Directed tissue growth employing reduced pressure

• US 20030225347A1
• Filed: 06/03/2002
• Published: 12/04/2003
• Est. Priority Date: 06/03/2002
• Status: Abandoned Application

• Current Assignee: Wake Forest University Health Sciences
• Original Assignee: Wake Forest University
• Inventors: Morykwas, Michael J., Webb, Lawrence X., Argenta, Louis C.
• Application Number:
  US10/161,076
• Publication Number:
  US 20030225347A1
• Time in Patent Office: Days
• US Class Current: 601/6
• CPC Class Codes: A61B 17/88 Osteosynthesis instruments; Methods or means for implanting or extracting internal or external fixation devices A61B17/7074 takes precedence
• CPC Class Codes: A61F 2013/00927 with biological activity, e.g. enzymes for debriding wounds or others, collagen or growth factors
• CPC Class Codes: A61H 9/005 Pneumatic massage

Abstract

A tissue growth apparatus and method are provided for growing tissue by applying a tissue growth medium to the tissue and applying reduced, sub-atmospheric pressure at the growth medium and the tissue in a controlled manner for a selected time period. The application of reduced pressure at the growth medium and tissue promotes growth of the tissue within the tissue growth medium. The apparatus includes a tissue cover sealed over a tissue site. The apparatus also includes a tissue growth medium located beneath the tissue cover and in contact with the tissue to be grown. A vacuum pump supplies suction within the tissue cover over the tissue site to provide reduced pressure to the tissue and the tissue growth medium.

Claims

1. An appliance for administering a reduced pressure treatment to promote directed growth of a tissue comprising:

(a) a cover adapted to cover and enclose a tissue to be grown and adapted to maintain reduced pressure at the site of the tissue;

(b) a seal adapted to seal the cover about the tissue;

(c) reduced pressure supply means for connection to a source of suction, the reduced pressure supply means cooperating with the cover to supply the reduced pressure beneath the cover; and

(d) a bone substitute material adapted to promote tissue growth therein, the bone substitute material being located between the tissue and the cover.

2. An appliance according to claim 1 wherein the bone substitute material comprises a bioabsorbable material.

3. An appliance according to claim 1 wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

4. An appliance according to claim 1 wherein the cover comprises a flexible sheet.

5. An appliance according to claim 1 wherein the bone substitute material comprises a porous material.

6. An appliance according to claim 1 wherein the seal includes an adhesive material on the cover adapted to secure the cover to the tissue to be grown.

7. An appliance according to claim 1 wherein the reduced pressure supply means includes a segment of tubing embedded within the bone substitute material.

8. An apparatus for growing a tissue, comprising:

vacuum means for creating a sub-atmospheric pressure at a tissue to be grown;

sealing means operatively associated with the vacuum means for maintaining the sub-atmospheric pressure at the tissue by contacting the region surrounding the tissue; and

a bone substitute material for positioning at the tissue within the sealing means and adapted to promote tissue growth therein.

9. An apparatus according to claim 8 wherein the bone substitute material comprises a bioabsorbable material.

10. An apparatus according to claim 8 wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

11. An apparatus according to claim 8, wherein the sealing means includes a flexible sealing rim in contact with the region surrounding the tissue.

12. An apparatus according to claim 8, wherein the sealing means includes a flexible polymer sheet overlying the bone substitute material, the polymer sheet having adhesive on at least a surface facing the tissue to attach and seal the polymer sheet to the region surrounding the tissue.

13. An apparatus according to claim 8, wherein the sealing means comprises a fluid-impermeable cover.

14. An apparatus according to claim 8 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.5 and 0.98 atmospheres to the tissue.

15. An apparatus according to claim 8 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.73 and 0.95 atmospheres to the tissue.

16. An apparatus according to claim 8 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.8 and 0.9 atmospheres to the tissue.

17. An apparatus according to claim 8, wherein the vacuum means operates continuously.

18. An apparatus according to claim 8, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction.

19. An apparatus according to claim 18 wherein the vacuum means provides periods of application and non-application of suction with the ratio of duration of application period to non-application period between about 1:

10 and 10;

1.

20. An apparatus according to claim 19 wherein the duration of the application period is about 5 minutes.

21. An apparatus according to claim 20 wherein the duration of the non-application period is about 2 minutes.

22. An apparatus for applying sub-atmospheric pressure to a tissue to be grown beneath a fluid-impermeable seal comprising:

a bone substitute material for positioning beneath the seal configured to overlie the tissue such that the sub-atmospheric pressure is maintained within the bone substitute material and is applied to the tissue; and

a flexible tube having an inlet end inserted into the bone substitute material and an outlet end for extending from beneath the seal for supplying the sub-atmospheric pressure.

