A composite rotator cuff patch and method of making the same
By combining warp-knitted mesh fabric with natural protein solution, a multi-layer composite shoulder and sleeve patch was prepared, which solved the problems of poor mechanical properties and biocompatibility of existing shoulder and sleeve patches and achieved good mechanical support and tissue regeneration effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- ZHEJIANG XINGYUE BIOTECH
- Filing Date
- 2023-08-28
- Publication Date
- 2026-06-05
Smart Images
Figure CN116899015B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of biomaterials technology, and in particular to a composite material rotator cuff patch and its preparation method. Background Technology
[0002] Rotator cuff injury is one of the most common diseases of the shoulder joint. Its main symptoms are shoulder pain and limited shoulder joint movement. It is mainly caused by traumatic factors such as sports and degenerative factors due to aging.
[0003] Rotator cuff tears are primarily treated through direct surgical suturing, autologous transplantation, allogeneic transplantation, or implantation of prosthetic materials. Post-operative stress on the sutures and the healing of the tendon-bone interface are key medical challenges.
[0004] Currently, rotator cuff patches include collagen patches, decellularized matrix patches, three-dimensional parallel collagen fiber-silk scaffold patches, electrospun patches, woven patches, and three-dimensional patches. Collagen materials can provide space for cell adhesion, but their clinical application is limited due to their poor mechanical properties and short degradation time. Decellularized matrix patches pose a risk of viral infection and generally lack suitable porous structures, making it difficult to control their mechanical properties. Woven patches, especially polymer-woven patches, have high and stable mechanical properties, but their biocompatibility is not as good as natural biomaterials (such as collagen), and they generally form scars rather than tissue regeneration in vivo.
[0005] Current research in tissue engineering combines mesh materials with natural biomaterials to construct bio-scaffolds that promote tendon / ligament repair, overcoming the limitations of traditional patches in clinical applications. Patent 201510005188.3 provides a three-dimensional parallel collagen fiber-silk scaffold, and patent 201510716278.3 provides a three-dimensional composite material for tendon and ligament repair. Both methods involve stacking different materials; however, the composite scaffolds prepared by this method exhibit weak bonding between different material layers and are prone to separation. Patent 201510113943.X provides a collagen / silk fibroin composite scaffold using a single layer of silk fibroin nonwoven fabric for mechanical support, but its mechanical properties are inferior to woven mesh patches. Currently, the fabrication methods for mesh-material composite natural biomaterial patches are generally single-layer mesh composites, which cannot provide sufficient mechanical support and degradation time in the event of large rotator cuff tears. Based on the shortcomings of the above preparation methods, there is an urgent need to provide a new preparation method to prepare composite shoulder and cuff patches with good mechanical properties and biocompatibility, stable structure, and satisfactory degradation performance. Summary of the Invention
[0006] The purpose of this invention is to provide a composite material rotator cuff patch and its preparation method to solve the problems of poor mechanical properties and biocompatibility of rotator cuff patches in the prior art.
[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution:
[0008] This invention provides a method for preparing a composite material shoulder and cuff patch, comprising the following steps:
[0009] 1) The fabric is sequentially immersed and freeze-dried to obtain a single-layer mesh composite;
[0010] 2) The single-layer mesh composite was sequentially rehydrated, stacked, immersed, and freeze-dried to obtain a multi-layer stacked composite;
[0011] 3) By sequentially cross-linking and sterilizing the multilayer composite material, a composite shoulder and sleeve patch can be obtained;
[0012] The fabric has a warp-knitted mesh structure;
[0013] In steps 1) and 2), the immersion treatment is carried out in a protein solution.
[0014] Preferably, the fabric is composed of polylactic acid, silk fibroin, polyethylene or polypropylene; the mesh size of the fabric is 0.2-2 mm, and the thickness of the single-layer mesh composite is 0.2-3 mm.
[0015] Preferably, the protein solution is a collagen solution or a silk fibroin solution; the concentration of the collagen solution is 5–25 mg / mL; and the concentration of the silk fibroin solution is 1–10 wt%.
[0016] Preferably, in step 2), the number of stacked layers is 2 to 6.
