A bone anchor implantation device

Abstract

The present application relates to medical devices, and discloses a bone anchor implant device, which forms a radially flared petaloid structure at the distal end of the anchor body, and is driven by the expansion drive shaft to rotate and achieve threaded transmission with the anchor body, thereby driving the petaloid structure to radially expand and anchor the anchor in the bone; the detachable connection design of the implant assembly and the anchor body allows the device to be separated from the anchor after expansion and locking, the drive mechanism is arranged on the implant assembly and can directly drive the expansion drive shaft to rotate, and the implant assembly is used to realize multiple steps such as positioning, implanting and expansion locking, thereby reducing the replacement of instruments and repeated alignment operations, reducing the operation complexity, shortening the operation time and improving the operation efficiency. The bone anchor implant device can ensure the stability of the bone anchor implant fixation, effectively improve the operation efficiency and implanting precision, thereby reducing the intraoperative risk, improving the postoperative stability and healing effect.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and specifically to a bone anchor implantation device. Background Technology

[0002] Anchors are implantable medical devices widely used in the medical field, especially in orthopedics and sports medicine. They are typically used to reliably fix soft tissues such as tendons, ligaments, joint capsules, and labrum to the bone surface or within bone tunnels, promoting the healing and reconstruction of the soft tissue-bone interface and thus restoring joint stability and normal function. Compared to traditional methods such as transosseous sutures and wire / screw fixation, suture anchors offer advantages such as reliable fixation, minimally invasiveness, relatively simplified operation path, and compatibility with arthroscopic surgery. They effectively improve problems such as difficulty in fixing the soft tissue-bone interface, insufficient early postoperative stability, and fluctuating efficacy. Therefore, they are widely used in minimally invasive repair surgeries of joints such as the shoulder, knee, and ankle, promoting the development of minimally invasive orthopedic and arthroscopic techniques.

[0003] In existing technologies, the suture anchor structure includes a suture extending through a suture groove inside the anchor body and exiting from one of the suture holes to the outside of the anchor body. The suture then circles half a circumference of the anchor body along the gap between the threads on the outside, before entering the suture groove inside the anchor body through another suture hole and exiting from the tail end of the anchor body. This structural design maintains the integrity of the anchor body's thread structure while ensuring the suture's function, and the large coverage area of ​​the outer side of the anchor body over bone tissue results in strong connection stability after connection with the bone.

[0004] However, in clinical practice, especially when dealing with patients with osteoporosis, factors such as sparse trabeculae, decreased bone density, and thinning of the cortex significantly weaken the supporting and frictional forces at the bone-anchor interface. This makes anchors, which traditionally rely on threaded engagement or local compression for fixation, more prone to early micromovement, leading to loosening, displacement, or even detachment. This affects the retention of soft tissue repositioning and the quality of interface healing, prolonging the rehabilitation period and potentially requiring reoperation in severe cases. Furthermore, some existing anchors still have shortcomings in structural control, mechanical matching, and biocompatibility, which may further amplify the risk of failure under osteoporotic conditions.

[0005] In addition, existing suture anchors are unstable in osteoporosis patients. Due to the insufficient load-bearing capacity and interfacial friction of osteoporotic bone tissue, the anchors are prone to loosening, displacement or detachment, resulting in soft tissue fixation failure and affecting postoperative stability and healing effect. Furthermore, it is difficult to precisely control the degree of anchor expansion during the operation. Summary of the Invention

[0006] This invention provides a bone anchor implantation device to solve the problems of poor fixation stability and complex surgical procedures of existing anchors in osteoporosis patients.

[0007] This invention provides a bone anchor implantation device, comprising: a bone anchor, an expansion drive shaft, an implantation assembly, and a drive mechanism; the bone anchor includes an anchor body, the distal end of which forms a radially outwardly flared petal structure; one end of the expansion drive shaft passes through the anchor body, and the expansion drive shaft rotates to form a threaded drive with the anchor body and drive the petal structure to expand radially outward; the distal end of the implantation assembly is detachably connected to the anchor body, and the other end of the expansion drive shaft passes through the implantation assembly from the distal end; the drive mechanism is disposed on the implantation assembly, the drive end of the drive mechanism passes through the implantation assembly and is connected to the other end of the expansion drive shaft for driving the expansion drive shaft to rotate.

[0008] The beneficial effects are as follows:

[0009] By forming a radially outward-expanding petal-like structure at the distal end of the anchor body, and achieving threaded transmission between the petal-like structure and the anchor body through the rotation of the expansion drive shaft, the anchor is driven to expand radially outward, providing an anchoring effect within the bone. This increases the contact area and occlusion range with low-density bone, reducing the risk of pull-out. The threaded transmission between the expansion drive shaft and the anchor body allows for gradual expansion displacement with rotation angle. Relatively precise expansion control is achieved through the implantation component and drive mechanism, enabling on-demand adjustment of the outward expansion degree of the petal-like structure and reducing surgical complexity. The detachable connection design between the implantation component and the anchor body allows for separation of the device and anchor after expansion and locking. The drive mechanism, located on the implantation component, directly drives the expansion drive shaft. The implantation component performs multiple steps including positioning, implantation, and expansion locking, reducing instrument changes and repeated alignment operations, thereby reducing operational complexity, shortening surgical time, and improving operational efficiency. This bone anchor implantation device effectively improves surgical efficiency and implantation accuracy while ensuring the stability of bone anchor implantation and fixation, thus reducing intraoperative risks and improving postoperative stability and healing outcomes.

