A biomedical degradable pure magnesium screw

Abstract

The present invention discloses a biomedical degradable pure magnesium screw, which belongs to the technical field of screws for fractures. The present invention comprises a fixing screw, wherein a telescopic component and an energy storage component are provided inside the fixing screw. The fixing screw is used to connect the fracture section. The telescopic component can protrude from the side of the fixing screw. The energy storage component can provide the telescopic component with a delayed force to protrude the fixing screw, so that the telescopic component can automatically extend. The material of the fixing screw and the telescopic component are both pure magnesium materials with a purity of not less than 99.99wt.%. The energy storage component is a material that can be absorbed by the human body. The present invention sets a telescopic component so that the telescopic component can protrude from the side of the fixing screw. The telescopic component protrudes from the side, thereby increasing the firmness of the fixing screw and preventing the fixing screw from spinning. In this way, the length of the fixing screw can be reduced, and a good fixing effect can be achieved, so that the sections are firmly connected.

Description

Technical Field

[0001] The present invention relates to the technical field of screws for fractures, and in particular to a biomedical degradable pure magnesium screw. Background Art

[0002] A fracture is a complete or partial break in a bone or bone structure. Fractures can be classified as either stable or unstable. Stable fractures are those in which the fracture ends are difficult to displace or re-displace after reduction, such as cleft fractures, greenstick fractures, transverse fractures, compression fractures, and impacted fractures. Unstable fractures are those in which the fracture ends are easily displaced or re-displaced after reduction, such as oblique fractures, spiral fractures, and comminuted fractures.

[0003] Since the fracture ends of unstable fractures are prone to displacement when subjected to external forces, it is difficult to maintain the stability of the fracture ends by relying solely on external fixation. In order to ensure smooth fracture healing and recovery of limb function, it is usually necessary to insert screws for internal fixation to provide more reliable stability and prevent the fracture ends from displacing again.

[0004] The screws are usually fixed perpendicular to the cross section. Figure 1 Taking oblique fractures as an example, the fractured bone forms an upper bone fragment 100 and a lower bone fragment 500. First, the cross-sections of the upper bone fragment 100 and the lower bone fragment 500 are spliced ​​together and then fixed with screws. Before connecting the screws, it is necessary to drill the corresponding screw holes with an electric drill and then screw in the screws. According to the distribution of the drill holes, the commonly used ones are the first screw hole 200, the second screw hole 300, the third screw hole 400 and the fourth screw hole 600. Among them, the first screw hole 200 and the second screw hole 300 are mainly used to fix the outer position of the bone fragment, while the third screw hole 400 is used to fix the middle position of the bone fragment. When the width of the bone is wide, the third screw hole 400 needs to be set to increase the stability of the fixation. However, the screw hole length of the third screw hole 400 is long, which will damage more normal bones and require a long screw. Long screws will also produce stress shielding, which is not conducive to bone recovery. To overcome the shortcomings of the third screw hole 400, a fourth screw hole 600 is provided. The fourth screw hole 600 is a blind hole formed in the cross-section of the upper and lower bone fragments 100, 500. The ends of the screws are then inserted into the blind holes on either side of the cross-section. The fourth screw hole 600 does not require significant damage to normal bone; the screws in the fourth screw hole 600 secure the upper and lower bone fragments 100, 500. However, the screws in the fourth screw hole 600 merely connect the upper and lower bone fragments 100, 500 through insertion. The screws in the fourth screw hole 600 are prone to misalignment during rotation, deviating from their original fixation point. This can cause the cross-sections of the upper and lower bone fragments 100, 500 to deviate, hindering cross-sectional healing. Summary of the Invention

[0005] In view of the above-mentioned shortcomings, the present invention provides a biomedical degradable pure magnesium screw, which can reduce and prevent the screw from loosening and rotating, thereby helping fracture patients recover.

