Skin grafting devices and methods

• US 20050234485A1
• Filed: 03/30/2005
• Published: 10/20/2005
• Est. Priority Date: 02/16/2001
• Status: Active Grant

• Current Assignee: Solventum Intellectual Properties Company (Solventum Corp.)
• Original Assignee: KCI Licensing Incorporated (3M Company)
• Inventors: Sanders, Teryl Blane, Seegert, Charles, Johnson, Royce W., Boccuti, A. David, Gentile, Andrew Nicholas, Griffey, Sy
• Granted Patent: US 7,666,192 B2
• Time in Patent Office: Days
• US Class Current: 606/172
• CPC Class Codes: A61B 17/322 Skin grafting apparatus
• CPC Class Codes: A61B 2017/320064 with tissue or sample retaining means
• CPC Class Codes: A61M 1/784 by filtering, sterilising or disinfecting the exhaust air, e.g. swellable filter valves
• CPC Class Codes: A61M 1/90 Negative pressure wound therapy devices, i.e. devices for applying suction to a wound to promote healing, e.g. including a vacuum dressing
• CPC Class Codes: A61M 1/98 Containers specifically adapted for negative pressure wound therapy
• CPC Class Codes: A61M 27/00 Drainage appliance for wounds or the like , i.e. wound drains, implanted drains negative pressure wound therapy devices A61M1/90; implements for holding wound open A61B17/02 ; middle ear drainage A61F11/202

Abstract

The present invention provides skin grafting and devices that comprise a systematic approach to the process of skin grafting, i.e., harvesting, post-excision processing and application of donor skin and pre and post-graft treatment of the recipient site.

Claims

1. A skin-harvesting device, comprising:

a base, comprising a base plate with a proximal end, a distal end, two side ends and defining a window adjacent to the proximal end, and adapted during use to be pressed against a harvest site; and

a cutting frame, comprising a blade housing adapted to house a blade at a predetermined angle therein, wherein said blade is aligned traverse to the side ends and generally parallel to the proximal end and wherein the predetermined angle of the blade relative to the proximal end forms an oblique angle, and an adjustable thickness plate coupled to the cutting frame and adapted to raise or lower to vary thickness of any material cut by the blade.

2. The skin-harvesting device of claim 1, further comprising a motor having an axle coupled through the cutting frame to the blade and adapted to oscillate the blade.

3. The skin-harvesting device of claim 2, further comprising a power source connected to the motor.

4. The skin-harvesting device of claim 3, wherein the power source comprises a battery pack connected to the motor.

5. The skin-harvesting device of claim 2, further comprising an ergonomic cover housing the cutting frame and motor, the ergonomic cover defining a skin-graft retrieval area to allow during use access to skin collected after harvesting.

6. The skin-harvesting device of claim 1, further comprising internal slide rails formed at the side ends of the base and track fixtures positioned on lateral ends of the cutting frame, the track fixtures being adapted to slide in the internal slide rails of the base and thereby translate the cutting frame along the base.

7. The skin-harvesting device of claim 1, further comprising external slide rails formed at side ends of the base and track fixtures positioned on lateral ends of the cutting frame, the track fixtures being adapted to slide in the external slide rails of the base and thereby translate the cutting frame along the base.

8. The skin-harvesting device of claim 1, wherein the base has an open end to allow the cutting frame to be removed from or placed within the base.

9. The skin-harvesting device of claim 1, wherein the blade is coupled to the blade housing via thermoplastic welding or via fasteners.

10. The skin-harvesting device of claim 1, further comprising tab portions positioned along the proximal end of the base adjacent the window to provide a user with an area to apply pressure to the base during use of the device.

11. The skin-harvesting device of claim 1, further comprising grips positioned on the base adapted to allow a user an area to apply pressure to the base during use of the device.

12. The skin-harvesting device of claim 1, further comprising grips positioned on the cover adapted to provide a user an area to grip the cover to translate the cover within the base during use of the device.

13. The skin-harvesting device of claim 1, further comprising a plurality of ridges formed on the skin-facing surface of the adjustable thickness plate, the plurality of ridges being adapted to during use grip the skin prior to incision.

14. The skin-harvesting device of claim 1, wherein the base further comprises a plurality of ridges formed on the skin-facing surface of the base adjacent the window adapted during use to grip the skin adjacent the base window.

15. The skin-harvesting device of claim 1, further comprising at least one fastener coupled through the cutting frame to the adjustable depth plate adapted to raise and lower the adjustable depth plate.