[0017] Preferably, in step 3), the crosslinking treatment includes crosslinking agent crosslinking treatment or thermal crosslinking treatment; the crosslinking agent used in the crosslinking agent crosslinking treatment includes carbodiimide, ethanol or glutaraldehyde.
[0018] Preferably, after the crosslinking agent crosslinks the composite material, the multilayer composite material is sequentially immersed in water for injection and then freeze-dried.
[0019] Preferably, the freeze-drying process involves sequentially cooling at -40 to 5°C for 2 to 6 hours, pre-cooling at -40 to -15°C for 1 to 3 hours, and vacuum drying at -20 to 5°C for 20 to 100 hours.
[0020] Preferably, in step 3), the sterilization process includes microwave sterilization, ultraviolet sterilization, electron beam radiation sterilization, X-ray radiation sterilization, or gamma-ray radiation sterilization.
[0021] The present invention provides a composite material shoulder and sleeve patch prepared by the aforementioned preparation method, wherein the thickness of the composite material shoulder and sleeve patch is 0.5 to 8 mm.
[0022] Preferably, the composite material shoulder and sleeve patch is cut in the middle of the thickness direction to 1 / 3 to 1 / 2 of its length to form a herringbone patch.
[0023] Compared with the prior art, the beneficial effects of the present invention are mainly reflected in:
[0024] (1) The composite material rotator cuff patch of the present invention is made of warp-knitted fabric and natural protein porous sponge scaffold, and has good mechanical properties and biocompatibility. It can provide sufficient mechanical support in the early stage of implantation, while promoting tissue regeneration, repairing damaged tendons, and reducing the re-tear rate.
[0025] (2) The composite material rotator cuff patch prepared by the present invention can be cut arbitrarily. In clinical applications, it can be used as a single layer to cover the injured tendon, or it can be cut into a "V" shape in the thickness direction to wrap the tendon stump. The method of use is flexible.
[0026] (3) The composite material rotator cuff patch prepared by the present invention has a tendon rupture strength greater than 400N, good mechanical properties, and is suitable for tendon injury repair. Attached Figure Description
[0027] Figure 1 This is a schematic diagram of the composite material shoulder and sleeve patch prepared in Example 2;
[0028] Figure 2 This is a schematic diagram of the composite material shoulder and sleeve patch prepared in Example 1 cut into a herringbone shape.
[0029] Figure 3 This is an external view of the composite shoulder and sleeve patch prepared in Example 1;
[0030] Figure 4 Scanning electron microscope image of the composite shoulder and cuff patch prepared in Example 2:
[0031] Figure 5 Figures showing the establishment of an animal model and the implantation of the composite rotator cuff patch prepared in Example 2;
[0032] Figure 6 This is a diagram showing the composite rotator cuff patch of Example 2, 6 weeks after implantation, being enveloped by newly formed tissue.
[0033] Figure 7This is a diagram of the canine tendon rupture strength test 6 weeks after implantation of the composite material rotator cuff patch in Example 2. Detailed Implementation
[0034] This invention provides a method for preparing a composite material shoulder and cuff patch, comprising the following steps:
[0035] 1) The fabric is sequentially immersed and freeze-dried to obtain a single-layer mesh composite;
[0036] 2) The single-layer mesh composite was sequentially rehydrated, stacked, immersed, and freeze-dried to obtain a multi-layer stacked composite;
[0037] 3) By sequentially cross-linking and sterilizing the multilayer composite material, a composite shoulder and sleeve patch can be obtained;
[0038] The fabric has a warp-knitted mesh structure;
[0039] In steps 1) and 2), the immersion treatment is carried out in a protein solution.
[0040] In this invention, the fabric is composed of polylactic acid, silk fibroin, polyethylene or polypropylene, preferably polylactic acid, silk fibroin or polypropylene, and more preferably polylactic acid; the mesh size of the fabric is 0.2-2 mm, preferably 0.4-1.8 mm, and more preferably 0.5-1.5 mm; the thickness of the single-layer mesh composite is 0.2-3 mm, preferably 0.5-2.5 mm, and more preferably 1.0-2.0 mm.
