Periosteal distraction device

Abstract

The application provides a periosteum distraction device, which comprises a distraction plate and a support device, the support device comprises a first degradable layer arranged outside, a second degradable layer arranged in the first degradable layer in a radial direction, a support rod arranged in the middle of the second degradable layer, and a through channel reserved in the first degradable layer in an axial direction; the first degradable layer, the second degradable layer and the distraction plate are all made of degradable materials; the support device has a first end connected with the distraction plate and an opposite second end, the first degradable layer and the second degradable layer are configured to have a gradually slower degradation rate from the first end to the second end, and the degradation rate of the first degradable layer is slower than that of the second degradable layer; the distraction plate has a shape memory traction member, and the shape memory traction member passes through the through channel. The periosteum distraction device provided by the application can realize automatic distraction, has precise distraction degree, and does not need to take out the distraction plate after recovery, so that the patient is free from secondary injury.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to periosteal traction devices. Background Technology

[0002] Current periosteal traction plates require daily manual adjustment of the periosteal tension, a rather cumbersome process. Furthermore, the traction plates are made of metal, whose rigidity is far greater than that of skin. This causes concentrated stress on the skin at both ends of the traction plate, resulting in tissue redness, swelling, and pain. A second removal is necessary after healing, which can cause secondary damage to the body. Summary of the Invention

[0003] The purpose of this invention is to provide a periosteal traction device that can automatically adjust the degree of traction without requiring manual adjustment by the patient, and the degree of traction is more precise; at the same time, the main material is a biodegradable material that can degrade on its own, and the traction plate does not need to be removed after healing, thus avoiding secondary injury to the patient.

[0004] To achieve the above-mentioned objectives, the present invention provides a periosteal traction device, comprising a traction plate and a support device. The support device includes a first degradation layer disposed on the outside, a second degradation layer disposed radially within the first degradation layer, and a support rod disposed in the middle of the second degradation layer. An axial through-channel is pre-reserved within the first degradation layer. The first degradation layer, the second degradation layer, and the traction plate are all made of biodegradable material. The support device has a first end connected to the traction plate and a second end opposite to it. The first and second degradation layers are configured such that their degradation rates gradually decrease from the first end to the second end, and the degradation rate of the first degradation layer is slower than that of the second degradation layer. A shape memory traction element is provided within the traction plate, and the shape memory traction element extends through the through-channel.

[0005] The present invention also has the following features: the first degradation layer is a dense layer simulating the cortical bone structure, and the second degradation layer is a porous layer simulating the cancellous bone structure.

[0006] The present invention also has the following feature: the thickness of the first degradation layer increases from the first end to the second end.

[0007] The present invention also has the following feature: the density of the second degradation layer increases from the first end to the second end.

[0008] The present invention also has the following features: the second degradation layer is a fibrous structure made of the degradable material, and the fiber diameter of the fibrous structure increases from the first end to the second end.

[0009] The present invention also has the following features: the support device is connected to the tension plate through a ring clamp, the ring clamp includes an annular body and a plurality of ring clamping arms extending axially from the bottom of the annular body, a through hole of the ring clamp is provided at the center of the annular body along the axial direction, a stepped hole is provided on the side of the through hole near the annular body, the support rod passes through the through hole, and the first degradation layer and the second degradation layer are inserted into the stepped hole.

[0010] The present invention also has the following features: the circumferential arm is made of shape memory alloy, and the circumferential arm curls outward when heated.

[0011] The present invention also has the following feature: the annular body has a fluid flow channel, which connects the inner and outer sides of the stepped hole.

[0012] The present invention also has the following feature: the outer side of the shape memory traction component has a temperature-sensitive and biodegradable coating.

[0013] The present invention also has the following features: the tension plate includes a first tension plate and a second tension plate, the first tension plate and the second tension plate are detachably connected; the first end of the second tension plate has a circular connecting portion, the first end of the first tension plate has a groove and a baffle covering the groove, and the circular connecting portion is inserted into the groove and fixed.