[0006] The present invention protects a biomedical degradable pure magnesium screw, comprising a fixing screw, wherein a telescopic component and an energy storage component are provided in the fixing screw;

[0007] The fixing screw is used to connect the fracture sections;

[0008] The telescopic assembly can protrude from the side of the fixing screw;

[0009] The energy storage component can provide the telescopic component with a force that delays the protrusion of the fixing screw, so that the telescopic component can automatically extend;

[0010] The fixing screw and the telescopic component are both made of pure magnesium with a purity of not less than 99.99wt.%; the energy storage component is an elastic material that can be absorbed by the human body.

[0011] Furthermore, the fixing screw includes a screw body, a hollow cavity is provided in the screw body, and the telescopic assembly is provided in the hollow cavity;

[0012] A telescopic channel is further provided in the screw body. The telescopic channel is radially arranged in the side wall of the screw body. The telescopic channel is communicated with the hollow cavity, so that the telescopic assembly can extend from the telescopic channel.

[0013] Furthermore, a plurality of strip-shaped cavities are provided in the side wall of the screw body, and the plurality of strip-shaped cavities are distributed along the circumferential direction;

[0014] Each of the strip-shaped cavities is a closed cavity extending in a vertical direction.

[0015] Furthermore, adjacent strip-shaped cavities are connected through connecting channels.

[0016] Furthermore, a convex portion is provided on the side wall surface of the screw body, and the convex portion forms an external thread;

[0017] The top surface of the screw body is provided with a slot.

[0018] Furthermore, the telescopic assembly includes a rotatable rotating rod and a slider sleeved on the rotating rod, and the slider is movable along the axial direction of the rotating rod;

[0019] The slider is hinged to one end of the connecting rod, and the other end of the connecting rod is hinged to the fixed block;

[0020] The rotating rod is provided with a clamping piece, and the energy storage assembly can be clamped with the clamping piece to drive the rotating rod to rotate.

[0021] Furthermore, a notch is provided on the top side wall of the rotating rod, and the engaging member is the notch;

[0022] The top surface of the rotating rod is provided with a transverse groove.

[0023] Furthermore, the energy storage assembly includes an elastic member and a base, one end of the elastic member is fixed on the fixing screw, and the other end of the elastic member is a free end, and the free end can be engaged with the engaging member;

[0024] The elastic member can be deformed;

[0025] The base can fix the deformed elastic member.

[0026] Furthermore, the elastic member is a spring, and a hook is provided on the free end of the spring; the spring is made of pure magnesium with a purity of not less than 99.99wt.%.

[0027] Furthermore, the base is an ice cube.

[0028] Beneficial Effects: The present invention provides a telescopic component that can protrude from the side of the fixing screw. The telescopic component protrudes from the side and abuts against the wall of the screw hole, that is, the bone, thereby increasing the firmness of the fixing screw while also preventing the fixing screw from spinning. This can achieve a good fixing effect and firmly connect the cross-section. By providing an energy storage component, the fixing screw can be directly applied to the cross-section, that is, the fourth screw hole. After the fixing screw is placed in the fourth screw hole, the energy storage component provides a delayed force to the telescopic component, causing the telescopic component to extend, thereby achieving fixation and preventing the cross-section from moving. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0030] in:

[0031] Figure 1 A schematic diagram of an oblique fracture in the background art of the present invention;

[0032] Figure 2 This is a schematic diagram of the overall structure of a biomedical degradable pure magnesium screw in one embodiment of the present invention;

[0033] Figure 3 A top view of a biomedical degradable pure magnesium screw according to one embodiment of the present invention;

[0034] Figure 4 for Figure 3 Cross-section in the AA direction;

[0035] Figure 5 A partial cross-sectional view of a biomedical degradable pure magnesium screw according to an embodiment of the present invention;

[0036] Figure 6 This is a front view of a biomedical degradable pure magnesium screw according to one embodiment of the present invention;

[0037] Figure 7 for Figure 6 Cross-section in the CC direction;

[0038] Figure 8 A top view of a biomedical degradable pure magnesium screw according to another embodiment of the present invention;

