 may then be stored in the prestrained configuration for a period of time prior to use. The tensioning device 341 may be used at the point of manufacture, by an intermediary, or by an end user. The tensioning device 341 may include a planar portion 343 and a circular portion 344 configured to contain a rotating element 345. The rotating element 345 may have a middle section 346 with a slot 347 for receiving and engaging the tensioning sheet 307 of the dressing assembly 308.

[0143] In FIG. 3A, the bandage assembly 308 may be shown on the tensioning device 341 in a first configuration in which it is relatively unstrained. The bandage assembly 308 may be positioned over the support structure 330. This support structure 330 may be positioned over the tensioning device 341 with the top side 333 of the support structure 330 interfacing with the back side 311 of the bandage 310. A first edge 335a of the support structure 330 and a first side or edge 349 of the planar portion 343 of the tensioning device 341 may be engaged and held by the engagement wall 322 and hook 323. A second end 336 and edge 336a of the support 330 may initially be free of engagement with the bandage 310 but in a position to interfacingly contact it. This may allow the bandage 308 to be strained to a desired degree without interference of the support structure 330.

[0144] In use, end 374 of tensioned sheet 307 may be inserted into slot 347 in intermediate section 346 of rotating element 345 of tensioning device 341. Rotating element 345 may then be rotated until tensioned sheet 307 is engaged. Initially, tensioned sheet 307 and bandage 310 may be in an unstrained configuration with minimal deflection when attached to tensioning device 341. As rotating element 345 is rotated, bandage 310 may be strained as tensioned sheet 307 is pulled by rotating element 345 relative to bandage 310 in a tensile strain direction.

[0145] The dressing 310 may be strained by pivoting the rotating element 345 as shown in Figures 3A-3D. Once the tensioning sheet is loaded as the rotating element 345 is pivoted, the tensioning sheet 307 may wrap around the rotating element 345, thereby shortening the distance between the rotating element 345 and the dressing 310 and stretching or straining the dressing 310. A locking mechanism, comprising a ratchet 337 on the rotating element 345 and a pawl 338 on the circular portion 344, may be used to lock the dressing 310 in the strained configuration as shown in Figures 3B-3D. When the tensioning sheet 307 is pulled in the tensile strain direction towards the circular portion 344 of the tensioning device 341, the engagement elements 324 and hooks 325 may also move in the tensile strain direction. The edge 336a of the support includes a ramp 336b that can engage with a ramp 326 on the hook 325 to guide the edge 336a of the support 330 into engagement with the hook 325 as the hook 325 moves toward the circular portion 344 of the tensioning device (see FIGS. 3C-3H). The strain of the pre-strained dressing 310 may be controlled or determined using measuring elements or marks 342 on the rotating element 345, the distance between each of which may correspond to an increment of increased strain or distance. Once the bandage assembly 308 is loaded onto the tensioning device 341, the strain may be determined by the amount the rotating element 345 is rotated. Each mark 342 may correspond to a strain percentage or distance. 0% strain may be identified as the position where the bandage assembly 308 is loaded onto the tensioning device 341 without any deflection and with little to no strain or tension. As shown in Figure 3A, the 0% position may be indicated where mark 342a is aligned with prong 338. As rotational element 345 is rotated, the identified 0% mark 342a may rotate by an amount corresponding to the percent strain. Mark 342b as shown in Figure 3B is aligned with prong 338 when the dressing is strained to a desired amount x as indicated by mark 342b.

[0146] The support structure 330 may maintain the dressing 310 in its strained configuration as shown in FIGS. 3B-3I during storage, and the engagement elements 322, 324 and hooks 323, 325 that engage the support structure 330 prevent the dressing 310 from moving or losing strain. One or more adhesive regions comprising a layer of skin adhesive 340 may be applied to the upper surface 312 of the dressing 310. The adhesive 340 used may be, for example, a suitable pressure activated adhesive (PSA) or a non-pressure sensitive adhesive. The adhesive 340 is shown on the dressing 310 in an unstrained configuration. However, the adhesive may be applied to the dressing 310 after the dressing 310 has been strained. A removable liner 350 may be placed over the adhesive layer 340. The liner 350 may further be selected to maintain the strain in the dressing 310. Such liners may comprise rigid or semi-rigid materials, such as ultra-high molecular weight polyethylene (UHMWPE) with a release coating or layer, a fluoropolymer such as perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), polytetrafluoroethylene (PTFE), or expanded PTFE (ePTFE). Other rigid plastics or resins that may be used include melamine, fiberglass, acrylonitrile butadiene styrene (ABS), or polyvinyl chloride (PVC). In other variations, the rigid liner may be a composite structure, comprising, for example, a flexible liner with a rigid frame or rigid struts, which may comprise metal (e.g., stainless steel) or rigid plastic / resin.