[0014] The present invention also has the following features: the periosteal traction device includes a suture wrapping dressing, the suture wrapping dressing has a lead hole, a shape memory traction member passes through the lead hole, and a one-way valve is provided in the lead hole to fix the shape memory traction member after it passes through the lead hole.

[0015] The present invention also has the following features: the shape memory traction component includes shape memory alloy wire, shape memory alloy strip or shape memory alloy mesh.

[0016] The present invention also has the following feature: the support device is prepared by a method comprising the following steps:

[0017] A1: Electrospinning is performed on the outside of the support rod using a biodegradable material solution. From the first end to the second end, the spun filament diameter changes from thin to thick and from sparse to dense, thus creating a second degradable layer.

[0018] A2: Place the shape memory traction component prototype outside the second degradation layer, and then coat it with a biodegradable material solution to form the first degradation layer.

[0019] The present invention also has the following feature: the biodegradable material includes silk fibroin, polylactic acid, polyglycolic acid or polycaprolactone.

[0020] The periosteal traction device provided by this invention uses biodegradable materials for both the traction plate and the support device, making them harmless to the human body. The traction plate, as well as the second and first degradation layers, degrade on their own and do not need to be removed after healing, preventing secondary injury to the patient. The shape memory traction component provides continuous tension, achieving linear automatic traction in conjunction with the support device. After implantation, the periosteal traction device comes into contact with body fluids. The second degradation layer degrades first, then gradually becomes hollow due to loss of support, unable to withstand the tension of the traction plate and collapses. The first degradation layer, due to its slower degradation rate, supports the second degradation layer and does not interfere with the subsequent traction process. The first degradation layer prevents body fluid from spreading to the surrounding area of ​​the support device, allowing it to penetrate only from the bottom up. Only after the bottommost second degradation layer is completely degraded will the upper layers gradually come into contact with body fluids and degrade layer by layer, ensuring a stable and controllable degradation process and providing reliable assurance for continuous traction. Attached Figure Description

[0021] Figure 1 This is a structural diagram of the periosteal traction device of the present invention;

[0022] Figure 2 This is a structural diagram of the tension plate of the present invention;

[0023] Figure 3 This is a structural diagram of the first tension plate of the present invention;

[0024] Figure 4 This is a structural diagram of the second tension plate of the present invention;

[0025] Figure 5 This is a structural diagram of the support device of the present invention;

[0026] Figure 6 This is a structural diagram of the circumferential device of the present invention;

[0027] Figure 7 This is a cross-sectional view of the periosteal traction device of the present invention;

[0028] Figure 8 This is a structural diagram of the winding dressing of the present invention. Detailed Implementation

[0029] The technical solution of the present invention 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 the present invention. 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.

[0030] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 invention based on the specific circumstances. Furthermore, the technical features involved in the different embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0032] like Figures 1-8 As shown, a periosteal traction device includes a traction plate 1 and a support device 2. The support device 2 includes a first degradable layer 21 disposed on the outside, a second degradable layer 22 disposed radially within the first degradable layer 21, and a support rod 24 disposed in the middle of the second degradable layer 22. A through channel 23 is pre-reserved axially within the first degradable layer 21. The first degradable layer 21, the second degradable layer 22, and the traction plate 1 are all made of biodegradable materials. The support device 2 has a first end connected to the traction plate 1 and a second end opposite to it. The first degradable layer 21 and the second degradable layer 22 are configured such that the degradation rate gradually decreases from the first end to the second end, and the degradation rate of the first degradable layer 21 is slower than that of the second degradable layer 22. The traction plate 1 has a shape memory traction element 5, which extends through the through channel 23. The periosteal traction device provided by this invention can automatically adjust the degree of traction according to the individual patient's condition, without requiring manual intervention from the patient, thus significantly improving the safety and effectiveness of traction therapy. Its core material is biodegradable, and it can be removed without a second surgery after the tissue has healed, thus avoiding secondary trauma to the patient.

