Patent Application
20140066956
The present disclosure generally relates to devices and methods for repairing tissue defects. More particularly, the present disclosure relates to processing of harvested skin tissue, processing the skin tissue, reintroducing the processed skin tissue to a defective site, and repairing the defect.
Skin tissue generally comprises three distinct layers including the epidermis, the dermis, and the hypodermis or the sub-cutaneous layer.
The epidermis is the surface layer of the skin tissue and the thickness of the epidermis depends on a number of factors, including age, sex and the location on the body. For example, the skin on the bottom of the foot can be up to 30 cell-layers thick, while the skin on the eyelids is extremely thin. About 90 percent of the cells in the epidermis are keratinocytes, designated because they produce a characteristic fibrous protein called keratin, which provides many of the skin's protective properties. The bottom section of the epidermis, called the basal layer, contains melanocytes, which produce melanin—the skin pigment.
The dermis layer is positioned immediately beneath the epidermis and is connected by a continuous membrane. The dermis forms the thickest section of skin tissue and contains blood vessels, white blood cells, nerve endings, hair follicles, sweat glands and sebaceous glands. Fibroblasts constitute the main cell type in the dermis and they provide a source for collagen and elastin, the fibrous proteins that form the primary structural components of the skin tissue. The dermis provides moisture to the epidermis, produces collagen and elastin to maintain the structural integrity of the skin tissue, and contain glands that produce sebum to keep the skin supple and hydrated.
The hypodermis or the sub-cutaneous layer beneath the dermis, is composed of an extensive network of connective tissue and is imbued with fat cells. It acts as a protective cushion and helps to insulate the body by monitoring heat gain and heat loss. The sub-cutaneous or the hypodermis layer is some times not considered as part of the skin tissue.
Correction of tissue defects including functional, cosmetic, and aesthetic defects have primarily focused on injecting or implanting non-biological materials such as saline and silicone or processed biological materials such as isolated and cultured fibroblasts or other tissue cells. Introducing non-biological material or biological material derived from another source, for example, bovine collagen or cultured fibroblasts, may result in adverse reactions in the individual.
Therefore, there exists a need for simpler and practical procedures to repair tissue defects, including skin defects and for a device to process the tissue to enable repairing the defective tissue. The present disclosure provides methods to process a suitable tissue using a tissue grinder and to reintroduce the processed tissue to correct or repair the defective tissue site.
The According to the present disclosure, a tissue grinder is used to process a suitable tissue from a suitable source from a patient such that the processed tissue is amenable for immediate reintroduction to a defective site on the patient for repairing the defect. A suitable tissue is for example, a skin tissue and a suitable source, for example, is an abdominal area of the patient in which the procedure is to be performed.
The method of repairing a defective tissue site includes the steps of obtaining a skin and subcutaneous tissue from a suitable source, removing a top epithelial component from the skin and the subcutaneous tissue and grinding the skin and subcutaneous tissue into constituents in a tissue grinder to provide a ground tissue, the tissue grinder comprising a cutting surface. The method also includes reintroducing the ground tissue to the defective site by directly applying the ground tissue at the defective site to repair the defective site.
The method incorporates the use of a surgical hand-held tissue grinder. The tissue grinder is used for grinding skin and subcutaneous tissue and includes a sterile polymer housing having a first opening adapted to receive the skin and subcutaneous tissue and a second opening in fluid connection with the first opening. The tissue grinder also includes a sterile grinder disposed within the housing. The grinder includes a grinding element provided with a plurality of cutting surfaces adapted to operably engage with the housing to provide ground tissue and further includes a handle mechanism coupled to the grinding element to move the grinding element with respect to the housing to grind the skin and subcutaneous tissue, wherein the ground tissue is deposited in a syringe for reintroduction into the patient.
The grinder assembly comprises a housing formed to include an inlet adapted to receive a material to be ground. The grinder assembly also includes a grinder having a cylindrical grinding element disposed within the housing, the grinding element formed to include a plurality of cutting surfaces adapted to grind the material. The grinder assembly includes a blade associated with the grinding element and configured to engage the grinding element to further cut the material ground by the grinding element. A handle mechanism is coupled to the grinding element to move the grinding element with respect to the housing and blade.
Additional features of the disclosure will become apparent to those skilled in the art upon consideration of the following detailed description of illustrative embodiments exemplifying the best mode of carrying out the disclosure as presently perceived.
The present invention and the advantages thereof will become more apparent upon consideration of the following detailed description when taken in conjunction with the accompanying drawings of which:
While the present disclosure may be susceptible to embodiment in different forms, there is shown in the drawings, and herein will be described in detail, embodiments with the understanding that the present description is to be considered an exemplification of the principles of the disclosure and is not intended to limit the disclosure to the details of construction and the arrangements of components set forth in the following description or illustrated in the drawings.