[0041] In this invention, the protein solution is a collagen solution or a silk fibroin solution, preferably a collagen solution; the concentration of the collagen solution is 5-25 mg / mL, preferably 8-22 mg / mL, and more preferably 10-20 mg / mL; the concentration of the silk fibroin solution is 1-10 wt%, preferably 3-8 wt%, and more preferably 4-6 wt%.
[0042] In this invention, in step 2), the number of stacked layers is 2 to 6, preferably 3 to 5, and more preferably 3 or 4.
[0043] In this invention, during step 2), the warp and weft directions of each single-layer mesh composite can be the same or rotated by a certain angle when stacking. When stacking 2 layers, it is preferable to rotate the two single-layer mesh composites 90 degrees clockwise and stack them in sequence. When stacking 4 layers, it is preferable to rotate each layer 45 degrees clockwise and stack them in sequence. When stacking 6 layers, it is preferable to rotate each layer 30 degrees clockwise and stack them in sequence.
[0044] In this invention, in step 3), the crosslinking treatment includes crosslinking agent crosslinking treatment or thermal crosslinking treatment, preferably thermal crosslinking treatment; the crosslinking agent used in the crosslinking agent crosslinking treatment includes carbodiimide (EDAC), ethanol or glutaraldehyde, preferably carbodiimide or glutaraldehyde, and more preferably glutaraldehyde; the thermal crosslinking treatment includes vacuum thermal crosslinking treatment or wet heat crosslinking treatment.
[0045] In this invention, the freeze-drying process steps are as follows: sequentially cooling at -40 to 5°C for 2 to 6 hours, preferably at -30 to 5°C for 3 to 5 hours, and more preferably at -20 to 5°C for 3 hours; pre-cooling at -40 to -15°C for 1 to 3 hours, preferably at -35 to -18°C for 1.5 to 2.5 hours, and more preferably at -30 to -20°C for 2 hours; and vacuum drying at -20 to 5°C for 20 to 100 hours, preferably at -15 to 3°C for 30 to 90 hours, and more preferably at -10 to 0°C for 40 to 80 hours.
[0046] In this invention, the vacuum degree during vacuum drying is <10 Pa, preferably 3 to 8 Pa, and more preferably 4 to 7 Pa.
[0047] In this invention, the sterilization process in step 3) includes microwave sterilization, ultraviolet sterilization, electron beam radiation sterilization, X-ray radiation sterilization or gamma-ray radiation sterilization, preferably electron beam radiation sterilization, X-ray radiation sterilization or gamma-ray radiation sterilization, and more preferably electron beam radiation sterilization or gamma-ray radiation sterilization.
[0048] The present invention also provides a composite material shoulder and sleeve patch prepared by the above preparation method, wherein the thickness of the composite material shoulder and sleeve patch is 0.5-8 mm, preferably 1-7 mm, and more preferably 2-6 mm.
[0049] In this invention, the composite material shoulder and sleeve patch is cut in the middle of the thickness direction to 1 / 3 to 1 / 2 of its length to form a herringbone patch.
[0050] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0051] Example 1
[0052] A 3wt% silk fibroin solution was kept at 4°C for 30 minutes. A polylactic acid warp-knitted fabric with a mesh size of 0.75 mm was moistened and stretched flat. The polylactic acid warp-knitted fabric was then immersed in the silk fibroin solution. When the silk fibroin solution seeped out from the mesh to completely cover the fabric surface and the seepage thickness reached 1 mm, the composite of the fabric and the protein solution was freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at -20°C for 5 hours, pre-frozen at -20°C for 2 hours in a freeze dryer, and dried at 0°C under a vacuum of 5 Pa for 24 hours in a freeze dryer to obtain a single-layer mesh composite with a thickness of 2 mm.