[0033] After implantation, the periosteal traction device continuously generates restorative force at body temperature. Due to the excellent toughness of the traction plate, it simultaneously generates a continuous and stable restorative force under the drive of the shape memory traction device, thereby achieving continuous traction on the skin tissue. In the initial implantation stage, the support device provides support to the traction plate, counteracting the tension it generates and ensuring that the tissue adapts to the initial implantation state. According to one embodiment of the present invention, the shape memory traction device 5 includes a shape memory alloy wire, a shape memory alloy strip, or a shape memory alloy mesh.

[0034] According to one embodiment of the present invention, the support device adopts a bone-inspired biomimetic structure design, which is a two-layer composite structure: the first degradation layer is a dense layer simulating the cortical bone structure, and the second degradation layer is a porous layer simulating the cancellous bone structure. Upon contact with body fluids after implantation, the second degradation layer will degrade first, and subsequently, due to loss of support, it will gradually become hollow, unable to withstand the tension of the tension plate, and will collapse; while the first degradation layer, due to its slower degradation rate, will maintain support for the second degradation layer and will not interfere with the subsequent tension process.

[0035] In practical applications, the first degradation layer guides the body fluid to permeate from the bottom up, effectively preventing the fluid from spreading to the surrounding area of ​​the support device. Only after the bottommost second degradation layer is completely degraded will the upper layers gradually come into contact with the body fluid and degrade layer by layer, thus ensuring that the entire degradation process is stable and controllable, providing a reliable guarantee for continuous tension.

[0036] According to one embodiment of the present invention, the thickness of the first degradable layer 21 increases from the first end to the second end. The upper end of the first degradable layer has a greater thickness of degradable material and a longer degradation period in vivo, which can provide long-term and stable axial mechanical support for the periosteal traction device throughout the entire bone healing cycle, matching the physiological load-bearing characteristics of the host cortical bone.

[0037] According to one embodiment of the present invention, the density of the second degradation layer 22 increases from the first end to the second end. According to another embodiment of the present invention, the second degradation layer is a fibrous structure made of the degradable material, and the fiber diameter of the fibrous structure increases from the first end to the second end. The lower density or smaller diameter fibers at the lower end of the second degradation layer correspond to a faster degradation rate, enabling early targeted and rapid degradation after implantation; the increasing density or fiber diameter at the upper end of the second degradation layer corresponds to a synchronously slower degradation rate, forming a precise match with the long-term support performance of the first degradation layer.

[0038] According to one embodiment of the present invention, the support device 2 is connected to the tension plate 1 via a ring 3. The ring 3 includes an annular body 31 and a plurality of ring arms 32 extending axially from the bottom of the annular body 31. A through hole 33 of the ring 31 is provided axially at the center of the annular body 31. A stepped hole 34 is provided on the side of the through hole 33 near the annular body 31. The support rod 24 passes through the through hole 33, and the first degradation layer 21 and the second degradation layer 22 are inserted into the stepped hole 34.

[0039] The encircling device 3 is threadless, avoiding the risks of loosening, stripping, and breakage of threaded connections. It significantly simplifies the surgical procedure, eliminating the need for additional tapping, screw insertion, and other thread assembly steps, thus shortening surgical time, lowering the surgeon's skill threshold, and reducing the number of specialized instruments used during surgery, thereby improving efficiency. Simultaneously, it eliminates the stress concentration problem inherent in threaded structures, optimizing the biomechanical distribution at the fixation site and reducing the risk of stress shielding and bone resorption in the implant area. Furthermore, the smooth structure without threaded grooves facilitates cleaning and sterilization, reducing the risk of bacterial colonization and postoperative infection.

[0040] According to one embodiment of the present invention, the circumferential retainer 3 is made of shape memory alloy, and the circumferential arm 32 curls outward when heated. The circumferential retainer 3 also serves to fix a split periosteal traction plate, which results in a smaller implantation wound. According to this embodiment, the circumferential retainer 3 relies on the shape memory effect and superelasticity of the shape memory alloy to achieve self-locking stable fixation by triggering deformation at body temperature. This provides continuous and uniform clamping force, avoiding surgical complications such as traction plate displacement and loss of periosteal traction effect caused by postoperative fixation failure.

