Skin grafting tool and method of making composite skin grafts therewith

Abstract

The present application relates to a kind of skin grafting tools and its method for making composite skin flap, it includes crepe sheet, the crepe sheet includes the lower layer of metal film layer and the upper layer of gauze layer stacked together, the crepe sheet is set on expander above;The crepe sheet is provided with multiple transverse folds and multiple longitudinal folds;The longitudinal fold is the fold of whole crepe sheet, the transverse fold is the fold of crepe sheet being folded together with longitudinal fold.This application first makes autologous skin flap and heterogenous skin flap in turn by skin grafting tool, then autologous skin flap and heterogenous skin flap are overlapped to form composite skin flap;The skin grafting tool of the present application can carry out skin expansion transplantation at different expansion ratios;The shape of skin grafting area is regular, so that skin production is fast, uniform;Solve the problem of autologous skin source tension when large-area burn.

Description

Technical Field

[0001] This invention relates to the field of medical device technology for the clinical treatment of skin defects, and specifically to a skin grafting tool and a method for making composite skin grafts. Background Technology

[0002] Currently, the treatment of extensive deep burns remains a major challenge for clinicians. The success rate is 87.1% for burns covering 60%-69% of the total body surface area (TBSA), but only 47.8% for burns exceeding 90% TBSA. Timely wound repair is crucial for improving the success rate. If large-area deep burns cannot be closed early, subsequent treatment becomes extremely difficult; especially after skin grafting failure, the available donor sites decrease further, and local infection makes subsequent graft survival challenging. More seriously, prolonged exposure of large wounds often leads to complications such as hypermetabolic disorders, sepsis, and multiple organ dysfunction syndrome (MODS), even endangering life. Therefore, how to repair large-area deep wounds using limited donor sites while ensuring graft survival is a pressing problem in the treatment of critically ill burn patients.

[0003] Currently, there is a foldable skin graft expansion membrane on the market. This expansion membrane folds the film and pad together in both longitudinal and transverse directions into flat folds. After the skin graft is pasted onto the expansion membrane and cut, the skin graft is separated by stretching the expansion membrane in both longitudinal and transverse directions. However, this method results in poor wound drainage during skin grafting and a high rate of residual infection in the later stages of repair. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing skin grafting tools and to provide a skin grafting tool and a method for making composite skin grafts.

[0005] To achieve the above objectives, the present invention provides a skin grafting tool comprising a crepe sheet, wherein the crepe sheet comprises a lower metal film layer and an upper gauze layer stacked together, and the crepe sheet is disposed above an expander; the crepe sheet has multiple transverse folds and multiple longitudinal folds; the longitudinal folds are folds of the entire crepe sheet, and the transverse folds are folds formed by folding the crepe sheet together with the longitudinal folds.

[0006] Furthermore, the entire surface of the gauze layer or the surface in contact with the metal film layer is sprayed with adhesive, thereby forming an adhesive layer between the gauze layer and the metal film layer; multiple rows of through holes are opened at intervals in the horizontal and vertical directions on the crepe sheet.

[0007] Furthermore, the adhesive layer is composed of adhesive tapes arranged at intervals and in parallel laterally; the through holes are square through holes, and the adhesive tapes are arranged between two rows of square through holes; the fold lines of the transverse folds and longitudinal folds coincide with the center lines of each row and each column of square through holes, respectively.

[0008] Furthermore, the expander consists of two L-shaped brackets that intersect to form a square frame, and positioning posts are provided at the four corners of the expander.

[0009] Furthermore, positioning holes are provided at the four corners of the crepe sheet, and the positioning holes are fitted onto the positioning posts so that the crepe sheet is positioned in the expander.

[0010] Furthermore, each of the expanders is equipped with a handheld component on its frame.

[0011] Furthermore, the metal film layer is made of aluminum foil, and the gauze layer is made of polyamide double-pleated yarn; in the crepe sheet, the unfolded length of each horizontal pleat is the same, and the unfolded length of each vertical pleat is the same.

