Osteochondral scaffold

Abstract

This invention provides an osteochondral scaffold, comprising a scaffold including a flow-blocking layer and a support layer arranged sequentially from top to bottom. The flow-blocking layer is a porous matrix layer with a flat end face, and the support layer is a structural layer with an uneven end face. The support layer is formed by several base layers arranged sequentially from top to bottom, each base layer having several openings in both the transverse and longitudinal directions. The uppermost base layer is fixedly connected to the flow-blocking layer, and adjacent base layers are fixedly connected to each other. The outer peripheries of several base layers and the flow-blocking layer are fixedly connected to each other by connectors. This invention can effectively promote the differentiation of upper layer cells into chondrocytes and lower layer cells into osteocytes, improving the treatment effect of cartilage defects while effectively ensuring the stress support function of the cartilage scaffold and promoting the growth of cancellous bone.

Description

Technical Field

[0001] This invention relates to the field of cartilage repair technology, and more particularly to an osteocartilage scaffold. Background Technology

[0002] Cartilage transplantation, as a treatment option for cartilage defects, can ideally promote chondrocyte differentiation and proliferation. However, due to well-known drawbacks such as donor site morbidity, limited availability of matching donor tissue, high complication rates, and early degeneration, conventional cartilage scaffolds often have protrusions on the upper layer to increase the contact area with the cartilage layer. This makes the differentiation between the upper and lower defects of bone marrow mesenchymal stem cells unclear, resulting in newly generated cartilage that cannot effectively guarantee its strength and affecting chondrocyte migration and growth, leading to poor cartilage repair. Therefore, its use as a cartilage transplantation therapy still has certain limitations. Thus, there is an urgent need for a bone-cartilage scaffold to solve the aforementioned problems. Summary of the Invention

[0003] The purpose of this invention is to provide an osteochondral scaffold to solve the above-mentioned problems. It can effectively promote the differentiation of upper layer cells into chondrocytes and lower layer cells into osteocytes. While improving the treatment effect of cartilage defects, it can effectively ensure the stress support function of the cartilage scaffold and promote the growth of cancellous bone.

[0004] To achieve the above objectives, the present invention provides the following solution: an osteochondral scaffold, comprising a scaffold, the scaffold comprising a flow-blocking layer and a support layer arranged sequentially from top to bottom, the flow-blocking layer being a porous matrix layer with a flat end face, the support layer being a structural layer with an uneven end face, the support layer being formed by a plurality of base layers arranged sequentially from top to bottom, the base layers having a plurality of openings in both the transverse and longitudinal directions;

[0005] The uppermost base layer is fixedly connected to the flow-blocking layer, and adjacent base layers are fixedly connected to each other.

[0006] The outer periphery of several of the base layers and the flow-blocking layers are fixed to each other by connectors.

[0007] Preferably, the flow-blocking layer includes a support plate, the top end face of the support plate is flush with the top end face, the support plate is coaxially arranged with several of the base layers, and the end face area of ​​the support plate is smaller than the end face area of ​​the base layers, the end face of the base layers is composed of several conical structures.

[0008] Preferably, the support plate includes a bottom plate and a top plate. The bottom plate is fixedly connected to the base layer. The bottom plate has a plurality of through holes in the vertical direction. The through holes are arranged in a matrix on the bottom plate. The top plate is fixedly connected to the top of the bottom plate and covers the plurality of through holes.

[0009] Preferably, the support plate is an integrally formed structure, with a plurality of connecting holes at the top of the support plate and a plurality of guide holes on the side wall of the support plate, the connecting holes communicating with the guide holes.

[0010] Preferably, the cross-sections of the connecting hole and the guiding hole are both isosceles triangles.

[0011] Preferably, the base layer includes a plurality of first and second support rods spaced apart along the horizontal and vertical directions, the first and second support rods being staggered, and the first and second support rods cooperating to form a plurality of openings distributed along the horizontal and vertical directions.

[0012] Preferably, the first support rods located in the same direction are arranged parallel to each other, the number of second support rods is the same as that of the first support rods and they correspond one-to-one, the second support rods are perpendicular to the first support rods, the first support rods and the adjacent second support rods have smooth transitions at their close ends, and the first support rods and the adjacent first support rods in different directions all have smooth transitions at their close ends.

[0013] Preferably, the connector includes a plurality of third and fourth support rods arranged sequentially from top to bottom. The third and fourth support rods are disposed on the outer periphery of the support layer, and the third and fourth support rods cooperate to fix the support layer and the support plate.