23. An apparatus according to claim 22 wherein the bone substitute material comprises a bioabsorbable material.

24. An apparatus according to claim 22 wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

25. An apparatus for growing a tissue, comprising:

a bone substitute material configured to overlie a tissue to be grown;

a fluid-impermeable cover overlying the bone substitute material, the cover adapted to form a seal with the region surrounding the tissue for maintaining sub-atmospheric pressure beneath the cover; and

a tubular member having a first end inserted within a portion of the bone substitute material and having a second end extending from beneath the cover to a location external to the cover for supplying sub-atmospheric pressure beneath the cover.

26. An apparatus according to claim 25 wherein the bone substitute material comprises a bioabsorbable material.

27. An apparatus according to claim 25 wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

28. An apparatus according to claim 25 wherein the first end of the tubular member is embedded within the bone substitute material.

29. An apparatus for growing a tissue, comprising:

vacuum means for creating a sub-atmospheric pressure at a tissue to be grown;

sealing means operatively associated with the vacuum means for maintaining the sub-atmospheric pressure at the tissue by contacting the region surrounding the tissue; and

a bone substitute material for positioning at the tissue within the sealing means, the bone substitute material having a pore size sufficiently large to permit tissue growth therein.

30. An apparatus according to claim 29, wherein the bone substitute material comprises a bioabsorbable material.

31. An apparatus according to claim 29, wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

32. An apparatus according to claim 29, wherein the sealing means includes a flexible sealing rim in contact with the region surrounding the tissue.

33. An apparatus according to claim 29, wherein the sealing means includes a flexible polymer sheet overlying the bone substitute material, the polymer sheet having adhesive on at least a surface facing the tissue to attach and seal the polymer sheet to the region surrounding the tissue.

34. An apparatus according to claim 29, wherein the vacuum means operates continuously.

35. An apparatus according to claim 29, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction.

36. An apparatus according to claim 35, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction with the ratio of duration of application period to non-application period between about 1:

10 and 10;

1.

37. An apparatus according to claim 36 wherein the duration of the application period is about 5 minutes.

38. An apparatus according to claim 37 wherein the duration of the non-application period is about 2 minutes.

39. An apparatus for growing a tissue comprising:

a bone substitute material configured to overlie the tissue;

a cover overlying the bone substitute material, the cover adapted to form a seal with the region surrounding the tissue for maintaining a sub-atmospheric pressure beneath the cover;

a tubular member having a first end inserted within a portion of the bone substitute material and having a second end extending from beneath the cover to a location external to the cover; and

a vacuum source connected with the second end of the tubular member for supplying the sub-atmospheric pressure to the tissue.

40. An apparatus according to claim 39 wherein the bone substitute material comprises a bioabsorbable material.

41. An apparatus according to claim 39 wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

42. An apparatus according to claim 39 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.5 and 0.98 atmospheres to the tissue.

43. An apparatus according to claim 39 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.73 and 0.95 atmospheres to the tissue.

44. An apparatus according to claim 39 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.8 and 0.9 atmospheres to the tissue.

45. An apparatus according to claim 39 wherein the first end of the tubular member is embedded within the bone substitute material.

46. An apparatus for growing a tissue comprising:

a bioabsorbable scaffold material configured to overlie the tissue, the scaffold material having a pore size sufficiently large to permit tissue growth therein;

an open-cell foam section in communication with the scaffold material;

a cover overlying the scaffold material and the foam section, the cover adapted to form a seal with the region surrounding the tissue for maintaining a sub-atmospheric pressure beneath the cover; and

a tubular member having a first end inserted within a portion of the foam section and having a second end extending from beneath the cover to a location external to the cover for supplying the sub-atmospheric pressure beneath the cover.

47. An apparatus according to claim 46 wherein the scaffold material comprises a skin substitute material.

48. An apparatus according to claim 46 wherein the scaffold material comprises a collagen layer.

49. An appliance for administering a reduced pressure treatment to promote directed growth of a tissue comprising:

(a) a cover adapted to cover and enclose a tissue to be grown and adapted to maintain reduced pressure at the site of the tissue;

(b) a seal adapted to seal the cover about the tissue;

(c) reduced pressure supply means for connection to a source of suction, the reduced pressure supply means cooperating with the cover to supply the reduced pressure beneath the cover; and

(d) a bioabsorbable scaffold material for promoting tissue growth therein configured to be located between the tissue and the cover.