[0012] The present invention also provides a method for manufacturing composite leather pieces, comprising the following steps:

[0013] 1) Preparation of autologous skin grafts:

[0014] a. Based on the size of the wound, an autologous skin graft the size of a cork tray is taken using a skin harvesting machine. The dermis layer of the autologous skin graft is placed face down on the cork tray. The skin graft is cut longitudinally and transversely using a skin cutting machine. The cuts divide the autologous skin graft into N micro-autologous skin grafts. Glue is sprayed onto the surface of the autologous skin grafts attached to the cork tray. Then, the surface of the skin grafts is attached to a gauze layer.

[0015] b. Remove the cork tray;

[0016] c. Position the crepe sheet with the leather patch laid on it on the expander.

[0017] The crepe sheet comprises a lower metal film layer and an upper gauze layer stacked together, and is positioned above the expander. The crepe sheet has multiple transverse pleats and multiple longitudinal pleats. The longitudinal pleats are integral pleats of the crepe sheet, while the transverse pleats are folds formed by folding the crepe sheet together with the longitudinal pleats. The entire surface of the gauze layer, or the surface in contact with the metal film layer, is sprayed with adhesive, thus forming an adhesive layer between the gauze layer and the metal film layer. This adhesive layer consists of adhesive tapes spaced apart and arranged transversely in parallel. Multiple rows of through holes are spaced horizontally and vertically on the crepe sheet. The adhesive tapes are positioned between two rows of square through holes. The folding lines of the transverse and longitudinal pleats coincide with the center lines of each row and column of square through holes, respectively.

[0018] d. Hold both hand-held parts in the horizontal direction at the same time and stretch them in the horizontal direction to extend the crepe fabric in the horizontal direction;

[0019] e. Hold the two hand-held parts in the longitudinal direction at the same time and stretch them in the longitudinal direction to extend the crepe sheet in the longitudinal direction; remove the metal film layer to finally obtain the extended autologous micro-skin patch array, which is the autologous skin patch; and multiple rows of autologous skin through holes are formed on the autologous skin patch with horizontal and vertical intervals.

[0020] 2) Preparation of allogeneic skin grafts:

[0021] A. Based on the size of the wound, a skin graft of the same size as the cork tray is taken using a skin grafting machine. The graft is then attached to a cork tray of the same size. The skin graft is cut longitudinally and transversely using a skin cutting machine. The cuts divide the skin graft into N miniature allogeneic skin grafts. Adhesive is sprayed onto the surface of the allogeneic skin graft attached to the cork tray. Then, the surface of the allogeneic skin graft is attached to the gauze layer. Adhesive is sprayed onto the surface of the skin graft attached to the cork tray. Then, the tray is flipped over and the adhesive side is transferred to the gauze layer.

[0022] B. Remove the cork tray;

[0023] C. Position the crepe sheet with the leather patch laid on it on the expander.

[0024] The crepe sheet comprises a lower metal film layer and an upper gauze layer stacked together, and is positioned above the expander; the crepe sheet has multiple transverse pleats and multiple longitudinal pleats; the longitudinal pleats are pleats of the entire crepe sheet, and the transverse pleats are pleats formed by folding the crepe sheet together with the longitudinal pleats;

[0025] D. Hold both hand-held parts in the horizontal direction at the same time and stretch them in the horizontal direction to extend the crepe fabric in the horizontal direction;

[0026] E. Hold the two handheld parts in the longitudinal direction at the same time and stretch them in the longitudinal direction to extend the crepe sheet in the longitudinal direction; remove the metal film layer to finally obtain the extended micro-alien skin sheet array, which is the alien skin sheet;

[0027] 3) Fabrication of composite leather pieces:

[0028] i. First, lay the aforementioned foreign skin piece onto the expander through the foreign skin positioning hole;

[0029] ii. Then, the above-mentioned autologous skin grafts are laid on the expander through the autologous skin positioning holes, and the adhesive surface of the adhesive layer of the autologous skin graft is bonded to the crepe sheet of the allogeneic skin graft so that the allogeneic skin grafts and the autologous skin grafts overlap.