[0147] Once the bandage 310 has been strained and the bandage assembly 308 may be engaged and secured to the support structure 330, the bandage assembly 308 and support structure 330 may be separated from the tensioning device 341 to form a pre-strained assembly 351 which may be used immediately or stored for a period of time.

[0148] The pre-strained assembly release portion 352 may comprise a tear strip 353 attached to the tensioning sheet 307 between an intermediate location 373 and a second side 374 with upper and lower portions 354, 355, respectively (see FIG. 3E ). The tear strip 353 may act to separate the pre-strained assembly 351 from the tensioning device 341 by tearing across the tensioning sheet 307 between the pre-strained assembly 351 and the tensioning device 341.

[0149] In use, after the liner 350 is released, the dressing 310 may be applied to a desired location on the skin of a subject. A user may apply pressure to the backside 333 of the support 330 to activate the adhesive on the dressing 310 and / or to apply compression to the wound. Once applied to the subject, the dressing 310 may be released from the support 330 using the release mechanism 319.

[0150] The release mechanism 319 may include tear strips 309. The tear strips 309 of the release mechanism 319 may each extend to an end 366 of the elastic sheet 360. The tear strips 309 may each be coupled to the bandage assembly 308. The tear strips 309 may be coupled to the mounting sheet 304 of the bandage assembly 308 in a manner that defines a tear path 362 along which the tear strips 309 are drawn to separate the bandage 310 from the support 330. The tear strips 309 may be coupled to the tensioning sheet 307 of the bandage assembly 308 in a manner that defines a tear path 362 along which the tear strips 309 are drawn to separate the bandage 310 from the support 330. Each tear strip 309 may include a top section 347 and a bottom section 348. The bottom section 348 may be unattached or free from the support 330 as shown. The top section 347 of each tear strip 309 may be adjacent to the dressing 310 but unattached thereto. The tensioning sheet 307 and the attachment sheet 304 may be manufactured to be tearable along the length of the material while providing tensile strength in other directions, particularly in the tensioning direction of the material of the tensioning sheet 307 (the direction in which the dressing is tensioned, stressed, or strained). An example of such a material is an LDPE polymer produced by an extrusion process that creates directionally biased grains, whereby the material is tearable in the direction of the grain but has relative resistance to tearing in the direction transverse to the grain. Incisions may be made in the tensioning sheet 307 and the attachment sheet 304 that facilitate tearing along the path 362. The tensioning sheet 307 and the attachment sheet 304 may additionally or alternatively comprise a material such as low density polyethylene (LDPE) with perforations formed along tear lines 362 .

[0151] The dressing 310 may be released from the support 330 by pulling the tear strip 309 to draw the tear strip across the path 362 of the tensioning sheet 307 and the attachment sheet 304. Sections 365 and 375 of the tensioning sheet 307 and the attachment sheet 304, respectively, may remain on the backside 311 of the elastic sheet 360. Sections 385, 395 of the attachment sheet 304 and the tear sheet 307, respectively, that are joined to the tear strip 309 may thereby be separated from the tensioning sheet 307 and the attachment sheet 304. Sections 365 and 375 of the tensioning sheet 307 and the attachment sheet 304, respectively, that are attached to the dressing 310 may thereby be separated from the remaining portions of the tensioning sheet 307 and the attachment sheet 304 that are attached at their ends 305 and 306 to the support structure 330. Thus, the dressing 310 may be released from the remainder of the support structure 330 .

[0152] The dressing 310 may have an unattached portion or edge 315 on its sides 305, 306, respectively, where the elastic sheet 360 is free from the tensioning sheet 307 and the attachment sheet 304. Thus, the dressing 310 may not be strained at the unattached portion 315. The unattached section 315 of the elastic bandage 310 may be unstrained and may be free from the adhesive of the adhesive layer 340 (or may have a reduced amount of adhesive thereon). Thus, lower stresses may develop at the unattached side or edge defined by section 315.

[0153] In use, the adhesive liner 350 may be removed and the dressing 310 may be applied to the surface of a subject's skin. The tear strips 309 on each side of the dressing at the tear line may be retracted to separate the dressing 310 from the support structure 330, mounting sheet 304, and tensioning sheet 307 after the dressing has been applied to the surface of the subject's skin. When the support structure 330, mounting sheet 304, and tensioning sheet 307 are removed from the dressing 310, the stress or strain in the dressing 310 may apply a (tangential) compressive force to the skin, thereby treating the skin.