[0053] Four monolayer mesh composites were prepared according to the above method. The four monolayer mesh composites were rehydrated, and then the four monolayer mesh composites were stacked one by one, rotated 45 degrees clockwise. The stacked composites were then immersed in a 3wt% silk fibroin solution, so that the liquid level of the silk fibroin solution was equal to the thickness of the stacked composites. The stacked composites and the protein solution were freeze-dried together. The freeze-drying process was as follows: sequentially cooling at -20℃ for 5 hours, pre-freezing at -20℃ for 2 hours in a freeze dryer, and drying at 0℃ under a vacuum of 5 Pa for 48 hours in a freeze dryer to obtain a multilayer stacked composite with a thickness of 8 mm.
[0054] The multilayer composite was immersed in a 0.25 wt% glutaraldehyde solution and crosslinked at 25°C for 48 h. Afterward, it was immersed in water for injection and washed in a constant-temperature shaker at 25°C and 30 rpm for 24 h, with the water for injection changed every 12 h. The washed multilayer composite was then freeze-dried. The freeze-drying process consisted of: sequentially cooling at -20°C for 5 h, pre-freezing at -20°C for 2 h in a freeze dryer, and drying at 0°C under a vacuum of 5 Pa for 24 h in a freeze dryer. Finally, it was sterilized by gamma ray radiation with an absorbed dose of 20 kGy for 24 h to obtain the composite shoulder cuff patch.
[0055] Example 2
[0056] A collagen solution with a concentration of 20 mg / mL was kept at 4°C for 20 min. A silk fibroin warp-knitted fabric with a mesh size of 0.25 mm was moistened and stretched flat. The silk fibroin warp-knitted fabric was then immersed in the collagen solution. When the collagen solution seeped out from the mesh to completely cover the fabric surface and the seepage thickness reached 1 mm, the fabric-protein solution complex was kept at 4°C for 40 min and then freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at -20°C for 5 h, pre-frozen at -20°C for 2 h in a freeze dryer, and dried at 0°C under a vacuum of 8 Pa for 72 h in a freeze dryer to obtain a single-layer mesh complex with a thickness of 3 mm.
[0057] Two monolayer mesh composites were prepared according to the above method. The two monolayer mesh composites were rehydrated, and then the two monolayer mesh composites were stacked one after the other, rotated 90 degrees clockwise. The stacked composites were then immersed in a collagen solution with a concentration of 20 mg / mL, so that the liquid level of the collagen solution was equal to the thickness of the stacked composites. The stacked composites and the protein solution were then freeze-dried together. The freeze-drying process was as follows: sequentially cooling at -20℃ for 5 h, pre-freezing at -20℃ for 2 h in a freeze dryer, and drying at 0℃ under vacuum of 8 Pa for 96 h in a freeze dryer to obtain a multilayer stacked composite with a thickness of 6 mm.
[0058] The multilayer composite was immersed in an EDAC solution with a concentration of 10 mg / mL and crosslinked at 25°C for 8 h. Then, it was immersed in water for injection and washed in a constant temperature shaker at 15°C and 20 rpm for 72 h, with the water for injection being changed every 15 h. The washed multilayer composite was then freeze-dried. The freeze-drying process was as follows: sequentially, it was cooled at 4°C for 5 h, pre-frozen at -40°C in a freeze dryer for 3 h, and dried in a freeze dryer at a vacuum of 8 Pa and a temperature of 0°C for 24 h. Finally, it was sterilized by electron beam radiation with an absorbed dose of 22 kGy within 18 h to obtain the composite shoulder cuff patch.
[0059] The composite shoulder cuff patch prepared in this embodiment was observed by scanning electron microscopy (see...). Figure 4 The sponge layer and fabric layer of the composite shoulder and sleeve patch can be clearly identified from the cross-section.
[0060] Example 3
[0061] A collagen solution with a concentration of 10 mg / mL was kept at 4°C for 15 min. A polypropylene warp-knitted mesh fabric with a mesh size of 2 mm was moistened and stretched flat. The polypropylene warp-knitted mesh fabric was then immersed in the collagen solution. When the collagen solution seeped out from the mesh to completely cover the fabric surface and the seepage thickness reached 0.5 mm, the fabric-protein solution complex was kept at 4°C for 20 min and then freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at -20°C for 4.5 h, pre-frozen at -20°C in a freeze dryer for 2 h, and dried at 0°C under a vacuum of 6 Pa for 24 h to obtain a single-layer mesh complex with a thickness of 2 mm.
