BRPI0709297A2 - reduced pressure delivery system for applying a reduced pressure tissue treatment to a tissue site and method for promoting tissue growth in a tissue site - Google Patents

Abstract

REDUCED PRESSURE APPLICATION SYSTEM FOR THE APPLICATION OF A TISSUE TREATMENT WITH REDUCED PRESSURE TO A TISSUE SITE AND METHOD TO PROMOTE TISSUE GROWTH IN A TISSUE SITE. It is a low pressure application system that includes a main distributor, a blockage prevention member, and first and second ducts in fluid communication with the primary distributor. The primary dispenser includes a flexible wall that surrounds a primary flow passage and is adapted to be placed in the vicinity of a tissue site. The blocking prevention member is positioned within the primary flow passage. A plurality of openings are arranged in the flexible wall to communicate with the primary flow passage. The first conduit is fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage and the plurality of openings. The second conduit includes an outlet near the primary flow passage or an exit from the first conduit to purge the primary flow passage or the first conduit to prevent blockages.

Description

REDUCED PRESSURE APPLICATION SYSTEM FOR APPLICATION OF REDUCED PRESSURE TISSUE TREATMENT TO A TISSUE SITE AND METHOD TO PROMOTE TISSUE GROWTH ON A TISSUE SITE

BACKGROUND OF THE INVENTION

FIELD OF INVENTION

The present invention relates generally to a system or method of promoting tissue growth, and more specifically to a system for applying reduced pressure tissue treatment to a tissue site.

DESCRIPTION OF THE CORRELATE TECHNIQUE

Reduced pressure therapy is increasingly employed to promote wound healing in tissue wounds that are slow to heal or do not heal without reduced compression therapy. Typically, reduced pressure is applied to the wound site through an open cell foam that serves as a distributor for distributing the reduced pressure. The open cell foam is sized to fit the existing wound, to be in contact with the wound, and then periodically replaced by smaller foam pieces as the wound begins to heal and shrink. Frequent replacement of open cell foam is necessary to minimize the amount of tissue that the foam cells grow. The significant internal growth provided can cause pain to patients during foam removal.

Reduced pressure therapy is typically applied to open wounds that do not heal. In some cases, the tissues that have been cured are subcutaneous, and in other cases the tissues are located inside or over the dermal tissue. Traditionally, reduced pressure therapy has been applied primarily to soft tissues. Reduced pressure therapy has not typically been employed for the treatment of closed deep tissue wounds because of the difficulty of access presented to wound portals. In addition, reduced pressure therapy has not been employed in connection with healing of bone defects or promoting bone growth, mainly due to access problems. Surgical exposure of a patient to apply reduced pressure therapy can create more problems than solutions. Finally, devices and systems for applying reduced pressure therapy have advanced just beyond the open cell foam pieces that are manually formed to fit into a wound site then removed after a period of reduced pressure therapy.

BRIEF DESCRIPTION OF THE INVENTION

The problems presented by existing wound healing systems and methods are solved by the systems and methods of the present invention. A reduced pressure application system is provided according to an embodiment of the present invention for applying reduced pressure to a tissue site. The reduced depression delivery system includes a primary dispenser having a flexible wall surrounding a primary flow passage and adapted to be placed close to the tissue site.

The flexible wall includes an inner surface having a plurality of projections extending from at least a part of the inner surface and for the primary flow passage. The flexible wall further includes a plurality of openings through the flexible wall which communicate with the primary flow passage. A first conduit is fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage and the plurality of openings. A second conduit includes at least one outlet in the vicinity of the primary flow passage or at least one first conduit outlet to remove blockages or at least one outlet of or near the first conduit.

According to another embodiment of the present invention, there is provided a reduced pressure delivery system including a primary manifold having a flexible wall surrounding a primary flow passage and adapted to be placed near a provided site. The flexible wall includes a plurality of openings through the flexible wall that communicate with the primary flow passage. A cellular material is positioned within the primary flow passage, and the cellular material includes a plurality of flow channels. A first conduit is fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage, cellular material, and plurality of openings.

A second conduit includes at least one outlet in the vicinity of the primary flow passage or at least one first conduit outlet for removing blockages at or near one outlet of the first conduit.

In accordance with yet another embodiment of the present invention there is provided a reduced depression application system which includes a primary dispenser having a flexible wall surrounding a primary flow passageway and adapted to be placed near a tissue site. The primary distributor includes a locking prevention member positioned within the primary flow passage. A plurality of apertures are arranged in the flexible wall to communicate with the primary flow passage.

A secondary distributor is positioned adjacent to the primary distributor and is adapted to contact the tissue site such that the secondary distributor communicates fluidly with the primary distributor but is adapted to prevent contact between the primary distributor and the tissue site. A first conduit is fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage and the plurality of openings.

In another embodiment of the present invention, a method for promoting tissue growth in a tissue includes surgical positioning of a primary dispenser in close proximity to the tissue site. The primary distributor includes a flexible wall surrounding a primary flow passage. The flexible wall includes a plurality of openings through the flexible wall communicating with primary flow passage. The primary dispenser additionally included a blockage prevention member positioned within the primary flow passage. The method additionally included the surgical positioning of a secondary distributor in contact with the tissue site such that the secondary distributor fluidly communicates with the primary distributor but prevents contact between the primary distributor and the tissue site. Reduced pressure is applied to the tissue site through the primary flow passage, the plurality of openings, and the secondary distributor.

Other objects, features, and advantages of the present invention will become apparent with reference to the following drawings and detailed description.

BRIEF DESCRIPTION OF DRAWINGS

FIGURE 1 illustrates a perspective view of a reduced pressure application apparatus according to one embodiment of the present invention, wherein the reduced pressure application apparatus having a plurality of projections extending from a flexible barrier to create a plurality of flow channels. FIGURE 2 illustrates a front view of the reduced pressure application apparatus of FIGURE 1;

FIGURE 3 illustrates a top view of the reduced pressure application apparatus of FIGURE 1;

FIGURE 4A illustrates a side view of the reduced pressure application apparatus of FIGURE 1, wherein the reduced pressure application apparatus has a single lumen reduced pressure application tube;

FIGURE 4B illustrates a side view of an alternative embodiment of the reduced pressure application apparatus of FIGURE 1, wherein the reduced depression application apparatus has a double lumen pressure application tube;

FIGURE 5 illustrates a perspective enlarged view of the reduced pressure delivery apparatus of FIGURE 1;

FIGURE 6 illustrates a perspective view of a reduced pressure delivery apparatus according to one embodiment of the present invention, wherein the reduced pressure application apparatus has a cellular material attached to a flexible barrier having a spine portion and a portion of wing, and cellular material having a plurality of flow channels;

FIGURE 7 illustrates an anterior view of the reduced pressure application apparatus of FIGURE 6;

FIGURE 8 shows a cross-sectional side view of the reduced pressure delivery apparatus of FIGURE 7 taken at XVII-XVII;

FIGURE 8A illustrates a cross-sectional front view of a low pressure application apparatus in accordance with an embodiment of the present invention;

Figure 8B illustrates a side view of the reduced pressure applying apparatus of Figure 8A, Figure 9 illustrates a front view of a reduced pressure applying apparatus in accordance with an embodiment of the present invention that is being used to apply a reduced pressure tissue treatment. to a patient's bone;

FIGURE 10 illustrates a histological section of an Iho skull showing the undamaged simple bone;

FIGURE 11 illustrates a histological section of a rabbit skull showing induction of granulation tissue after application of reduced pressure tissue treatment;

FIGURE 12 illustrates a histological section of a rabbit skull showing the deposition of new bone following the application of reduced pressure tissue treatment;

FIGURE 13 illustrates a histological section of a rabbit skull showing the deposition of new bone following the application of reduced pressure tissue treatment;

FIGURE 14 illustrates a photograph of a cranium skull that has two critically sized defects formed in the necranium;

FIGURE 15 illustrates a photograph of the cranium skull of FIGURE 14 showing a calcium phosphate support structure introduced within one of the critical size defects and a stainless steel screen overlapping according to the critical size defects;

FIGURE 16 illustrates a photograph of the cranium skull of FIGURE 14 showing the application of reduced pressure arrested treatment to critical size defects;

FIGURE 17 illustrates a histological section of a rabbit skull following reduced pressure tissue treatment, where the histological section shows the deposition of new bone within the decal phosphate support structure, FIGURE 18 illustrates a radiograph of the critical size defect containing the support structure of FIGURE 15 after six days of reduced pressure tissue treatment and two weeks after surgery;

FIGURE 19 illustrates a radiograph of the critical size defect containing the support structure of FIGURE 15 after six days of reduced pressure tissue treatment and twelve weeks after surgery;

FIGURE 20 illustrates a front view of a reduced pressure delivery system according to an embodiment of the present invention, wherein the reduced pressure delivery system has a dispensing delivery tube that is employed to percutaneously insert a reduced pressure delivery device into a gifted site;

FIGURE 21 illustrates an enlarged front view of the dispensing application tube of FIGURE 20, wherein the dispensing application tube contains a reduced pressure application apparatus having a flexible barrier and / or cellular material in a compressed position;

FIGURE 22 illustrates an enlarged front view of the dispensing application tube of FIGURE 21, wherein the flexible cap and / or cellular material of the reduced pressure application apparatus are shown in an expanded position after being pushed from the dispensing application tube;

FIGURE 23 illustrates a front view of a reduced pressure delivery system according to one embodiment of the present invention, wherein the reduced pressure delivery system has a dispensing delivery tube that is employed to percutaneously insert a reduced pressure delivery device to a provided site, and the reduced pressure delivery apparatus is shown outside the dispensing application tube but confined by an impermeable membrane in a compressed position;

FIGURE 24 illustrates an anterior view of the reduced pressure application system of FIGURE 23, wherein the reduced pressure application apparatus is shown outside the dispensing application tube but confined by an impermeable membrane in a relaxed position;

FIGURE 25 illustrates an anterior view of the reduced pressure application system of FIGURE 23, wherein the reduced pressure application apparatus is shown outside the dispensing application tube but confined by an impermeable membrane in an expanded position;

FIGURE 25A illustrates an anterior view of the reduced pressure application system of FIGURE 23, wherein the reduced pressure application apparatus is shown outside the dispensing application tube but surrounded by an impermeable membrane in an expanded position;

FIGURE 26 illustrates a front view of a reduced pressure delivery system according to one embodiment of the present invention, wherein the reduced pressure delivery system has a dispensing delivery tube that is employed to percutaneously insert a reduced pressure delivery device to a provided, and the reduced pressure delivery apparatus is shown outside the dispensing delivery tube but confined by an impermeable membrane having a take-off seal;

FIGURE 26A illustrates a front view of a reduced pressure delivery system according to one embodiment of the present invention;

FIGURE 27 illustrates a front view of a reduced pressure delivery system according to one embodiment of the present invention, wherein the reduced pressure delivery system has a dispensing delivery tube that is employed to percutaneously inject a reduced pressure delivery device into a gifted site;

FIGURE 27A illustrates a front view of a reduced pressure delivery system according to one embodiment of the present invention, wherein the reduced pressure delivery system has a dispensing delivery tube that is employed to percutaneously apply a reduced pressure delivery device to a waterproof membrane positioned at a tissue site;

FIGURE 28 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention;

FIGURE 29 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention;

FIGURE 30 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention;

FIGURE 31 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention;

FIGURE 32 illustrates a cross-sectional front view of a reduced pressure delivery apparatus according to an embodiment of the present invention, wherein the reduced pressure delivery apparatus includes a basin prosthesis having a plurality of flow channels to apply a reduced pressure to an area of bone surrounding the hip prosthesis;

FIGURE 33 illustrates a cross-sectional front view of the hip prosthesis of FIG. 32 having a second plurality of flow channels for applying fluid to the area of bone surrounding the hip prosthesis;

FIGURE 34 illustrates a flowchart of a method for securing a patient's joint using reduced pressure tissue treatment according to one embodiment of the present invention;

FIGURE 35 illustrates a cross-sectional front view of a reduced pressure delivery apparatus according to an embodiment of the present invention, wherein the reduced pressure delivery apparatus includes an orthopedic fixation device that has a plurality of flow channels for applying reduced pressure. an area of bone adjacent to the orthopedic fixation device;

FIGURE 36 illustrates a cross-sectional front view of the orthopedic fixation device of FIGURE 35 having a second plurality of flow channels for applying a fluid to the bone area adjacent to the orthopedic fixation device;

FIGURE 37 illustrates a flowchart of a method for healing a bone defect in a bone using reduced pressure tissue treatment according to one embodiment of the present invention;

FIGURE 38 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention; and

FIGURE 39 illustrates a flowchart of a method of administering a reduced pressure tissue treatment to a tissue site according to one embodiment of the present invention.