[0154] 4, multiple strained dressings 410 may be strained in a manner similar to dressing 110, and then each may be rolled as shown in FIG. 4 and attached to a first surface 460 of a single support 430 that is stored in a rolled configuration for dispensing. The strained dressings 410 may be bonded to the first surface 460 of the single support 430 by an adhesive, such as, for example, a high tack / low peel PSA, that maintains the dressing 410 in the strained configuration. Liners 450 may be placed on a second, opposing side 470 of the support 430, positioned such that they are over the skin adhesive on the dressing 410 when the support 430 is rolled. The adhesive liner 450 may also help minimize creep properties of the strained dressing 410. The support 430 may be rolled for storing the dressing 410. When the support 430 is unrolled, the adhesive liner 450 located on the second side 470 and facing the dressing 410 may be released from the dressing 410. The dressings 410 may be separated by perforations 480 so that they may be used individually.

[0155] Referring to FIG. 5, the dressing 510 is shown on a support structure 530 in a strained configuration. The support structure 530 may be constructed of relatively less flexible or relatively more rigid members 532 or sections flexibly bonded together with a relatively more flexible material 533. The support structure 530 may be configured to bend, flex or conform, at least in part, to the contours of the body to which the dressing 510 is to be attached. The dressing 510 may be manufactured or used in a manner similar to the dressings 110, 210, 310 and 410 herein. Although the present invention has been specifically shown and described with reference to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the present invention. With respect to all of the above described embodiments, the steps of the method need not be performed sequentially.

[0156] 10A-10B, a pre-strained bandage assembly 1000 is shown comprising a pre-strained bandage 1010, a support structure 1030, an attachment structure 1020, a release structure 1025, and a removable adhesive liner 1050.

[0157] The dressing assembly 1000 is configured to deliver or apply the dressing 1010 to the skin in a strained configuration where the dressing remains on the skin for a treatment period. The dressing 1010 has a skin adhesive layer 1015 on the top surface of the dressing 1010. Prior to use, a removable adhesive liner 1050 is positioned over the skin adhesive layer 1015 for protection of the adhesive layer 1015. According to some example embodiments, the dressing 1010 may be constructed from elastomers and elastic nonwovens, such as silicone, polyurethane, TPU, TPE, or similar materials. According to some example embodiments, the dressing 1010 may have a durometer hardness in the range of about 40-80. According to some example embodiments, the dressing has a thickness of 0.1-7 mm. According to some example embodiments, the skin adhesive may include a medical grade skin adhesive, such as silicone, PSA, acrylic, or other adhesive. A removable adhesive liner 1050 protects the skin adhesive 1015 and is removable from the skin adhesive 1015 and dressing 1010 prior to application of the dressing.

[0158] The support structure 1030 can be used as an applicator to apply the dressing 1010 to the skin of a subject. The support structure 1030 is configured to maintain strain in the pre-strained dressing for a minimum period of time prior to use. The period may be, for example, less than 2 months, 3 months, 4 months, 6 months, 8 months, 1 year, or up to 1 year, 2 years, 3 years, 4 years, 5 years, or more. The strain may be a minimum defined strain level over a period of time or a minimum period of time. In some further variations, the material and / or configuration is selected to achieve a force drop of less than 20%, 25%, 30%, 40%, 50% over the course of, for example, 3 months, 4 months, 6 months, 8 months, or 12 months. The force drop over the time frame may be within a range of, for example, 15-20%, 15-25%, 15-30%, 20-30%. According to some embodiments, the support structure is relatively flexible and compliant in one direction to allow it to conform to the contours of the body region compared to being stiff in the opposite direction to help hold the dressing in a pre-strained state. According to some example embodiments, the support structure is constructed from paperboard with a Taber stiffness in the cross direction (i.e., parallel to the dressing strain direction) of 160-290 or 160-350, for example, for paperboard with a thickness in the range of 0.020 inches to 0.030 inches. According to some example embodiments, the support structure is constructed from paperboard such as WESTROCK 22pt NATRALOCK® RESIST or ULTRA SEAL (WestRock; Atlanta, GA) paperboard or in the range of 0.022 to 0.028 caliper.