[0062] Four monolayer mesh composites were prepared according to the above method. The four monolayer mesh composites were rehydrated, and then stacked one on top of the other by rotating them clockwise by 45 degrees. The stacked composites were then immersed in a collagen solution with a concentration of 10 mg / mL, so that the liquid level of the collagen solution was equal to the thickness of the stacked composites. The stacked composites and the protein solution were then freeze-dried together. The freeze-drying process was as follows: sequentially cooling at -20℃ for 6 h, pre-freezing at -20℃ for 2 h in a freeze dryer, and drying at 0℃ under a vacuum of 6 Pa for 48 h in a freeze dryer, to obtain a multilayer stacked composite with a thickness of 8 mm.
[0063] The multilayer composite was placed in a vacuum drying oven and thermally crosslinked at a vacuum of 8 mbar and a temperature of 110°C for 72 h. Finally, it was sterilized by electron beam radiation with an absorbed dose of 22 kGy within 18 h to obtain the composite shoulder sleeve patch.
[0064] Example 4
[0065] A 5 wt% silk fibroin solution was kept at 4°C for 5 minutes. A 2 mm mesh fabric was moistened, stretched, and then immersed in the silk fibroin solution. When the silk fibroin solution seeped out of the mesh and completely covered the fabric surface with a seepage thickness of 0.5 mm, the fabric-protein solution complex was kept at 4°C for 10 minutes and then freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at -20°C for 4 hours, pre-frozen at -20°C for 2 hours in a freeze dryer, and dried at 0°C under a vacuum of 4 Pa for 24 hours in a freeze dryer to obtain a single-layer mesh complex with a thickness of 2.5 mm.
[0066] Two single-layer mesh composites were prepared according to the above method. The two single-layer mesh composites were rehydrated, and then the two single-layer mesh composites were stacked one after the other by rotating them 90 degrees clockwise. The stacked composites were then immersed in a 5 wt% silk fibroin solution, so that the liquid level of the silk fibroin solution was equal to the thickness of the stacked composites. The stacked composites and the protein solution were then freeze-dried. The freeze-drying process was as follows: sequentially cooling at 4℃ for 4 hours, pre-freezing at -40℃ in a freeze dryer for 2 hours, and drying at 0℃ under vacuum of 8 Pa for 48 hours in a freeze dryer to obtain a multilayer stacked composite with a thickness of 6 mm.
[0067] The multilayer composite was placed in a vacuum drying oven and thermally crosslinked at a vacuum of 6 mbar and a temperature of 110°C for 48 h. Finally, it was sterilized by gamma radiation with an absorbed dose of 20 kGy within 24 h to obtain the composite shoulder sleeve patch.
[0068] Example 5
[0069] A collagen solution with a concentration of 10 mg / mL was kept at 4°C for 20 min. A polylactic acid warp-knitted fabric with a mesh size of 0.45 mm was moistened and stretched flat. The polylactic acid warp-knitted fabric was then immersed in the collagen solution. When the collagen solution seeped out from the mesh to completely cover the fabric surface and the seepage thickness reached 0.5 mm, the fabric-protein solution complex was kept at 4°C for 20 min and then freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at -20°C for 5 h, pre-frozen at -40°C in a freeze dryer for 2 h, and dried at a vacuum of 7 Pa and a temperature of -10°C in a freeze dryer for 48 h to obtain a single-layer mesh complex with a thickness of 2 mm.
[0070] Three monolayer mesh composites were prepared according to the above method. The three monolayer mesh composites were rehydrated, and then the three monolayer mesh composites were stacked one by one, rotated 60 degrees clockwise. The stacked composites were then immersed in a collagen solution with a concentration of 10 mg / mL, so that the liquid level of the silk fibroin solution was equal to the thickness of the stacked composites. The stacked composites and collagen were then freeze-dried together. The freeze-drying process was as follows: sequentially, the composites were cooled at 4℃ for 5 h, pre-frozen at -40℃ in a freeze dryer for 2 h, dried at -20℃ under vacuum of 6 Pa for 24 h, and dried at -10℃ for 48 h, to obtain a multilayer stacked composite with a thickness of 6 mm.
