Spinal fixation pegs and spinal fixation devices
By using external thread fixation and dynamic adjustment of bioadjustable materials in the spinal fixation device, the problem that traditional devices cannot meet the dynamic needs of bone healing is solved, achieving stable support and adaptive adjustment during the bone healing process and promoting bone recovery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANXI MEDICAL UNIV
- Filing Date
- 2025-03-14
- Publication Date
- 2026-08-04
AI Technical Summary
Traditional spinal fixation devices cannot accurately meet the needs of dynamic changes during bone healing. Insufficient strength in the early stages can easily lead to poor healing, and lack of elasticity in the later stages can affect bone growth and recovery.
The screw is fixed by external threads on the outer surface of the screw sleeve, and a bio-adjustable material is injected into the pore network inside the screw shaft. It is activated and cured by an external light source to achieve dynamic adjustment of the elastic modulus of the screw shaft, so as to adapt to the high strength in the early stage of bone healing and the elastic adaptation in the later stage.
During the bone healing process, it provides initial stable support, adapts to bone growth and micro-movements in the later stages, promotes normal bone healing and recovery, and reduces adverse stimuli.
Smart Images
Figure CN224584832U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to spinal fixation devices, and in particular to spinal fixation nails and spinal fixation devices, belonging to the field of medical device technology. Background Technology
[0002] In the field of spinal surgery, the treatment of spinal injuries and diseases has always been a key focus and challenge. Bone healing is a crucial aspect of spinal treatment; however, traditional spinal fixation devices have many limitations in adapting to the bone healing process. Situations such as spinal fractures and scoliosis correction surgery require stable fixation to support bone tissue healing and recovery. However, in the early stages of bone healing, extremely high fixation strength is needed to maintain spinal stability and prevent displacement and further injury. As the healing process progresses, a certain degree of elasticity is required to accommodate bone growth and remodeling; excessive rigid fixation may actually hinder normal healing.
[0003] Existing fixation devices often fail to precisely meet the needs of this dynamic change. They may not provide sufficient strength in the early stages, increasing the risk of poor healing, or they may hinder the natural growth and recovery of the bone in the later stages due to a lack of elastic adaptation, resulting in unsatisfactory treatment outcomes and even complications.
[0004] Therefore, it is urgent to improve the spinal fixation nails and spinal fixation devices to solve the aforementioned problems. Summary of the Invention
[0005] The purpose of this invention is to provide a spinal fixation nail and a spinal fixation device. The external threads on the outer surface of the nail sleeve help to firmly fix the entire device to the spine. The nail rod is inserted into the cavity of the nail sleeve and connected by a positioning pin to form an integral structure. During surgery, a bio-adjustable material is injected into the pore network through the filling channel inside the nail rod, and then activated and cured using an external light source. The cured bio-adjustable material changes the physical structure of the nail rod. Due to the gradient change in porosity along the axial direction of the nail rod and the pore network penetrating the outer wall of the nail sleeve, the overall elastic modulus of the nail rod can be dynamically adjusted as needed. The gradient pore structure and adjustable elastic modulus of the nail rod can adapt to the high strength requirements in the early stage of bone healing and the elastic adaptation requirements in the later stage, promoting normal bone healing and recovery.
[0006] To achieve the above objectives, the main technical solutions adopted by this utility model include: A spinal fixation screw and spinal fixation device, comprising a screw rod, a screw sleeve, and a positioning pin, wherein the screw rod is made of carbon fiber, the screw sleeve is made of titanium alloy, the outer surface of the screw sleeve has external threads, the inside of the screw sleeve has a cavity, one end of the screw rod is inserted into the cavity and connected by the positioning pin, the main body of the screw rod is a porous carbon fiber structure with variable porosity, the inside of the screw rod has an axially distributed pore network, the porosity varies along the axial gradient of the screw rod, and the pore network penetrates the outer wall of the screw sleeve; The nail has a filling channel inside, which extends through the end of the nail and connects to a pore network, wherein the pore network contains a bio-adjustable material for intraoperative injection. The bio-tunable material includes photocurable hydrogel and biodegradable polymer. After being injected into the pore network, the bio-tunable material is activated and cured by an external light source, dynamically adjusting the overall elastic modulus of the nail rod.