[0159] The attachment structure 1020 is configured to releasably couple the support structure 1030 to the dressing 1010. The attachment structure 1020 comprises a relatively flexible inelastic layer 1021, such as, for example, an LDPE film, metallocene LDPE, or other material lacking a proportional load relationship. The attachment structure 1020 may include, for example, an LDPE film with a thickness in the range of 0.002 inches to 0.004 inches, 0.0025 inches to 0.0035 inches, or 0.0028 inches to 0.0032 inches, or 0.06 mm to 0.10 mm, or 0.06 to 0.09 mm, or 0.07 to 0.08 mm. The flexible inelastic material may be constructed from a thermoplastic material, such as LDPE, that allows the layer to be bonded to the support structure using a thermal process. The attachment structure 1020 is configured to retain the dressing strain for a desired period of time under a variety of temperature, shipping, and storage conditions. After the dressing is pre-strained, the strain is maintained when the attachment structure 1020 is attached to the opposing sides 1013, 1014 of the dressing 1010 on opposing sides 1033, 1034 of the support structure 1030, respectively. As shown in FIG. 10B, the attachment structure 1020 is bonded to the dressing 1010 at interface 1041. According to some example embodiments, an LDPE film strip of the inelastic layer of the attachment structure 1020 is bonded to one side or edge region of the elastomeric dressing 1010 using a differential dual coat adhesive of silicone and acrylic. For example, the silicone portion may have material specifications from SA1020 manufactured by Adhesive Applications and the acrylic portion may have material specifications from SA1911 manufactured by Adhesive Applications. The elastomeric dressing may be surface treated, for example, with corona, flame, reactive gas, or plasma to provide a higher surface energy material (approximately 50-60 dynes / cm) for bonding to the custom differential double coat adhesive. The attachment structure 1020 may have a single layer or multi-layer construction.

[0160] As illustrated in FIG. 10B, the mounting structure 1020 is coupled to the support structure 1030 at an interface 1042. According to some embodiment examples, the interface can be formed using thermal bonding. According to some examples, the interface 1042 is created by heat sealing one or more strips of a film or material, such as an LDPE layer of the mounting structure 1020 to the support structure 1030, which is constructed from a paperboard film coated with a hot melt glue or polycoat (e.g., WESTROCK NATRALOCK® RESIST or ULTRA SEAL or UltraSeal). According to one example, a seal temperature of 150 degrees Celsius at a seal pressure of 25-28 PSI was applied for a seal time of 1.5 seconds. In other variations, the heat seal temperature may be in the range of 140 degrees Celsius to 160 degrees Celsius and / or the heat seal time may be in the range of 1.0 seconds to 2.0 seconds.

[0161] A release structure 1025 is configured to release the dressing 1010 from the support structure 1030. According to some example embodiments, the release structure 1025 may include a portion and / or extension of the inelastic layer 1021 of the attachment structure 1020. Preferably, the portion of the inelastic layer 1021 is not directly bonded to the support structure 1030 or otherwise at the bond interface 1042 between the attachment structure 1020 and the support structure 1030. The inelastic layer 1021 may have a grain direction that allows it to separate along a linear direction. This may be further promoted or enhanced when stress propagation features 1026, such as one or more perforations, indentations, or tears in the inelastic layer 1021, are provided or created. The linear direction may be in a machine direction that is approximately perpendicular to the cross direction or the direction of the dressing strain. The grain allows for a difference in tear resistance (Elmendorf tear ASTM D1922) between the machine direction and the cross direction of the material. As shown, the release structure 1025 comprises a stress transfer feature 1026, such as a perforation, a notch, a tear, or other stress transfer feature. In some embodiments, a void 1043 may be provided near the perforation 1026 to further facilitate separation. The release structure 1025 further comprises a release tab 1027 that extends out from the bandage 1010, the removable adhesive lining 1050, and / or the support structure 1030 to facilitate gripping and that is used to decouple the support structure 1030 from the bandage 1010, i.e., the inelastic layer 1021 and the support structure side 1033 adjacent the bandage side 1013, and the support structure side 1014 of the inelastic layer 1021 and the support structure adjacent the bandage side 1014. According to some example embodiments, a fabric stiffener 1028 can be positioned between the dressing 1010 and the attachment structure 1020 adjacent the interface 1041 to assist in decoupling the attachment structure 1020.

[0162] In use, the removable adhesive lining 1050 is removed from the skin adhesive layer 1015 and the pre-strained dressing 1010 is attached to a skin surface using the now exposed skin adhesive 1015. The release tabs 1027 are actuated to sever the attachment structure 1020 along the grain, separating the dressing 1010 from the support structure 1030.

[0163] 11A-11F, processes and sub-processes for manufacturing or assembling a pre-strained dressing are illustrated.

