Degradable bone plate

Abstract

The utility model provides a kind of degradable bone plate, the degradable bone plate is made of degradable material, the degradable bone plate includes reinforcing frame, multiple pressurizing locking frames being arranged in the reinforcing frame, the connecting structure of connecting reinforcing frame and multiple pressurizing locking frames, the connecting structure includes multiple layers of support rods being arranged along the direction of thickness, the support rod of each layer is mutually overlapped to form lattice, the rod diameter of the support rod of each layer gradually increases from the side close to bone surface to the side away from bone surface.The degradable bone plate of the utility model is made of degradable material, so as to shorten the hospitalization time of user, avoid secondary removal operation;By setting, the rod diameter gradient of the support rod forming lattice gradually changes, effectively improves stress shielding effect, simultaneously realizes gradient degradation, improves bone integration efficiency, improves patient recovery speed.

Description

Technical Field

[0001] This utility model relates to a biodegradable bone plate. Background Technology

[0002] Bone plates are typically made of stainless steel, titanium, or titanium alloys. However, prolonged implantation of bone plates can cause a series of problems. For example, a mismatch in the elastic modulus between the plate and the bone tissue at the implantation site can lead to stress shielding, negatively impacting bone healing. Furthermore, prolonged implantation can cause the plate to loosen. These adverse effects often necessitate a second surgery to remove the implanted plate, further increasing patient suffering and financial burden. With changing treatment philosophies, there is a growing desire for medical implants that can temporarily perform repair functions and remain in the body, matching the tissue's repair process. After fulfilling their mechanical and biological functions, these implants should gradually degrade into absorbable or excretable degradation products, eventually leading to complete degradation and absorption. Therefore, the emergence of biodegradable medical materials has sparked a surge in research.

[0003] However, existing homogeneous bone plates made of biodegradable materials cannot achieve a gradient transition between early high-strength support and later flexible load, resulting in low osseointegration efficiency; regular porous bone plates lack heterogeneous topology mimicking bone trabeculae, resulting in insufficient structure-function synergy.

[0004] In view of this, it is necessary to improve existing biodegradable bone plates to solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a biodegradable bone plate. The biodegradable bone plate is made of biodegradable material and includes a reinforcing frame, a plurality of pressure locking frames disposed within the reinforcing frame, and a connecting structure connecting the reinforcing frame and the plurality of pressure locking frames. The connecting structure includes multiple layers of support rods disposed along the thickness direction. The support rods of each layer overlap each other to form a lattice, and the diameter of the support rods of each layer gradually increases from the side closer to the bone surface to the side farther away from the bone surface.

[0006] As a further improvement of this utility model, the pressure locking frame is formed with a pressure hole and a locking hole, and the pressure hole and the locking hole are interconnected.

[0007] As a further improvement of this utility model, the inner wall of the locking hole is threaded.

[0008] As a further improvement of this utility model, the biodegradable bone plate is made by 3D printing and the threads in the locking hole are milled by machining process.

[0009] As a further improvement of this utility model, the line connecting the centers of the pressure hole and the locking hole is in the same direction as the extension of the biodegradable bone plate.

[0010] As a further improvement of this utility model, the support rod is a smooth and continuous straight rod.

[0011] As a further improvement of this utility model, the material of the biodegradable bone plate is silk fibroin.

[0012] As a further improvement of this utility model, the lattice formed by each layer of the support rod gradually decreases in size from the side closer to the bone surface toward the side farther away from the bone surface.

[0013] As a further improvement of this utility model, a plurality of the pressure locking frames are spaced apart along the length direction of the biodegradable bone plate.