[0071] The multilayer composite was subjected to hydrothermal crosslinking at 40℃ and 70% humidity for 72 hours, followed by freeze-drying. The freeze-drying process consisted of sequentially cooling at 4℃ for 4 hours, pre-freezing at -20℃ in a freeze dryer for 2 hours, and drying at 0℃ and 8 Pa vacuum for 24 hours in a freeze dryer. Finally, it was sterilized by electron beam radiation with an absorbed dose of 22 kGy within 24 hours to obtain the composite shoulder sleeve patch.
[0072] Comparative Example 1
[0073] A collagen solution with a concentration of 20 mg / mL was kept at 4°C for 20 min. A silk fibroin warp-knitted fabric with a mesh size of 0.25 mm was moistened and stretched flat. The silk fibroin warp-knitted fabric was then immersed in the collagen solution. When the collagen solution seeped out from the mesh to completely cover the fabric surface and the seepage thickness reached 1 mm, the fabric-protein solution complex was kept at 4°C for 40 min and then freeze-dried. The freeze-drying process was as follows: sequentially, the fabric was cooled at 4°C for 5 h, pre-frozen at -40°C in a freeze dryer for 3 h, and dried at 0°C under a vacuum of 8 Pa for 72 h to obtain a single-layer mesh complex with a thickness of 3 mm.
[0074] The monolayer mesh composite was immersed in an EDAC solution with a concentration of 10 mg / mL and crosslinked at 25 °C for 8 h. After that, it was immersed in water for injection and washed in a constant temperature shaker at 15 °C and 20 rpm for 72 h, with the water for injection being changed every 15 h. The washed monolayer mesh composite was then freeze-dried. The freeze-drying process was as follows: sequentially, it was cooled at 4 °C for 5 h, pre-frozen at -40 °C in a freeze dryer for 3 h, and dried in a freeze dryer at a vacuum of 8 Pa and a temperature of 0 °C for 24 h. Finally, it was sterilized by electron beam radiation with an absorbed dose of 22 kGy, and the sterilization was completed within 18 h to obtain the composite shoulder cuff patch.
[0075] Performance testing
[0076] (1) Tensile strength test: Five composite shoulder sleeve patches were prepared using the method of Example 2, and five shoulder sleeve patches were prepared using the method of Comparative Example 1. The tensile strength of the five composite shoulder sleeve patches prepared in Example 2 and the five shoulder sleeve patches prepared in Comparative Example 1 were tested according to GB / T 3923.1-2013 "Textiles - Tensile Properties of Fabrics - Part 1: Determination of Breaking Strength and Elongation at Break (Strip Method)". The samples were clamped on the mechanical testing equipment with the length direction parallel to the tensile direction. The results are shown in Table 1:
[0077] Table 1 Tensile strength test results
[0078]
[0079]
[0080] As can be seen from Table 1, the tensile strength of the composite shoulder and sleeve patch prepared in Example 2 is greater than 80 N / cm, which is higher than that of the shoulder and sleeve patch without stacking treatment.
[0081] (2) Tendon injury repair performance test:
[0082] a. Animal Model Establishment: The experimental animals were beagle dogs. After anesthesia, the dogs underwent routine hair removal, skin preparation, and disinfection. A midline incision was made centered on the greater tubercle of the humerus. The subcutaneous and connective tissue layers were bluntly dissected, and the biceps brachii muscle was retracted to fully expose the greater tubercle. The infraspinatus tendon was completely severed near its humeral insertion. The remaining distal end of the infraspinatus tendon was cleaned up on the greater tubercle. Two bone holes were drilled at the original infraspinatus insertion point on the greater tubercle using 1mm Kirschner wires, and the infraspinatus insertion point was reconstructed through the bone tunnel using sutures.
[0083] b. Patch implantation: The composite rotator cuff patch prepared in Example 2 was rehydrated, and the tendon and test specimen were sutured to the severed infraspinatus tendon. After rinsing the surgical incision, the subcutaneous tissue layer and skin were closed sequentially (see...). Figure 5 ).