16. The skin-harvesting device of claim 1, further comprising a skin-depth wheel or a skin-depth slide positioned on the cover and coupled to the adjustable thickness plate to raise or lower the adjustable thickness plate with respect to the skin during use.

17. The skin-harvesting device of claim 16, further comprising indicia printed on the cover adjacent the skin-depth wheel or skin-depth slide to indicate the depth of the adjustable thickness plate when the skin-depth wheel is rotated or the skin-depth slide is moved.

18. The skin-harvesting device of claim 1, further comprising a roller wheel positioned before the blade and blade holder and rotating about an axle coupled to the cover, wherein said roller wheel comprises a plurality of teeth about the perimeter of the wheel adapted during use to puncture or hook the skin prior to incision by the blade adapted to secure the skin onto the roller wheel after severance.

31. A method of harvesting skin comprising:

contacting a skin harvest site with the skin-harvesting device of claim 1;

applying pressure to the base of the skin-harvesting device such that skin from the harvest site protrudes through the window in the base plate of said harvesting device;

adjusting the adjustable thickness plate of the harvesting device to press the skin protruding through the window to form a uniform surface substantially parallel to the base;

and harvesting the a split-thickness skin sample by translating the cutting frame along the base of the harvesting device.

98. A kit comprising a skin harvesting device according to claim 1 and a skin processing device according to claim 3, and instructions for use thereof.

19. A device for collecting tissue for skin-grafting, comprising a base plate defining a base window at a forward end thereof and having slide rails positioned at lateral internal edges of the base plate;

a frame base adapted to slide in the slide rails of the base plate;

a frame connected to the frame base;

a plurality of slides coupled along lateral edges of the frame and adapted to engage the slide rails and slide freely therethrough;

base grips positioned along lateral ends of the base plate and adapted to support pressure during use from a user thereon;

an ergonomic cover adapted to encompass the frame and frame base and defining a cover window at a forward end thereof;

cover grips positioned at lateral edges of the cover adapted to allow during use a user to firmly grip the cover and apply pressure thereon during use of the device;

a motor coupled to the frame;

a power source connected to the motor;

a blade holder coupled to a forward section of the frame via a guide pin;

a blade coupled to the blade holder at a predetermined angle;

an adjustable depth plate coupled to the frame adjacent and forward from the blade holder; and

a cam connected to the adjustable depth plate having a cam dial adapted to control the raising and lowering of the adjustable depth plate with respect to the base window.

32. A method of collecting skin for a skin-graft, comprising:

pressing the device of claim 19 against a skin donor such that a uniform surface of donor skin protrudes substantially parallel to the base through the base window;

pressing the adjustable depth plate against the donor skin such that the protruding donor skin is of uniform thickness; and

sliding the frame coupled to the blade holder along the base so as to sever the protruding donor skin.

20. A skin-harvesting device, comprising:

a base defining a base window adapted to be pressed during use against skin to allow the skin to protrude therethrough and to see the skin prior and during incision;

a cover housing a cutting blade, motor connected to the cutting blade, and a power source connected to the motor, the cover being adapted to translate along the base;

the cover defining a skin-graft retrieval area adjacent the cutting blade, which during use supports skin severed by the cutting blade and provides access to the severed skin;

an adjustable depth plate positioned forward of the cutting blade and housed within the cover;

a skin-depth wheel or a skin-depth slider positioned on the cover adjacent the skin-graft retrieval area adapted to provide during use manual control of the adjustable depth plate by a user; and

a switch positioned on the top of the cover for activation and de-activation of the motor.

21. The skin harvesting device of claim 20, wherein said cover housing a cutting blade further comprises a handle-portion having a power switch positioned on an underside thereof, wherein during use said handle-portion is adapted to be gripped by a user during translation of the cover along the base during use of the device.

22. The skin harvesting device of claim 20, further comprising a radius portion surrounding the perimeter of the base adapted to provide during use an area for a user to assist in applying pressure to the device.

23. The skin harvesting device of claim 20, wherein said cover housing a cutting blade further defines at least one depression thereon adapted to conform to a user'"'"'s hand for secure gripping and movement when the cover is translated along the base during use.

24. The skin harvesting device of claim 20, further comprising a plurality of ridges formed on the cover in the skin-graft retrieval area to during use support severed skin thereon.

25. The skin harvesting device of claim 20, further comprising textured ridges positioned on lateral edges of the cover for a user to grip the cover during use and apply a pressure on the cover to translate the cover along the base, said base having an extended area adjacent the window on opposing sides for a user to apply pressure to the base during use of the device.