[0007] Preferably, the porosity of the pore network near the upper end of the nail bar is lower than that at the distal end, forming a gradient pore structure to adapt to the high strength requirements in the early stage of bone healing and the elastic adaptation requirements in the later stage.
[0008] Preferably, the feed end of the filling channel is provided with a sealing cap, which is threadedly connected to the nail rod to prevent leakage of the bio-adjustable material. The nail rod has multiple screw grooves on its surface near the sealing cap, and the upper surface of the sealing cap has an internal hexagonal groove. The side of the sealing cap near the internal hexagonal groove is provided with a reserved light guide window for an external light source to activate the photocurable hydrogel through the reserved light guide window.
[0009] Preferably, an annular groove is provided at the connection between the nail sleeve and the nail rod, and an elastic sealing ring is embedded in the annular groove to prevent the bio-adjustable material from seeping into the contact interface between the nail sleeve and the nail rod.
[0010] Preferably, the biotunable material further contains bone growth factors and antibacterial components, and after curing, it has both mechanical adaptability and bioactivity.
[0011] Preferably, a screw seat is rotatably connected to the upper end of the nail rod, and a nail head is threadedly connected inside the screw seat. A hole is formed on the upper surface of the nail head, the hole penetrates the nail head, and the hole corresponds to the reserved light guide window. An internal hexagonal groove is formed on the side of the nail head near the hole.
[0012] Preferably, the spinal fixation device includes at least two spinal fixation nails and a detachably connected rod. The rod is made of carbon fiber composite material, with both ends of the rod penetrating the interior of the screw seat and the rod abutting against the inner wall of the screw head. The surface of the rod has an interface corresponding to the filling channel, through which the bioadjustable material is injected into the filling channel during the operation.
[0013] This utility model has at least the following beneficial effects: 1. In this spinal fixation device, the external threads on the outer surface of the screw sleeve help to firmly fix the entire device to the spine. The screw rod is inserted into the cavity of the screw sleeve and connected by a locating pin to form a unified structure. During surgery, a bio-adjustable material is injected into the porous network through the filling channels inside the screw rod, and then activated and cured using an external light source. The cured bio-adjustable material alters the physical structure of the screw rod. Due to the gradient change in porosity along the screw rod axis and the porous network penetrating the outer wall of the screw sleeve, the overall elastic modulus of the screw rod can be dynamically adjusted as needed. The gradient porosity structure and adjustable elastic modulus of the screw rod can adapt to the high strength requirements in the early stages of bone healing and the elastic adaptation requirements in the later stages, promoting normal bone healing and recovery.
[0014] 2. During bone healing, the gradient porosity of the screw rod plays a crucial role. In the early stages of healing, the low porosity and high strength of the upper end of the screw rod provide stable support to the fracture site, resisting external stress and load, and preventing displacement and deformation of the fracture ends. As time progresses and the bone begins to heal, the high porosity and elasticity of the distal end of the screw rod begin to play a role. During natural bone growth and micro-movement, the distal end of the screw rod can produce appropriate deformation, buffering and adapting to these changes, reducing excessive restriction and adverse stimulation to the healing bone. 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: Figure 1 This is a schematic diagram of the isometric structure provided by this utility model; Figure 2 This is a schematic diagram of the overall dissection of the present invention; Figure 3 Provided by this utility model Figure 2 A magnified schematic diagram of the structure at point A in the middle; Figure 4 This is a partially exploded view of the present invention; Figure 5 Provided by this utility model Figure 4A magnified schematic diagram of the structure at point B in the middle; Figure 6 This is a schematic diagram of the internal decomposition of the biotunable material provided by this utility model.