FIGURES 40-48 illustrate various views of a reduced pressure delivery system according to one embodiment of the present invention, wherein the reduced pressure application system has a main distributor which includes a flexible wall surrounding a main flow passage and a plurality of openings. in the flexible wall;

FIGURES 49-50 illustrate perspective and top cross-sectional views of a reduced depression application system according to one embodiment of the present invention, wherein the reduced pressure application system has a main manifold that is integrally connected to a pressure application tube reduced;

FIGURE 51 illustrates a perspective view of the main distributors of FIGURES 40-50 being applied with a secondary distributor to a bone tissue site;

FIGURE 52 illustrates a schematic view of a reduced pressure delivery system having a valve fluidly connected to a second pipe according to one embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form part thereof, and in which the specific preferred embodiments in which the invention may be practiced are shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it should be understood that other embodiments may be used and that equitable logical, mechanical, electrical structural changes may be made without departing from the scope or scope of the invention. To avoid details not necessary to allow elements skilled in the art to practice the invention, the description may omit certain information about the knowledge of elements skilled in the art. The following detailed description should therefore not be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims.

As used herein, the term "elastomeric" means that it has the properties of an elastomer. The term "elastomer" refers generally to a polymeric material having rubber-like properties. More specifically, most elastomers have elongation rates of more than 100% and a significant proportion of resilience. The resilience of a material refers to the material's ability to recover from elastic deformation. Examples of elastomers may include, but are not limited to, natural rubbers, polyisoprene, butadiene and styrene rubber, chloroprene rubber, polybutadiene, nitrile rubber, butyl rubber, ethylene and propylene rubber, ethylene and propylene diene monomer , chlorosulfonated polyethylene, polysulfide rubber, polyurethane, and silicones.

As used herein, the term "flexible" refers to an object or material that can be bent or flexed. Elastomeric materials are typically flexible, but reference here to flexible materials does not necessarily limit the selection of materials to elastomers only. The use of the term "flexible" with respect to a material or a low pressure delivery apparatus of the present invention generally refers to the material's ability to conform or match closely to the shape of a tissue site. For example, the flexible nature of a reduced pressure delivery device employed in treating a bone defect may allow the apparatus to be wrapped or folded around the defective portion of the bone.

The term "fluid" as used herein generally refers to a gas or liquid, but may also include any other flowable material including, but not limited to, gels, colloids and foams.

The term "impermeable" as used herein refers generally to the ability of a membrane, cover, foil, or other blocking substance to slow transmission of both liquids and gases. Impermeability may be employed to refer to coatings, sheets, or other membranes that are resistant to liquid transmission while allowing gases to be transmitted through the membrane. While a permeable membrane may be impermeable to liquids, the membrane can simply reduce the transmission rate of all or only certain liquids. The use of the term "impermeable" should not mean that it implies that an impermeable membrane is above or below any industry standard measure for impermeability, such as a particular value of water vapor transfer rate (WVTR).

The term "dispenser" as used herein generally refers to a substance or structure that is employed to assist in the application of reduced pressure, application of liquids, or removal of liquids from a tissue site. A dispenser typically includes a plurality of flow channels or passages which are interconnected to improve the distribution of the liquid supplied and removed from the tissue area around the dispenser. Exemplary dispensers may include without limitation devices that have structural elements arranged to form flow channels, cellular foam such as open cell foam, porous tissue collections, and liquids, gels and foams that include or cure to include flow channels.

The term "reduced pressure" as used herein generally refers to a pressure lower than ambient pressure at a tissue site that is subject to treatment. In most cases, this reduced pressure will be less than the atmospheric pressure at which the patient is located. Alternatively, the reduced pressure may be less than a hydrostatic pressure provided at the tissue site. Although the terms "vacuum" and "negative pressure" may be employed to describe pressure applied to the tissue site, the actual pressure applied to the tissue site may be significantly lower than the pressure normally associated with a full vacuum. Reduced pressure may initially generate fluid flow in the tissue and in the area of the tissue site. As the hydrostatic pressure around the tissue site approaches the desired reduced pressure, the flow may subside and the reduced pressure is then maintained. Unless otherwise indicated, the pressure values given herein are standard pressures.

The term "support structure" as used herein refers to a substance or structure employed to enhance or promote cell growth and / or tissue formation. A support structure is typically a three-dimensional porous structure that provides a template for cell growth. The support structure may be infused, coated, or may comprise cells, growth factors, or other nutrients to promote cell growth. A support structure may be employed as a dispenser according to the embodiments described in the present invention for administering the reduced pressure arrested treatment to a tissue site.

The term "tissue site" as used herein refers to a wound or defect located within or on any tissue, including but not limited to bone tissue, adipose tissue, thin tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. The term "tissue site" may also refer to areas of any tissue that are not necessarily wounded or defective, but are preferably areas in which it is desired to add or promote additional tissue growth. For example, treatment of tissue with reduced pressure may be employed in certain areas of the tissue for growth of additional tissue that may be harvested and transplanted to another tissue site.

Referring to FIGURES 1-5, a reduced pressure application apparatus or wing distributor 211 in accordance with the principles of the present invention includes a flexible barrier 213 having a spine portion 215 and a pair of wing portions 219. Each portion of Wing 219 is positioned along opposite sides of the spine portion 215. The spine portion 215 forms an arcuate channel 223 which may or may not extend the entire length of the wing distributor 211.

Although the spine portion 215 may be centrally located in the wing distributor 211 such that the width of the wing portions 219 is equal, the spine portion 215 may also be displaced as illustrated in FIGURES 1-5, resulting in one of the wing portions 219 being wider than the other wing part 219. The extra width of one of the wing parts 219 can be particularly useful if the wing distributor 211 is being employed for bone regeneration or healing and the wider wing distributor 211 should be wrapped around the fastening hardware attached to the bone.

The flexible barrier 213 is preferably formed of an elastomeric material such as a desilicone polymer. An example of a suitable silicone polymer includes MED-6015 manufactured by Nusil Technologies of Carpinteria, California. It should be noted, however, that the flexible barrier 213 could be made of any other flexible biocompatible material. The flexible barrier 213 has a flexible protective coating 227 which adds strength and durability to the flexible barrier 213. The thickness of the flexible barrier 213 enclosing the flexible protective coating 227 may be smaller on the arcuate channel 223 than that on the wing parts 219. If a silicone polymer is employed To form flexible barrier 213, a silicone adhesive may also be employed to assist in bonding with flexible protective coating 227. An example of a silicone adhesive could include MED-1011, also sold by Nusil Technologies. Flexible backing 227 is preferably made of a polyester braided fabric such as Bard 6013 manufactured by C.R. Bard of Tempe, Arizona. However, the flexible backing 227 could be made of any flexible biocompatible material capable of adding strength and durability to the flexible barrier 213. Under certain circumstances, if the flexible barrier 213 was made of a suitably resistant material, the flexible protective coating 227 could be omitted.

It is preferable that the flexible barrier 213 or flexible protective liner 227 is impervious to liquids, air, and other gases, or alternatively the flexible protective coating 227 and flexible barrier 213 may be impervious to liquids, air, and other gases. Flexible barrier 213 and flexible protective liner 227e may also be constructed of bioabsorbable materials which do not have to be removed from a patient's body after use of the reduced pressure application apparatus 211. Suitable bioresorbable materials may include, without limitation, a polymeric acid mixture. polylactic acid (PLA) and polyglycolic acid (PGA). Polymeric mixture may also include, without limitation, polycarbonates, polyfumarates and capralactones. Flexible housing 213 and flexible backing 227 may also serve as a support structure for new cell growth, or a supportive material material may be employed in conjunction with flexible barrier 213 and flexible backing 227 to promote cell growth. Suitable support structure material may include, without limitation, calcium phosphate, collagen, PLA / PGA, coral apatite hydroxy, carbonates, or processed allograft materials. Preferably, the support structure material will have a high fraction of voids (i.e. is a high content).

In one embodiment, the flexible backing 227 may be adhesively bonded to a flexible barrier surface 213. If a silicone polymer is employed to form the flexible barrier 213, a desilicone adhesive may also be employed to join the flexible protective coating 227 to the flexible barrier. 213. Although a bracket is the preferred method of attachment when flexible protective liner 227 is attached to the flexible barrier surface 213, any suitable attachment may be attached.

The flexible barrier 213 includes a plurality of projections 231 extending from the wing portions 219 on a flexible barrier surface 213. The projections 231 may be cylindrical, spherical, hemispherical, or cubic in shape, provided that at least some portion of each projection is projected. 231 is in a different plane than the plane associated with the flexible backing side 213 to which projections 231 are joined. In this regard, a particular projection 231 is not required even to have the same shape or size as other projections 231; For example, projections 231 may include a random mix of different shapes and sizes. Accordingly, the distance by which each projection 231 extends from the flexible barrier 211 could vary, but may also be uniform between projection plurality 231.

Placement of projections 231 on flexible barrier 213 creates a plurality of flow channels 233 between projections. When projections 231 are of uniform size and shape and are evenly spaced at flexible barrier 213, flow channels 233 created between projections 231 are similarly uniform. Variations in the size, shape, and spacing of projections 231 may be employed to alter the size and flow characteristics of flow channels 233.

A reduced pressure delivery tube 241 is positioned within the arcuate channel 223 and joined to the flexible barrier 213 as illustrated in FIGURE 5. The reduced pressure application tube 241 may be attached solely to the flexible barrier 213 or flexible protective liner 227, or the tube 241 could be joined to both flexible barrier 213 and flexible backing 227. The reduced pressure application tubing 241 includes a distal orifice 243 at a distal end of the tube 241. The tubing 241 may be positioned such that the distal orifice 243 is located at some point. point along arcuate channel 223, but tube 241 is preferably positioned so that distal orifice 243 is located approximately halfway along the longitudinal length of arcuate channel 223. Distal orifice 243 is preferably of an elliptical or oval shape to engage the tube. 241 along a plan that is oriented less than ninety (90 ) degrees to the longitudinal axis of the pipe241. Although orifice 243 may also be round, the elliptical shape of orifice 243 enhances fluid communication with flow channels 233 formed between projections 231.

The reduced pressure delivery tube 241 is preferably made of paraline or urethane coated silicone. However, any liner tubing material may be employed to construct the 241 reduced pressure application tube. Other coatings that may coat the tube include heparin, anti-coagulants, anti-fibrinogens, anti-adherents, anti-thrombinogens, hydrophilic coatings. .

In one embodiment, the reduced pressure delivery tube 241 may also include exhaust ports, or exhaust ports 251 positioned along the reduced pressure application tube 241 as an alternative to distal port 243 and beyond distal port 243, for increased communication. between the reduced pressure delivery tube 241 and the flow channels 233. The reduced pressure application tube 241 may be positioned only over a portion of the arcuate longitudinal length 223 as shown in FIGURES 1-5, or, alternatively, it may be positioned along the entire longitudinal length of the arcuate channel 223. If it is positioned such that the reduced pressure delivery tube 241 occupies the entire length of the arcuate channel 223, the distal orifice 243 may be capped such that the fluid communication between tube 241 and flow channels 233 occurs through the openings of and xaustão 251.

The reduced pressure delivery tube 241 additionally included a proximal port 255 at one proximal end of the tube 241. The proximal port 255 is configured to couple with a reduced pressure source, which is described in more detail below with reference to FIGURE.

9. the reduced pressure delivery tube 241 illustrated in FIGURES 1-3, 4A and 5 includes only a single lumen, or passage 259. It is possible, however, that the reduced pressure application tube 241 includes multiple lumens, such as a pressure tube. double lumen 261 illustrated in FIGURE 4B. Double lumen tube 261 includes a first lumen 263 and a second lumen 265. Use of a double lumen tube provides separate passages of fluid communication between the proximal end of the reduced pressure delivery tube 241 and the flow channels 233. For example, use The double lumen tube 261 may be employed to permit communication between the reduced depression source and the flow channels 233 along the first lumen 263. The second lumen 265 may be employed to introduce a fluid into the flow channels 233. The fluid may be filtered by the air or other gases, antibacterial agents, antiviral agents, cell growth promoting agents, irrigation fluids, chemically active fluids, or any other fluids. If multiple fluids are to be introduced into the flow channels 233 through separate fluid communication passages, a reduced pressure delivery tube may be provided with more finger lumens.