26. The skin harvesting device of claim 25, further comprising a pair of raised portions on the extended area of the base for a user to apply pressure to the base during use of the device.

27. The skin harvesting device of claim 20, wherein said base further comprises an enlarged portion or tabs adjacent the window on opposing sides for a user to apply pressure to the base during use of the device.

28. The skin harvesting device of claim 20, further comprising external tracks positioned along lateral edges of the base.

29. The skin harvesting device of claim 20, wherein said base further comprises an open end to allow the user to extract the cover from the base during use.

30. The skin harvesting device of claim 20, wherein said cover housing a cutting blade is tubular.

33. A device for cutting skin comprising:

a plurality of circular blades aligned in parallel on a blade shaft; and

a screen comprising a dorsal and a ventral surface, a leading edge and a trailing edge, and plurality of parallel transverse slits disposed therein, wherein said parallel slits are disposed such that they align with said parallel blades and wherein the parallel blades are located on the screen dorsal surface side and protrude through said slits disposed in said screen such that each blade protrudes a distance from said screen ventral surface.

34. The device of claim 33, wherein said screen has a step portion proximal and generally parallel to the trailing edge and located between said trailing edge and the protruding blades, wherein said step portion displaces the screen shape generally towards that side wherein the blade shaft is located, and wherein during use said step portion affects the extrusion of cut skin pieces when a split-thickness-skin graft located on a cutting mat support surface is translated along the ventral surface of said screen in the direction from said leading edge to said trailing edge and said skin is cut by said blades, and wherein said cut skin pieces generally remain in contact with said cutting mat.

35. The device of claim 34, wherein said step portion is a generally right angle step portion.

36. The device of claim 34, wherein said step portion is a generally arc shaped step portion.

37. The device of claim 33, wherein said plurality of circular blades are rotatably disposed on said blade shaft.

38. The device of claim 33, further comprising a plurality of spacers aligned on said blade shaft and wherein one or more spacers are located between each of said plurality of circular blades.

39. The device of claim 34, wherein said screen leading edge and said screen trailing edge are on a generally horizontal plane, and the screen from the leading edge describes a plane at a descending angle and returns to a generally horizontal plane in the general location of the line described by the trailing edge side of the minor arcs described by the protruding blades.

40. A skin processing device, comprising:

a generally rectangular base wherein at a proximal end said base is adapted to couple with the device of claim 34, wherein said blade shaft is placed lateral relative to the base; and

a sled and a removable cutting mat skin support surface adapted to be placed on said sled, wherein during use said sled with said cutting mat is adapted to translate longitudinally along said base;

wherein said circular blades and said sled with said cutting mat are positioned relative to each other such that during use a split thickness skin graft placed on said cutting mat is cut into pieces when said sled is translated along said base.

41. The skin processing device of claim 40, further comprising a handle adapted to translate said sled along said base.

42. The skin processing device of claim 40, wherein said circular blades aligned in parallel on said blade shaft are adapted to couple to said base such that during use they are yieldably biased in a plane perpendicular from said base by the translation of said cutting mat on said sled until a predetermined force is exerted on said cutting mat by said circular blades.

43. The skin processing device of claim 42, wherein said predetermined force is determined by a resistance means.

44. The skin processing device of claim 43, wherein said resistance means comprise a plurality of helical compression springs.

45. The skin processing device of claim 42, wherein said blade shaft and screen are adapted to couple to said base by a detachable housing wherein said detachable housing has a generally rectangular dorsal surface side, two lateral sides and a two longitudinal sides in a generally orthogonal relationship to one another and an open ventral side with two ventral lateral edges adapted to be detachable coupled to the longitudinal edges at the proximal end of said base, and a trailing ventral longitudinal edge and a leading ventral longitudinal edge, wherein both ventral longitudinal edges have recessed portions adapted to couple to said respective screen trailing and leading edges, wherein said ventral trailing longitudinal edge is adjacent to said proximal end of said base, and wherein during use said recessed portions of said housing ventral edges and said coupled screen allow for the translation along said base of said sled such that said cutting mat contacts said circular blades protruding through said screen, and wherein the ends of the blade shaft are adapted to be movably coupled to interior surfaces of said lateral sides of said housing such that during use said blade shaft can be yieldably biased in the plane perpendicular to said base.

46. The skin processing device of claim 45, wherein said predetermined force is determined by the maximal operative compression of two helical compression springs that during use are adapted to exert force on the blade shaft when said blade shaft and said circular blades are yieldably biased in concert by the translation of said cutting mat upon said sled, wherein said force is exerted adjacent to both ends of said blade shaft.