[0039] Figure 9 for Figure 8 Cross-section in the middle DD direction;

[0040] Figure 10 is a cross-sectional view of a fixing screw in another embodiment of the present invention;

[0041] Figure 11 This is a schematic diagram of the overall structure of a telescopic assembly in one embodiment of the present invention;

[0042] Figure 12 A schematic diagram of the overall structure of an energy storage assembly in one embodiment of the present invention;

[0043] In the figure, 1, fixing screw; 11, screw body; 12, strip-shaped cavity; 13, connecting channel; 14, raised portion; 15, bottom groove; 16, hollow cavity; 161, central cavity; 162, side cavity; 17, telescopic channel; 18, top groove; 19, straight slot;

[0044] 2. Telescopic assembly; 21. Rotating rod; 211. Notch; 212. Horizontal groove; 22. Slider; 23. Connecting rod; 24. Fixed block;

[0045] 3. Energy storage component; 31. Spring; 311. Hook; 32. Base;

[0046] 100, upper bone fragment; 200, first screw hole; 300, second screw hole; 400, third screw hole; 500, lower bone fragment; 600, fourth screw hole. DETAILED DESCRIPTION

[0047] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0048] Figure 1 Taking an oblique leg fracture as an example, the upper bone fragment 100 and the lower bone fragment 500 are joined together, and screw holes are drilled and screws are inserted into the screw holes. The screw holes are not directly visible from the outside, so the first screw hole 200, the second screw hole 300, the third screw hole 400, and the fourth screw hole 600 are indicated by dotted lines.

[0049] refer to Figures 1 to 12 The present invention protects a biomedical degradable pure magnesium screw, which includes a fixing screw 1, in which a telescopic component 2 and an energy storage component 3 are provided.

[0050] The fixing screw 1 is used to connect the fracture section. The fixing screw 1 has the same function as the conventional fracture screw, which is perpendicular to the section to connect and fix the section. The main application position of the fixing screw 1 is Figure 1 The fourth screw hole 600 is located in the middle to connect the upper bone fragments 100 and the lower bone fragments 500.

[0051] The telescopic component 2 can protrude from the side of the fixing screw 1. The purpose of the telescopic component 2 protruding from the fixing screw 1 is to prevent the fixing screw 1 from spinning and to fix the cross section from different angles.

[0052] The energy storage component 3 can provide the telescopic component 2 with a force to protrude the fixing screw 1, so that the telescopic component 2 can automatically extend;

[0053] The fixing screw 1 and the telescopic assembly 2 are both made of pure magnesium with a purity of no less than 99.99 wt.%. The energy storage assembly 3 is made of a material that is absorbable by the human body. The absorbable material can be a biodegradable metal, such as pure magnesium, or a substance that can be absorbed by the human body, such as water or inorganic salts.

[0054] The present invention provides a telescopic component 2, which can protrude from the side of the fixing screw 1. The telescopic component 2 protrudes from the side and abuts against the wall of the fourth screw hole 600, that is, the bone, thereby increasing the firmness of the fixing screw 1 and preventing the fixing screw 1 from spinning. This can achieve a good fixing effect and firmly connect the cross section. By providing an energy storage component 3, the fixing screw 1 can be directly applied to the cross section, that is, Figure 1The fourth screw hole 600 in the bone fragment is located in the center of the scissor. After the two ends of the fixing screw 1 are inserted into the blind holes in the upper and lower bone fragments 100, 500, respectively, the cross-sections of the upper and lower bone fragments 100 and 500 are aligned. The energy storage assembly 3 then provides a delayed force to the telescopic assembly 2, causing it to extend, securing the fragments and preventing cross-section movement. The energy storage assembly 3 serves two purposes. The first is to drive the telescopic assembly 2 to extend. After the fixing screw 1 is placed in the fourth screw hole 600 and the cross-sections of the upper and lower bone fragments 100 and 500 are aligned, the fixing screw 1 is already inside the bone, making it impossible for the doctor to operate it from the outside. The energy storage assembly 3 acts on the doctor's behalf to drive the telescopic assembly 2 to extend, securing the fixing screw 1 securely within the fourth screw hole 600. The second is to delay the release of the driving force, ensuring that the doctor can place the fixing screw 1 in the screw hole before releasing the driving force to extend the telescopic assembly 2. Of course, the delayed release of the force by the energy storage assembly 3 is within a certain, known time range, allowing the doctor to place the fixing screw 1 within this time.