[0014] The beneficial effects of this invention are as follows: The biodegradable bone plate of this invention, made from biodegradable materials, can shorten the patient's hospital stay and avoid a second removal surgery. The interlocking support rods form a lattice structure, and by designing a gradient in the rod diameter, gradient degradation is achieved. The degradation rate of the material can be precisely controlled by adjusting the rod diameter. Simultaneously, it effectively improves the stress shielding effect, increases bone integration efficiency, and accelerates patient recovery. Furthermore, both the front and back sides are composed of smooth, continuous rods, with interconnected lattices, which improves the fatigue strength of the structure compared to discontinuous truncated lattices. Silk fibroin has good biocompatibility and, compared to metal-based biodegradable materials, naturally possesses the ability to promote cell adhesion, proliferation, and differentiation, directly supporting tissue regeneration. Its degradation products do not cause inflammation or immune responses. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 This is a schematic diagram of the side of the biodegradable bone plate of this utility model away from the bone surface;

[0017] Figure 2 This is a schematic diagram of the biodegradable bone plate of this utility model on the side near the bone surface;

[0018] Figure 3 yes Figure 2 A magnified structural diagram of region A in the middle;

[0019] Figure 4 This is a schematic diagram of the reinforcing frame of the biodegradable bone plate of this utility model;

[0020] Figure 5 This is a schematic diagram of the pressure locking frame of the biodegradable bone plate of this utility model;

[0021] Figure 6 This is a biodegradable bone plate of the present invention. Detailed Implementation

[0022] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not 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 utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0025] like Figures 1 to 6 As shown, the biodegradable bone plate 100 of this utility model is made of biodegradable material. The biodegradable bone plate 100 includes a reinforcing frame 1, a plurality of pressure locking frames 2 disposed in the reinforcing frame 1, and a connecting structure 3 connecting the reinforcing frame 1 and the plurality of pressure locking frames 2.

[0026] The biodegradable bone plate 100 is manufactured using 3D printing.

[0027] In this embodiment, the biodegradable bone plate 100 is made of silk fibroin. Silk fibroin is completely biodegradable. Compared to traditional inert bone plates, the biodegradable bone plate 100 made of silk fibroin can avoid tissue damage caused by secondary surgery, and the decrease in mechanical properties and the rate of tissue regeneration are more easily synchronized during the degradation process, thus avoiding tissue damage caused by secondary surgery and reducing patient suffering.

[0028] The reinforcing frame 1 is a homogeneous structure on the outermost ring, and the reinforcing frame 1 serves a supporting function.

[0029] Multiple pressure locking frames 2 are spaced apart along the length of the biodegradable bone plate 100. Each pressure locking frame 2 has a pressure hole 21 and a locking hole 22, which are interconnected. The inner wall of the locking hole 22 is threaded to achieve a stable fit with the locking screw, fixing the fracture site in the early stages of fracture. The locking screw and pressure screw can also be made of silk fibroin, but a homogeneous structure is used to improve strength. In this embodiment, the diameter of the pressure hole 21 is larger than that of the locking hole 22, and the threads are formed using a cold isostatic pressing process. This, combined with the silk fibroin locking screw, achieves dynamic pressure fixation, allowing for moderate micro-movement of the fracture ends to stimulate callus growth 3-5 days post-surgery.

[0030] When the biodegradable bone plate 100 is a cuboid, the line connecting the centers of the pressure hole 21 and the locking 22 is in the same direction as the extension of the biodegradable bone plate 100.

[0031] The pressure locking frame 2 can be manufactured by machining after 3D printing the biodegradable bone plate 100. Of course, if the accuracy requirements are met, the pressure locking frame 2 with threads can also be directly 3D printed.

[0032] The connection structure 3 includes multiple layers of support rods 31 arranged along the thickness direction. Each layer of support rods 31 overlaps each other to form a lattice. The diameter of each layer of support rods 31 gradually increases from the side closer to the bone surface toward the side farther from the bone surface.

[0033] In this embodiment, the lattice is a three-dimensional lattice formed by the support rods 31 of adjacent layers. The lattice formed by the support rods 31 of each layer gradually decreases in size from the side closer to the bone surface toward the side farther from the bone surface, thereby making the side closer to the bone surface easier to decompose.