50. An appliance according to claim 49 wherein the scaffold material comprises a skin substitute material.

51. An appliance according to claim 49 wherein the scaffold material comprises a collagen layer.

52. An appliance according to claim 49 wherein the cover comprises a flexible sheet.

53. An appliance according to claim 49 wherein the seal includes an adhesive material on the cover adapted to secure the cover to the tissue to be grown.

54. An appliance according to claim 49 comprising an open-cell foam section in communication with the scaffold material.

55. An appliance according in claim 54 wherein the reduced pressure supply means includes a segment of tubing embedded within the foam section.

56. An apparatus for growing a tissue, comprising:

vacuum means for creating a sub-atmospheric pressure at a tissue to be grown;

sealing means operatively associated with the vacuum means for maintaining the sub-atmospheric pressure at the tissue by contacting the region surrounding the tissue; and

a bioabsorbable scaffold material for positioning at the tissue within the sealing means and adapted to promote tissue growth therein.

57. An apparatus according to claim 56 wherein the scaffold material comprises a skin substitute material.

58. An apparatus according to claim 56 wherein the scaffold material comprises a collagen layer.

59. An apparatus according to claim 56, wherein the sealing means includes a flexible sealing rim in contact with the region surrounding the tissue.

60. An apparatus according to claim 56, wherein the sealing means comprises a fluid-impermeable cover.

61. An apparatus according to claim 56, wherein the sealing means includes a flexible polymer sheet overlying the scaffold material, the polymer sheet having adhesive on at least a surface facing the tissue to attach and seal the polymer sheet to the region surrounding the tissue.

62. An apparatus according to claim 56 comprising an open-cell foam section in communication with the scaffold material.

63. An apparatus according to claim 62 wherein the vacuum means includes a segment of tubing embedded within the foam section.

64. An apparatus according to claim 56, wherein the vacuum means operates continuously.

65. An apparatus according to claim 56, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction.

66. An apparatus according to claim 65 wherein the vacuum means provides periods of application and non-application of suction with the ratio of duration of application period to non-application period between about 1:

10 and 10;

1.

67. An apparatus according to claim 66 wherein the duration of the application period is about 5 minutes.

68. An apparatus according to claim 67 wherein the duration of the non-application period is about 2 minutes.

69. An apparatus according to claim 56 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.5 and 0.98 atmospheres to the tissue.

70. An apparatus according to claim 56 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.73 and 0.95 atmospheres to the tissue.

71. An apparatus according to claim 56 wherein the vacuum means supplies a sub-atmospheric pressure between about 0.8 and 0.9 atmospheres to the tissue.

72. An apparatus for applying sub-atmospheric pressure to a tissue to be grown beneath a fluid-impermeable seal comprising:

a bioabsorbable scaffold material for positioning beneath the seal configured to overlie the tissue; and

a flexible tube having an inlet end inserted into the scaffold material and an outlet end for extending from beneath the seal for supplying a sub-atmospheric pressure to the tissue.

73. An apparatus according to claim 72 wherein the scaffold material has a pore size sufficiently large to permit tissue growth therein.

74. An apparatus according to claim 72 wherein the scaffold material comprises a skin substitute material.

75. An apparatus according to claim 72 wherein the scaffold material comprises collagen.

76. An apparatus for growing a tissue, comprising:

a bioabsorbable scaffold material configured to overlie a tissue to be grown;

an open-cell foam section in communication with the scaffold material;

a fluid-impermeable cover overlying the scaffold material and the foam section, the cover adapted to form a seal with the region surrounding the tissue for maintaining sub-atmospheric pressure beneath the cover; and

a tubular member having a first end inserted within a portion of the foam section and having a second end extending from beneath the cover to a location external to the cover for supplying sub-atmospheric pressure beneath the cover.

77. An apparatus according to claim 76 wherein the scaffold material comprises a skin substitute material.

78. An apparatus according to claim 77 wherein the scaffold material comprises a collagen layer.

79. An apparatus for growing a tissue, comprising:

vacuum means for creating a sub-atmospheric pressure at a tissue to be grown;

sealing means operatively associated with the vacuum means for maintaining the sub-atmospheric pressure at the tissue by contacting the region surrounding the tissue; and

a bioabsorbable scaffold material for positioning at the tissue within the sealing means, the scaffold material having a pore size sufficiently large to permit tissue growth therein.

80. An apparatus according to claim 79, wherein the scaffold material comprises a skin substitute material.

81. An apparatus according to claim 79, wherein the scaffold material comprises collagen.

82. An apparatus according to claim 79, wherein the sealing means includes a flexible sealing rim in contact with the region surrounding the tissue.