[0164] As shown in FIG. 11A, a device carrier with a precursor dressing assembly is attached to the manufacturing unit, and the carrier is fed through the manufacturing unit 1100. Examples of some embodiments of the device carrier with the precursor dressing assembly are illustrated in FIG. 12A-12B as described herein. Examples of some embodiments of the manufacturing unit and subunit are illustrated in FIG. 13-15H as described herein. In a first step 1101, the manufacturing liner is removed from the precursor dressing assembly. In a second step 1102, a side of the dressing is secured or anchored to a corresponding side of a support structure. In a third step 1103, the dressing is strained using a straining element attached to the dressing, and the dressing is secured to the support structure in the strained configuration. In a fourth step 1104, any remaining unsealed portions of the straining element may be removed from the precursor dressing assembly. In a fifth step 1105, a removable adhesive liner is applied to the skin adhesive on the dressing assembly to form the completed dressing assembly. These steps may be at different locations along the manufacturing unit 1100, or one or more steps may be performed sequentially at the same location along the manufacturing unit 1100.

[0165] Referring to Figure 11B, a process or sub-process for removing the production liner is illustrated. The sides of the precursor dressing assembly are immobilized (1110). For example, the sides may be clamped. The production protective liner may then be manually or otherwise removed (1111). The precursor assembly may then proceed to a second stage.

[0166] Referring to FIG. 11C, a process or sub-process (1102) for affixing or anchoring a side of a support element to a corresponding side of a support structure is illustrated. A precursor dressing assembly, such as illustrated in FIG. 12A-12B, including an attachment structure, such as described with respect to FIG. 10A-10B, is indexed and / or advanced to a second stage of the manufacturing process (1121). The attachment structure is provided on the precursor assembly, which is attached to the dressing. The side of the precursor assembly is immobilized, for example, by being clamped, or otherwise immobilized (1122). A heat sealing element applies heat to the attachment structure and the adjacent support structure, forming a heat-sealed thermal bond at the interface, thereby bonding the dressing to the support structure with the attachment structure (1123). The precursor dressing assembly may then move to a third stage.

[0167] Referring to FIG. 11D, a process or sub-process for straining a bandage and attaching the bandage in a strained configuration to a support structure is illustrated. A precursor bandage assembly is provided, and a first side of the support structure is bonded to a first side of the bandage using an attachment structure, and an opposing side with the bandage is attached to an attachment element that is not attached to a substrate (1131). The first side of the support structure is immobilized, e.g., clamped or otherwise immobilized (1132). The attachment structure on the opposing side is a free flap or loose side that forms a straining sheet that can extend past the side of the support structure until the bandage is strained. The straining sheet or attachment structure of the loose side is attached or clamped to a straining unit (1133). The straining unit then uses the attachment structure to lift the bandage away from the support structure (1134). The straining unit then strains the bandage using the attachment structure (1135). The bandage and attachment structure are then placed onto a support structure (1136). The attachment structure between the strained bandage and a heat seal location (see second heat seal 1263 in FIG. 16C) is clamped (1137). A heat sealing element applies heat to the attachment structure and adjacent support structure to form a heat sealed thermal bond at the interface between the support structure and the attachment structure, thereby bonding the bandage in the strained configuration to the support structure (1138). The precursor bandage assembly may then be unclamped and moved to a fourth stage.

[0168] Referring to FIG. 11E, a process or sub-process for removal of the straining element is illustrated. A precursor bandage assembly is provided with the strained bandage attached to a support structure, but with a flap or remaining width of the straining sheet or attachment structure that is used to apply strain to the bandage (1141). The attachment structure is heated or melted using a heating element (1142). A knife or other cutting element strikes and cuts the attachment structure flap (1143). An air jet may be used to remove debris or waste (1144). The precursor bandage assembly may then move to a fifth stage.

[0169] 11F, a process or sub-process for applying a liner to a dressing is illustrated. A dressing assembly with a pre-strained dressing is provided (1151). A liner is indexed into position over the skin adhesive layer of the dressing (1152). The liner is placed on the dressing over the adhesive layer (1153) and laminated onto the dressing using an actuator with a compliant surface, e.g., foam, rubber, etc. (1154).

[0170] Although the processes and sub-processes described herein refer to various manufacturing stages, the precursor assembly may be physically moved to a different stage or manufacturing unit, or may otherwise remain in place while steps in a subsequent stage or stages are performed. Any sub-process or combination of sub-processes described herein may be used in a method or pre-strained dressing manufacturing process.