[0041] In addition, the circumferential device 3, through the cooperation of the stepped hole 34 and the through hole 33, makes the end of the support rod of the support device 2 protrude out of the tension plate 1 and press against the bone, thereby achieving tension on the periosteum.

[0042] According to one embodiment of the present invention, the annular body 31 has a fluid flow channel that connects the inner and outer sides of the stepped hole 34. Fluid enters the stepped hole through the fluid flow channel, causing the first degradation layer 21 and the second degradation layer 22 within the stepped hole to degrade. According to another embodiment of the present invention, the fluid flow channel connects to the bottom surface of the annular body 31 of the stepped hole 34, allowing fluid to flow upwards into the first degradation layer and the second degradation layer, thereby causing the first degradation layer and the second degradation layer to degrade. Simultaneously, the shape memory traction member 5 can also pass through the fluid flow channel.

[0043] According to one embodiment of the present invention, the outer side of the shape memory traction component 5 has a thermosensitive and biodegradable high-polymer coating. The thermosensitive and biodegradable high-polymer coating is a polymer film coated on the surface of a substrate, possessing temperature-responsiveness (thermosensitive), biodegradability / environmental biodegradability, and high adhesion / high functional density characteristics. The thermosensitive and biodegradable high-polymer coating includes absorbable bone waxes such as PLGA-PEG-PLGA triblock copolymer and polyethylene glycol (PEG) water-soluble wax. After periosteal traction is completed, the shape memory traction component 5 can be quickly removed by utilizing the characteristics of the thermosensitive and biodegradable high-polymer coating on its outer side.

[0044] According to one embodiment of the present invention, the traction plate includes a first traction plate 11 and a second traction plate 12, which are detachably connected. This allows for separate installation of the second traction plate 12 and the first traction plate 11 during clinical application, resulting in a smaller periosteal incision and less trauma to the periosteal membrane. The first end of the second traction plate 12 has a circular connecting portion 121, which reduces irritation to the skin and tissues, lowering the probability of skin irritation caused by sharp structures. The first end of the first traction plate 11 has a groove 111 and a baffle 112 covering the groove, with the circular connecting portion 121 inserted into and fixed to the groove 111. Specifically, the overlap length between the circular connecting portion 121 and the baffle 112 is between 8-12 mm. Too short a length reduces the stability of the periosteal traction plate during lifting, while too long a length increases installation difficulty; an overlap length of 8-12 mm ensures the stability of the periosteal traction plate.

[0045] According to one embodiment of the present invention, the periosteal traction device includes a suture dressing 4, which has a lead hole 41 through which a shape memory traction member 5 passes. A one-way valve is provided within the lead hole 41 to fix the shape memory traction member 5 after it passes through the lead hole 41. The suture dressing 4 is made of biocompatible materials such as PDMS or silicone through molding. PDMS has a hydrophobic structure and porous, flexible properties, making it difficult for granulation tissue to grow on it. It also has good antibacterial and biocompatibility, and will not cause secondary tearing of the wound after prolonged wear and removal. The suture dressing 4 is applied to the skin to protect the wound. The shape memory traction member 5 is fixed after passing through the lead hole, allowing for manual traction when needed. After passing through the lead hole, the shape memory traction member 5 can be coiled around the suture dressing 4 for storage of excess shape memory traction member 5. According to one embodiment of the present invention, the shape memory traction component 5 includes a shape memory alloy wire, a shape memory alloy strip, or a shape memory alloy mesh.

[0046] According to an embodiment of the present invention, the method for manufacturing the tension plate 1 includes:

[0047] A thermosensitive, biodegradable coating is applied to the surface of the shape memory traction device. This coating essentially occupies some space beforehand. After treatment, heating the shape memory traction device melts the thermosensitive, biodegradable coating, creating a movable area for the device and facilitating its removal. Specifically, the tension plate 1 has a channel for the shape memory traction device to pass through, and the device is detachably mounted within the tension plate and the through channel. The thermosensitive, biodegradable coating includes absorbable bone waxes such as PLGA-PEG-PLGA triblock copolymer and polyethylene glycol (PEG) water-soluble wax.

