Devices and methods for treating and closing wounds with negative pressure

Abstract

The present invention relates to a negative pressure wound closure system and methods for using such a system. Preferred embodiments of the invention facilitate closure of the wound by preferentially contracting to provide for movement of the tissue.

What is claimed is: 
     
         1 . A wound therapy device for use in treating a wound with negative pressure, comprising:
 a porous wound treatment material for removal of wound exudate from a wound under negative pressure, the porous wound treatment material extending in lateral and longitudinal directions defining a horizontal plane; and   a plurality of vertically extending members in the porous wound treatment material, the vertically extending members being spaced apart and made of a more rigid material than the porous wound treatment material;   wherein upon application of negative pressure to the porous wound treatment material, the porous wound treatment material is configured to contract in the horizontal plane with the vertically extending members reducing vertical movement of the porous wound treatment material, and wherein the vertically extending members are dispersed within, and separated by portions of, the porous wound treatment material.   
     
     
         2 . The wound therapy device of  claim 1 , wherein the porous wound treatment material comprises a foam that surrounds each of the plurality of vertically extending members. 
     
     
         3 . The wound therapy device of  claim 1 , wherein the porous wound treatment material extends between each of the plurality of vertically extending members and compresses in the horizontal plane upon application of negative pressure. 
     
     
         4 . The wound therapy device of  claim 1 , wherein the porous wound treatment material comprises a plurality of slits or areas in which the vertically extending members are inserted. 
     
     
         5 . The wound therapy device of  claim 1 , wherein the porous wound treatment material is positioned between the vertically extending members and is flexible such that the vertically extending members compress towards each other in the horizontal plane when the porous wound treatment material is positioned within a wound bed under negative pressure. 
     
     
         6 . The wound therapy device of  claim 1 , wherein the plurality of vertically extending members are adhered to the porous wound treatment material. 
     
     
         7 . The wound therapy device of  claim 1 , wherein the vertically extending members comprise columns or tiles that are vertically rigid or semi-rigid to inhibit the porous wound treatment material from collapsing vertically. 
     
     
         8 . The wound therapy device of  claim 7 , wherein the columns or tiles comprise a rigid plastic, or a semi-rigid material, or a rigid foam or a felted flexible foam. 
     
     
         9 . The wound therapy device of  claim 7 , wherein the columns have a circular cross-section, each column having a diameter in a range from about 5 mm to about 10 mm. 
     
     
         10 . The wound therapy device of  claim 7 , wherein spacing between the columns or tiles is in a range of from about 1 mm to about 20 mm. 
     
     
         11 . The wound therapy device of  claim 1  wherein the porous wound treatment material comprises a pad, the pad including channels or openings. 
     
     
         12 . The wound therapy device of  claim 1 , wherein the porous wound treatment material comprises an open cell foam and has a thickness between about one inch and about two inches. 
     
     
         13 . The wound therapy device of  claim 1  further comprising a thin, flexible, and permeable wound contact layer positioned between a wound surface of the wound and the porous wound treatment material, the wound comprising an open wound or a closed wound. 
     
     
         14 . The wound therapy device of  claim 1  wherein the porous wound treatment material has a rectangular or oval shape. 
     
     
         15 . The wound therapy device of  claim 1  wherein the porous wound treatment material extends in the longitudinal direction and the lateral direction, the vertically extending members further extending along the longitudinal direction, the porous wound treatment material comprising a compressible foam that is compressed between surfaces of the vertically extending members. 
     
     
         16 . The wound therapy device of  claim 1  wherein the vertically extending members have a uniform height. 
     
     
         17 . The wound therapy device of  claim 1  wherein the porous wound treatment material comprises a pressure responsive foam such that the foam has a first volume at a first pressure and a second, smaller volume at a second pressure different from the first pressure. 
     
     
         18 . A negative pressure wound therapy system, comprising:
 the porous wound treatment material of  claim 1 ; and   a wound cover to form a seal over the wound, the wound cover configured to be placed over the porous wound treatment material.   
     
     
         19 . The system of  claim 18 , further comprising a connection for connecting the wound cover to a source of negative pressure configured to apply a negative pressure between about −20 mmHg and about −200 mmHg, the wound cover comprising a drape. 
     
     
         20 . The system of  claim 18 , further comprising a negative pressure source configured to be connected to the wound cover to provide negative pressure over a therapeutic range of pressure to the porous wound treatment material when placed within a wound bed to fill the wound. 
     
     
         21 . A method of making a negative pressure wound therapy device comprising:
 forming a porous foam wound treatment material that is compressible in a horizontal plane; and   inserting vertically extending members into separated regions of the porous foam material to reduce vertical movement of the porous foam wound treatment material.   
     
     
         22 . The method of  claim 21  further comprising forming slits or areas in the porous foam wound treatment material to receive the vertically extending members. 
     
     
         23 . The method of  claim 21  wherein the vertically extending members comprise a rigid plastic, a semi-rigid material, a rigid foam or a felted foam. 
     
     
         24 . The method of  claim 21  wherein the porous foam wound treatment material has an oval or rectangular shape. 
     
     
         25 . The method of  claim 21  wherein the porous foam wound treatment material contracts more in a first direction in the horizontal plane than in a second direction in the horizontal plane.