[0171] 12A and 12B illustrate a device carrier 1205 with a precursor dressing assembly 1200 removably positioned on the carrier. The carrier 1205 may be a thin substrate such as POLYMASK SURFACE GUARD® low tack film (Tekra; New Berlin, WI). The carrier 1205 and precursor dressing assembly 1200 may be formed into a roll for easy dispensing and mounting onto a manufacturing or assembly unit, such as illustrated in FIG. 13 described herein. The precursor dressing assembly 1200 is attached to the carrier 1205 with a low tack adhesive. The carrier 1205 may be passed through one or more stages of a manufacturing unit or may be attached at the end of one or more stages of a manufacturing unit. The carrier 1205 moves the precursor dressing assembly 1200 through one or more stages of a manufacturing unit.

[0172] The precursor bandage assembly 1200 as shown may have portions of a final bandage assembly preassembled and then bonded to a carrier 1205. As shown as an example of some embodiments, the precursor bandage assembly 1200 includes a support structure 1230 similar to the support structure 1030 described in Figures 10A-10B. Attachment structures 1220a and 1220b are attached to the dressing 1210 at an interface (not shown), such as interface 1041, with an adhesive as described with reference to Figures 10A-10B herein. Attachment structures 1220a and 1220b are positioned on the support structure 1230 with attachment structure 1220a temporarily attached to the support structure 1230 while attachment structure 1220b is not initially attached to the support structure 1230. Attachment structures 1220a and 1220b are formed from a non-elastic flexible material with particles for thermal bonding capabilities and preferential release in a selected direction. Examples of such materials are described with reference to Figures 10A-10B. The attachment structure has a flap 1229 or strain-imparting sheet that extends across the width of the support structure 1230 on the side 1231. The release structure 1225 includes a pull tab 1227, and the stress transfer features 1026 may be formed from the same sheet of material as the attachment structures 1220a or 1220b. A temporary manufacturing liner 1260 may be placed over the skin adhesive layer on the dressing 1210.

[0173] 13, a manufacturing unit 1300 is shown having a first subunit or station 1301, a second subunit or station 1302, a third subunit or station 1303, a fourth subunit or station 1304, and a fifth subunit or station 1305. A roller 1310 is configured to carry a roll of precursor dressing assembly 1210 to be loaded onto the device carrier 1205 (FIGS. 12A-12B). The roller 1310 is further configured to feed the device carrier 1205 and precursor dressing assembly 1210 through one or more subunits or stages of the manufacturing unit 1300. A spacer 1306 is located between the subunits or stations to control the position of the dressing assembly 1210 in the subunits 1301-1305.

[0174] A first subunit 1301, which may be a liner stripping module, includes opposing clamps 1311 that clamp sides of the precursor dressing assembly to allow removal of a production liner placed over the skin adhesive of the dressing. As shown in Figure 16A, the precursor dressing assembly 1200 has a production liner 1260 over the dressing 1230 as it enters the first subunit. As the precursor dressing assembly leaves the first subunit, the production liner 1260 is removed from the precursor dressing assembly 1200.

[0175] 13, the second subunit 1302, which may be the first seal module, is configured to affix or anchor a side of the support element 1230 to a corresponding side of the attachment structure 1220a. The subunit 1302 includes a heat seal element 1322 arranged to apply heat to the attachment structure and adjacent support structure to form a heat-sealed thermal bond at the interface between the support structure 1230 and the attachment structure 1220a. An index element 1306 positions the precursor dressing assembly 1200 in the longitudinal and transverse directions such that the heat seal 1262 is precisely located at the interface 1042 (between the support element 1230 and the attachment structure 1220a), for example, as illustrated in FIG. 10B. As shown in FIG. 16B, the precursor dressing assembly 1200 does not have a heat seal when it enters the second subunit 1302. When the precursor bandage assembly 1200 leaves the second subunit 1302 , a heat seal 1262 is formed on the precursor bandage assembly 1200 .

[0176] The third subunit 1303, which may be a straining and sealing module, comprises a first clamp 1331 actuated by an actuator 1331a. The first clamp is arranged to clamp and hold a first side of the support element 1230 when straining the dressing and heat sealing the opposite side of the dressing assembly. When the precursor dressing assembly is moved into the third subunit 1303, the first clamp 1331 is actuated by its actuator 1331a. The third subunit 1303 further comprises a straining unit 1332 including a second clamp 1333 and a third clamp 1334 and their corresponding actuators 1333a, 1334a configured to hold the loose flap 1229 during the straining and heat sealing process, as described in more detail with reference to FIG. 11D. The straining unit 1332 is further illustrated in FIGS. 14 and 15A-15H. The third subunit 1303 further includes a heat sealing element 1338 arranged to apply heat to the mounting structure and the adjacent support structure to form a heat-sealed thermal bond at the interface between the support structure and the mounting structure, thereby bonding the dressing to the support structure in the strained configuration.