Referring still to FIGURE 4B, a horizontal divider 271 separates the first and second lumens 263, 265 from the reduced pressure delivery tube 261, resulting in the first lumen 263 being positioned above the second lumen 265. The relative position of the first and second lumens 263, 265 may vary depending upon the manner in which fluid communication is provided between the lumens 263, 265 and the flow channels 233. For example, when the first lumen 263 is positioned as shown in FIGURE 4B, Similar exhaust openings for exhausting openings 251 may be employed to permit communication with the flow channels 233. When the second lumen 263 is positioned as illustrated in FIGURE 4B, the second lumen 263 may communicate with flow channels 233 through a hole distalimilar to the distal orifice 243. Alternatively, the multiple lumens of a reduced pressure delivery tube could be positioned side by side with a vertical divider separating the lumens, or the lumens could be arranged concentric or coaxially.

It should be apparent to one of ordinary skill in the art that the provision of independent fluid communication passages could be accomplished in a number of different ways, including that of providing a multiple lumen tube as described above. Alternatively, independent fluid communication passages may be provided by joining a single-lumen tube to another single-lumen tube, or by using separate single-lumen or multiple lumen tubes.

If separate tubes are employed to obtain separate fluid communication passages to flow channels 233, the spine portion 215 may include multiple arched channels 223, one for each tube. Alternatively, the channel channel 223 may be enlarged to accommodate multiple tubes.

An example of a reduced pressure delivery apparatus having a separate reduced pressure delivery pipe from a fluid delivery pipe is discussed in more detail below with reference to FIGURE 9. With reference to FIGURES 6-8, a reduced pressure application apparatus or wing distributor 311 according to the principles of the present invention includes a flexible barrier 313 having a spine part 315 and a pair of wing parts 319. Each wing part 319 is positioned along opposite sides of the spine part 315. The spine part 315 forms an arcuate channel 323 which may or may not extend the entire length of the wing distributor 311.

Although the spine part 315 may be centrally located in the wing distributor 311 such that the size of the wing parts 319 is equal, the spine part 315 may also be displaced as illustrated in FIGURES 6-8, resulting in one of the wing parts 319 being wider than the other wing part 319. The extra width of one wing part 319 may be particularly useful if the wing distributor 311 is being used in connection with bone regeneration or healing and the wider wing distributor 311 is to be wrapped around the fastening hardware attached to the bone.

A cellular material 327 is attached to flexible barrier 313 and may be provided as a single piece of material covering the entire surface of flexible barrier 313 extending through the spine portion 315 and both wing portions 319. Cellular material 327 includes a deflection surface (not visible in FIGURE 6) which is disposed adjacent to the flexible barrier 313, a main distribution surface 329 opposite the fixing surface, and a plurality of perimeter surfaces 330.

In one embodiment, flexible barrier 313 may be similar to flexible barrier 213 and include a flexible protective coating. Although an adhesive is a preferred method of attaching cellular material 327 to flexible barrier 313, flexible barrier 313 and cellular material 327 could be joined by any other appropriate method of attachment or left to the user to mount at the treatment site. Flexible cap 313 and / or flexible backing serve as an impermeable barrier to the transmission of fluids such as liquids, air and other gases.

In one embodiment, a flexible barrier and a flexible protective coating may not be provided separately to support cellular material 327. Instead, cellular material 327 may have an integral barrier layer which is an impermeable portion of cellular material327. The barrier layer could be formed of a closed cell material to prevent fluid transmission, thereby replacing the flexible barrier 313. If an integral barrier layer is employed with the cellular material 327, the barrier layer may include a spine portion and portions. wing as described above with reference to flexible barrier 313.

The flexible barrier 313 is preferably made of an elastomeric material such as a silicone polymer. An example of a suitable silicone polymer includes MED-6015 manufactured by Nusil Tecnhologies of Carpinteria, California. It should be noted, however, that the flexible barrier 313 could be made of any other flexible biocompatible material. If the flexible barrier encloses or then incorporates a flexible backing, the flexible backing is preferably made of braided polyester fabric such as Bard 6.013 manufactured by C.R. Bard of Tempe, Arizona. However, flexible protective liner 227 could be made of any flexible bi-compatible material that has the ability to add strength and durability to flexible barrier 313.

In one embodiment, cellular material 327 is an open cell cross-linked polyetherurethane foam with pore sizes ranging from approximately 400 to 600 microns. An example of this foam may include GranuFoam manufactured by Kinetic Concepts, Inc. of San Antonio, Texas. Cellular material 327 may also be gauze, felt mats, or any other biocompatible material that provides fluid communication through a plurality of channels in three dimensions.

Cellular material 327 is primarily an "open cell" material that includes a plurality of cells fluidly connected to adjacent cells. A plurality of flow channels is formed by and between the "open cells" of cellular material 327. Flow channels allow fluid communication throughout this portion of cellular material 327 that has open cells. Flow cells and channels may be uniform in shape and size, or may include standard or random variations in format and size. Variations in shape and size of cells of cellular material 327 result in variations in flow channels, and such characteristics may be employed to alter fluid flow characteristics through cellular material 327. Cellular material 327 may also include portions that include "closed cells" . These closed cell parts of cellular material 327 contain a plurality of cells, most of which are not fluidly connected to adjacent cells. An example of a closed cell part is described above as a barrier layer that can be replaced in place of the flexible barrier 313. Similarly, closed cell parts could be selectively arranged in the cell material 327 to prevent fluid transmission through perimeter surfaces 330 of the cell material 327. .

Flexible barrier 313 and cellular material 327 may also be constructed of bioabsorbable materials which do not have to be removed from a patient's body after use of the reduced pressure application apparatus 311. Suitable bioresorbable materials may include, without limitation, a polylactic acid polymer mixture (PLA) and polyglycolic acid (PGA). Polymeric mixture may also include, without limitation, polycarbonates, polyfumarates and capralactones. Flexible barrier 313 and cellular material 327 may also serve as a support structure for growth of new cells, or a supportive structure material may be employed in conjunction with flexible barrier 313, flexible protective coating 327 and / or cellular material327 to promote growth. cell growth. Suitable materials of the support structure may include, without limitation, calcium phosphate, collagen, PLA / PGA, coral hydroxyapatites, carbonates, or processed allograft materials. Preferably, the support structure material will have a high fraction of voids (i.e., a high air content).

A reduced pressure delivery tube 341 is positioned within the arcuate channel 323 and joined to the flexible barrier 313. The reduced pressure application tube 341 may also be attached to the cellular material 327, or if only a cellular material 327 is present, the application tube 341 may be attached only to cellular material 327. The reduced pressure delivery tube341 includes a distal port 343 at a distal end tube 341 similar to the distal port 243 of FIGURE 5. The reduced pressure application tube 341 may be positioned positively. such that the distal hole 343 is located anywhere along the arcuate channel 323, but is preferably located approximately midway along the longitudinal length of the arched channel 323. The distal hole 343 is preferably formed of an elliptical or oval shape when cutting the tube 341. along a plane that is oriented less than ninety (90) degrees in relation to the longitudinal axis of the tube 341. Although the orifice may also be round, the elliptical shape of the orifice increases fluid communication with the cellular material flow channels 327.

In one embodiment, the reduced pressure delivery tube 341 may also include exhaust ports, or exhaust ports (not shown) similar to the exhaust ports 251 of FIGURE 5. Exhaust ports are positioned along the tube 341 as an alternative to the distal orifice. 343 as well as the distal port 343 to increase fluid communication between the reduced pressure delivery tube 341 and the flow channels. As previously described, the reduced pressure delivery tube 341 may be positioned along only a portion of the longitudinal length of the arcuate channel 323, or alternatively may be positioned along the entire longitudinal length of the arcuate channel 323. If so positioned Since the reduced pressure delivery tube 341 occupies the entire arcuate channel 323, the orifice 343 may be capped such that any fluid communication between the tube 341 and the flow channels occurs through the exhaust openings.

Preferably, the cellular material 327 overlaps and comes in direct contact with the reduced pressure delivery tube 341. The cellular material 327 may be connected to the reduced pressure application tube 341, or the cellular material 327 may simply be attached to the flexible barrier313. If the reduced pressure delivery tube 341 is positioned such that it extends only to an average point of the arcuate channel 323, the cellular material 327 may also be connected to the spine portion 315 of the flexible barrier 313 in that area of the arcuate channel 323 which does not contain the tube. application pressure reduced 341.

The reduced pressure delivery tube 341 additionally included a proximal port 355 at one proximal end of the tube 341. The proximal port 355 is configured to couple with a reduced pressure source, which is described in more detail below with reference to FIGURE 9. The reduced pressure delivery tube 341 illustrated in FIGURES 6-8 includes only a single lumen, or passage 359. However, the reduced pressure application tube 341 may include multiple lumens, such as those previously described with reference to FIGURE 4B. Use of a multiple lumen tube provides separate fluid communication passages between the proximal end of the reduced pressure application tube 341 and the flow channels as described above. These separate fluid communication passages may also be provided by tubosparates having a single lumen or multiple lumens which communicate with the flow channels.

Referring to FIGURES 8A and 8B, a reduced pressure application apparatus 371 in accordance with the principles of the present invention includes a reduced pressure application tube 373 having an extension portion 375 at a distal end 377 of the reduced pressure application tube 373. The extension portion 375 is preferably arcuate deformed to match the curvature of the reduced pressure application tube 373. The extension portion 375 may be formed by removing a portion of the reduced depression delivery tube 373 at the distal end 377, thereby forming a notch 381. which has a shoulder 383. A plurality of projections 385 is disposed on an internal surface 387 of the reduced pressure delivery tube 373 to form a plurality of flow channels 391 between projections 385. Projections 385 may be similar in size, shape and spacing. such as the projections described with reference to FIGURES 1-5. The 371 low pressure delivery apparatus is particularly suited for the application of reduced pressure and regeneration to the connective tissues that may be received in the notch 381. Ligaments, tendons, and cartilage are non-limiting examples of tissues that may be treated by the tissue. application of reduced pressure 371.

Referring to FIGURE 9, a reduced pressure applying apparatus 411 similar to the other reduced pressure applying apparatus described in the present invention is employed in applying a reduced compression tissue treatment to a tissue site 413, such as a human bone 415 of a patient. . When employed to promote bone tissue growth, treatment of reduced compression tissue may increase the healing rate associated with a fracture, a nonunion, an empty space, or other bone defects. It is further believed that low pressure arrested treatment may be employed to improve osteomyelitis recovery. Therapy may also be employed to increase localized bone densities in osteoporotic patients. Finally, reduced pressure tissue treatment can be employed to accelerate and improve osseointegration of orthopedic implants such as hip implants, knee implants, and fixation devices.

Referring still further to FIGURE 9, the reduced pressure delivery apparatus 411 includes a reduced pressure delivery tube 419 having a proximal end 421 fluidly connected to a reduced pressure source 427. The reduced pressure source 427 is a pump or other device having the ability to apply reduced pressure to the tissue site 413 through the reduced pressure application tube 419 and a plurality of flow channels associated with the reduced pressure application apparatus 411. applying reduced pressure to the provided site 413 is effected by placing the wing portions of the reduced pressure applying device 411 adjacent to the provided site 413, which in this particular example involves wrapping the wing parts around an empty space defect 429 in bone 415 The reduced depression application apparatus 411 may be inserted surgically or percutaneously. When percutaneously inserted, the reduced pressure delivery tube 419 is preferably inserted through a sterile insertion sheath that penetrates the patient's skin.

Application of reduced pressure tissue treatment typically generates granulation tissue in the area surrounding the tissue site 413. Granulation tissue is a common tissue that is often formed prior to body repair. Under normal circumstances, degranulation tissue may be formed in response to a foreign body or during wound healing. Granulation tissue is typically used as a support structure for healthy replacement tissue and also results in the development of some scar tissue. Granulation tissue is highly vascularized, and the higher growth and growth rate of highly vascularized tissue in the presence of reduced pressure promotes the growth of new tissue at the endowed site 413.