83. An apparatus according to claim 79, wherein the cover includes a flexible polymer sheet overlying the scaffold material, the polymer sheet having adhesive on at least a surface facing the tissue to attach and seal the polymer sheet to the region surrounding the tissue.

84. An apparatus according to claim 79 wherein the vacuum means includes a segment of tubing embedded within the scaffold material.

85. An apparatus according to claim 79, wherein the vacuum means operates continuously.

86. An apparatus according to claim 79, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction.

87. An apparatus according to claim 86, wherein the vacuum means operates cyclically to provide periods of application and non-application of suction with the ratio of duration of application period to non-application period between about 1:

10 and 10;

1.

88. An apparatus according to claim 87 wherein the duration of the application period is about 5 minutes.

89. An apparatus according to claim 88 wherein the duration of the non-application period is about 2 minutes.

90. An apparatus for growing a tissue comprising:

a bioabsorbable scaffold material configured to overlie the tissue;

a cover overlying the scaffold material, the cover adapted to form a seal with the region surrounding the tissue for maintaining a sub-atmospheric pressure beneath the cover;

a tubular member having a first end inserted within a portion of the scaffold material and having a second end extending from beneath the cover to a location external to the cover; and

a vacuum source connected with the second end of the tubular member for supplying the sub-atmospheric pressure to the tissue.

91. An apparatus according to claim 90 wherein the scaffold material comprises a skin substitute material.

92. An apparatus according to claim 90 wherein the scaffold material comprises a collagen layer.

93. An apparatus according to claim 90 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.5 and 0.98 atmospheres to the tissue.

94. An apparatus according to claim 90 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.73 and 0.95 atmospheres to the tissue.

95. An apparatus according to claim 90 wherein the vacuum source supplies a sub-atmospheric pressure between about 0.8 and 0.9 atmospheres to the tissue.

96. A method of growing a tissue comprising the steps of:

(a) providing a tissue growth medium proximate the tissue;

(b) applying a sub-atmospheric pressure to a tissue to be grown; and

(c) maintaining the sub-atmospheric pressure until the tissue has progressed toward a selected stage of growth within the tissue growth medium.

97. The method according to claim 96, wherein the maintaining of the sub-atmospheric pressure is conducted in alternating periods of application and non-application of the sub-atmospheric pressure.

98. The method according to claim 97, wherein each of the alternating periods is about 5 minutes.

99. The method according to claim 96, wherein the tissue growth medium comprises a bioabsorbable scaffold material.

100. The method according to claim 99, wherein the scaffold material comprises a skin substitute material.

101. The method according to claim 99, wherein the scaffold material comprises a collagen layer.

102. The method according to claim 96, wherein the tissue growth medium comprises a bone substitute material.

103. The method according to claim 102, wherein the bone substitute material comprises a bioabsorbable material.

104. The method according to claim 102, wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

105. A method for growing a tissue comprising the steps of:

(a) applying a sub-atmospheric pressure to a tissue to be grown, wherein the applying step comprises the steps of;

(i) placing a tissue growth medium in contact with a tissue to be grown;

(ii) locating a cover over the tissue;

(iii) sealing the periphery of the cover about the tissue; and

(iv) operably connecting the cover with a vacuum system for producing the sub-atmospheric pressure; and

(b) maintaining the sub-atmospheric pressure until the tissue has progressed toward a selected stage of growth within the tissue growth medium.

106. The method according to claim 105, wherein the maintaining of the sub-atmospheric pressure is conducted in alternating periods of application and non-application of the sub-atmospheric pressure.

107. The method according to claim 106, wherein each of the alternating periods is about 5 minutes.

108. The method according to claim 105, wherein the tissue growth medium comprises a bioabsorbable scaffold material.

109. The method according to claim 108, wherein the scaffold material comprises a skin substitute material.

110. The method according to claim 108, wherein the scaffold material comprises a collagen layer.

111. The method according to claim 105, wherein the tissue growth medium comprises a bone substitute material.

112. The method according to claim 111, wherein the bone substitute material comprises a bioabsorbable material.

113. The method according to claim 111, wherein the bone substitute material comprises at least one of calcium sulfate, calcium phosphate, a bioglass, or a ceramic.

114. A method for growing new bone tissue from existing bone tissue comprising the steps of:

(a) placing a bone substitute material in contact with the existing bone tissue to provide a matrix in which to grow new bone tissue;

(b) locating a cover over the existing bone tissue and the bone substitute material to form a sealed chamber at the bone tissue and the bone substitute material;

(c) providing a subatmospheric pressure within the chamber; and

(d) maintaining the sub-atmospheric pressure within the chamber until new bone tissue of a desired amount is grown within the bone substitute material.