[0030] iii. Autologous skin grafts and allogeneic skin grafts are bonded together by the adhesive force of the adhesive layer to form a whole micro allogeneic skin graft. The micro allogeneic skin grafts fall into the autologous skin pores on the expanded autologous skin graft. Thus, the autologous skin graft and the allogeneic skin graft are stacked to form a composite skin graft.

[0031] As a preferred embodiment, the area of ​​the micro-autologous skin graft is C1×C2 square millimeters; the area of ​​the micro-allogeneic skin graft is C1×C2 square millimeters.

[0032] As a preferred embodiment, the allogeneic skin graft includes allogeneic skin grafts and xenogeneic skin grafts;

[0033] The allogeneic skin grafts are selected from allogeneic skin grafts preserved in glycerol, allogeneic skin grafts preserved in deep cryogenic freezers, allogeneic skin grafts preserved in liquid nitrogen, decellularized allogeneic skin grafts, and fresh allogeneic skin grafts.

[0034] The heterologous skin grafts are selected from acellular dermal matrix pig skin grafts, acellular dermal matrix sheep skin grafts, acellular dermal matrix frog skin grafts, and fresh pig skin grafts.

[0035] As a preferred embodiment, the allogeneic skin graft is an allogeneic skin graft preserved in glycerol, and the xenogeneic skin graft is a full-thickness acellular dermal matrix porcine skin graft.

[0036] The beneficial effects of this invention are:

[0037] The skin grafting tool of this invention can perform skin expansion and grafting at different expansion rates; the regular shape of the graft area makes skin production fast and uniform; and it solves the problem of the shortage of autologous skin sources in cases of large-area burns. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of a skin grafting tool;

[0039] Figure 2 This is a schematic diagram of the expander's structure;

[0040] Figure 3 A three-dimensional image of a crepe fabric piece;

[0041] Figure 4 for Figure 3 Enlarged view of point A;

[0042] Figure 5 for Figure 3 Enlarged view of point B;

[0043] Figure 6 This is a schematic diagram illustrating the production of a type of crepe fabric.

[0044] Figure 6 A is a diagram of the initial state of the crepe fabric; Figure 6 B is a perforation diagram of crepe fabric; Figure 6 C is a longitudinal folding diagram of the crepe fabric; Figure 6 D is a schematic diagram of the longitudinal folding of the crepe sheet; Figure 6 E is a diagram showing the horizontal folding of a crepe sheet; Figure 6 F is a diagram showing the folding and shaping of crepe fabric;

[0045] Figure 7 for Figure 6 A schematic diagram of the crepe fabric bonding layer is shown;

[0046] Figure 8 This is a schematic diagram showing the dimensions of a crepe sheet;

[0047] Figure 9 A schematic diagram illustrating the production of another type of crepe fabric;

[0048] Figure 9 A is a longitudinal folding diagram of the crepe fabric; Figure 9 B is a schematic diagram of the longitudinal folding of the crepe sheet; Figure 9 C is a diagram showing the horizontal folding of the crepe fabric; Figure 9 D is a diagram showing the folding and shaping of crepe fabric.

[0049] Figure 10 for Figure 6 and Figure 9 A schematic diagram of the Y-direction;

[0050] Figure 11 for Figure 6 and Figure 9 A schematic diagram of the X-direction;

[0051] Figure 12 A diagram illustrating the manufacturing process of leather pieces;

[0052] Figure 13 A diagram showing the expansion of the expander;

[0053] Figure 14 A top view of an autologous skin graft;

[0054] Figure 15 A top view of an autologous skin graft;

[0055] Figure 16 A schematic diagram of a foreign skin graft;

[0056] Figure 17 This is a schematic diagram illustrating the fabrication of composite leather pieces.