Referring still further to FIGURE 9, a fluid delivery tube 431 may be fluidly connected at a distal end to the flow channels of the reduced pressure application 411. The fluid delivery tube 431 includes a proximal end 432 which is fluidly connected. 433. If the fluid being applied to the provided site is air, the air is preferably filtered through a filter 434 capable of filtering particles smaller than 0.22 pm in order to clean and sterilize. oar. The introduction of air into the tissue site 413, especially when the tissue site 413 is located below the skin surface, is important in order to facilitate a tapering of the tissue site 413, thereby reducing or preventing obstruction of the reduced pressure delivery tube 419. 0 fluid delivery tube 431 and fluid application source 433 may also be employed to introduce other fluids to the tissue site 413, including, without limitation, an antibacterial agent, an anti-viral agent, a cell growth promoting agent, an irrigation fluid, or other chemical agents. When percutaneously inserted, fluid delivery tube 431 is preferably inserted through a sterile insertion sheath that penetrates the patient's skin tissue.

A pressure sensor 435 may be operatively connected to the fluid delivery tube 431 to indicate if the fluid delivery tube 431 is clogged with blood or other body fluids. Pressure sensor 435 may be operatively connected to fluid delivery source 433 to provide feedback so that the amount of fluid introduced into the tissue site 413 is controlled. A check valve (not shown) will also be operably connected near the distal end of the fluid delivery tube 431 to prevent blood or other body fluids from entering the fluid delivery tube 431. Independent fluid communication passages provided by the reduced pressure delivery tube 419 and the fluid delivery tube 431 may be effected in a number of different ways, including that provided for a single lumen-multiple lumen tube as previously described with reference to FIGURE 4B. One of ordinary skill in the art will recognize that sensors, valves, and other components associated with fluid application tube 431 could also similarly be associated with a particular lumen in the reduced depression application tube 419 if a multi-lumen tube is to be attached. It is preferable that any lumen or tube that fluidly communicates with the tissue site is coated with an anticoagulant to prevent accumulation of body fluid or blood within the lumen or tube. Other coatings that may coat the lumens or tubes include, without limitation, heparin, anti-coagulants, anti-fibrinogens, anti-adherents, anti-thrombinogens, and hydrophilic coatings.

Referring to FIGURES 10-19, the tests revealed the positive effects of reduced compression tissue treatment when applied to bone tissue. In a particular test, treatment of reduced pressure tissue was applied to the skull of several rabbits to determine its effect on bone growth and regeneration. The specific objectives of the tests were to find out the effect of treating low pressure tissue in rabbits that have no skull defect or injury, the effect of treating reduced pressure tissue in rabbits that have critical skull defects, and the effect of using a support structure material with reduced pressure tissue treatment to treat critical size defects in the skull. The specific test protocol and number of rabbits are listed below in the

Table 1

<table> table see original document page 33 </column> </row> <table>

Table 1: Test Protocol

Critical-size defects are defects in a tissue (eg, the skull) whose size is large enough that the defect will not only heal for life. For rabbits, drilling a full-thickness hole through the skull that is approximately 15 mm in diameter creates a critical docranium size defect.

Referring more specifically to FIGURE 10, a histological section of a rabbit skull showing undamaged simple bone is illustrated. The skull bone tissue is magenta in color, the surrounding soft tissue is white, and the periosteum layer is highlighted by yellow asterisks. In FIGURE 11, the rabbit skull is illustrated after application of the reduced pressure tissue treatment six days followed by immediate tissue harvest. The bone and periosteum are visible, and a layer of degranulation tissue has been developed. In FIGURE 12, the rabbit skull is illustrated after application of the reduced compression tissue treatment for six days and followed by immediate tissue harvesting. The histological section of FIGURE 12 is characterized by the development of new bone tissue underlying the granulation tissue. The bone tissue is highlighted by yellow asterisks. In FIGURE 13, the cranium skull is illustrated after application of the reduced pressure arrested treatment for six days followed by immediate tissue harvesting. New bone and periosteum are visible. This histological appearance of bone development in response to reduced pressure tissue treatment is very similar to the histological appearance of bone development in a very young animal that is undergoing very rapid growth and deposition of new bone.

Referring more specifically to FIGURES 14-19, various photographs and histological sections are illustrated, which show the procedures and results of reduced pressure tissue treatment on a skull with critically sized defects. In FIGURE 14, a rabbit skull is illustrated in which two critical size defects were created. Critical size defects of total thickness are approximately 15 mm in diameter. In FIGURE 15, a stainless steel screen was placed over one of the critical size defects, and a calcium phosphate support structure was placed within the second critical size defect. In FIGURE 16, a reduced pressure tissue treatment apparatus similar to those described in the present invention is employed to apply reduced pressure to critical size defects. The amount of pressure applied to each defect was 125 mm Hg of standard pressure. Reduced pressure was applied according to one of the protocols listed in Table 1. In FIGURE 17, a histological section of the skull is illustrated after six days of reduced pressure tissue harvesting and harvesting twelve weeks after surgery. The illustrated section includes the calcium phosphate support structure, which is indicated by arrows.

Application of reduced pressure tissue treatment resulted in significant growth of new bone tissue, which is highlighted in FIGURE 17 by asterisks. The rate of bone growth is significantly higher than in critically sized defects that contain identical calcium phosphate support structures but have not been treated as reduced pressure tissue treatment. This observation suggests that there may be a threshold level or duration of therapy required to elicit a prolific response from our new. The effects of treatment with reduced pressure tissue are most pronounced in specimens collected twelve weeks after surgery, indicating that treatment with reduced pressure initiates a cascade of biological events leading to intensified formation of new bone tissue.

Critical size defects covered with stainless steel mesh (FIGURE 15) but without defect support material serve as controls among animals with minimal new bone growth. These data highlight the advantage of an appropriate support structure material and the positive effect of reduced pressure tissue treatment on support structure integration and biological performance. FIGURES 18 and 19 illustrate radiographs of critical size defects containing support structure six days after tissue treatment with reduced pressure. FIGURE 18 illustrates the defect two weeks after surgery and indicates some ossonovo deposition within the support structure. The main structure of the supporting structure is still evident. FIGURE 19 illustrates the effect twelve weeks after surgery and shows the almost complete cure of the critical size defect and a loss of the complete architecture of the main support structure due to tissue integration, i.e. formation of new bone within the support structure matrix.

Referring to FIGURE 20, a reduced pressure delivery system 711 according to an embodiment of the present invention applies reduced pressure tissue treatment to a tissue site 713 of a patient. The reduced pressure delivery system 711 includes a dispensing delivery tube 721. The dispensing application tube 721 may be a catheter or cannula and may include features such as a directional unit 725 and a guide wire 727 that enable the dispensing application tube. 721 is guided to the site provided 713. The placement and direction of the guide wire 727 and the dispensing tubing 721 may be performed using endoscopy, ultrasound, fluoroscopy, auscultation, palpation, or any other appropriate delocalization technique. Dispensing delivery tube 721 is employed to percutaneously insert a reduced pressure application apparatus to the patient tissue site 713. When percutaneously inserted, the delivery tube 721 is preferably inserted through a sterile insertion sheath that penetrates the patient's skin.In FIGURE 20, tissue site 713 includes the bone tissue adjacent to a fracture 731 in a patient bone 733 . Dispensing delivery tube 721 is inserted through the patient's skin 735 and any soft tissue 739 surrounding the bone 733. As discussed earlier, tissue site 713 may also include any other type of tissue, including, without limitation, adipose tissue, muscle tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments.

Referring to FIGURES 21 and 22, the reduced pressure application system 711 is further illustrated. Dispense tube 721 may include a tapered distal end 743 to facilitate insertion through the patient's skin 735 and soft tissue 739. The tapered distal end 743 may also be configured to radially flex outwardly to an open position such that the inner diameter of the distal end 743 is substantially equal to or greater than the inner diameter in other parts of the tube 721. The open position of the distal end 743 is schematically illustrated. in FIGURE 21 by discontinuous lines 737.

Dispensing delivery tube 721 additionally included a passage 751 in which a reduced pressure application apparatus 761 or any other reduced pressure application apparatus is contained. The reduced pressure application apparatus 761 includes a flexible barrier 765 and / or cellular material 767 similar to that described with reference to FIGURES 6-8. The flexible barrier 765 and / or cellular material 767 is preferably coiled, folded, or otherwise compressed around a reduced pressure application tube 769 to reduce the cross-sectional area of the reduced pressure application apparatus 761 within passage 751.

The reduced pressure delivery apparatus 761 may be placed within the passage 751 and guided to the fabric site 713 after placement of the distal end743 of the dispensing delivery tube 721 at the provided site 713. Alternatively, the reduced depression application apparatus 761 may be previously positioned within passage 751 before dispensing delivery tube 721 is inserted into the patient. If the reduced pressure application apparatus 761 is to be pushed through passage 751, a biocompatible lubricant may be employed to reduce the friction between the reduced pressure application apparatus 761 and the distributing application tube 721. When the distal end 743 has been positioned in place of the fabric 713 and the reduced pressure applying apparatus 761 have been applied to the distal end 743, the reduced pressure applying apparatus 761 is then pushed to the distal end 743, causing the distal end 743 to expand outwardly in the open position. The reduced pressure application apparatus 761 is pushed out of the dispensing application tube 721, preferably into an empty space or vacuum adjacent to the tissue site 713.

Void space or vacuum is typically formed by soft tissue dissection, which may be effected by means of the skin. In some cases, the tissue site 713 may be located at a wound site, and a void space may be naturally present due to the anatomy of the wound.

In other examples, void space may be created by balloon dissection, acute section dissection, blunt dissection, hydrodissection, pneumatic dissection, ultrasonic dissection, electrocautery dissection, laser dissection, or any other appropriate technique. dissection When the reduced pressure application apparatus 761 enters the void adjacent the fabric site 713, the flexible barrier 765e and / or cellular material 767 of the reduced pressure application apparatus 761 unwinds, unfolds, or decompresses (see FIGURE 22) such that reduced depression application apparatus 761 may be brought into contact with fabric site 713. Although not required, flexible barrier 765 and / or cellular material 767 may be subjected to a vacuum or reduced pressure applied through reduced pressure application tube 769. to compress flexible barrier 765 and / or cellular material 767. The unfolding of flexible barrier 765 and / or cellular material 767 can be effected either by relaxing the reduced pressure applied through the reduced pressure application tube 769 or by applying positive pressure through the pressure tube. reduced pressure application 769 to aid in the unwinding process. The placement and final handling of the 761 reduced pressure delivery apparatus may be performed using endoscopy, ultrasound, fluoroscopy, auscultation, palpation, or any other appropriate localization technique. After placement of the reduced pressure delivery device761, the dispensing delivery tube 721 is preferably removed from the patient, but the reduced pressure delivery tube associated with the reduced depression delivery device 761 remains in place to allow percutaneous application of the reduced pressure to the delivery. tissue site713.

Referring to FIGURES 23-25, a reduced pressure application system 811 according to one embodiment of the present invention includes a dispensing delivery tube 821 having a tapered distal end843 that is configured to radially flex to an open position such that the inner diameter of the distal end 843 is substantially equal to or larger than the inner diameter in other parts of tube 821.

The open position of the distal end 843 is shown schematically in FIGURES 23-25 by the discontinuous lines 837.

Dispensing delivery tube 821 additionally includes a passageway containing a reduced pressure application apparatus 861 similar to the other reduced pressure application apparatus described in the present invention. The reduced pressure delivery apparatus 861 includes a flexible barrier 865 and / or cellular material 867 which is preferably wrapped, folded, or otherwise compressed around a reduced depression delivery tube 869 to reduce the cross-sectional area of the pressure application apparatus. reduced 861 within the pass.

A waterproof membrane 871 having an inner space 873 is disposed around the low pressure application apparatus 861 such that the reduced pressure application apparatus 861 is contained within the inner space 873 of the waterproof membrane 871. The waterproof membrane 871 may be a balloon, a sheath, or any other type of membrane that may prevent transmission of fluidity such that the impermeable membrane 871 can assume at least one of a compressed position (see FIGURE 23), a relaxed position (see FIGURE 24), and an expanded position (see Figures 25 and 25A). The waterproof membrane871 may be sealedly connected to the dispensing application tube 821 such that the internal space 873 of the waterproof membrane 871 is in fluid communication with the passage of the dispensing application tube 821. The waterproof membrane 871 may be alternatively attached to the watering tube. reduced pressure application 869 such that the internal space 873 of the waterproof membrane 871 is in fluid communication with the passage of the reduced pressure application tube 869. The waterproof membrane 871 may preferably be attached to a control tube or separate control lumen (see, for example). FIGURE 25A) which communicates fluidly as internal space 873.