[0055] By selecting pure magnesium for the fixation screw 1 and telescopic assembly 2, magnesium is an essential element for the human body, involved in numerous physiological processes such as cellular metabolism, energy transfer, and bone mineralization. The magnesium ions released by the pure magnesium screw after degradation in the body are absorbed and utilized by the body, without causing immune rejection or other harmful physiological reactions. The elastic modulus of the pure magnesium screw is approximately 41-45 GPa, which is closer to the elastic modulus of human bone tissue (15-40 GPa). This allows for better stress transfer during fracture healing, reduces stress shielding, and avoids complications such as osteoporosis, bone resorption, and implant loosening caused by stress shielding, thereby promoting bone healing and remodeling at the fracture site.

[0056] refer to Figure 4 、 Figure 5 、 Figure 6 、 Figure 9 Figure 10 In a specific embodiment, the fixing screw 1 includes a screw body 11, a hollow cavity 16 is provided in the screw body 11, and the telescopic assembly 2 is provided in the hollow cavity 16. The axis of the hollow cavity 16 coincides with the axis of the screw body 11.

[0057] The screw body 11 also includes a telescopic channel 17, which is radially disposed within the sidewall of the screw body 11 and communicates with the hollow cavity 16, allowing the telescopic assembly 2 to extend from the channel 17. Specifically, the telescopic channel 17 is disposed within the sidewall between the hollow cavity 16 and the outer surface of the screw body 11. The axis of the telescopic channel 17 is perpendicular to the axis of the hollow cavity 16.

[0058] By providing the telescopic channel 17 , part of the telescopic assembly 2 can be extended along the radial direction of the screw body 11 . The extended part of the telescopic assembly 2 abuts against the wall of the screw hole to prevent the screw body 11 from spinning.

[0059] refer to Figure 4 or Figure 9 In a specific embodiment, a plurality of strip-shaped cavities 12 are provided in the side wall of the screw body 11, and the plurality of strip-shaped cavities 12 are distributed along the circumferential direction; each strip-shaped cavity 12 is a closed cavity extending along the vertical direction.

[0060] The provision of the strip-shaped cavity 12 in this embodiment has three functions. The first function is to reduce the elastic modulus of the screw body 11. The elastic modulus of a pure magnesium screw is about 41~45GPa. Although it is close to the elastic modulus of 15~40GPa of human bone tissue, it is still higher than the elastic modulus of human cancellous bone. By providing multiple strip-shaped cavities 12, the elastic modulus of the screw body 11 can be effectively reduced, so that the elastic modulus of the screw body 11 is close to the elastic modulus of human bone tissue, which is beneficial to the recovery of the fracture position. The second function is to enhance the stability of fixation. Existing pure magnesium screws loosen during the degradation process. In this embodiment, by providing the strip-shaped cavity 12, after the outer surface of the screw body 11 degrades, a hollow structure is formed at the strip-shaped cavity 12, and the surrounding bone tissue gradually grows into the hollow structure, which can further enhance the bonding force between the screw and the bone tissue and improve the long-term stability of the fixation. The third function is to promote bone tissue growth. Strip-shaped cavity 12 provides more space and channels for bone tissue to grow in, facilitating the migration, proliferation, and differentiation of surrounding bone cells. This accelerates bone tissue growth on and within screw body 11, allowing screw body 11 to better fuse with bone tissue, forming a stronger bone-screw complex and promoting fracture healing. Furthermore, certain ions or products released during the degradation process of the biodegradable material, such as magnesium ions and an alkaline microenvironment, may stimulate bone cell activity and promote bone formation.