[0034] Due to the gradient change in rod diameter, the gradient design of the structure is designed to facilitate the gradient degradation of the biodegradable bone plate 100, thereby enabling control over the degradation rate of the bone plate. Furthermore, as the diameter of the support rod 31 in the connecting structure 3 gradually increases, the rod diameter near the cortical bone surface of the biodegradable bone plate 100 is smaller, while the rod diameter further away from the cortical bone surface is larger. This gradient rod diameter design achieves a reduction in the elastic modulus gradient, effectively improving the stress shielding effect.

[0035] In this embodiment, the elastic modulus is continuously reduced by the gradient change in the diameter of the adjacent layer support rods 31, so that the degradation rate of the implant and the callus formation rate are precisely synchronized.

[0036] The support rod 31 is a smooth and continuous straight rod. This design enables the surface of the biomimetic bone trabeculae structure of the biodegradable bone plate 100 to reduce structural discontinuities such as grain boundaries, defects or dislocations, thereby reducing the risk of stress concentration and improving the material's resistance to deformation and load-bearing capacity.

[0037] The dynamic mechanical adaptability of the biodegradable bone plate 100 of this invention was verified through a four-point bending test. The stiffness of the implant remained at 8 GPa one week postoperatively, matching the needs of the initial stage of callus formation; by the sixth week, it decreased to 2.5 GPa, achieving mechanical matching with the newly formed bone tissue (1.8-3.0 GPa), effectively avoiding bone resorption caused by stress shielding effect. In the decomposition rate test of the biodegradable bone plate 100, the biodegradable bone plate 100 was placed in simulated body fluid. The biodegradable bone plate 100 exhibited a gradient degradation characteristic: the surface layer had a degradation rate of 20% after 6 months, the middle layer reached 50% after 12 months, and the deep layer retained 15% structural integrity after 24 months, providing continuous mechanical support for bone tissue regeneration.

[0038] The biodegradable bone plate 100 of this invention is made of biodegradable materials, which can shorten the patient's hospital stay and avoid a second removal surgery. By setting the support rods 31 that form the lattice to have a gradually changing diameter, the stress shielding effect is effectively improved, while gradient degradation is achieved, which improves the bone integration efficiency and the patient's recovery speed.

[0039] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0040] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A biodegradable bone plate, characterized in that: The biodegradable bone plate is made of biodegradable material. The biodegradable bone plate includes a reinforcing frame, a plurality of pressure locking frames disposed within the reinforcing frame, and a connecting structure connecting the reinforcing frame and the plurality of pressure locking frames. The connecting structure includes multiple layers of support rods disposed along the thickness direction. The support rods of each layer overlap each other to form a lattice. The diameter of the rods of each layer gradually increases from the side closer to the bone surface toward the side farther from the bone surface.

2. The biodegradable bone plate according to claim 1, characterized in that: The pressure locking frame has a pressure hole and a locking hole, which are interconnected.

3. The biodegradable bone plate according to claim 2, characterized in that: The locking hole has threads on its inner wall.

4. The biodegradable bone plate according to claim 3, characterized in that: The biodegradable bone plate is manufactured using 3D printing, and the threads in the locking holes are milled using machining processes.

5. The biodegradable bone plate according to claim 2, characterized in that: The line connecting the centers of the pressure hole and the locking hole is in the same direction as the extension of the biodegradable bone plate.

6. The biodegradable bone plate according to claim 1, characterized in that: The support rod is a smooth and continuous straight rod.

7. The biodegradable bone plate according to claim 1, characterized in that: The biodegradable bone plate is made of silk fibroin.

8. The biodegradable bone plate according to claim 1, characterized in that: The lattice formed by each layer of the support rod gradually decreases in size from the side closer to the bone surface toward the side farther away from the bone surface.

9. The biodegradable bone plate according to claim 1, characterized in that: Multiple pressure locking frames are spaced apart along the length of the biodegradable bone plate.

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