In one embodiment, the impermeable membrane 871 may be employed to further reduce the cross-sectional area of the reduced pressure application apparatus 861 within the passageway. To accomplish this, a pressure is applied to the internal space 873 of the impermeable membrane 871, which is less than the ambient pressure surrounding the impermeable membrane 871. A significant part of the air or other fluid within the internal space 873 is thereby evacuated by placing the membrane 871 in the compressed position shown in FIGURE 23. In the compressed position, the impermeable membrane 871 is pulled in such a way that a compressive force is applied to the reduced pressure delivery apparatus 861 to further reduce the cross-sectional area of the reduced pressure delivery apparatus 861 As described above with reference to FIGURES 21 and 22, the reduced pressure delivery apparatus 861 may be applied to the tissue site after displacement of the distal end 843 of the delivery tube 821 at the tissue site. Placement and manipulation of the waterproof membrane 871 and the reduced pressure application apparatus 861 may be performed using endoscopy, ultrasound, fluoroscopy, auscultation, palpation, or any other appropriate delocalization technique. The waterproof membrane 871 may include radiopaque markers 881 which enhance the visualization of waterproof membrane 871 under fluoroscopy prior to its removal.

After the reduced pressure delivery apparatus 861 is pushed through the distal end 843, the reduced pressure applied to the inner space 873 may be relaxed to place the impermeable membrane 871 in the relaxed position (thereby FIGURE 24), thereby facilitating easier removal of the pressure apparatus. reduced pressure application 861 of the waterproof membrane 871. A removal instrument 885, such as a switch, stylus, or other sharp instrument, may be employed to break the permeable membrane 871. Preferably, the removal instrument885 is inserted through the reduced pressure application tube. 869 and may be advanced in contact with the impermeable membrane 871. After the rupture of the impermeable membrane871, the removal instrument 885 and the impermeable membrane871 may be withdrawn through the dispensing tube 821, allowing the flexible barrier 865 and / or cellular material 867 of the application apparatus reduced pressure 861 unwinds, unfolds, or decompresses in a manner that the reduced pressure delivery apparatus 861 may have placed in contact with the tissue site. The unfolding act of the flexible barrier 865 and / or cellular material 867 may occur automatically after pressure reduction reduced to the internal space 873 and removal of the permeable membrane 871. In some cases, positive pressure may be applied through the reduced pressure delivery tube869 to help unwinding or decompressing flexible barrier 865 and / or cellular material 867. After final placement of the reduced pressure delivery device 8 61, the dispensing delivery tube 821 is preferably removed from the patient, but the reduced pressure delivery tube 869 associated with the device. Reduced pressure delivery apparatus 861 remains in place to allow the reduced pressure to be delivered to the tissue site percutaneously.

The impermeable membrane 871 may also be nailed for dissecting tissue adjacent to the provided site prior to placing the reduced pressure applying apparatus 861 against the tissue site. After the reduced pressure application apparatus 861 and the intact permeable membrane 871 are pushed through the distal end 843 of the dispensing application tube 821, air or another fluid may be injected or pumped into the inner space 873 of the impermeable membrane 871. A liquid is preferably employed to inflate the impermeable membrane871 since the incompressibility of liquids allows the impermeable membrane 871 to expand more uniformly and consistently. The impermeable membrane 871 may expand radially as illustrated in FIGURE 25, or directionally, depending on its method of manufacture and attachment to the dispensing application tube 821. As the impermeable membrane 871 expands outward for expanded affixing (see FIGURE 25 ) due to the pressure of the fluid or fluid, an empty space is dissected adjacent to the provided site. When the void space is large enough, liquid, air or another fluid may be released from the inner space 873 to allow the impermeable membrane 871 to assume the relaxed position. The impermeable membrane 871 may then be ruptured as explained above and the reduced pressure applying apparatus 861 is inserted adjacent the tissue site.

Referring to FIGURE 25A, if the permeable membrane 871 is employed primarily to dissect the tissue adjacent the tissue site, the impermeable membrane871 may be sealably attached to the delivery tube 821 such that the internal space 873 communicates fluidly with a secondary lumen or tubing 891 associated with or attached to the dispensing delivery tube 821. Secondary lumen 891 may be employed to apply a liquid, air, or other fluid to the inner space 873 to place the impermeable membrane 871 in the expanded position. After dissection, the permeable membrane 871 may be relaxed and ruptured as described above with reference to FIGURE 24.

Referring to FIGURE 26, a reduced pressure delivery system 911 according to an embodiment of the present invention includes a dispensing delivery tube 921 having a tapered distal end 943 that is configured to radially outwardly flex to an open position such that the diameter distal end 943 is substantially equal to or greater than the inner diameter in other parts of the tube 921. Open placement of the distal end 943 is shown schematically in FIGURE 26 by the discontinuous lines 937.

Dispensing delivery tube 921 additionally includes a passageway in which a reduced pressure application apparatus 961 is similar to the other reduced pressure application apparatus described in the present invention. The reduced pressure delivery apparatus 961 includes a flexible barrier 965 and / or cellular material 967 which is preferably wrapped, folded, or otherwise compressed around a reduced depression delivery tube 969 to reduce the cross-sectional area of the pressure application apparatus. 961 inside the 921 manifold application pipe passage.

An impermeable membrane 971 having an inner space 973 is disposed around the reduced depression application apparatus 961 such that the reduced pressure applying apparatus 961 is contained within the inner portion 973 of the impermeable membrane 971. The permeable membrane 971 includes a glue seal 977 at one end of the impermeable membrane 971 to provide an alternative method of removing the reduced pressure applying apparatus 961 from the impermeable membrane 971. The permeable membrane 971 may be sealedly connected at one end to the dispensing application tube 921 such that the internal space 973 of the permeable membrane 971 is in fluid communication with the dispensing application passage 921. Alternatively, the waterproof membrane 971 may be attached to a separate control tube (not shown) which communicates fluidly as an internal space 973.

Similar to the impermeable membrane 871 of FIGURE 23, the impermeable membrane 971 may be capable of preventing fluid transmission such that the permeable membrane 971 can assume at least one of a compressed position, a relaxed position, and an expanded position. Since the procedures for placing the impermeable membrane 971 in a compressed position and an expanded position are similar to those for the impermeable membrane 871, only the different process of removing the reduced pressure delivery apparatus 961 is described.

The reduced pressure delivery apparatus 961 is applied to the tissue site within the impermeable membrane 971 and then positioned correctly using endoscopy, ultrasound, fluoroscopy, auscultation, palpation, or any other appropriate localization technique. The permeable membrane 971 may include radiopaque markers 981 which enhance visualization of the 971 impermeable membrane under fluoroscopy prior to its removal. The reduced depression application apparatus 961 is then pushed through the distal end 943 of the dispensing application tube 921. Reduced pressure applied to the interior space 973 may be loosened to place the impermeable membrane 971 in the relaxed position. The reduced pressure delivery apparatus 961 is then sprayed through the glue seal 977 to remove the waterproof membrane 971.

With reference to FIGURE 26A, a reduced pressure application system 985 according to an embodiment of the present invention cannot include a distribution application tube similar to the distribution application tube 921 of FIGURE 26. Instead, the reduced pressure application system 985 it may include a guide wire 987, a reduced pressure application tube 989, and a reduced pressure application apparatus 991. The reduced pressure application apparatus 991 includes a plurality of flow channels that are fluidly connected to the reduced pressure application tube 989. Instead of using an independently distributed application tube to apply the reduced pressure application apparatus 991, the reduced pressure application apparatus 991 and the reduced depression application tube 989 are placed on the guide wire 987, which is percutaneously guided to a site. 993.Perferably, the guide wire 987 and the reduced depression 98 9 penetrate the patient's skin through a sterile sheath. By guiding the reduced pressure delivery tube 989 and the reduced pressure delivery apparatus 991 along the guidewire 987, the reduced depression application apparatus 991 can be placed in the tissue site 993 to allow percutaneous application of the low pressure tissue treatment.

Since the reduced pressure delivery apparatus 991 is not confined within a dispensing delivery tube during application to the tissue site 993, it is preferable to hold the reduced pressure application apparatus 991 in a compressed position during application. If a resilient adhesive is employed as a low pressure application apparatus 991, a soluble biocompatible adhesive may be applied to the foam and the compressed foam. Upon arrival at the tissue site, body fluids or other fluids applied through the reduced pressure delivery tube 989 dissolve the adhesive, allowing the foam to expand in contact with the tissue site. Alternatively, the reduced pressure application apparatus 991 may be formed from a dry compressed hydrogel. The hydrogel absorbs moisture after application to the tissue site 993, allowing expansion of the reduced pressure application apparatus 991. Yet another reduced pressure application apparatus 991 may be made of a thermoactive material (e.g. polyethylene glycol) that expands on the endowed site 993 when exposed to heat from the patient's body. In yet another embodiment, a compressed reduced depression 991 delivery apparatus may be applied to the provided site 993 in a dissolvable membrane.

Referring to FIGURE 27, a compressed pressure delivery system 1011 according to an embodiment of the present invention includes a dispensing delivery tube 1021 having a distal end 1043 that is introduced through a patient's tissue to reach a tissue site 1025. Tissue site 1025 may include a void 1029 that is associated with a wound or other defect, or alternatively, a vacuum may be created by dissection, including the dissection techniques described in the present invention.

After placing the distal end 1043 into the void 1029 adjacent the tissue site 1025, an injectable, pourable or flowable reduced pressure delivery apparatus 1035 is applied through the dispensing tube 1021 to the tissue site 1025. The reduced pressure 1035 preferably occurs in a fluid state during tissue application to the site, and then upon arrival forms a plurality of flow channels for the distribution of reduced pressure or fluids. In some cases, the flowable material may harden into a solid state upon arrival at the endowed site through a drying process, a dry process, or another chemical or physical reaction. In other cases, the flowable material may form an in situ foam after application to the tissue site. Still other materials may occur in a gel-like state at the tissue site 1025, but still have a plurality of flow channels for reduced pressure application. The amount of the reduced pressure application apparatus 1035 applied to the provided site 1025 may be sufficient to fully or partially fill the void 1029. The reduced depression application apparatus 1035 may include aspects of a distributor and a support structure. As a dispenser, the reduced pressure delivery apparatus 1035 includes a plurality of open pores or cells that may be formed in the material after application to the void 1029. The open pores or cells communicate with each other, thereby creating a plurality of flow channels. Flow channels are employed to apply and distribute the reduced pressure to the tissue site 1025. As a support structure, the reduced pressure application apparatus 1035 is bioresorbable and serves as a substrate on top of which new tissue can grow.

In one embodiment, the reduced depression delivery apparatus 1035 may include pore formers such as NaCl or other salts which are distributed throughout a gellid or viscous. After the liquid or viscous gel is applied to the tissue site 1025, the void-conforming material 1029 is then cured as a solid mass. Water-soluble pore transformers of NaCl dissolve in the presence of body fluids, leaving an interconnected compositing structure, or flow channels. The reduced pressure and / or fluid is applied to the flow channels. As new tissue develops, the tissue grows in the pores of the reduced pressure delivery apparatus 103 5, and then finally replaces the reduced pressure delivery apparatus 1035 as it degrades. In this particular example, the 1035 reduced pressure delivery apparatus serves not only as a dispenser but also as a support structure for new tissue growth.

In another embodiment, the reduced depression delivery apparatus 1035 is an alginate mixed with 400 pm mannose granules. Pore or granule formers may be dissolved by local body fluids or irrigation or other fluids applied to the reduced pressure delivery apparatus 1035 at the tissue site. Upon the dissolution of the pores or granules, the spaces previously occupied by the pores or granules become voids that are interconnected with other voids to form flow channels within the reduced pressure delivery apparatus1035.

The use of pore formers for creating flow channels in a material is effective, but it also forms pores and flow channels that are limited in size to approximately the particle size of the selected pore former. Instead of pore formers, a chemical reaction may be employed to create larger pores due to the formation of gaseous by-products. For example, in one embodiment, a flowable material may be applied to fabric 1025 sites containing sodium bicarbonate and citric acid particles (non-stoichiometric amounts may be employed). When the flowable material forms a foam or solid in situ, the body fluids initiate an acid-base reaction between sodium bicarbonate and citric acid. The resulting carbon dioxide gas particles are produced which create pores and flow channels throughout the reduced pressure application apparatus 1035 larger than the techniques that are based on pore former dissolution.