[0048] A shape memory traction component with a surface coated with a temperature-sensitive and biodegradable high-coating is placed in a tension plate mold;

[0049] Biodegradable material is poured into a mold, and after solidification, the tension plate is removed, ground, polished, and deburred. The required threaded holes are then machined. At this point, the shape memory traction component extends from the connection between the first and second tension plates. Nutrients or anti-inflammatory drugs can also be added to the biodegradable material solution during the fabrication of the tension plate. The finished tension plate will have a certain degree of toughness, allowing deformation under the action of the shape memory traction component. According to one embodiment of the present invention, the shape memory traction component includes shape memory alloy wire, shape memory alloy strip, or shape memory alloy mesh. According to one embodiment of the present invention, the biodegradable material is silk fibroin.

[0050] According to one embodiment of the present invention, a tension plate is made by coating the surface of the shape memory alloy wire with a low-temperature biodegradable wax and then integrally casting a silk protein solution. The degradation time of the silk protein tension plate is much longer than that of the support device. After use, the shape memory alloy wire and the support rod can be easily removed by applying a hot towel at about 50°C to one end of the support device that is close to the skin for a period of time.

[0051] According to an embodiment of the present invention, the support device 2 is prepared by a method comprising the following steps:

[0052] A1: Electrospinning is performed on the outside of the support rod using a biodegradable material solution. From the first end to the second end, the spun filament diameter changes from thin to thick and from sparse to dense, thus creating a second degradable layer.

[0053] A2: Place the shape memory traction component prototype outside the second degradation layer, and then coat it with a biodegradable material solution to form the first degradation layer.

[0054] According to one embodiment of the present invention, the biodegradable material includes silk fibroin, polylactic acid, polyglycolic acid, or polycaprolactone.

[0055] Electrospinning can form a dense and uniform fiber membrane structure, and the biodegradable material itself has hydrophobic properties, which can effectively limit the penetration of body fluid into the fiber structure and to the sides. Body fluid is only allowed to wet and contact the biodegradable material from the bottom. Thus, the interference of trace body fluid penetration in the fiber gaps on the degradation rate can be ignored, and the degradation behavior of the implant can be precisely and directionally controlled.

[0056] The purpose of the shape memory traction device trial mold is to leave space so that the device can pass through during clinical installation. The support rod can be made of materials such as metal, polymer, or biodegradable materials, serving to support and constrain the degree of freedom of degradation. Its surface is also coated with a temperature-sensitive biodegradable high-coating layer, which serves the same function as the shape memory traction device. After treatment, it is heated to melt the temperature-sensitive biodegradable high-coating layer before removal.

[0057] According to one embodiment of the present invention, the second degradation layer is prepared using an electrospinning process. The fiber structure is designed with a gradient, with the fiber diameter gradually increasing from thin to thick along the direction of body fluid wetting (i.e., from the first end to the second end of the support device), and the spinning density gradually increasing from sparse to dense. The electrospinning voltage is set to 20KV-12KV, with linear voltage regulation at a rate of 0.5~2kV / min, and a step-by-step single voltage regulation amplitude of less than or equal to 3kV. The remaining spinning parameters are kept constant throughout the process. A gradient degradation structure, with the fiber diameter increasing from the bottom to the top, can be achieved by gradually lowering the voltage from high to low. In addition, the conventional spinning voltage window is 12~20V, and the voltage regulation must not exceed the critical starting voltage (10~12kV) and the upper discharge limit voltage (25kV) throughout the process.