[0016] In the diagram, 1. Screw; 2. Screw sleeve; 3. External thread; 4. Cavity; 5. Locating pin; 6. Pore network; 7. Filling channel; 8. Bio-adjustable material; 9. Photocurable hydrogel; 10. Biodegradable polymer; 31. Sealing cap; 32. Screw slot; 33. Hexagonal socket one; 34. Reserved light guide window; 41. Annular slot; 42. Elastic sealing ring; 51. Bone growth factor; 52. Antibacterial component; 61. Screw seat; 62. Screw head; 63. Hole; 64. Hexagonal socket two; 71. Rod body; 72. Interface. Detailed Implementation
[0017] The following will describe in detail the implementation of this application with reference to the accompanying drawings and embodiments, so that the implementation process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0018] like Figure 1 - Figure 6 As shown, the spinal fixation nail and spinal fixation device provided in this embodiment include a nail rod 1, a nail sleeve 2, and a positioning pin 5. The nail rod 1 is made of carbon fiber and mainly serves to fix the spine. Carbon fiber has the characteristics of high strength and light weight, which can reduce the burden of foreign bodies in the patient's body while ensuring fixation strength. In addition, carbon fiber has good chemical stability and high compatibility with human tissue, reducing the risk of rejection reaction. The nail sleeve 2 is made of titanium alloy and has external threads 3 on its outer surface. The nail sleeve 2 provides external fixation and connection, and the external threads 3 on the outer surface help to enhance the fixation effect. The titanium alloy material ensures strength and stability. At the same time, titanium alloy has excellent strength and corrosion resistance, ensuring the long-term stability of the fixation nail in the body. Its good biocompatibility makes it... It is designed to minimize adverse reactions when in contact with human tissue. The internal cavity 4 of the nail sleeve 2 is provided, and one end of the nail rod 1 is inserted into the cavity 4 and connected by a positioning pin 5. The positioning pin 5 is used to connect the nail rod 1 and the nail sleeve 2 to ensure a firm connection between the two. The main body of the nail rod 1 is a porous carbon fiber structure with variable porosity. The nail rod 1 has many pores inside, and the porosity is not uniform but gradually changes along the axial direction of the nail rod 1. The internal cavity of the nail rod 1 has an axially distributed pore network 6, and the porosity changes gradually along the axial direction of the nail rod 1. The pore network 6 penetrates the outer wall of the nail sleeve 2 and allows the injection of biotunable material 8. This allows the biotunable material 8 to be injected from the inside of the nail rod 1 into the outside of the nail sleeve 2, changing the mechanical properties of the nail rod 1 to adapt to the bone healing needs at different stages. The nail 1 has a filling channel 7 inside, which extends through the end of the nail 1 and connects to the pore network 6. The pore network 6 contains a bio-adjustable material 8 for intraoperative injection. The nail 1 also has at least one filling channel 7 inside, which extends from the end of the nail 1 to the pore network 6. This channel facilitates the injection of a bio-adjustable material 8, such as a photocurable hydrogel 9 or a biodegradable polymer 10, into the pore network 6 during surgery. The biotunable material 8 includes a photocurable hydrogel 9 and a biodegradable polymer 10. After being injected into the porous network 6, the biotunable material 8 is activated and cured by an external light source, dynamically adjusting the overall elastic modulus of the screw rod 1. During the operation, the biotunable material 8 is injected into the porous network 6 through the filling channel 7, and then cured by an external light source. The cured material fills the porous network 6, changing the physical structure of the screw rod 1, thereby dynamically adjusting the overall elastic modulus of the screw rod 1. The photocurable hydrogel 9 has the characteristic of being able to cure under irradiation with light of a specific wavelength. After curing, it can provide a certain degree of support and elasticity adjustment. The biodegradable polymer 10 can gradually degrade in vivo, providing space for tissue growth, and can also have a certain regulatory effect on the mechanical properties of the screw rod 1 during the degradation process. The biotunable material 8 also contains bone growth factor 51 and antibacterial component 52. After curing, it has both mechanical adaptation and bioactivity functions. Bone growth factor 51 stimulates the proliferation and differentiation of osteoblasts, promoting bone growth and repair, while antibacterial component 52 inhibits the growth and reproduction of bacteria, reducing the risk of infection.
[0019] Among them, such as Figure 1 - Figure 6 As shown, the porosity of the pore network 6 near the upper end of the nail rod 1 is lower than that at the distal end, forming a gradient pore structure to meet the high strength requirements in the early stage of bone healing and the elastic adaptation requirements in the later stage. The pore network 6 is an internal structure of the nail rod 1, and the difference in its porosity distribution affects the mechanical properties of different parts of the nail rod 1. The lower porosity at the upper end of the nail rod 1 results in a relatively larger solid part and a more compact material structure, thus ensuring high strength in this part. The higher porosity at the distal end of the nail rod 1 results in a relatively loose material structure in this part. This loose structure can produce a certain deformation while bearing a certain stress, thus providing better elasticity for this part. In the later stage of bone healing, as the bone gradually heals and recovers, a certain degree of elasticity is needed to adapt to the natural growth and micro-movement of the bone.