Transformation of the reduced pressure application apparatus 1035 from a liquid or viscous gel to a solid or foam may be caused by pH, temperature, light, or a reaction with body fluids, chemicals or other substances applied to the tissue site.

Transformation can also occur by mixing multiple reactive components. In one embodiment, the reduced pressure application apparatus 1035 is prepared by selecting bioresorbable microspheres made of any absorbable polymer. The microspheres are dispersed in a solution containing a photoinitiator and a hydrogel forming material such as hyaluronic acid, collagen, or polyethylene glycol with photoreactive groups. The microsphere-gel mixture is exposed to light for a brief time to partially crosslink the hydrogel and immobilize the hydrogel on the microspheres. Excess solution is drained, and microspheres are then dried. The microspheres are applied to the tissue site upon injection or disposal, and upon application the mixture absorbs moisture and the hydrogel coating becomes hydrated. The mixture is then again exposed to light, which crosslinks the microspheres, creating a plurality of flow channels. The crosslinked microspheres then serve as a dispenser for applying reduced pressure to the tissue site and as a porous support structure to promote new detained growth.

In addition to the foregoing embodiments described in the present invention, the reduced pressure delivery apparatus 1035 may be made from a variety of materials including, without limitation, decalcium phosphate, collagen, alginate, cellulose, or any other equivalent material that may be applied to the a site, such as a gas, liquid, gel, paste, potea, paste, suspension, or other flowable material, and which may form multiple flow passages in fluid communication as a tissue site. The flowable material may also include particulate solids, such as granules, which may flow through the dispensing application tube 1021 if the particulate solids are sufficiently small in size. Materials that are applied to the tissue site in a flowable state may polymerize or turn into gelin-situ.

As described above, the reduced pressure application apparatus 1035 may be injected or discharged directly into the void 1029 adjacent to the tissue site 1025. Referring to FIGURE 27A, the dispensing application tube 1021 may include a permeable or semi-permeable membrane 1051 at the distal end. 1043 of the dispensing delivery tube 1021. The membrane 1051 includes an internal space 1055 that fluidly communicates with a secondary lumen 1057 attached to the dispensing application tube 1021. The dispensing application tube 1021 is guided to the tissue site 1025 by a guide wire. 1061.The reduced pressure delivery apparatus 1035 may be injected or discharged through the secondary lumen 1057 to fill the inner space 1055 of the membrane 1051. When fluid or gel fills the membrane 1051, the membrane 1051 expands to fill the void 1029 of way that the membrane is in contact with the site of the fabric1025. As membrane 1051 expands, membrane 1051 may be employed to dissect additional tissue adjacent to or near tissue site 1025. Membrane 1051, if impermeable, may be physically ruptured and removed, leaving behind reduced depression 1035 Alternatively, membrane 1051 may be made of a dissolvable material that dissolves in the presence of body fluids or biocompatible solvents that may be applied to membrane 1051. If membrane 1051 is semi-permeable, membrane 1051 may remain on site. The semipermeable membrane 1051 enables communication of the reduced pressure and possibly other fluids to the tissue site 1025.

Referring to FIGURE 28, a method 1111 of administering a reduced pressure tissue treatment to a tissue site includes in 1115 the surgical insertion of a dispenser adjacent to the tissue site, wherein the dispenser has a plurality of projections extending from a flexible barrier. to create a plurality of flow channels between projections. The dispenser is positioned 1111 such that at least a portion of the projections is in contact with the tissue site. At 1123, a reduced pressure is applied through the distributor to the provided site.

Referring to FIGURE 29, a method 1211 of administering a reduced pressure tissue treatment to a tissue site includes in 1215 the percutaneous insertion of a dispenser adjacent to the tissue site. The dispenser may include a plurality of projections extending from a flexible barrier to create a plurality of flow channels between the projections. Alternatively, the dispenser may include cellular material that has a plurality of flow channels within the cellular material. Alternatively, the dispenser may be formed of an injectable or disposable material that is applied to the tissue site and forms a plurality of flow channels upon reaching the provided site. At 1219, the dispenser is positioned such that at least part of the flow channels is in fluid communication with the tissue site. A reduced pressure is applied to the tissue site through the distributor in 1223.

Referring to FIGURE 30, a method 1311 of administering a reduced pressure tissue treatment to a tissue site includes in 1315 the percutaneous insertion of a tube that has a passageway through a patient tissue to place a distal end of the adjacent tube at the site of the tissue. fabric. In 1319, a tube-associated balloon may be inflated to dissect tissue adjacent to tissue site, thereby creating an empty space. At 1323, a dispenser is applied through the passageway. The dispenser may include a plurality of projections extending from a flexible barrier to create a plurality of flow channels between the projections. Alternatively, the dispenser may include cellular material that has a plurality of flow channels within the cellular material.

Alternatively, the dispenser may be formed of an injectable or disposable material that is applied to the provided site as described above with reference to FIGURE 27. The dispenser is positioned in the void space 1327 such that at least a portion of the outflow channels is in communication. fluid with the tissue site. In 1331, a reduced pressure is applied to the tissue site through the dispenser through a reduced depression delivery tube or any other application means.

Referring to FIGURE 31, a method 1411 of administering a reduced pressure tissue treatment to a tissue site includes in 1415 the percutaneous insertion of a tube having a passage through a patient tissue to place a distal end of the tube adjacent the site. of the fabric. In 1423, a dispenser is applied by passing to the tissue site within an impermeable sheath, wherein the impermeable sheath in 1419 is subjected to a reduced first pressure less than an ambient pressure of the sheath. In 1427, the sheath is ruptured to place the dispenser in contact with the tissue site. In 1431, a second reduced pressure is applied through the distributor to the tissue site.

Referring to FIGURES 32 and 33, a reduced pressure delivery apparatus 1511 according to an embodiment of the present invention includes a hip orthopedic prosthesis 1515 to replace the existing femoral head of a patient's femur 1517. The hip prosthesis 1515 includes a stem portion 1521 and a head portion 1525. The stem portion 1521 is elongated for insertion into an enlarged passageway 1529 on a shaft of the femur 1517. A porous coating 1535 is disposed around the shaft portion and preferably. Constructed of sintered hearth ceramic or metal. Alternatively, a cellular material which has a porous characteristic may be arranged around the stem portion. A plurality of flow channels 1541 are arranged within the stem portion 1521 of the hip prosthesis 1515 such that the flow channels 1541 are in fluid communication with the porous liner 1535. A connection port 1545 is fluidly connected to the flow channels 1541, wherein the port is configured for releasable connection to a reduced pressure delivery tube 1551 and a reduced pressure delivery source 1553. The flow channels 1541 are employed to apply reduced pressure to the porous lining 1535 and / or the bone surrounding the prosthesis. pelvis 1515 after implantation. The flow channels may include a main feed line 1543 which fluidly communicates with several side branch lines 154 7 which communicate with the porous lining 1535. The branching side lines 1545 may be orientated normally with respect to the main feed line 1543 as illustrated in FIGURE 32, or may be oriented at angles to the main feed line 1543. An alternative method for distributing reduced pressure includes providing a basin prosthesis. , and filling the internal space of the prosthesis with (preferably) an open cell cellular material that has the ability to communicate fluidly with porous coating 1535.

Referring more specifically to FIGURE 33, hip prosthesis 1515 may also include a second plurality of flow channels 1561 within the stem portion 1521 to provide a fluid to the porous lining 1535 and / or the bone surrounding the hip prosthesis 1515. Fluid may include filtered air or other gases, antibacterial agents, antiviral agents, cell growth promoting agents, irrigation fluids, chemically active fluids, or any other fluids. If it is desired to introduce multiple fluids into the bone surrounding the hip prosthesis 1515, additional fluid communication passages may be provided. A connection port 1565 is fluidly connected to flow channels 1561, wherein port 1565 is configured for releasable connection to a fluid application tube 1571 and a fluid application source 1573. Flow channels 1561 may include a feed line. 1583 which communicates fluidly with several branched side lines 1585 which communicate with the porous lining 1535. The side branch lines 1585 may be oriented normally relative to the main feed line 1583 as illustrated in FIGURE 33, or may be oriented at angles relative to each other. to the 1583 main power line.

Applying the reduced pressure to the first plurality of flow channels 1541 and applying fluid to the second plurality of flow channels 1561 may be accomplished by separate tubes such as the reduced pressure application tube 1551 and the fluid application tube 1571. Alternatively, a tube having multiple lumens as described hereinbefore may be employed to separate the communication passages to apply reduced pressure and fluid. It should also be noted that when provision of separate fluid communication passages within the hip prosthesis 1515 is preferable, the first plurality of flow channels 1541 could be employed to apply reduced pressure and fluid to the bone surrounding the hip prosthesis 1515.

As described above, the application of reduced pressure to bone tissue promotes and accelerates the growth of new bone tissue. By using the debacia prosthesis 1515 as a distributor to apply reduced pressure to the bone area surrounding the hip prosthesis, femoral recovery 1517 is faster, and the hip prosthesis 1515 more successfully integrates with the bone. The use of the second plurality of flow channels 1561 to disengage the bone surrounding the hip prosthesis 1515 improves the successful generation of new bone around the prosthesis.

After applying reduced pressure through the bowl prosthesis 1515 for a selected amount of time, the reduced pressure application tube 1551 and fluid application tube 1571 may be disconnected from the connecting ports 1545, 1565 and removed from the patient body, preferably without a surgically invasive procedure. The connection between the connecting ports 1545, 1565 and the tubes 1551, 1571 may be a manually releasable connection which is effected by applying an axially oriented tensioning force to the tubes 1551, 1571 on the outside of the patient body. Alternatively, the connecting ports 1545, 1565 may be bioresorbable or dissolvable in the presence of selected chemicals or fluids such that release of the 1551, 1571 tubes may be achieved by exposing the connecting ports 154 5, 1565 to fluid or chemical compound. Tubes 1551, 1571 may also be made of a bioresorbable material that dissolves over a period of time or an activated material that dissolves in the presence of a particular chemical or other substance.

The reduced pressure delivery source 1553 may be provided outside the patient's body and may be connected to the reduced pressure delivery tubing 1551 to apply the reduced pressure to the hip prosthesis 1515. Alternatively, the reduced pressure application font 1553 may be implanted within the patient body. both onboard and near the hip prosthesis 1515. Placing the reduced depression 1552 application source into the patient's body eliminates the need for a percutaneous fluid connection. The implanted 1553 reduced pressure application source may be a traditional pump that is operatively connected to the 1541 flow channels. The pump may be powered by a battery that is implanted within the patient, or may be powered by an external battery that is electrically connected and percutaneously to the pump. The pump can also be directly driven by a chemical reaction that applies reduced pressure and circulates fluids through flow channels 1541, 1561.

Although only the stem portion 1521 and the head portion 1525 of the hip prosthesis 1515 are illustrated in FIGURES 32 and 33, it should be noted that the flow channels and the means for applying the reduced pressure tissue treatment described in the present invention could be applied to any pelvic prosthesis component 1515 that contacts the bone or other tissue, including, for example, the acetabular cup.

Referring to FIGURE 34, a method 1611 for affixing a patient's joint includes in 1615 implanting a prosthesis into a bone adjacent the joint. The prosthesis could be a hip prosthesis as described above or any other prosthesis that helps in restoring patient joint mobility. The prosthesis includes a plurality of flow channels configured to communicate fluidly as bone. In 1619, reduced pressure is applied to the bone through the plurality of flow channels to improve the integration of the prosthesis.