[0057] Figure 18 This is a schematic diagram of a composite leather graft;

[0058] In the diagram, the components are: 1. Crepe fabric; 1.1. Metal film layer; 1.5. Longitudinal pleats; 1.2. Gauze layer; 1.3. Adhesive layer; 1.31. Adhesive tape; 1.4. Transverse pleats; 1.5. Longitudinal pleats; 1.6. Through hole; 1.7. Positioning hole; 1.8. Fold line; 2. Expander; 2.1. L-shaped bracket; 2.2. Positioning post; 2.3. Handheld part; 3. Cork disc; 4. Autologous leather piece; 4. Cut seam; 4.1. Miniature autologous leather piece; 4.2. Autologous leather piece; 5. Autologous leather positioning hole; 5.1. Autologous leather square hole; 5.2. Allogeneic leather piece; 6. Miniature allogeneic leather piece; 6.1. Allogeneic leather piece; 7. Allogeneic leather positioning hole; 7.1. Composite leather piece; 8. Detailed Implementation

[0059] The present invention will now be described in further detail with reference to specific embodiments, so that those skilled in the art can understand it.

[0060] Example 1

[0061] like Figures 1-7 The skin grafting tool shown in 10 and 11 includes a crepe sheet 1, which includes a lower metal film layer 1.1 and an upper gauze layer 1.2 stacked together. The metal film layer 1.1 is made of aluminum foil, and the gauze layer 1.2 is made of polyamide double pleated yarn.

[0062] The crepe sheet 1 is positioned above the expander 2; the expander 2 is formed by two L-shaped brackets 2.1 intersecting to form a square frame, and positioning posts 2.2 are provided at the four corners of the expander 2; handheld parts 2.3 are provided on the frame of the expander 2.

[0063] The crepe piece 1 has multiple horizontal pleats 1.4 and multiple vertical pleats 1.5; the vertical pleats 1.5 are pleats of the entire crepe piece 1, and the horizontal pleats are pleats formed by folding the crepe piece 2 together with the vertical pleats 1.5. The unfolded length of each horizontal pleat is the same, and the unfolded length of each vertical pleat is the same.

[0064] An adhesive layer 1.3 is laid between the gauze layer 1.2 and the metal film layer 1.1; the adhesive layer 1.3 is composed of adhesive tapes 1.31 arranged at intervals and in parallel laterally; the through holes are square through holes 1.6, and the adhesive tapes 1.31 are arranged between two rows of square through holes 1.6.

[0065] Positioning holes 1.7 are provided at the four corners of the crepe sheet 1. The positioning holes 1.7 are fitted onto the positioning posts 2.2 so that the crepe sheet 1 is positioned on the expander 2. In the initial state of the expander 5, the distance between the positioning posts 2.2 is L1×L1, which corresponds exactly to the four positioning holes 2.3 of the folded skin graft crepe sheet (the center distance of the positioning holes 1.7 is L1×L1, as shown in the figure). Figure 8 (As shown)

[0066] The aforementioned skin grafting tools also require a cork tray 3 during the skin grafting process. This cork tray 3 is an existing product and can be purchased from the market.

[0067] In this embodiment, the cork disk is an L×L shaped object (e.g., ...). Figure 12 As shown, it is a square disk of size L×L.

[0068] like Figures 12-15 Method for performing autologous skin grafts using the above-mentioned skin grafting tools:

[0069] a. During the skin grafting process, according to the size of the wound, the appropriate amount of autologous skin graft 4 is taken by the skin harvesting machine. The dermis layer of the autologous skin graft 4 is placed face down on the cork tray 3. The skin graft 4 is cut longitudinally and transversely with the skin cutting machine. The cuts divide the autologous skin graft 4 into N micro autologous skin grafts 4.1 (the area of ​​each micro autologous skin graft 4.1 is C1×C2 square millimeters). The epidermal surface of the autologous skin graft 4 attached to the cork tray 3 is sprayed with adhesive. Then the epidermal surface of the skin graft is attached to the gauze layer 1.2.

[0070] b. Remove the cork tray 3;

[0071] c. Position the crepe sheet 1 with the leather patch laid on it on the expander 2 (the positioning holes 1.7 on the four corners of the crepe sheet are respectively fitted onto the positioning posts 2.2 on the four corners of the expander).