47. The skin processing device of claim 45, wherein each helical compression springs is aligned on a bolt with a proximal end and a distal end, wherein said bolt is aligned perpendicular to said base and the proximal ends of said bolts are adapted to contact said blade shaft wherein said blade shaft is positioned between said bolt proximal end and said base, and wherein the distal ends of said bolts are adapted to contact said helical compression springs, and during use said helical compression springs are adapted to be compressed against said housing dorsal surface side.

48. The skin processing device of claim 40, wherein said cutting mat has a hydrophilic surface.

49. The skin processing device of claim 40, wherein said cutting mat comprises poly-ether block amide resin.

50. The skin processing device of claim 40, wherein the surface of said cutting mat is textured.

51. The skin processing device of claim 40, wherein the surface of said cutting mat is textured with pores comprising a depth of about 35 μ

m to about 75 μ

m.

52. The device of claim 36 wherein the space between said parallel blades is adjustable within the range of about 250 μ

m through about 1500 μ

m, or from the range of about 500 μ

m to about 1000 μ

m.

53. The device of claim 38 wherein said space between said parallel blades is about 250 μ

m, or is about 300 μ

m, is about 400 μ

m, or about 500 μ

m, or about 600 μ

m, or about 700 μ

m, or about 800 μ

m, or about 900 μ

m, or about 1000 μ

m.

54. The device of claim 53, wherein said space between said parallel blades is about 600 μ

m.

55. A skin processing device, comprising:

a generally rectangular base wherein at a proximal end said base is adapted to couple to a skin cutting device comprising;

a plurality of circular blades aligned in parallel on a blade shaft aligned lateral relative to said base; and

a screen comprising a dorsal and a ventral surface, a leading edge and a trailing edge, and plurality of parallel transverse slits disposed therein, wherein said parallel slits are disposed such that they align with said parallel blades and said screen is adapted such that said parallel blades are located on the screen dorsal surface side and protrude through said slits disposed therein such that each blade protrudes an equal distance from said screen ventral surface; and

a sled and a removable cutting mat skin support surface adapted to be placed on said sled, wherein during use said sled with said cutting mat is adapted to translate longitudinally along said base and contact said cutting blades;

wherein said blade shaft is adapted to couple to said base such that during use it is yieldably biased by contact of the circular blades with the cutting mat occasioned by translation of the sled until a predetermined force is exerted on said cutting mat by said circular blades.

56. A cutting device comprising a plurality of blades aligned on a blade shaft, a screen with a plurality of slits disposed therein, wherein said slits are disposed such that they align with said blades and said blades protrude through said slits disposed in said screen, a cutting mat adapted to translate along the surface of the screen wherein the blades protrude, such that during use said blades contact said cutting mat.

57. The cutting device of claim 57, wherein said blades are yieldably biased during use by contact with said cutting mat, wherein said blades are yieldably biased to an extent determined by a predetermined force wherein said force is determined by a resistance means.

58. A method for applying skin particles to a wound site, comprising the steps of:

providing minced skin particles;

suspending the minced skin particles in an physiologically compatible gel or physiologically compatible aqueous solution;

depositing minced skin particles from aqueous suspension onto one surface of a transfer substrate; and

applying the particle-side of the transfer substrate to a wound to allow the minced skin particles to attach to the wound.

59. The method of claim 58, comprising suspending the minced skin particles in a physiologically compatible aqueous solution and further comprising:

placing the minced skin particle suspension into a reservoir with a negative pressure source, the reservoir having a transfer substrate between the suspension and the negative pressure source;

applying negative pressure from the negative pressure source to the suspension to filter the particles from the aqueous solution onto the transfer substrate; and

removing the transfer substrate having particles deposited on one side thereon.

60. The method of claim 58, further comprising:

suspending the minced skin particles in a physiologically compatible aqueous solution and further comprising pouring the minced skin particle suspension through a drain box adapted to capture the minced skin particles;

applying a transfer substrate to the captured minced skin particles such that the minced skin particles are deposited onto the transfer substrate; and

removing the transfer substrate having particles deposited on one side thereon.

61. The method of claim 60, wherein said drain box has a plurality of hooks adapted to capture one or two minced skin particles.