[0058] In the initial state, the shape memory traction component in the tension plate returns to its original shape under the influence of body temperature, causing the tension plate to bend and deform, at which point the tension plate has a certain curvature. Then, using a pin-holding tool, the first and second tension plates are installed into the body. The curvature of the tension plates, as well as the rounded corners and beveled edges at the ends, reduces resistance when the tension plates enter the body. This design eliminates the need for creating a space for the tension plate installation on the periosteum in advance, as required by traditional methods. After the tension plates are installed, the shape memory traction component is passed through the fluid channels of the circumferential device and the pre-reserved through-channel of the support device. Simultaneously, the support device is fixedly connected to the tension plate through the circumferential device, allowing the support rod of the support device to pass through the through-hole of the circumferential device. The first and second degradation layers of the support device are inserted into the stepped holes of the circumferential device, and then the pin-holding tool is removed.

[0059] The shape memory traction element, with its pre-exposed through-channel portion revealing the support device, is passed through the lead hole of the suture dressing. A one-way valve within the lead hole secures the shape memory traction element. The suture dressing is then placed on the skin wound to fix the support device in place. Besides securing the support device, the suture dressing also provides antibacterial and breathable properties, creating a moist environment and reducing scarring. The shape memory traction element, after being passed through the lead hole and secured, can also be manually stretched when needed. After passing through the lead hole, the shape memory traction element can be coiled around the suture dressing for storage of any excess.

[0060] After the periosteal traction device is implanted, the second degradation layer degrades first upon contact with bodily fluids. Subsequently, the second degradation layer gradually becomes hollow due to loss of support. Then, under the pressure of the traction plate, the lower part of the support device is gradually flattened, and the connection between the traction plate and the support device gradually tilts upward, achieving traction on the periosteal membrane. When the support device has completely degraded or is about to completely degrade, the internal support rod can be removed. Then, the shape memory traction component is heated to melt the temperature-sensitive biodegradable coating on its surface. The shape memory traction component is then removed, and the remaining components in the body can be allowed to degrade on their own. During this period, some periosteal traction effect will continue, and the degradation process will continue to produce nutrients for vascular recovery.

[0061] In summary, the periosteal traction device provided by this invention uses biodegradable materials for both the traction plate and the support device. The traction plate, as well as the second and first degradation layers, degrade on their own and do not need to be removed after healing, thus protecting the patient from secondary injury. The shape memory traction element can provide continuous traction tension, achieving linear automatic traction in conjunction with the support device.

[0062] After the periosteal traction device is implanted and comes into contact with body fluids, the second degradation layer degrades first. Subsequently, the second degradation layer gradually becomes hollow due to loss of support, unable to withstand the tension of the traction plate, and collapses. The first degradation layer, due to its slower degradation rate, supports the second degradation layer and does not interfere with the subsequent traction process. The first degradation layer prevents body fluids from diffusing to the surrounding area of ​​the support device, guiding the fluids to permeate from the bottom up. Only after the bottommost second degradation layer has completely degraded will the upper layers gradually come into contact with body fluids and degrade layer by layer, thus ensuring a stable and controllable degradation process and providing a reliable guarantee for continuous traction.

[0063] Furthermore, currently, no existing technology can simultaneously meet the dual core requirements of "degradability" and "automatic continuous traction" for periosteal traction devices. Traditional traction plates, while achieving a traction effect, lack biodegradability and require removal via secondary surgery. Degradable shape-memory plastic technologies are not yet mature, and their degradation rate is difficult to control precisely, compromising the stability of the traction process. Both of these solutions exhibit step-like fluctuations in traction effects, making it difficult to achieve continuous and stable traction. This invention, through the synergistic design of degradable and shape-memory traction components, and the biomimetic controllable degradation structure of the support device, ensures that the collapse of the support device is linear and stable, avoiding the step-like abrupt stress caused by traditional manual adjustments. This achieves precise control of the traction degree, resolving the aforementioned technical pain points.