[0177] 16C, the precursor bandage assembly 1200 is unstrained and clamped on only one side as it enters the third subunit 1303. Once within the subunit 1303, the attachment structure 1220b is clamped along the mid-length section 1265a and the lateral long section 1265b and a heating element is applied therebetween to form a second heat seal 1263. This second heat seal 1263 is formed on the precursor bandage assembly 1200 to attach the strained bandage 1210s to the support element 1230. The width of the lateral long section 1265b is typically greater than the mid-length section 1265a, and the second heat seal 1263 may be relatively closer to (or otherwise abut) the mid-length section 1265a and relatively farther from the lateral long section 1265b. The clamps are then removed from areas 1265 a and 1265 b after the second heat seal 1263 and the dressing assembly 1200 can then exit the third subunit 1303 .

[0178] Figures 15A-15H depict the straining and sealing mechanism of the third subunit 1303, which performs the function depicted in Figure 16C. In Figure 15A, the precursor dressing assembly 1200 with unstrained dressing 1210 enters the subunit 1303. The straining unit 1332 with clamp 1331 is actuated by actuator 1331a against the edges of the attachment structure 1220a and support structure 1230 previously heat sealed in the second subunit. In Figure 15B, the free flap 1229 of the opposing attachment structure 1220b is then engaged by upper / second and lower / third clamps 1333, 1334 by actuating actuator 1333a of upper clamp 1333 against lower clamp 1334. In Figure 15C, the actuator 1334a of the lower clamp 1334 is actuated to lift the bandage 1210 via the clamped mounting structure 1220b up and away from its support structure 1230. In Figure 15D, the entire straining unit 1332 is then displaced laterally using the actuator 1336a of the lateral displacement assembly 1336, thereby straining the bandage 1210s through its mounting structure 1220b as the opposing mounting structure 1220a remains clamped. Next, in Figure 15E, the actuator 1334a of the lower clamp 1334 is actuated to lower the strained bandage 1210s back down onto the support structure 1220. In Figure 15F, the fourth clamp 1337 is lowered by its actuator 1337a to further facilitate clamping of the attachment structure 1220b such that the strained dressing 1210s is maintained in a strained configuration on the support structure 1230. In Figure 15G, the actuator 1338a of the heat sealing element 1338 is lowered by its actuator 1338a, thereby heat sealing the attachment structure 1220b to the support structure 1230 and forming the second heat seal 1263. Then, in Figure 15H, the actuator 1338a of the heat sealing element 1338 is retracted along with the actuator 1337a of the fourth clamp 1337.The actuators 1331 a, 1333 a of the first and upper / second clamps 1331, 1333 are also retracted to unclamp the mounting structures 1220 a, 1220 b and the support structure 1230, and the actuator 1336 a of the lateral displacement assembly 1336 is returned to a non-straining position or configuration. The dressing assembly 1200 is then ready for the fourth sub-unit.

[0179] The fourth subunit 1304, which may be configured as a removal or cutting module, comprises a clamp 1341 arranged to clamp the previously created heat seal 1262. The fourth subunit 1304 further comprises a heating element 1342 arranged to heat or melt the flap 1229 to facilitate cutting or severing. The fourth subunit 1304 further comprises a knife or other cutting element 1443 (e.g., a PEEK knife blade) arranged to strike and / or cut the flap 1229. The fourth subunit 1304 further comprises an air jet 1344 arranged to remove debris or waste.

[0180] 16D, the precursor bandage assembly 1200 has a remaining flap 1229 when it enters the fourth subunit 1304. When the precursor bandage assembly 1200 leaves the fourth subunit 1304, the flap 1229 is removed from the precursor bandage assembly 1200.

[0181] 13, the fifth subunit 1305, which may be a liner applicator module, includes an indexer 1351 configured to index a liner 1050 on a carrier roll or carrier strip into position over the skin adhesive layer of the dressing 1210. A laminator 1352 laminates or otherwise applies the liner 1050 onto the adhesive side of the strained dressing 1210s via a liner carrier (not shown).

[0182] As shown in FIG. 16E, the precursor dressing assembly 1200 does not have a liner 1050 when it enters the fifth subunit 1305. When the precursor dressing assembly 1200 leaves the fifth subunit 1305, it is a completed dressing assembly with a liner 1050. This application may be performed by rollers, clamps, or presses. After application of the liner 1050, the rollers, clamps, or presses are lifted up and pulled away or separated from the strained dressing 1210s or liner 1050. The liner carrier may be separated or separated from the liner 1050 at this point or later along the manufacturing process. Similarly, the device carrier 1205 may be separated or separated from the support structure 1030 simultaneously with, before, or after removal of the liner carrier.