The disposable, surgical hand-held tissue grinder 10 is adapted for grinding skin and subcutaneous tissue for use in repairing tissue defects. The tissue grinder 10, as is shown in
The housing 12 of hand-held tissue grinder 10 is dimensioned to be easily gripped by the hand of a medical practitioner to make it easy to operate the tissue grinder 10 during the medical procedure. Housing 12 is sterilized and is ready to be used by the medical practitioner from the packaging and can be discarded after the procedure is completed. Feed basket 16 is adapted to contain excised tissue prior to grinding. In order to force the tissue onto grinding element 24 of grinder 20, a compression arm 26 is used. Compression arm 26 is preferably hingedly coupled to handle 28 of housing 12. Housing 12 is preferably made from a polymer material so that it can be disposed of after use. Housing 12, shown in the illustrative embodiment of
Sterile grinding element 24 is configured to be disposed substantially within housing 12, as shown in
Grinding element 24 includes a first end 36 and a spaced apart second end 38, as shown in
Cut tissue that passes through openings 30 is cut a second time by blade 42 of injection tube 44 of syringe 22, as shown, in
Syringe 22 is configured to be positioned within grinder 20, as shown in
Cylindrical wall 52 also includes detents 62, 64 that allow two position syringe sleeve 46 to be locked from a first position where slot 66 is aligned with slot 54 of injection tube 44 so that blade 42 can extend through slot 66 to a second position where slot 66 is not aligned with injection tube 44 and covers blade 42. In the second position, plunger 48 can be moved through injection tube 44 to compress the ground tissue so that it exits needle 50. Syringe sleeve 46 includes collar 47 to allow a user to rotate syringe sleeve 46 with respect to injection tube 44 from the first position to the second position. Syringe sleeve 46 is designed to protect the user from blade 42 and to seal opening 54 so that ground tissue can be ejected from needle 50.
Plunger 48 is adapted to fit within injection tube 44. Plunger 48 includes shaft 68 that allows plunger 48 to be pushed within injection tube 44. In use, the user removes a sterilized hand-held tissue grinder 10 from a sealed bag or container. With the hand-held tissue grinder 10 fully assembled, the user excises tissue from the patient and inserts the tissue in the feed basket 14. Once tissue is in feed basket 14 handle 26 is squeezed to force tissue onto grinder element 24. With tissue positioned against grinder element 24, handle 40 is rotates to cause cutting surfaces 34 to cut tissue.
While handle 40 and cutting element 24 rotate within housing 12, syringe 22 does not rotate, which allows blade 42 to engage inside surface of cutting element 24 to cut tissue for a second time and direct tissue into injection tube 44. Once a sufficient amount of tissue is ground to repair a defect in a patient and deposited inside of injection tube 44, syringe 22 is removed from housing 12. Once removed from housing 12, syringe sleeve 46 is rotated from the first position to a second position to cover blade 42 and opening 54. Once opening 54 is covered, needle 50 is installed on injection tube 44 and plunger 48 is pressed inwardly to eject ground tissue from needle 50.
In an embodiment, a suitable tissue such as, for example, a skin and subcutaneous tissue is obtained from a suitable source of the individual with a tissue defect. As used herein, “skin and subcutaneous tissue” generally refers to the skin tissue comprising the epidermis, the dermis and the hypodermis or the layer beneath the dermis layer. In addition, the term “skin tissue” generally refers to the epidermal and the dermal layers. For example, a suitable source to obtain the skin and subcutaneous tissue is lower abdominal area. Other suitable sources include thigh, buttocks, and any bodily region capable of providing an adequate amount of the skin and subcutaneous tissue.
Any tissue that can be ground and reintroduced to repair a tissue defect or augment the structural or functional integrity of a tissue is within the scope of this disclosure.
The skin and subcutaneous tissue is removed from the suitable source by employing any suitable technique that is practiced in the art. For example, the skin and subcutaneous tissue is obtained from the abdominal region by surgically excising the desired tissue from the source. The nature and the amount of the tissue depends on the nature of the defect and the extent of the defect to be repaired and the availability of suitable tissue at the source. For example, a tissue defect includes a facial defect. The tissue defect can be functional, cosmetic or a combination thereof. Some examples of tissue defects includes, for example wrinkles, altering of facial contours and scar correction. It is preferable to obtain the tissue from the same individual for whom the tissue defect is corrected.
In an embodiment, after the tissue is obtained from the suitable source, the skin tissue is processed by removing an epithelial component or the epidermal layer of the skin tissue. Epithelial components include, such as, for example, keratinocytes, dendritic cells, melanocytes, hair follicles and squamous cell. It is preferable to substantially remove the hair follicles and other undesirable constituents prior to reintroduction of the ground tissue to the defective tissue site. The epithelial component is removed using any standard methods available in the art. For example, an epithelial component is removed by mechanical force, Other modes of removal, such as, for example, chemical and biological treatments can also be used to remove or substantially reduce the prevalence of an epithelial component in the harvested skin and subcutaneous tissue.