[0061] In one specific embodiment, individual strip-shaped cavities 12 are filled with bone support material. A degradable porous composite scaffold material for bone transplantation, with application number 201610025098.5, can be added. This material has a natural bone mineral three-dimensional interconnected mesh microstructure and good mechanical strength. Whiskers with a large aspect ratio grow within the mesh, increasing the material's specific surface area, allowing for relatively adjustable micropore diameters and improved cell adhesion. It also has good degradability, enabling better recovery of the fracture site. A degradable porous scaffold material for guided bone tissue regeneration and repair, with application number 200810058677.5, can also be added. This material is a multifunctional material that promotes and induces bone tissue repair, is antibacterial, and has an adjustable degradation rate in vivo. This material can be configured to adjust degradation rates according to different stages of bone recovery, providing both support and a certain degradation rate. A drug-loaded bone repair internal fixation material, with application number 202110785442.1, can also be added. This material can achieve sustained release of drugs without affecting the morphology and properties of the material.

[0062] refer to Figure 4 、 Figure 5 、 Figure 7 、 Figure 9 or Figure 10 In one embodiment, adjacent strip-shaped cavities 12 are connected by connecting channels 13. The provision of connecting channels 13 increases connectivity between adjacent strip-shaped cavities 12, increases the irregularity of the hollow structure, and allows bone tissue to grow into the connecting channels 13, thereby increasing firmness.

[0063] refer to Figure 2 、 Figure 5 、 Figure 6 or Figure 10 In a specific embodiment, the side wall surface of the screw body 11 is provided with a protrusion 14, and the protrusion 14 forms an external thread. The position of the external thread is set according to actual needs. Figure 2 For example, the external thread can be provided at the bottom of the screw body 11, and the top of the screw body 11 is not provided with a thread. In this way, when the screw body 11 is placed at the position of the fourth screw hole 600, the bottom end of the screw body 11 can be screwed into one side section, the top end of the screw body 11 can be inserted into the other side section, and then the telescopic component 2 is extended to fix it. Of course, the external thread can also be provided on the entire side of the screw body 11, and can be provided more densely or more sparsely according to actual needs. A straight groove 19 is provided on the top surface of the screw body 11. The purpose of the straight groove 19 is to screw the screw body 11 so that the screw body 11 can enter the screw hole.

[0064] In this embodiment, by arranging the protrusions 14 at different positions, different thread forms are formed, which can be applied to fracture sections at different positions and in different states, making the screw fixation more secure.

[0065] refer to Figure 4 、 Figure 5 、 Figure 9 or Figure 11 In one embodiment, the telescopic assembly 2 includes a rotatable rotating rod 21 and a slider 22 mounted on the rotating rod 21. The slider 22 can move along the axial direction of the rotating rod 21. The rotating rod 21 is composed of a cylindrical top block and a screw-shaped rod body. The rod body is an externally threaded rod, and the slider 22 has an internally threaded hole. Rotation of the rotating rod 21 can drive the slider 22 to rise or fall.

[0066] The slider 22 is hinged to one end of the connecting rod 23, and the other end of the connecting rod 23 is hinged to the fixing block 24. Figure 11 , the connecting rod 23 can move slightly in the vertical direction and lock in the horizontal direction to achieve hinged connection. In this way, it can be ensured that the slider 22 can pull or push the fixed block 24 when moving in the vertical direction. Among them, the fixed block 24 is composed of a cylindrical body and a conical fixed end to form a bullet-shaped shape. The cylindrical body is connected to the connecting rod 23, and the fixed end can protrude from the screw body 11. The conical fixed end can abut against the wall of the screw hole, so that the screw body 11 is firmly set in the screw hole to prevent the screw body 11 from spinning.