Referring to FIGURES 35 and 36, a reduced pressure application apparatus 1711 in accordance with an embodiment of the present invention includes a orthopedic fixation device 1715 for securing a patient bone 1717 including a fracture defect 1719 or the like. Orthopedic fixation device 1715 illustrated in FIGURES 35 and 36 is a plate having a plurality of passages 1721 for anchoring orthopedic fixation device 1715 to bone 1717 with screws 1725, pins, screws, or other fasteners. A porous coating 1735 may be disposed on a surface of the orthopedic fixation device 1715 that must contact the bone 1717. The porous coating is preferably constructed of sintered hearth ceramic or metal. Alternatively, a porous material having the porous characteristic could be disposed between the bone 1717 and the orthopedic fixation device 1715. A plurality of flow channels 1741 are disposed within the orthopedic fixation device 1715 such that the flow channels 1741 are in communication. porous coating 1735. A 1745 connecting port is fluidly connected to the 1741 flow channels, where the port is configured for connection to a 1751 low pressure application tube and a 1753 reduced pressure application source. 1741 are employed to apply reduced pressure to the porous lining 1735 and / or the bone surrounding the orthopedic fixation device 1715 after fixation of the orthopedic fixation device 1715 to the bone 1717. Flow channels 1741 may include a main feed line 1743 which communicates. fluidly with several branched lateral lines 174 7, communicating with the porous lining 1735. Side branch lines 174 7 may be oriented normally relative to the main feed line 1743 as illustrated in FIGURE 35, or may be oriented at angles relative to the main feed line 1743. An alternative method for distributing the reduced pressure includes provision of a hollow orthopedic fixation device, and filling the internal space of the orthopedic fixation device with (preferably) open cell cellular material that can communicate with the porous lining 1735.

the orthopedic clamping device 1715 may be a plate as shown in FIGURE 35, or alternatively it may be a clamping device such as a glove, brace, support, or any other device that is employed to stabilize a portion of the bone. The orthopedic fixation device 1715 may also consist of fasteners employed to attach prosthetic devices or other orthopedic devices or implanted tissues (e.g., bone or cartilage tissues), provided that the fasteners include flow channels for the application of reduced pressure to or adjacent to the surrounding tissue. fasteners. Examples of such fasteners may include pins, screws, dowels, or any other suitable fastener.

Referring more specifically to FIGURE 36, the orthopedic fixation device 1715 may also include a second plurality of flow channels 1761 within the orthopedic fixation device 1715 to provide a porous lining fluid 1735 and / or the bone surrounding the orthopedic fixation device 1715. Such fluid could include filtered air or other gases, antibacterial agents, antiviral agents, cell growth promoting agents, irrigation fluids, chemically active agents, or any other fluids. If it is desired to introduce multiple fluids into the bone surrounding the orthopedic fixation device 1715, additional fluid communication passages may be employed. A 1765 port port is fluidly connected to flow channels 1761, wherein port 1765 is configured for connection to a 1771 fluid delivery tube and a 1773 fluid application source. 1761 flow channels may include a main feed line. 1783 which fluidly communicates with several side branch lines 1785, which communicate with the porous coating 1735. The branched side lines 1785 may be oriented normally relative to the main feed line 1783 as illustrated in FIGURE 33, or may be oriented at angles to the main feed line 1783.

The application of reduced pressure to the first plurality of flow channels 1741 and the application of fluid to the second plurality of flow channels 1761 may be carried out by separate tubes, such as the reduced depression application tube 1751 and the fluid application tube 1771. A tube having multiple lumens as described earlier in the present invention may be employed to separate the communication passages to apply reduced pressure and fluid. It should also be noted that when the provision of separate fluid communication passages within the orthopedic fixation device 1715 is preferable, the first plurality of flow channels 1741 could be employed to apply reduced pressure and fluid to the bone adjacent the orthopedic deflection device 1715.

The use of orthopedic fixation device 1715 as a dispenser to apply reduced pressure to the bone area adjacent to the orthopedic fixation device 1715 accelerates and improves recovery of bone defect 1719. The use of the second plurality of flow channels 1761 to communicate fluid to the The bone surrounding the orthopedic fixation device 1715 improves the successful generation of our new near the orthopedic fixation device.

Referring to FIGURE 37, a method 1811 for the accuracy of a bone defect in a bone includes in 1815 bone attachment using an orthopedic deflection device. The orthopedic fixation device includes a plurality of flow channels disposed within the orthopedic fixation device. In 1819, reduced pressure61 / 70 is applied to the bone defect through the plurality of flow channels.

Referring to FIGURE 38, a method 1911 for administering reduced pressure tissue treatment to a tissue site includes in 1915 the positioning of a dispenser having a plurality of flow channels such that at least a portion of the flow channels become in communication. fluid with the tissue site. A reduced pressure is applied in 1919 to the tissue site through the flow channels, and a fluid is applied in 1923 to the site provided through the flow channels.

Referring to FIGURE 39, a 2011 method for administering reduced pressure tissue treatment to a tissue site includes in 2015 positioning a distal end of a delivery tube adjacent the tissue site. In 2019 a fluid is applied through the dispensing application tube to the provided site. The fluid may fill an empty space adjacent to the tissue site and become a solid dispenser that has a plurality of flow channels in fluid communication with the tissue site. A reduced pressure is applied at 2023 to the tissue site through the solid distributor flow channels.

Referring to FIGURES 40-48, a reduced pressure application system 2111 includes a main distributor 2115 having a flexible wall 2117 surrounding a main flow passage 2121. Flexible wall 2117 is connected at a proximal end 2123 to a reduced pressure application tube 2125. Since the reduced pressure application tube shape 2125 will typically be round in cross-section, and since the main distributor shape 2115 in cross-section may be other than round (i.e. rectangular in FIGURES 4 0-45 etriangular). 46-48), a transition region 2129 is formed between the reduced pressure delivery tube 2125 and the main distributor 2115. The main distributor 2115 may be adhesively bonded to the reduced depression application tube 2125, connected by using other half-stops such as fusion or insert molding, or can be alternatively connected integrally through co-extrusion. The reduced pressure delivery tube 2125 applies reduced pressure to the main manifold 2115 for distribution at or near the tissue site.

A blockage prevention member 2135 is positioned within the main manifold to prevent collapse of the manifold 2115, thereby blocking the main flow passage 2121 during application of reduced pressure. In one embodiment, the lockout prevention member 213 may consist of a plurality of projections 2137 (see FIGURE 44) disposed on an inner surface 2141 of the flexible wall 2117 and extending into the main flow passageway 2121. In another embodiment, the member The locking block 2135 may consist of a single ridge or multiple ridges 2145 disposed on the inner surface 2141 (see FIGURES 40 and 41). In yet another embodiment, lock prevention member 2135 may include a cell material 2149 disposed within the main flow passage, such as that illustrated in FIGURE 47. Lock prevention member 2135 may be any material or structure that may be inserted into the housing. flow passageway or which may be integrally or otherwise attached to flexible wall 2117. Blockage prevention member 2135 may prevent total collapse of flexible wall 2117, while still permitting fluid flow through the main flow passage 2121. Flexible wall 2117 it further includes a plurality of openings 2155 through flexible wall 2117 communicating with the main flow passage 2121. Openings 2155 allow the reduced pressure applied to the main flow passage 2121 to be delivered to the provided site. The openings 2155 may be selectively positioned around the circumference of the distributor 2115 to preferably direct the vacuum application. For example, in FIGURE 51, the openings may be placed facing the bone, facing the overlying tissue, or both.

The reduced pressure delivery tube 2125 preferably includes a first conduit 2161 which has at least one outlet fluidly connected to the main flow passage 2121 for applying reduced pressure to the main flow passage 2121. A second conduit 2163 may also be nailed to purge the flow path. main stream 2121 and first conduit 2161 with a fluid to prevent or release blockages caused by wound exudate and other fluids extracted from the tissue site. Second conduit 2163 preferably includes at least one outlet positioned next to at least one of the main flow passage 2121 and at least one outlet of first conduit 2161.

Referring more specifically to FIGURES 40 and 41, in the reduced pressure delivery system 2111, second conduit 2163 may include multiple conduits for purging main flow passage 2121 and first conduit 2161. Although the end of flexible wall 2117 is opposed to the end attached to the tube Pressure reducing pressure 2125 may be open as illustrated in FIGURE 40, it has been found that if the flexible wall end2117 is capped this can improve the performance and reliability of the purge function. Preferably, an interior space 2171 is provided between the capped end of the flexible wall and the end of the second conduit 2163. The anterior space 2171 allows a purging fluid to accumulate during the purge process, which helps to propel the purge fluid through the flow passage. 2121 and for the first conduit 2161.

Also shown in FIGURE 41 is the divider serving as the lockout preventer member 2135. The centrally located divider forks the main flow passage 2121 into two chambers, which allows continued operation of the main distributor 2115 if one of the chambers becomes blocked and the purge cannot release the lock.

Referring to FIGURES 49 and 50, a reduced pressure application system 2211 includes a main distributor 2215 that is integral with a reduced depression application tube 2217. The reduced pressure application tube 2217 includes a central lumen 2223 and a plurality of auxiliary lumens. 2225. While auxiliary lumens 2225 may be employed to measure pressure at or near the tissue site, auxiliary lumens 2225 may also be employed to purge central lumen 2223 to prevent or release blockages. A plurality of openings 2231 communicate with the central lumen 2223 to distribute the reduced pressure applied by the central lumen 2223. As shown in FIGURE 50, it is preferable that the apertures 2231 do not penetrate auxiliary lumens 2225. In FIG. 50 also the tapered end of the application tube is shown. pressure gap, which creates an anterior space 2241 beyond the end of the auxiliary lumens 2225. If the fabric, support structures, or other materials have to couple the end of the reduced pressure delivery tube 2217 during reduced pressure application, the anterior space 2241 should continue. allowing the purge fluid to be applied to the central lumen 2223.

In operation, the reduced pressure delivery systems 2111, 2211 of FIGURES 40-50 may be applied directly to a tissue site to distribute the reduced pressure to the tissue site. The low profile shape of the main distributors is highly desirable for the percutaneous installation and removal techniques described in the present invention. Similarly, main dispensers may also be surgically inserted.

Referring to FIGURE 51, main distributors 2115, 2215 may be employed together with a secondary distributor 2321. In FIGURE 51, secondary distributor 2321 includes a two-layer felt mat. The first layer of the secondary distributor 2321 is brought into contact with a bone tissue site that includes a bone fracture. The main distributor 2115 is placed in contact with the first layer, and the second layer of the secondary distributor 2321 is placed on top of the main distributor 2115 and the first layer. Secondary distributor 2321 allows fluid communication between the main distributor 2115 and the tissue site, yet prevents direct contact between the tissue site and the main distributor 2115.

Preferably, the secondary distributor 2321 is bioabsorbable, which allows the secondary distributor 2321 to remain in place after reduced pressure treatment. Upon completion of the reduced pressure treatment, the main distributor 2115 may be removed from the secondary distributor layers without almost any disturbance to the tissue site. In one embodiment, the main dispenser may be coated with a lubricating material or a hydrogel forming material to facilitate removal between the layers.

The secondary distributor preferably serves as a support structure for new tissue growth. As a support structure, the secondary distributor may comprise at least one selected material from the group of polylactic acid, polyglycolic acid, polycapralactone, polyhydroxy butyrate, polyhydroxy valerate, polydioxanone, polyorthoesters, polyphosphaenes, polyurethanes, collagen, hyaluronic acid, chitosan aphosphate, chitosan calcium, decalcium sulfate, calcium carbonate, bioglass, stainless steel, titanium, tantalum, allografts, and autografts.

The purge function of the reduced depression application systems 2111, 2211 described above may be employed with any of the dispensers described in the present invention. The ability to purge a manifold or a reduced pressure delivery duct prevents the formation of blockages that impair the delivery of reduced pressure. These blockages typically form when pressure near the tissue site reaches equilibrium and fluid flow around the tissue site is slowed down. It has been found that the purge of the distributor and the reduced pressure air duct by a selected amount of time within a selected range helps prevent release of blockages.

More specifically, air is applied through a second duct separate from a first duct that applies reduced pressure. A second conduit outlet is preferably close to the manifold or a first conduit outlet. Although air may be pressurized and "pushed" out of the second conduit, air is preferably drawn through the second conduit by reduced pressure at the tissue site. It has been found that applying air for two (2) seconds at sixty (60) second intervals during application of the reduced pressure is sufficient to prevent blockages from forming in many cases. This purge schedule provides enough to sufficiently move the fluids within the manifold and the first duct, while preventing too much air from being introduced. The introduction of too much air, or "too much" interval air, will result in the reduced depression system not being able to return to the target reduced pressure between bleed cycles. The amount of time selected to apply bleed fluid and the selected interval at which purge fluid is applied will typically vary based on the design and size of system components (eg, pump, piping, etc.). However, air must be applied in a quantity and at a such that they are sufficiently high to sufficiently release the locks while allowing the total target pressure to be recovered between bleed cycles.