After an appropriate amount of the skin and subcutaneous tissue has been processed, the processed tissue is subject to a grinding force in a tissue grinder. In an embodiment, the grinding force is a torque applied by a grinding element of the grinder. In an embodiment, the grinding element includes cutting surface that has a plurality of openings. Other forms of mechanical action, in addition to the rotational torque is suitable. For example, horizontal sliding movement of the grinding element is also suitable for operating the tissue grinder to provide a ground tissue. Briefly, the harvested tissue is transferred to the tissue grinder through an opening in the housing of the grinder. Optionally, the tissue is held against the grinding element by force such that the grinding element engagedly contacts the tissue. The grinding element is operated such that the movement of the grinding element with respect to the housing grinds the tissue. The ground tissue is collected and transferred to another suitable device, e.g., a syringe to be introduced into the defective tissue site.
In an embodiment the skin and subcutaneous tissue is ground by the grinder such that the ground tissue has constituents that range in size from about 50 .mu.m to about 5000 .mu.m in diameter. The constituents can also range in size from about 100 .mu.m to about 1000 .mu.m; and from about 500 .mu.m to about 3000 .mu.m. The ground tissue includes skin constituents that range in size that are slightly bigger than the size of an individual cell to about 10-100 times bigger than the size of the individual cell. The ground skin and subcutaneous tissue contains aggregates of cells that are capable of providing support for growth and establishment of the implanted tissue and correct the tissue defect. For example, fat cells and blood vessels that form a part of the dermal layer and the subcutaneous layer provide nourishment to support the growth of the skin tissue fat immediately surrounds the implanted tissue.
After the tissue is ground, optionally the tissue is transferred to a suitable applicator device, such as, for example, a syringe. The ground tissue is then directly administered at a defective site. In an embodiment, the ground tissue is injected or applied beneath the existing skin and subcutaneous tissue to correct the defect. The ground tissue can be applied under or over any layer as long as the implanted ground tissue (graft) is accepted by the surrounding tissue (host). The ground tissue can also be applied directly on a defective site with any suitable applicator. An incision can be made at the defective site to permit effective implantation of the ground tissue. After the implantation, appropriate surgical measures, such as, suturing and bandaging the defective site, are adopted as necessary.
In another embodiment, the tissue grinder is adapted to functionally engage the applicator device so that the tissue removal and transfer step is eliminated. In yet another embodiment, the tissue grinder itself comprises an applicator member capable of transferring the ground tissue to the defective site.
In another embodiment, the tissue grinder 90 is arranged to grind tissue and has a draw port 100 for connection of a syringe 120, as shown in
Tissue grinder 90 includes a top housing 103, a mill shroud 104, an upper stand 105 and a lower stand 106, as shown in
Crank 124 includes crank rod 112 and crank handle 111. Crank 124 rotates spur gear 108, which in turn rotates face gear plate 109 and perforated plate 113. Tissue received in tissue receiving chamber 126 is pressed against downwardly with plunger 101 that includes plunger cap 102. Plunger 101 pushes tissue through the holes of perforated plate 113. Tissue that extends through the holes of perforated plate 113 are cut or ground by the rotating blades of blade member 114. Ground tissue drops into internal compartment 94 of upper stand 105. Ground tissue stored in the internal compartment 94 can be drawn from the compartment through draw port 100, through hose 92 and syringe 120. A valve member 128 is positioned between syringe 120 and hose 92 to control the flow of ground tissue from the compartment 94. Valve member 128 can also be positioned between hose 92 and tissue grinder 90. Tissue grinder 90 can be designed to be dissembled for cleaning or can be constructed to be a one time use grinder.
The lower stand 106 is positioned below the upper stand 105 and flairs out as it extends away from the upper stand 105. Lower stand 106 includes a flange 130 that is configured to provide a stable base for the grinder. The top housing 103 is generally spherical in shape to provide an ergonomic surface for the user's hand.
While embodiments have been illustrated and described in the drawings and foregoing description, such illustrations and descriptions are considered to be exemplary and not restrictive in character, it being understood that only illustrative embodiments have been shown and described and that all changes and modifications that come within the spirit of the disclosure are desired to be protected. The description and figures are intended as illustrations of embodiments of the disclosure, and are not intended to be construed as having or implying limitation of the disclosure to those embodiments.
There are a plurality of advantages of the present disclosure arising from various features set forth in the description. It will be noted that alternative embodiments of the disclosure may not include all of the features described yet still benefit from at least some of the advantages of such features. Those of ordinary skill in the art may readily devise their own implementations of the disclosure and associated methods, without undue experimentation, that incorporate one or more of the features of the disclosure and fall within the spirit and scope of the present disclosure and the appended claims.
This application is a continuation-in-part of co-pending U.S. Ser. No. 12/708,685, filed Feb. 19, 2010, which is a continuation-in-part of co-pending U.S. Ser. No. 11/531,930, filed Sep. 14, 2006 and are hereby incorporated by referenced in their entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 12708685 | Feb 2010 | US |
| Child | 14059186 | US | |
| Parent | 11531930 | Sep 2006 | US |
| Child | 12708685 | US |