[0014] Preferably, the outer wall of the base layer is provided with an included angle around its perimeter, the third support rod is disposed within the included angle, and the two ends of the third support rod smoothly transition with the base layer and another base layer or support plate located at the top of the base layer, respectively. The fourth support rod is disposed on the outer wall of the base layer, and the two ends of the fourth support rod smoothly transition with the base layer and another base layer or support plate located at the top of the base layer, respectively.

[0015] Compared with the prior art, the present invention has the following advantages and technical effects:

[0016] This invention divides the scaffold into a flow-blocking layer and a support layer, arranged sequentially from top to bottom. During cartilage transplantation, the flow-blocking layer, with its flush end face and made of porous material, contacts the human cartilage layer, blocking blood flow that affects the differentiation of upper cells into chondrocytes. This also reduces the flow of synovial fluid to the lower cells, promoting osteoblast formation. Furthermore, the uneven end face of the support layer disperses the force to the support layer when it comes into contact with the surrounding tissue of the transplantation area, as the scaffold as a whole is under stress. The uneven tips of the support layer stimulate the growth of cancellous bone. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall device.

[0019] Figure 2 This is a schematic diagram showing the connection between the base plate and the supporting layer;

[0020] Figure 3 for Figure 2 Top view of the structure;

[0021] Figure 4 This is a schematic diagram of the basic structure;

[0022] Figure 5 for Figure 4 Top view;

[0023] Figure 6 Diagram showing the positional relationship between the connecting hole and the guide hole;

[0024] Figure 7 for Figure 6 Structural side view;

[0025] Among them, 1. bracket; 2. flow-blocking layer; 3. support layer; 4. support plate; 5. bottom plate; 6. top plate; 7. connecting hole; 8. guide hole; 9. first support rod; 10. second support rod; 11. third support rod; 12. fourth support rod. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] Example:

[0029] Reference Figure 1-7The present invention provides an osteocartilage scaffold, including a scaffold 1. The scaffold 1 includes a flow-blocking layer 2 and a support layer 3 arranged sequentially from top to bottom. The flow-blocking layer 2 is a porous matrix layer with a flat end face, and the support layer 3 is a structural layer with an uneven end face. The support layer 3 is formed by several base layers arranged sequentially from top to bottom. The base layers have several openings in both the transverse and longitudinal directions.

[0030] Among them, the uppermost base layer is fixedly connected to the flow-blocking layer 2, and adjacent base layers are fixedly connected to each other.

[0031] Several base layers and the outer periphery of the flow-blocking layer 2 are fixedly connected to each other by connectors.

[0032] This invention divides the scaffold 1 into a flow-blocking layer 2 and a support layer 3, with the flow-blocking layer 2 and the support layer 3 arranged sequentially from top to bottom. During cartilage transplantation, the flow-blocking layer 2, with its flush end face and made of porous material, contacts the human cartilage layer, blocking blood flow that affects the differentiation of upper cells into chondrocytes. It also reduces the flow of synovial fluid down to the lower cells, promoting the formation of osteocytes. Furthermore, the uneven end face of the support layer 3, when in contact with the tissues surrounding the transplantation area, distributes the force to the support layer 3 due to the overall stress on the scaffold 1. The uneven tip of the support layer 3 stimulates the growth of cancellous bone.

[0033] Meanwhile, the scaffold 1 is preferably, but not limited to, made of TC4 or PEEK using reinforced 3D printing technology, and the support layer 3 is composed of several base layers. During cartilage transplantation, medical staff cut the scaffold 1 according to the area of ​​the patient's transplantation area. After the scaffold 1 is subjected to external force, the support layer 3 is compressed. The cut base layer sidewall ports are further enlarged, thereby increasing the maximum range of the support layer 3 under compression force and increasing the reaction force of the deformation of the support layer 3. By utilizing the interaction of forces to repeatedly exert force on human tissue, the promotion effect on cancellous bone growth is further enhanced.

[0034] In this technical solution, the barrier layer preferably contains, but is not limited to, polymers such as chitosan, chondroitin sulfate, collagen (type 1 and type 2), gelatin, hyaluronic acid, fibrin, polylactic acid (PLA), polycaprolactone (PCL), polyvinyl alcohol (PVA), glycosaminoglycans (GAGs), GAG-like polysaccharides, and tetraethylene glycol. The support layer 3 preferably contains, but is not limited to, polymers such as gelatin, polylactic acid (PLA), polycaprolactone (PCL), hyaluronic acid, fibrin, and chitosan.