[0064] It should be emphasized that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A periosteal traction device, the periosteal traction device comprising a traction plate (1) and a support device (2), characterized in that, The support device (2) includes a first degradable layer (21) disposed on the outside, a second degradable layer (22) disposed radially within the first degradable layer (21), and a support rod (24) disposed in the middle of the second degradable layer (22). A through channel (23) is reserved axially within the first degradable layer (21). The first degradable layer (21), the second degradable layer (22), and the tension plate (1) are all made of degradable materials. The support device (2) has a first end connected to the tension plate (1) and a second end opposite to it. The first degradable layer (21) and the second degradable layer (22) are all made of degradable materials. The two degradation layers (22) are configured such that the degradation rate gradually slows down from the first end to the second end, and the degradation rate of the first degradation layer (21) is slower than that of the second degradation layer (22); the periosteal traction device includes a suture dressing (4), which is placed at the skin wound to fix the support device (2); the traction plate (1) has a shape memory traction member (5), which passes through the through channel (23) and the suture dressing (4) and is fixed on the suture dressing (4); The tension plate (1) undergoes bending deformation under the action of the shape memory traction member (5); the first degradation layer (21) and the second degradation layer (22) degrade, and under the compression of the tension plate (1), the lower part of the support device (2) is gradually flattened, and the connection between the tension plate (1) and the support device (2) gradually tilts upward.

2. The periosteal traction device as described in claim 1, characterized in that, The first degradation layer (21) is a dense layer simulating the cortical bone structure, and the second degradation layer (22) is a porous layer simulating the cancellous bone structure.

3. The periosteal traction device as described in claim 1, characterized in that, The thickness of the first degradation layer (21) increases from the first end to the second end.

4. The periosteal traction device as described in claim 1, characterized in that, The density of the second degradation layer (22) increases from the first end to the second end.

5. The periosteal traction device as described in claim 1, characterized in that, The second degradation layer (22) is a fiber structure made of the degradable material, and the fiber diameter of the fiber structure increases from the first end to the second end.

6. The periosteal traction device as described in claim 1, characterized in that, The support device (2) is connected to the tension plate (1) via a ring holder (3). The ring holder (3) includes an annular body (31) and a plurality of ring arms (32) extending axially from the bottom of the annular body (31). A through hole (33) of the ring holder is provided at the center of the annular body (31) along the axial direction. A stepped hole (34) is provided on the side of the through hole (33) near the annular body (31). The support rod (24) passes through the through hole (33), and the first degradation layer (21) and the second degradation layer (22) are inserted into the stepped hole (34).

7. The periosteal traction device as described in claim 6, characterized in that, The circumferential retainer (3) is made of shape memory alloy, and the circumferential arm (32) curls outward when heated.

8. The periosteal traction device as described in claim 6, characterized in that, The annular body (31) has a fluid channel that connects the inner and outer sides of the stepped hole (34).

9. The periosteal traction device as described in claim 6, characterized in that, The shape memory traction component (5) has a thermosensitive and biodegradable coating on its outer side.

10. The periosteal traction device as described in claim 1, characterized in that, The tension plate (1) includes a first tension plate (11) and a second tension plate (12), which are detachably connected; the first end of the second tension plate (12) has a circular connecting part (121), the first end of the first tension plate (11) has a groove (111) and a baffle (112) covering the groove, and the circular connecting part (121) is inserted into the groove (111) and fixed.

11. The periosteal traction device as described in claim 1, characterized in that, The winding dressing (4) has a lead hole (41), and the shape memory traction member (5) passes through the lead hole (41). The lead hole (41) has a one-way valve, which fixes the shape memory traction member (5) after it passes through the lead hole (41).

12. The periosteal traction device as described in claim 1, 9, or 11, characterized in that, The shape memory traction component (5) includes shape memory alloy wire, shape memory alloy strip or shape memory alloy mesh.

13. The periosteal traction device as described in claim 1, characterized in that, The support device (2) is prepared by a method comprising the following steps: A1: Electrospinning is performed on the outside of the support rod using a biodegradable material solution. From the first end to the second end, the spun filament diameter changes from thin to thick and from sparse to dense, thus creating a second degradable layer. A2: Place the shape memory traction component prototype outside the second degradation layer, and then coat it with a biodegradable material solution to form the first degradation layer.

14. The periosteal traction device as described in claim 1 or 13, characterized in that, The biodegradable materials include silk protein, polylactic acid, polyglycolic acid, or polycaprolactone.

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