[0072] d. Hold both hand-held parts 2.3 in the horizontal direction at the same time and stretch them in the horizontal direction to extend the crepe fabric in the horizontal direction;

[0073] e. Grasp both handheld components 2.3 in the longitudinal direction simultaneously and stretch them longitudinally to extend the crepe sheet 1; remove the metal film layer 1.1 to obtain the expanded autologous micro-skin patch array, which is the autologous skin patch 5; and form multiple rows of autologous skin through holes 5.2 with horizontal and vertical spacing on the autologous skin patch 5 (as shown in the image). Figure 14 (as shown);

[0074] like Figure 14 As shown, the expanded micro-skin graft array has horizontal and vertical folds with unfolded lengths of S1 and S2, respectively. 1.3 represents square holes arranged alternately along the horizontal and vertical directions. After unfolding, the area corresponding to one micro-skin graft is (C1+S1)×(C1+S2) square millimeters, which is equivalent to expanding the skin graft area by (C1+S1)×(C1+S2) / C1×C1 times. C1, S1, and S2 can be selected according to actual clinical needs.

[0075] like Figure 15 As shown: Adhesive tape 1.31 is laid longitudinally along the spaced square through holes 1.6 on its back side.

[0076] Example 2

[0077] like Figures 1-7 The skin grafting tool shown in 9 to 11 includes a crepe sheet 1, which includes a lower metal film layer 1.1 and an upper gauze layer 1.2 stacked together. The metal film layer 1.1 is made of aluminum foil, and the gauze layer 1.2 is made of polyamide double pleated yarn.

[0078] The crepe sheet 1 is positioned above the expander 2; the expander 2 is formed by two L-shaped brackets 2.1 intersecting to form a square frame, and positioning posts 2.2 are provided at the four corners of the expander 2; handheld parts 2.3 are provided on the frame of the expander 2.

[0079] The crepe sheet 1 has multiple horizontal pleats 1.4 and multiple vertical pleats 1.5; the vertical pleats 1.5 are pleats of the entire crepe sheet 1, and the horizontal pleats are pleats formed by folding the crepe sheet 2 together with the vertical pleats 1.5. The unfolded length of each horizontal pleat is the same, and the unfolded length of each vertical pleat is the same.

[0080] Positioning holes 1.7 are provided on the four corners of the crepe sheet 1. The positioning holes 1.7 are fitted onto the positioning posts 2.2 so that the crepe sheet 1 is placed on the expander 2. In the initial state of the expander 5, the distance between the positioning posts 2.2 is L1×L1, which corresponds exactly to the four positioning holes 2.3 of the folded skin graft crepe sheet.

[0081] The method for preparing allogeneic skin grafts using the above-mentioned skin grafting tools is basically the same as that in Example 1:

[0082] A. Based on the size of the wound, a skin graft 6 of the same size as the cork tray is taken using a skin grafting machine. The graft is then attached to a cork tray 3 of the same size. The skin graft is cut longitudinally and transversely using a skin cutting machine. The cuts divide the skin graft into N miniature allogeneic skin grafts 6.1. Adhesive is sprayed onto the surface of the allogeneic skin graft 6 attached to the cork tray 3. Then, the surface of the allogeneic skin graft 6 is attached to the gauze layer 1.2. Adhesive is sprayed onto the surface of the skin graft 4 attached to the cork tray. Then, the skin graft is flipped over and the adhesive side is transferred to the gauze layer 1.2.

[0083] B. Remove the cork tray 3;

[0084] C. Position the crepe sheet 1, with the leather piece already laid on it, on the expander 2.

[0085] D. Hold both hand-held parts 2.3 in the horizontal direction at the same time and stretch them in the horizontal direction to extend the crepe piece 1 in the horizontal direction;

[0086] E. Grasp both handheld parts 2.3 in the longitudinal direction simultaneously and stretch them in the longitudinal direction to extend the crepe sheet 1 in the longitudinal direction; remove the metal film layer 1.1 to finally obtain the expanded micro-alien skin sheet array, which is the alien skin sheet 7. Figure 16 ).

[0087] like Figure 16 As shown: After being cut and expanded, the foreign skin piece 6 is evenly distributed on the gauze layer 1.2 to form a foreign skin piece 7 (such as a miniature skin piece 7), with a positioning hole 7.1 at each of its four corners.