[0035] Furthermore, the flow-blocking layer 2 includes a support plate 4, the top end face of the support plate 4 is flush, the support plate 4 is coaxially arranged with several base layers, and the end face area of ​​the support plate 4 is smaller than the end face area of ​​the base layers, the end face of the base layers is composed of several conical structures.

[0036] The support layer 3 is composed of several base layers with conical structures. While fully improving the support capacity of the scaffold 1, it also increases the range of movement of the outer edge of the support layer 3. When the support plate 4 contacts the patient's cartilage layer, the end face of the base layer is larger than that of the support plate 4, thus extending into the patient's human tissue. This allows the support layer 3, except for the contact surface with the support plate 4, to provide external force stimulation to the human tissue on all other end faces. This enhances the cell enrichment capacity in the circumferential direction within the cartilage transplantation area, thereby strengthening the repair capacity of the cartilage in the transplantation area.

[0037] Furthermore, the support plate 4 includes a bottom plate 5 and a top plate 6. The bottom plate 5 is fixedly connected to the base layer. The bottom plate 5 has several through holes in the vertical direction. The through holes are arranged in a matrix on the bottom plate 5. The top plate 6 is fixedly connected to the top of the bottom plate 5 and covers the several through holes.

[0038] In one embodiment of this technical solution, the support plate 4 is preferably, but not limited to, a porous inorganic salt layer (PEEK or PLA or PLGA + collagen type II), with a pore size of 3-10μm, a porosity of 60%, and a thickness preferably, but not limited to, 2.5mm. When in contact with the cartilage layer, the bottom plate 5 is fixed to the base layer, and the top plate 6 is in contact with the cartilage layer to effectively block the sliding joint and greatly reduce the flow of synovial fluid.

[0039] Furthermore, the support plate 4 is an integrally formed structure, with several connecting holes 7 at the top and several guide holes 8 on the side wall of the support plate 4, and the connecting holes 7 and guide holes 8 are connected.

[0040] Furthermore, the cross-sections of both the connecting hole 7 and the guide hole 8 are isosceles triangles.

[0041] In another embodiment of this technical solution, refer to Figure 6-7 The support plate 4 is an integral structure, and it has a connecting hole 7 and a guide hole 8 connected to the connecting hole 7. Since the guide hole 8 is located on the side wall of the support plate 4, when the synovial fluid flows down, it is guided to the edge of the human tissue through the connecting hole 7, thereby reducing the impact of synovial fluid migration on bone cell growth. At the same time, the channel in the support plate 4 can significantly promote cell migration. Moreover, the channel of this patent is an isosceles triangular structure. Compared with the traditional circular channel, when the support plate 4 comes into contact with the patient's cartilage layer, the deformed triangular structure of the support plate 4 is more likely to retain pores, effectively avoiding the large-area blockage of the connecting hole 7 by the cartilage layer, and improving the actual effect of guiding the drainage of synovial fluid.

[0042] Furthermore, the base layer includes several first support rods 9 and second support rods 10 spaced apart along the horizontal and vertical directions. The first support rods 9 and second support rods 10 are staggered and cooperate to form several openings distributed along the horizontal and vertical directions.

[0043] Furthermore, several first support rods 9 located in the same direction are arranged parallel to each other, and the number of second support rods 10 is the same as that of the first support rods 9 and they correspond one-to-one. The second support rods 10 are perpendicular to the first support rods 9. The first support rods 9 and the adjacent second support rods 10 have smooth transitions at their close ends, and the first support rods 9 also have smooth transitions at their close ends with several adjacent first support rods 9 in different directions.

[0044] Reference Figure 4-5 The first support rod 9 and the second support rod 10 are arranged alternately, so that the support layer 3 retains a three-dimensional structure. The first support rod 9 and the second support rod 10 are arranged at an angle, so that their ends are conical protrusions. When in contact with human tissue, they can effectively enhance the external force stimulation of cells and strengthen the cell enrichment. In addition, the large number of pores in the support layer 3 can maintain the stem cell performance, provide sufficient osteogenic niches for bone formation, and prevent cell differentiation.

[0045] Furthermore, the connector includes several third support rods 11 and fourth support rods 12 arranged sequentially from top to bottom. The third support rods 11 and fourth support rods 12 are disposed on the outer periphery of the support layer 3, and the third support rods 11 and fourth support rods 12 cooperate to fix the support layer 3 and the support plate 4.

[0046] Furthermore, an included angle is provided around the outer wall of the base layer, and the third support rod 11 is set inside the included angle. The two ends of the third support rod 11 smoothly transition with the base layer and another base layer or support plate 4 located at the top of the base layer, respectively. The fourth support rod 12 is set on the outer wall of the base layer, and the two ends of the fourth support rod 12 smoothly transition with the base layer and another base layer or support plate 4 located at the top of the base layer, respectively.