[0020] Among them, such as Figure 1 - Figure 6As shown, the feed end of the filling channel 7 is provided with a sealing cap 31. The sealing cap 31 is threadedly connected to the nail rod 1. The sealing cap 31 seals the filling channel 7 to prevent leakage of the bio-adjustable material 8. The nail rod 1 has multiple screw slots 32 on its surface near the sealing cap 31. The nail rod 1 can be rotated by tools through the screw slots 32. The upper surface of the sealing cap 31 has an internal hexagonal groove 33. The internal hexagonal groove 33 facilitates the installation or removal of the sealing cap 31 using tools. The side of the sealing cap 31 near the internal hexagonal groove 33 has a reserved light guide window 34. The reserved light guide window 34 allows external light sources to pass through, which is used to activate the photocurable hydrogel 9 through the reserved light guide window 34.
[0021] Among them, such as Figure 1 - Figure 6 As shown, an annular groove 41 is provided at the connection between the nail sleeve 2 and the nail rod 1. An elastic sealing ring 42 is embedded in the annular groove 41. The annular groove 41 provides an installation position for the elastic sealing ring 42. The elastic sealing ring 42 plays a sealing role to prevent the bio-adjustable material 8 from seeping into the contact interface between the nail sleeve 2 and the nail rod 1.
[0022] Among them, such as Figure 1 - Figure 6 As shown, a screw seat 61 is rotatably connected to the upper end of the nail rod 1. A nail head 62 is threaded inside the screw seat 61. The screw seat 61 is used to connect the nail rod 1 and the nail head 62 to achieve a rotatable connection, providing a certain degree of flexibility and angle adjustment. A hole 63 is opened on the upper surface of the nail head 62. The hole 63 penetrates the nail head 62 and corresponds to the reserved light guide window 34. The hole 63 and the reserved light guide window 34 correspond to ensure that the external light source can pass through, thereby activating the photocurable hydrogel 9. An internal hexagonal groove 64 is opened on the side of the nail head 62 near the hole 63. The internal hexagonal groove 64 facilitates the installation and removal of the nail head 62 using tools.
[0023] Among them, such as Figure 1 - Figure 6 As shown, the spinal fixation device includes at least two fixation nails and a detachably connected rod 71. The rod 71 is made of carbon fiber composite material. Both ends of the rod 71 penetrate the interior of the screw seat 61, and the rod 71 abuts against the inner wall of the nail head 62. The surface of the rod 71 has an interface 72 corresponding to the filling channel 7. During the operation, bio-adjustable material 8 is injected into the filling channel 7 through the interface 72. The spinal fixation nails are used to fix the spine, providing support and stability. The rod 71 is placed inside the screw seat 61 and fixed by the nail head 62, achieving the effect of connecting multiple fixation nails and enhancing the overall fixation effect. Its carbon fiber composite material provides sufficient strength and stability. The interface 72 corresponds to the filling channel 7 of the fixation nail and serves as a channel for injecting the bio-adjustable material 8.
[0024] like Figure 1 - Figure 6 As shown, the principle of the spinal fixation nail and spinal fixation device provided in this embodiment is as follows: Before surgery, select appropriate specifications and quantities of spinal fixation nails and rods 71. Insert one end of the nail rod 1 into the cavity 4 of the nail sleeve 2 and connect and fix it with a positioning pin 5. Ensure that the elastic sealing ring 42 in the annular groove 41 at the connection between the nail sleeve 2 and the nail rod 1 is installed in place. Rotate the nail rod 1 with the help of a tool and screw groove 32 to drive the nail sleeve 2 to rotate, and fix the nail sleeve 2 of the spinal fixation nail to the corresponding position of the spine through the external thread 3 on its outer surface. The feed is fed into the filling channel 7 through the feed end. Bio-adjustable material 8 is injected into the porous network 6 of the nail rod 1. After injection, it is sealed with a threaded connection using a sealing cap 31. After installing at least two fixing nails, the rod body 71 is placed in the screw seat 61, so that the interface 72 on the surface of the rod body 71 corresponds to the filling channel 7. Then, the rod body 71 is fixed by the nail head 62, and the hole 63 on the nail head 62 corresponds to the reserved light guide window 34. An external light source is used to activate the photocurable hydrogel 9 through the reserved light guide window 34 and the hole 63, so that it is cured and the overall elastic modulus of the nail rod 1 is dynamically adjusted.