[0067] The rotating rod 21 is provided with a latching member, and the energy storage assembly 3 can engage with the latching member to drive the rotating rod 21 to rotate. In this embodiment, the provision of the latching member enables the energy storage assembly 3 to transmit force to the rotating rod 21, thereby rotating the rotating rod 21, and in turn causing the slider 22 to push the fixing block 24 out of the screw body 11.

[0068] refer to Figure 9 and Figure 10 In a specific embodiment, a top groove 18 is provided on the top surface of the screw body 11 , and the top groove 18 is used to accommodate the top block of the rotating rod 21 and the energy storage assembly 3 .

[0069] A bottom groove 15 is provided on the bottom surface of the hollow cavity 16. The inner wall of the bottom groove 15 is smooth. The bottom groove 15 is used to accommodate the bottom end of the rotating rod 21 so that the rotating rod 21 can rotate relative to the bottom groove 15. In this way, the rotating rod 21 can stably rotate around its own axis without the rotating rod 21 itself rising or falling. Figure 10, the hollow cavity 16 includes a central cavity 161 and a side cavity 162. Among them, the axis of the central cavity 161 coincides with the axis of the screw body 11. The side cavity 162 is opened on the side wall of the central cavity 161. The side cavity 162 is set to accommodate the fixed block 24, so that the fixed block 24 can be fitted in the side cavity 162 when it retracts; secondly, it is for limiting. When the fixed block 24 is extended, the side cavity 162 can assist in limiting the extension trajectory of the fixed block 24, so that the fixed block 24 can be accurately extended from the telescopic channel 17. Since the movement amplitude of the fixed block 24 is large, in order to ensure that the fixed block 24 can be extended smoothly, a chamfer is set at one end of the telescopic channel 17 close to the hollow cavity 16.

[0070] refer to Figure 11 In one embodiment, a notch 211 is provided on the top sidewall of the rotating rod 21, and the engaging member is the notch 211. Specifically, the notch 211 is provided on the sidewall of the top block of the rotating rod 21. Providing the notch 211 on the sidewall of the top block facilitates direct conversion of the force provided by the energy storage assembly 3 into a tangential force, enabling the rotating rod 21 to rotate and the slider 22 to rise, thereby pushing the fixed block 24 out of the telescopic channel 17.

[0071] The top surface of the rotating rod 21 is provided with a transverse groove 212. The transverse groove 212 has two functions. The first function is to be able to manually apply external force to extend the fixed block 24. For example, Figure 1 In this embodiment, clockwise rotation of the rotating rod 21 extends the fixed block 24, while counterclockwise rotation retracts it. When the fixing screw 1 is placed in the first screw hole 200, a clockwise rotational force can be manually applied through the transverse groove 212 to extend the fixed block 24. A second function is to store energy in the energy storage assembly 3. Counterclockwise rotation of the rotating rod 21 stores energy in the energy storage assembly 3. Once the fixing screw 1 enters the human body, the force is released, causing the rotating rod 21 to rotate clockwise.

[0072] refer to Figure 2 and Figure 12 In one embodiment, the energy storage assembly 3 includes an elastic member and a base 32. One end of the elastic member is fixed to the fixing screw 1, and the other end of the elastic member is a free end that can engage with the engaging member. Specifically, one end of the elastic member is fixed to the side wall of the top groove 18, and the free end of the elastic member is connected to the notch 211.

[0073] The elastic member can be deformed and can be a shrapnel, a spring, a spring, etc.

[0074] The base 32 can fix the deformed elastic member. The base 32 can be an ice cube. First, pull the free end of the elastic member to deform the elastic member to store energy, then soak the deformed elastic member in liquid water and freeze it to form an ice cube as the base 32. At this time, the elastic member is also fixed.

[0075] After the ice cubes are absorbed, the elastic member releases its force, pulling the rotating rod 21 to rotate.

[0076] This embodiment utilizes an elastic member to facilitate energy storage, resulting in high stability and a low failure rate. By providing a base 32, the elastic member can be positioned in any desired position for fixation, allowing energy storage to be tailored to the actual fracture situation, thereby completing the extension of the fixing member 24.