62. The method of claim 60, wherein said drain box has depressions adapted to capture minced skin particles.

63. The method of claim 58, wherein the transfer substrate is a polymer mesh.

64. The method of claim 63, wherein polymer mesh may be included or absorbed by the wound.

65. The method of claim 58, wherein the transfer substrate is a fibrous growth enhancing matrix.

66. The method of claim 58, wherein negative pressure therapy is applied to the wound site subsequent to transfer of skin particles to the wound.

67. The method of claim 58, wherein negative pressure therapy is applied prior to transfer of skin particles to the wound

68. The method of claim 58, wherein the physiologically aqueous solution is phosphate buffered saline.

69. The method of claim 58, wherein said particle-side of the transfer substrate is applied to a wound for a predetermined time.

70. The method of claim 58, wherein the physiologically compatible gel is contained in a first reservoir and optionally the minced skin aqueous suspension is contained in a second reservoir;

and wherein said physiologically compatible gel reservoir and optional second minced skin aqueous suspension are fluidly connected to a dispenser, wherein said dispenser is adapted to deposit the gel and optionally the minced skin aqueous suspension on to a transfer substrate comprising a mesh roll; and

wherein said mesh roll is applied to a wound.

71. The method of claim 70, wherein said mesh roll is disposed in roll form on a roll bracket coupled to said dispenser.

72. The method of claim 71, wherein the surface of the mesh roll with minced skin particles deposited thereon is adhered to the periphery of a wound, and the dispenser with the coupled roll bracket is pulled across the wound, wherein the gel and optionally the minced skin aqueous suspension is extruded from the dispenser and deposited on the mesh roll as it is drawn from the roll bracket by the pulling motion and is applied to the wound.

73. The method of claim 72, further comprising skin particles in suspension in the physiologically compatible gel contained in the first reservoir.

99. The kit of claim 98, further comprising an apparatus suitable for conducting the method of evenly applying nanograft particles to a wound site according to claim 58, and instructions for use thereof.

74. A method of treating a wound comprising:

applying skin nanograft particles to the wound;

applying a pad shaped to conform a wound site;

applying an air-tight seal removeably adhered to said pad; and

applying a negative pressure source in fluid communication with said pad.

75. The method of claim 74, wherein said pad is comprised of bioabsorbable materials.

76. The method of claim 74, wherein said nanograft particles are applied to the wound in a bioabsorbable matrix.

77. The method of claim 76, wherein said pad is an open-cell reticulated porous foam.

78. The method of claim 74, further comprising:

applying a primary dressing over the nanograft particles applied to the wound; and

subsequently applying a pad shaped to conform a wound site.

79. The method of claim 78, further comprising applying a gel to the primary dressing applied to the wound prior to the applying said pad.

80. The method of claim 79, wherein the gel is an antibacterial gel.

81. The method of claim 78, wherein said pad is an open-cell reticulated porous foam.

82. The method of claim 74, further comprising:

applying skin nanograft particles to the wound in a gel;

applying a primary dressing over the nanograft particles; and

subsequently applying a pad shaped to conform a wound site.

83. The method of claim 82, wherein the gel is an antibacterial gel.

84. The method of claim 82, wherein the gel is a gel growth-enhancing matrix.

85. The method of claim 82, wherein said pad is an open-cell reticulated porous foam.

86. The method of claim 74, wherein the nanograft particles are applied in a fibrous growth-enhancing matrix.

87. The method of claim 74, further comprising a flexible tube communicating between said pad and the negative pressure source.

88. The method of claim 87, further comprising a removable canister in fluid communication between said pad and said negative pressure source.

100. The kit of claim 98, further comprising a wound dressing suitable for applying nanografts to a wound site in combination with negative pressure therapy according to claim 74, and instructions for use thereof.

89. A wound dressing comprising a pad adapted for use with negative pressure therapy comprising a foam layer and a matrix layer, wherein nanograft particles are deposited on one surface of the matrix layer such that they are interposed between the foam layer and the matrix layer.

90. The wound dressing of claim 89, wherein said matrix layer comprises an acellular dermal matrix.

91. The wound dressing of claim 89, wherein said foam is an open-cell reticulated porous foam.

92. The wound dressing of claim 89, further comprising a mesh between said foam layer and said nanograft particles.

93. The wound dressing of claim 92, further comprising a non-adherent dressing between said foam layer and said nanograft particles.

94. The wound dressing of claim 89, further comprising an air tight seal removeably adhered to said pad.

95. The wound dressing of claim 94, further comprising negative pressure source in fluid communication with said pad.

96. The wound dressing of claim 95, further comprising a flexible tube communicating between said pad and said negative pressure source.

97. A method of treating a wound comprising applying the wound dressing of claim 89 to a wound site.