[0047] Reference Figure 1-5 After the first support rod 9 and the second support rod 10 are arranged in a staggered manner along the horizontal and vertical directions, a vertical angle is formed around their outer periphery. Using the third support rod 11, which is in the shape of an inverted "V" with its two ends and the middle at different horizontal heights, the extended ends of the first support rod 9 and the second support rod 10 located on the initial horizontal plane are fixed to the connecting ends of the corresponding first support rod 9 and the second support rod 10 in the upper layer or the bottom end of the support plate 4. This achieves the connection and fixation of several base layers to the support plate 4. Furthermore, the fourth support rod 12 is cross-fixed on the outer end face of the support layer 3, which further improves the structural strength of the overall support scaffold 1 and enhances the interaction of forces, thereby promoting cell enrichment and growth.

[0048] In one embodiment of the present invention, the smooth transitions described in this patent are all connection methods prepared by 3D printing, which is prior art and will not be described in detail.

[0049] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0050] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An osteochondral scaffold, characterized by: Includes a support (1), the support (1) includes a flow-blocking layer (2) and a support layer (3) arranged sequentially from top to bottom. The flow-blocking layer (2) is a porous matrix layer with flat end faces, and the support layer (3) is a structural layer with uneven end faces. The support layer (3) is formed by several base layers arranged sequentially from top to bottom. The base layers have several openings in both the horizontal and vertical directions. Among them, the uppermost base layer is fixedly connected to the flow-blocking layer (2), and adjacent base layers are fixedly connected to each other; The outer periphery of several of the base layers and the flow-blocking layer (2) are fixedly connected to each other by connectors; The flow-blocking layer (2) includes a support plate (4), the top end face of the support plate (4) is flush, the support plate (4) is coaxially arranged with several of the base layers, and the end face area of ​​the support plate (4) is smaller than the end face area of ​​the base layer. The end face of the base layer is composed of several conical structures. When the support (1) is subjected to external force in the circumferential direction, it squeezes the support layer (3), causing the support layer (3) to deform and providing a reaction force to the human tissue.

2. The osteochondral scaffold of claim 1, wherein: The support plate (4) includes a bottom plate (5) and a top plate (6). The bottom plate (5) is fixed to the base layer. The bottom plate (5) has several through holes in the vertical direction. The through holes are arranged in a matrix on the bottom plate (5). The top plate (6) is fixed to the top of the bottom plate (5) and covers the several through holes.

3. The osteochondral scaffold of claim 1, wherein: The support plate (4) is an integrally formed structure. The top of the support plate (4) is provided with several connecting holes (7), and the side wall of the support plate (4) is provided with several guide holes (8). The connecting holes (7) are connected to the guide holes (8).

4. The osteocartilage scaffold according to claim 3, characterized in that: The cross-sections of the connecting hole (7) and the guiding hole (8) are both isosceles triangles.

5. The osteochondral scaffold of claim 1, wherein: The base layer includes a number of first support rods (9) and second support rods (10) spaced apart along the horizontal and vertical directions. The first support rods (9) and the second support rods (10) are staggered and cooperate to form a number of openings distributed along the horizontal and vertical directions.

6. The osteocartilage scaffold according to claim 5, characterized in that: A plurality of first support rods (9) located in the same direction are arranged parallel to each other. The number of second support rods (10) is the same as that of the first support rods (9) and they correspond one-to-one. The second support rods (10) are perpendicular to the first support rods (9). The first support rods (9) and the adjacent second support rods (10) have a smooth transition at their respective close ends. The first support rods (9) and the adjacent first support rods (9) in different directions also have a smooth transition at their respective close ends.

7. The osteocartilage scaffold according to claim 1, characterized in that: The connector includes a number of third support rods (11) and fourth support rods (12) arranged from top to bottom. The third support rods (11) and the fourth support rods (12) are disposed on the outer periphery of the support layer (3). The third support rods (11) and the fourth support rods (12) cooperate to fix the support layer (3) and the support plate (4).

8. The osteochondral scaffold of claim 7, wherein: The outer wall of the base layer is provided with an included angle around its perimeter. The third support rod (11) is located within the included angle. The two ends of the third support rod (11) smoothly transition to the base layer and another base layer or support plate (4) located at the top of the base layer, respectively. The fourth support rod (12) is provided on the outer wall of the base layer. The two ends of the fourth support rod (12) smoothly transition to the base layer and another base layer or support plate (4) located at the top of the base layer, respectively.

Images