[0025] If certain terms are used in the specification and claims to refer to specific components, those skilled in the art will understand that hardware manufacturers may use different names to refer to the same component. This specification and claims do not distinguish components based on differences in name, but rather on differences in function. The term "comprising" as used throughout the specification and claims is an open-ended term and should be interpreted as "comprising but not limited to." "Approximately" means that within an acceptable margin of error, those skilled in the art can solve the technical problem and substantially achieve the technical effect within a certain margin of error.
[0026] It should be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a product or system comprising a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a product or system. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the product or system that includes that element.
[0027] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.
Claims
1. A spinal fixation nail, comprising a nail rod (1), a nail sleeve (2), and a positioning pin (5), characterized in that: The nail rod (1) is made of carbon fiber, the nail sleeve (2) is made of titanium alloy, the outer surface of the nail sleeve (2) is provided with external threads (3), the inside of the nail sleeve (2) is provided with a cavity (4), one end of the nail rod (1) is inserted into the cavity (4) and connected by a positioning pin (5), the main body of the nail rod (1) is a porous carbon fiber structure with variable porosity, the inside of the nail rod (1) is provided with an axially distributed pore network (6), the porosity changes along the axial gradient of the nail rod (1), and the pore network (6) penetrates the outer wall of the nail sleeve (2); The nail rod (1) has a filling channel (7) inside, which passes through the end of the nail rod (1) and connects to the pore network (6), wherein the pore network (6) contains a bio-adjustable material (8) for intraoperative injection. The bio-tunable material (8) includes a photocurable hydrogel (9) and a biodegradable polymer (10). After the bio-tunable material (8) is injected into the porous network (6), it is activated and cured by an external light source to dynamically adjust the overall elastic modulus of the nail rod (1).
2. The spinal fixation nail according to claim 1, characterized in that: The porosity of the pore network (6) near the upper end of the nail rod (1) is lower than that at the distal end, forming a gradient pore structure to meet the high strength requirements in the early stage of bone healing and the elastic adaptation requirements in the later stage.
3. The spinal fixation nail according to claim 1, characterized in that: The filling channel (7) has a sealing cap (31) at the feed end. The sealing cap (31) is threaded to the nail rod (1) to prevent the leakage of the bio-adjustable material (8). The nail rod (1) has multiple screw grooves (32) on its surface near the sealing cap (31). The upper surface of the sealing cap (31) has an internal hexagonal groove (33). The sealing cap (31) has a reserved light guide window (34) on its side near the internal hexagonal groove (33) for an external light source to activate the photocurable hydrogel (9) through the reserved light guide window (34).
4. The spinal fixation nail according to claim 1, characterized in that: An annular groove (41) is provided at the connection between the nail sleeve (2) and the nail rod (1). An elastic sealing ring (42) is embedded in the annular groove (41) to prevent the bio-adjustable material (8) from seeping into the contact interface between the nail sleeve (2) and the nail rod (1).
5. The spinal fixation nail according to claim 1, characterized in that: The biotunable material (8) also contains bone growth factor (51) and antibacterial component (52), and after curing, it has both mechanical adaptation and bioactivity functions.
6. The spinal fixation nail according to claim 3, characterized in that: The upper end of the nail rod (1) is rotatably connected to a screw seat (61), and the screw seat (61) is internally threaded with a nail head (62). A hole (63) is opened on the upper surface of the nail head (62), the hole (63) penetrates the nail head (62), and the hole (63) corresponds to the reserved light guide window (34). An internal hexagonal groove (64) is opened on the side of the nail head (62) near the hole (63).
7. A spinal fixation device, employing a spinal fixation nail as described in any one of claims 1-6, comprising at least two spinal fixation nails and a detachably connected rod (71), wherein the rod (71) is made of carbon fiber composite material, both ends of the rod (71) penetrate the interior of the screw seat (61), and the rod (71) abuts against the inner wall of the nail head (62), and the surface of the rod (71) is provided with an interface (72) corresponding to the filling channel (7), wherein the bioadjustable material (8) is injected into the filling channel (7) through the interface (72) during the operation.