[0183] While the subject matter herein has been particularly shown and described with reference to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention. With respect to all of the above-described embodiments, the steps of the method need not be performed sequentially.

Claims

1. A strained treatment device, comprising: a strained elastic bandage material; an adhesive layer disposed on a surface of the elastic bandage; a support structure comprising a polycoated paperboard with a Taber stiffness of at least 160; two or more attachment structures positioned between the strained elastic bandage and the support structure, the attachment structures including flexible inelastic strips; Equipped with The attachment structure is adhered to the dressing by a high shear adhesive and thermally bonded to the polycoat of the paperboard, the area of ​​thermal bond having a width within the range of 0.10 inches to 0.25 inches.

2. 10. The strained therapeutic device of claim 1, wherein a length of the area of ​​the thermal bond is equal to or exceeds a length of the adhesive bond between the attachment structure and the dressing.

3. 1. A method of making a strained therapeutic device, comprising: Attaching a device carrier to a precursor dressing assembly; removing a production liner from the precursor dressing assembly; heat fusing a first region of the dressing to a first region of a support structure; straining the dressing and heat fusing a second region of the dressing in a strained configuration to a second region of the support structure; Applying an adhesive liner and A method comprising:

4. The method of claim 3 , wherein the dressing further comprises first and second attachment structures.

5. Attaching a distortion element to the dressing; pulling the straining element away from a first region of the bandage to strain the bandage; The method of claim 3 further comprising:

6. Lifting the strain imparting element before retracting the strain imparting element; After the distortion imparting element is pulled, the distortion imparting element is lowered. The method of claim 5 further comprising:

7. The method of claim 5 , wherein attaching the distortion element to the dressing occurs after thermal melting of the first region.

8. The method of claim 4 , wherein the heat that melts the first and second regions of the dressing is located on the first and second attachment structures.

9. The method of claim 8 , wherein the first and second mounting structures each comprise two lengths of boreholes spaced apart from each other.

10. 10. The method of claim 9, wherein the thermal fusing of the first and second regions is performed on each of the attachment structures to the sides of the two lengths of perforation.

11. 1. A manufacturing assembly comprising: a transport assembly for moving the plurality of components along a path of movement; a first clamping assembly configured to reversibly clamp together first sides of a subset of the plurality of components; a first thermal fusion assembly adjacent a first side of the subset of the plurality of components and configured to thermally fuse the subset of the plurality of components together; 1. A straining assembly comprising: a second clamping assembly configured to reversibly clamp together second sides of a subset of the plurality of components; a first separation assembly configured to reversibly displace the second clamp assembly; a second assembly configured to reversibly displace the strain application assembly away from the first clamp assembly; and a distortion assembly comprising: a second thermal fusion assembly adjacent a second side of the subset of the plurality of components and configured to thermally fuse the subset of the plurality of components together; A manufacturing assembly comprising:

12. The assembly of claim 11 , wherein the first clamp assembly and the second clamp assembly are configured to clamp in a first direction.

13. The assembly of claim 12 , wherein the first separation assembly is configured to lift the second clamp assembly in a second direction opposite the first direction.

14. The assembly of claim 12 , wherein the second isolation assembly is configured to displace the straining assembly in a third direction orthogonal to the first direction.

15. 12. The assembly of claim 11, further comprising a third clamp assembly configured to reversibly clamp a subset of the plurality of components together, the third clamp assembly being located between the first clamp assembly and the second clamp assembly.

16. The assembly of claim 15 , wherein the third clamp assembly is located between the first clamp assembly and the second thermal melt assembly.

17. The assembly of claim 11 , further comprising a cutting assembly configured to cut a subset of the plurality of components.

18. The assembly of claim 17 , wherein the cutting assembly is configured to cut the subset of the plurality of components adjacent a second side of the subset of the plurality of components.

19. 1. A straining assembly comprising: a first clamping assembly configured to reversibly clamp together a second side of a subset of the plurality of components; a first separation assembly configured to reversibly displace a second clamp assembly; a second assembly configured to reversibly displace the strain application assembly away from the first clamp assembly; and a first thermal fusion assembly adjacent a second side of the subset of the plurality of components and configured to thermally fuse the subset of the plurality of components together; A distortion assembly comprising:

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