[0088] The aforementioned allogeneic skin grafts 6 include allogeneic skin grafts and xenogeneic skin grafts; allogeneic skin grafts are selected from allogeneic skin grafts preserved in glycerol, allogeneic skin grafts preserved in cryogenic freezers, allogeneic skin grafts preserved in liquid nitrogen, decellularized allogeneic skin grafts, or fresh allogeneic skin grafts; xenogeneic skin grafts are selected from decellularized dermal matrix pig skin grafts, decellularized dermal matrix sheep skin grafts, decellularized dermal matrix frog skin grafts, and fresh pig skin grafts.

[0089] Example 3

[0090] like Figure 16 The method for producing composite leather pieces, as shown, includes the following steps:

[0091] i. First, lay the above-mentioned foreign skin piece 7 onto the expander 2 through the foreign skin positioning hole 7.1;

[0092] ii. Then, the above-mentioned autologous skin piece 5 is laid on the expander 2 through the autologous skin positioning hole 5.1, and the adhesive surface of the adhesive layer of the autologous skin piece 5 is bonded to the crepe piece 2 of the foreign skin piece 7 so that the foreign skin piece 7 and the autologous skin piece 5 overlap.

[0093] iii. The autologous skin graft 5 and the allogeneic skin graft 7 are bonded together by the adhesive force of the adhesive layer to form an integral micro allogeneic skin graft 7.1. The micro allogeneic skin graft 7.1 falls into the autologous skin through-hole 5.2 on the expanded autologous skin graft 5; thus, the autologous skin graft 5 and the allogeneic skin graft 7 are superimposed to form a composite skin graft 8.

[0094] like Figure 17 The composite skin graft 8 shown can be transplanted to the skin defect.

[0095] All other parts not described in detail are existing technologies. Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A skin grafting tool comprising a crepe sheet (1) comprising a lower layer of a metal film layer (1.1) and an upper layer of a gauze layer (1.2) laminated together, characterized in that: The crepe sheet (1) is arranged above the expander (2); the crepe sheet (1) is provided with a plurality of transverse folds (1.4) and a plurality of longitudinal folds (1.5); the longitudinal folds (1.5) are folds of the whole crepe sheet (1), and the transverse folds are folds of folding the crepe sheet (1) together with the longitudinal folds (1.5); the gauze layer (1.2) is entirely or in contact with the metal film layer (1.1) sprayed with adhesive glue, so as to form an adhesive layer (1.3) between the gauze layer (1.2) and the metal film layer (1.1); a plurality of rows of through holes (1.6) are arranged on the crepe sheet (1) at intervals in the transverse and longitudinal directions; the adhesive layer (1.3) is composed of adhesive tapes (1.31) arranged at intervals and in transverse parallel; the through holes (1.6) are square through holes, and the adhesive tapes (1.31) are arranged between two rows of square through holes (1.6); the folding lines (1.8) of the transverse folds (1.4) and the longitudinal folds (1.5) respectively coincide with the center lines of each row of square through holes (1.6) and each column of square through holes (1.6).

2. The skin grafting tool of claim 1, wherein: The expander (2) is formed into a square frame by two L-shaped supports (2.1) crossing each other, and the expander (2) is provided with positioning columns (2.2) on four corners.

3. The skin grafting tool of claim 2, wherein: Positioning holes (1.7) are arranged on four corners of the crepe sheet (1), and the positioning holes (1.7) are sleeved on the positioning columns (2.2) so as to arrange the crepe sheet (1) on the expander (2).

4. The skin grafting tool of claim 1, wherein: Hand-held parts (2.3) are arranged on the frames of the expander (2).

5. The skin grafting tool of claim 1, wherein: The metal film layer (1.1) is an aluminum foil layer, and the gauze layer (1.2) is a polyamide double-pleated yarn; in the crepe sheet (1), the unfolded lengths of each transverse fold (1.4) are the same, and the unfolded lengths of each longitudinal fold (1.5) are the same.

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