Referring to FIGURE 52, in an illustrative embodiment, a reduced pressure delivery system 2411 includes a distributor 2415 fluidly connected to a first conduit 2419 and a second conduit 2423. First conduit 2419 is connected to a reduced pressure source 24 29 to provide reduced pressure to distributor 2415. Second conduit 2423 includes an outlet 2435 positioned in fluid communication with distributor 2415 and close to an outlet of first conduit 2419. Second conduit 2423 is fluidly connected to a valve 2439, which may allow communication between the second conduit 2423 and the environment when the valve is placed in an open position. Valve 24 39 is operatively connected to a controller2453 which can control valve opening and closing 24 3 9 to regulate the purge of second conduit with ambient air to prevent blockages within distributor 2415 and first conduit 2419.

It should be noted that any fluid, including liquids or gases, could be employed to practice the purge techniques described in the present invention. Although the thrust force for the purge fluid is preferably the dragging of the reduced pressure at the tissue site, the fluid could similarly be applied by a fluid application device similar to that discussed with reference to FIGURE 9.

Administration of the reduced pressure tissue treatment to a tissue site according to the systems and methods described in the present invention may be accomplished by applying sufficient reduced pressure to the provided site and then that sufficient reduced pressure is maintained for a selected period of time. . Alternatively, the reduced pressure that is applied to the tissue site may be cyclic in nature. More specifically, the amount of reduced depression applied may be varied according to a selected time cycle. Yet another method of applying reduced pressure may vary the amount of reduced depression randomly. Similarly, the rate or volume of fluid applied to the tissue site may be constant, cyclic or random in nature. Fluid application, if cyclic, may occur during application of the reduced pressure, or may occur during periods of time when the reduced pressure is not being applied. Although the amount of reduced pressure applied to a tissue site typically varies according to the condition. of the tissue site and the circumstances under which pressure tissue treatment is administered, the reduced pressure will typically be from about -5 mm Hg to -500 mm Hg, but more preferably about -5 mm Hg to -300 mm. from Hg.

Although the systems and methods of the present invention have been described with reference to tissue growth and healing in human patients, it should be recognized that these systems and methods for applying reduced pressure tissue treatment can be employed in any living organism in which one wishes to promote growth or healing of the tissue. Similarly, the systems and methods of the present invention may be applied to any tissue, including, without limitation, fat tissue, fat tissue, muscle tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. Although tissue healing may be a focal point for the application of the reduced pressure tissue treatment as described in the present invention, the application of the reduced pressure tissue treatment, especially to tissues located below a patient's skin, may also be employed to generate tissue growth. in tissues that are not sick, defective, or damaged. For example, it may be desired to employ skin implant techniques to apply reduced pressure tissue treatment for additional tissue growth in a tissue site that can then be harvested. The harvested tissue may be transplanted to another tissue site to replace diseased or damaged tissue, or alternatively the tissue may be transplanted to another patient.

It is also important to note that the reduced pressure application apparatus described in the present invention may be employed in conjunction with the support structure material to increase the growth and rate of decrease of new tissue. The support structure material could be placed between the tissue site and the reduced pressure application apparatus, or the reduced pressure application apparatus itself could be made of bioresorbable material which serves as a support structure for new tissue growth.

It should be apparent from the foregoing that an invention has been shown to have significant advantages. Although the invention is shown only in some of its forms, it is not limited but is susceptible to various changes and modifications without departing from the same character.

Claims (46)

1. REDUCED PRESSURE APPLICATION SYSTEM FOR THE APPLICATION OF REDUCED PRESSURE TISSUE TREATMENT TO A TISSUE SITE, characterized in that it comprises: a primary manifold having a flexible wall that surrounds a primary flow passage and is adapted to be placed near the fabric site, wherein the flexible wall includes an inner surface which comprises a plurality of projections extending from at least a portion of the inner surface and into the primary flow passage, and the flexible wall also includes a plurality of openings through the flexible wall and in communication. with the primary flow passage, a first conduit fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage and plurality of openings; and a second conduit having at least one outlet in the vicinity of the primary flow passage or at least one outlet of the first conduit to remove blockages in at least one outlet of or near the first conduit. SYSTEM according to Claim 1, characterized in that the first and second conduits are part of a multi-lumen tube. SYSTEM according to claim 2, characterized in that the flexible wall and the multiple lumen tube are coextruded. A system according to claim 1, characterized in that the first and second conduits are part of a multi-lumen tube, the flexible wall is connected at one end of the multi-lumen tube; and the primary flow passage is capped at a flexible wall end opposite the end connected to the multi-lumen tube. SYSTEM according to Claim 1, characterized in that the second conduit is positioned at least partially within the wall. A system according to claim 1, characterized in that the flexible wall is a medical grade silicone polymer. A system according to claim 1, characterized in that the flexible wall is substantially rectangular in cross section. System according to Claim 1, characterized in that the flexible wall is substantially cylindrical along at least one part of its axial length. A system according to claim 8, characterized in that the substantially cylindrical flexible wall comprises a 360 degree arc. SYSTEM according to Claim 1, characterized in that the projections prevent the obstruction of the primary flow passage by preventing the flexible appearance from completely collapsing during the application of the reduced pressure through the primary flow passage. SYSTEM according to claim 1, characterized in that the site of the comprised tissue is selected from the group of adipose tissue, tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, and ligaments. A system according to claim 1, further comprising a secondary manifold adapted to be positioned adjacent to the primary manifold and to communicate the reduced pressure of the primary manifold to the tissue site. A system according to claim 12, characterized in that the secondary distributor is bioabsorbable. A system according to claim 12, characterized in that the secondary distributor is a felt mat. A system according to claim 12, characterized in that the secondary distributor is a support structure and comprises at least one material selected from the group of polylactic acid, polyglycolic acid, polycaprolactone, polyhydroxy butyrate, polyhydroxyvalerate, polydioxanone, polyorthoesters, polyphosphazenes, polyurethanes, collagen, hyaluronic acid, chitosan, apatite hydroxy, calcium phosphate, decal sulfate, calcium carbonate, bioglass, stainless steel, titanium, tantalum, allografts, and autografts. 16. REDUCED PRESSURE APPLICATION SYSTEM FOR APPLICATION OF REDUCED PRESSURE TISSUE TREATMENT TO A TISSUE SITE, characterized in that it comprises: a primary manifold having a pareflexible flow that surrounds a primary flow passage and is adapted to be placed in close proximity to the tissue site, wherein the flexible wall includes a plurality of openings through the flexible wall and in communication with the primary flow passage, a cellular material positioned within the primary flow passage, wherein the cellular material has a plurality of flow channels; fluidly connected conduit to the primary flow passage to apply reduced pressure through the primary flow passage, the cellular material, and the plurality of openings; and a second conduit having at least one outlet in the vicinity of the primary flow passage or at least one outlet of the first conduit to remove blockages in at least one outlet of or near the first conduit. A system according to claim 16, characterized in that the first and second conduits are part of a multi-lumen tube. System according to Claim 17, characterized in that the flexible wall and the multi-lumen tube are co-extruded. A system according to claim 16, characterized in that the first and second conduits are part of a multi-lumen tube: the flexible wall is connected at one end of the multi-lumen tube; and the primary flow passage is capped at a flexible wall end opposite the end connected to the multi-lumen tube. A system according to claim 16, characterized in that the second conduit is positioned at least partially within the flexible wall. A system according to claim 16, characterized in that the flexible wall is a medical grade silicone polymer. A system according to claim 16, characterized in that the flexible wall is reinforced to prevent collapse under reduced pressure. System according to Claim 16, characterized in that the flexible wall is substantially rectangular in cross-section. System according to Claim 16, characterized in that the flexible wall is substantially cylindrical along at least one part of its axial length. A system according to claim 24, characterized in that the substantially cylindrical flexible wall subtends an arc of 360 degrees. A system according to claim 16, characterized in that the cellular material prevents the obstruction of the primary flow passage by preventing the flexible appearance from completely collapsing during the application of the reduced pressure through the primary flow passage. A system according to claim 16, characterized in that the site of the comprised tissue is selected from the group of adipose tissue, tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, and ligaments. A system according to claim 16 wherein the cellular material is a polyurethane foamed foam. A system according to claim 16, further comprising a secondary manifold adapted to be positioned adjacent to the primary manifold and to communicate the reduced pressure of the primary manifold to the tissue site. A system according to claim 29, characterized in that the secondary distributor is bioabsorbable. System according to Claim 29, characterized in that the secondary distributor is a felt mat. A system according to claim 29, characterized in that the secondary distributor is a support structure and comprises at least one material selected from the group of polylactic acid, polyglycolic acid, polycaprolactone, polyhydroxy butyrate, polyhydroxy valerate, polydioxanone, polyorthoesters, polyphosphazenes. , polyurethanes, collagen, hyaluronic acid, chitosan, apatite hydroxy, calcium phosphate, decalcium sulfate, calcium carbonate, bioglass, stainless steel, titanium, tantalum, allografts, and autografts. 33. REDUCED PRESSURE APPLICATION SYSTEM FOR APPLICATION OF REDUCED PRESSURE TISSUE TREATMENT TO THE FABRIC SITE, characterized in that it comprises: a primary manifold having a paredeflexible flow that surrounds a primary flow passage and is adapted to be placed near the tissue site, wherein the primary distributor includes a blockage prevention member positioned within the primary flow passage, and the flexible wall includes a plurality of openings through the flexible wall and in communication with the primary flow passage; a secondary distributor positioned adjacent the distributor primary and adapted to contact the tissue site such that the secondary distributor communicates fluidly with the primary distributor but is adapted to prevent contact between the primary distributor and the tissue site; It is a first conduit fluidly connected to the primary flow passage to apply reduced pressure through the primary flow passage and the plurality of openings. A system according to claim 33, characterized in that the locking prevention member consists of a plurality of projections disposed on an internal surface of the flexible wall and extending into the primary flow passage. A system according to claim 33, characterized in that the blocking prevention member is a cellular material disposed within the primary flow passage. A system according to claim 33, characterized in that the secondary distributor is bioabsorbable. A system according to claim 33, characterized in that the secondary distributor is a felt mat. A system according to claim 33, characterized in that the secondary distributor is a support structure and comprises at least one selected material from the group of polylactic acid, polyglycolic acid, polycaprolactone, polyhydroxy butyrate, polyhydroxy valerate, polydioxanone, polyorthoesters, polyphosphazenes. , polyurethanes, collagen, hyaluronic acid, chitosan, apatite hydroxy, calcium phosphate, decalcium sulfate, calcium carbonate, bioglass, stainless steel, titanium, tantalum, allografts, and autografts. 39. METHOD FOR PROMOTING TISSUE GROWTH IN A TISSUE SITE, characterized by the fact that it comprises: the surgical positioning of a primary distributor near the tissue site, where the primary distributor has a flexible wall surrounding a primary flow passage, and the wall The flexible delivery includes a plurality of openings through the flexible wall and in communication with the primary flow passage, and the primary distributor also includes a locking prevention member positioned within the primary flow passage; the surgical positioning of a secondary distributor in contact with the tissue site of manner in which the secondary distributor communicates fluidly with the primary distributor but prevents contact between the primary distributor and the tissue site; and applying reduced pressure to the provided site through the primary flow passage, plurality of openings, and secondary distributor. Method according to claim 39, characterized in that the blocking prevention member is a cellular material disposed within the primary outflow passage, and the cellular material has a plurality of flow channels. A method according to claim 39, characterized in that the locking prevention member consists of a plurality of projections extending from an internal flexible wall surface and to the primary flow passage. System according to Claim 39, characterized in that the secondary distributor is a felt mat. A system according to claim 39, characterized in that the secondary distributor is a support structure and comprises at least one material selected from the group of polylactic acid, polyglycolic acid, polycaprolactone, polyhydroxy butyrate, polyhydroxy valerate, polydioxanone, polyorthoesters, polyphosphazenes. , polyurethanes, collagen, hyaluronic acid, chitosan, apatite hydroxy, calcium phosphate, decalcium sulfate, calcium carbonate, bioglass, stainless steel, titanium, tantalum, allografts, and autografts. 44. The method of claim 39 further comprising: percutaneously removing the primary dispenser after the reduced pressure tissue treatment is completed. A method according to claim 39, further comprising: percutaneously removing the primary dispenser after completion of the reduced pressure tissue treatment; and wherein the secondary distributor is bioabsorbable. A method according to claim 39, further comprising purging primary flow passage with ambient air to prevent blockages within the primary flow passage.