[0077] refer to Figure 12 In one embodiment, the elastic member is a spring 31 having a hook 311 at its free end. The spring 31 is made of pure magnesium with a purity of not less than 99.99 wt.%. The spring 31 can be of different lengths and widths depending on actual needs.

[0078] The advantage of providing a spring 31 in this embodiment is that it is disc-shaped and its elastic force is directed circumferentially, facilitating rotation of the rotating rod 21. One end of the spring 31 is fixed to the inner wall of the top groove 18, and rotating the free end of the spring 31 can store energy.

[0079] refer to Figure 9 、 Figure 10 and Figure 12 In a specific embodiment, the base 32 is preferably an ice cube. The ice cube is an ice cube frozen from sterile physiological saline. In actual use, the hook 311 of the mainspring 31 is engaged with the notch 211. Then, the rotating rod 21 is twisted with a screwdriver to pull the mainspring 31 to store energy, and the screwdriver is fixed externally. Finally, physiological saline is poured into the top groove 18 and frozen in a sterile environment to form an ice cube. The ice cube serves as the base 32, and the ice cube can fix the mainspring 31 well. After the base 32 is removed, the screwdriver is removed, and the fixing screw 1 can be used for the fracture site.

[0080] Of course, it should be noted that, considering the energy loss, the extension length of the fixing block 24 is set to a margin, for example, Figure 9 When the middle spring 31 is not charged, the fixing block 24 is fully extended. When the spring 31 is charged and then released, the fixing block 24 can be extended a little bit to contact the bone. Figure 9 For example, assuming that the fully extended length of the fixing block 24 is 20 mm, after the screwdriver turns the rotating rod 21, pulls the mainspring 31 to store energy, and then releases it, the extended length of the fixing block 24 may be 12 mm, and it can still function in this case. Therefore, this embodiment is feasible.

[0081] In addition, the hook 311 and the notch 211 are detachably connected. The hook 311 can be separated from the notch 211 first, and then the rotating rod 21 can be twisted to make the fixing block 24 extend from the side wall of the screw body 11. Finally, the hook 311 can be connected to the notch 211 to form a fixed ice base.

[0082] The diameter of the top block of the rotating rod 21 is the same as the inner diameter of the hollow cavity 16 or the diameter of the top block of the rotating rod 21 is slightly smaller than the inner diameter of the hollow cavity 16. In this way, physiological saline does not enter or only partially enters the hollow cavity 16, and auxiliary fixation is achieved after being frozen into ice cubes.

[0083] The ice base 32 in this embodiment serves a purpose, as it provides a strong holding force, effectively securing the spring 31. After the fixing screw 1 is placed in the fracture site, the body's heat melts the ice, releasing the elastic force of the spring 31 and rotating the rotating rod 21. Ice melts quickly and is harmless to the human body. Furthermore, the melting of the ice delays the release of the elastic force of the spring 31. Furthermore, the melting time of a specific volume of ice is within a measurable range. This allows the doctor to position the fixing screw 1 based on the melting time to prevent premature extension of the telescopic assembly 2.

[0084] Considering the potential for corrosion when water comes into contact with the magnesium screw body 11, a waterproof layer can be provided on the inner surface of the top groove 18. This waterproof layer prevents or reduces direct water contact with the magnesium screw body 11. The waterproof layer can be made of polylactic acid (PLA) or polyglycolic acid (PGA). PLA is a biodegradable thermoplastic polyester. In the natural environment or in the human body, PLA gradually degrades into carbon dioxide and water through hydrolysis and enzymatic degradation, ultimately being metabolized, absorbed, or excreted by the body. Unlike traditional plastics, PLA does not cause long-term environmental pollution or residual residues in the body. PGA has excellent biodegradability. It undergoes enzymatic or hydrolytic degradation in the body into carbon dioxide and water, ultimately excreting the substance. This leaves no long-term harmful residues in the environment or the human body, making it highly advantageous in the biomedical and environmental fields.