[0084] c. Tissue repair capability:
[0085] Six weeks post-surgery, the infraspinatus tendon of the beagle was removed, and the implanted patch was completely encapsulated by new tissue (see [link to original text]). Figure 6 Fracture strength was measured, and the results are as follows: Figure 7 As shown, the repaired tendon rupture strength is greater than 400N, exhibiting good mechanical properties. The results indicate that the composite rotator cuff patch made of double-layer warp-knitted silk fibroin fabric combined with collagen is suitable for repairing tendon injuries.
[0086] As shown in the above embodiments, this invention provides a composite material rotator cuff patch and its preparation method. First, the fabric is sequentially immersed and freeze-dried to obtain a single-layer mesh composite. Then, the single-layer mesh composite is sequentially rehydrated, stacked, immersed, and freeze-dried to obtain a multi-layer composite. Finally, the multi-layer composite is sequentially cross-linked and sterilized to obtain a composite rotator cuff patch with a thickness of 0.5–8 mm. In use, it can be cut into a "V" shape in the thickness direction to wrap the tendon stump, offering flexible application. The composite material rotator cuff patch prepared by this invention possesses good mechanical properties and biocompatibility, providing sufficient mechanical support in the early stages of implantation, while also promoting tissue regeneration, repairing damaged tendons, and reducing the re-tear rate.
[0087] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a composite material shoulder and cuff patch, characterized in that, Includes the following steps: 1) The fabric is sequentially immersed and freeze-dried to obtain a single-layer mesh composite; 2) The single-layer mesh composite was sequentially rehydrated, stacked, immersed, and freeze-dried to obtain a multi-layer stacked composite; 3) By sequentially cross-linking and sterilizing the multilayer composite material, a composite shoulder and sleeve patch can be obtained; The fabric has a warp-knitted mesh structure; In steps 1) and 2), the immersion treatment is carried out in a protein solution; In step 2), each single-layer mesh composite is stacked by rotating it at a certain angle in the warp and weft directions.
2. The preparation method according to claim 1, characterized in that, The fabric is composed of polylactic acid, silk fibroin, polyethylene or polypropylene; the mesh size of the fabric is 0.2-2 mm, and the thickness of the single-layer mesh composite is 0.2-3 mm.
3. The preparation method according to claim 1 or 2, characterized in that, The protein solution is a collagen solution or a silk fibroin solution; the concentration of the collagen solution is 5–25 mg / mL; the concentration of the silk fibroin solution is 1–10 wt%.
4. The preparation method according to claim 3, characterized in that, In step 2), the number of stacked layers is 2 to 6.
5. The preparation method according to claim 1, 2, or 4, characterized in that, In step 3), the crosslinking treatment includes crosslinking agent crosslinking treatment or thermal crosslinking treatment; the crosslinking agent used in the crosslinking agent crosslinking treatment includes carbodiimide, ethanol or glutaraldehyde.
6. The preparation method according to claim 5, characterized in that, After cross-linking treatment with the cross-linking agent, the multilayer composite material undergoes sequential immersion treatment and freeze-drying, wherein the immersion treatment is carried out in water for injection.
7. The preparation method according to claim 6, characterized in that, The freeze-drying process consists of the following steps: sequentially cooling at -40 to 5°C for 2 to 6 hours, pre-cooling at -40 to -15°C for 1 to 3 hours, and vacuum drying at -20 to 5°C for 20 to 100 hours.
8. The preparation method according to claim 2, 4, or 6, characterized in that, In step 3), the sterilization process includes microwave sterilization, ultraviolet sterilization, electron beam radiation sterilization, X-ray radiation sterilization, or gamma-ray radiation sterilization.
9. The composite shoulder and sleeve patch prepared by the preparation method according to any one of claims 1 to 8, characterized in that, The thickness of the composite material shoulder and sleeve patch is 0.5–8 mm.
10. The composite material shoulder and sleeve patch according to claim 9, characterized in that, The composite material shoulder and sleeve patch is cut in the middle of the thickness direction to 1 / 3 to 1 / 2 of its length to form a "V" shaped patch.