[0085] The fixing screw 1 of the present invention can be applied to multiple positions. Figure 1 For example, the fixing screw 1 can be set at the position of the fourth screw hole 600. In this way, the energy storage component 2 needs to store energy. After the fixing screw 1 is placed at the position of the fourth screw hole 600, the fixing block 24 can be extended with a delay to prevent the fixing screw 1 from rotating, so that the fixing screw 1 firmly connects the upper bone fragment 100 and the lower bone fragment 500. Of course, the fixing screw 1 can also be set at the position of the first screw hole 200 in the figure like an ordinary screw. In this case, there is no need for the energy storage component 3 to store energy. First, the fixing screw 1 is screwed into the bone, and then the rotating rod 21 is turned through the transverse groove 212 to extend the fixing block 24 to prevent rotation.

[0086] The above disclosure is merely a preferred embodiment of the present invention and certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A biomedical degradable pure magnesium screw, characterized in that: It comprises a fixing screw (1), wherein a telescopic component (2) and an energy storage component (3) are provided inside the fixing screw (1); The fixing screw (1) is used to connect the fractured sections; The telescopic assembly (2) can protrude from the side of the fixing screw (1); The energy storage component (3) can provide the telescopic component (2) with a force that delays the protrusion of the fixing screw (1), so that the telescopic component (2) can automatically extend; The fixing screw (1) and the telescopic component (2) are both made of pure magnesium with a purity of not less than 99.99 wt.%; the energy storage component (3) is made of elastic material that can be absorbed by the human body; The fixing screw (1) comprises a screw body (11), a hollow cavity (16) is provided in the screw body (11), and the telescopic assembly (2) is arranged in the hollow cavity (16); A telescopic channel (17) is further provided in the screw body (11), the telescopic channel (17) being radially arranged in the side wall of the screw body (11), the telescopic channel (17) being in communication with the hollow cavity (16), so that the telescopic assembly (2) can be extended from the telescopic channel (17); The telescopic assembly (2) comprises a rotatable rotating rod (21) and a slider (22) sleeved on the rotating rod (21), wherein the slider (22) is movable along the axial direction of the rotating rod (21); The slider (22) is hinged to one end of the connecting rod (23), and the other end of the connecting rod (23) is hinged to the fixed block (24); The rotating rod (21) is provided with a snap-fitting piece, and the energy storage assembly (3) can snap-fit ​​with the snap-fitting piece to drive the rotating rod (21) to rotate; A notch (211) is provided on the top side wall of the rotating rod (21), and the engaging member is the notch (211); A transverse groove (212) is provided on the top surface of the rotating rod (21); The energy storage component (3) comprises an elastic member and a base (32), one end of the elastic member is fixed to the fixing screw (1), and the other end of the elastic member is a free end, and the free end can be engaged with the engaging member; The elastic member can be deformed; The base (32) can fix the deformed elastic member.

2. The biomedical degradable pure magnesium screw according to claim 1, characterized in that: A plurality of strip-shaped cavities (12) are provided in the side wall of the screw body (11), and the plurality of strip-shaped cavities (12) are distributed along the circumferential direction; Each of the strip-shaped cavities (12) is a closed cavity extending in a vertical direction.

3. The biomedical degradable pure magnesium screw according to claim 2, characterized in that: Adjacent strip-shaped cavities (12) are connected via connecting channels (13).

4. The biomedical degradable pure magnesium screw according to claim 1, characterized in that: A protrusion (14) is provided on the side wall surface of the screw body (11), and the protrusion (14) forms an external thread; A slot (19) is provided on the top surface of the screw body (11).

5. The biomedical degradable pure magnesium screw according to claim 1, characterized in that: The elastic member is a spring (31), and a hook (311) is provided on the free end of the spring (31); the spring (31) is made of pure magnesium with a purity of not less than 99.99 wt.%.

6. The biomedical degradable pure magnesium screw according to claim 1, characterized in that: The base (32) is an ice cube.

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