[0010] According to some embodiments of the present invention, the distal end of the anchor body is provided with an expansion head, the expansion head is integrally formed with the anchor body, the expansion head has at least two expansion grooves spaced apart along the circumferential direction, so that the expansion head forms the petal-shaped structure that can expand radially outward; there are four expansion grooves, the four expansion grooves are evenly spaced along the circumference of the expansion head, and the expansion head is provided with a conical structure. The outer surface of the expansion head is provided with a fixing thread, and the fixing thread has a notch on the side near the expansion groove so that the petal structure expands outward; The outer surface of the anchor body is provided with reinforcing threads.

[0011] According to some embodiments of the present invention, the anchor body and / or the expansion head are both made of biodegradable materials, and the outer surface is provided with a coating for regulating the degradation rate. The coating is applied to the outer wall of the fixing thread and / or the outer wall of the reinforcing thread to delay the degradation of the thread area.

[0012] According to some embodiments of the present invention, the bone anchor further includes a suture that passes through the expansion drive shaft and exits from the proximal end of the anchor body, the suture being used for connection with soft tissue; The expansion drive shaft is provided with: a positioning hole, a threading hole, and a storage groove; the positioning hole is located at the proximal end of the expansion drive shaft, and the driving end of the drive mechanism passes through the positioning hole to be connected to the expansion drive shaft for transmission; the threading hole is located inside the expansion drive shaft for the thread to pass through, and the opening direction of the threading hole is radially opened along the expansion drive shaft; the storage groove is opened on the outer periphery of the expansion drive shaft, and at least two grooves are provided, and the storage groove is used to store the thread.

[0013] According to some embodiments of the present invention, the anchor body has a layered structure, comprising, from the inside out, a core layer, a growth layer, and the coating layer, wherein: The core layer is a dense magnesium alloy substrate and is threadedly connected to the expansion drive shaft; the growth layer is disposed on the outside of the core layer and has a porous structure; the coating is applied to the outside of the growth layer to regulate degradation.

[0014] According to some embodiments of the present invention, the coating comprises a biodegradable polymer and a bone conduction material, wherein the biodegradable polymer is a polylactic acid-glycolic acid copolymer, and the bone conduction material comprises hydroxyapatite and / or bioactive molecules.

[0015] According to some embodiments of the present invention, the implantation assembly includes an implantation rod and an implantation mechanism; the implantation rod is a hollow structure, the distal end of the implantation rod is detachably connected to the proximal end of the anchor body, the proximal end of the implantation rod is connected to the implantation mechanism, the expansion drive shaft passes through the distal end of the implantation rod into the implantation rod, the drive mechanism is disposed on the implantation mechanism, and the drive end of the drive mechanism passes through the implantation rod.

[0016] The implantation mechanism is adapted to control the positioning and implantation of the bone anchor. According to some embodiments of the present invention, the implantation mechanism includes an implantation handle and an adjustment block; The adjustment block is mounted on the implant handle via a rotating component and is connected to the implant rod via a transmission connection, so as to control the separation between the implant rod and the bone anchor. The implant handle is provided with the clearance hole, which is provided through to allow the drive mechanism to extend into and drive the expansion drive shaft.

[0017] According to some embodiments of the present invention, the driving mechanism includes a rotating cylinder, a rotating block, a fixed block, and a positioning block; The rotating cylinder is threadedly connected to the implantation mechanism. The rotating block is disposed on the outside of the rotating cylinder to drive the rotating cylinder to rotate. The fixing block is disposed on the inside of the rotating cylinder. The positioning block is disposed on the fixing block and is detachably engaged with the positioning hole of the expansion drive shaft to transmit the torque of the rotating cylinder to the expansion drive shaft.

[0018] According to some embodiments of the present invention, both the positioning block and the positioning hole are hexagonal structures, and the inner diameter of the rotating cylinder is larger than the diameter of the central expansion drive shaft, so that the stitching enters the interior of the rotating cylinder and avoids tangling. Attached Figure Description

[0019] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is an axial view of a bone anchor implantation device provided in some embodiments of the present invention; Figure 2 This is a front view of a bone anchor implantation device provided in some embodiments of the present invention; Figure 3 This is an installation view of the bone anchor and expansion drive shaft provided in some embodiments of the present invention; Figure 4 This is a partial structural schematic diagram of a bone anchor implantation device provided in some embodiments of the present invention; Figure 5 This is a structural view of the drive mechanism provided in some embodiments of the present invention; Figure 6 This is a structural view of the expansion drive shaft provided in some embodiments of the present invention; Figure 7 This is an installation view of the implanted components and drive mechanism provided in some embodiments of the present invention.

[0021] Explanation of reference numerals in the attached figures: 1. Bone anchor; 11. Anchor body; 12. Expansion head; 13. Suture; 111. Reinforcing thread; 121. Expansion groove; 122. Fixing thread; 2. Expansion drive shaft; 21. Positioning hole; 22. Thread hole; 23. Storage groove; 3. Implantation assembly; 31. Implantation rod; 32. Implantation mechanism; 321. Implantation handle; 322. Adjustment block; 4. Drive mechanism; 41. Rotating cylinder; 42. Rotating block; 43. Positioning block. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Reference Figure 1 , Figure 2 and Figure 3 As shown, the present invention provides a bone anchor 1 implantation device, comprising: a bone anchor 1, an expansion drive shaft 2, an implantation assembly 3, and a drive mechanism 4; the bone anchor 1 includes an anchor body 11, the distal end of which forms a radially outwardly flared petal structure; one end of the expansion drive shaft 2 passes through the anchor body 11, and the expansion drive shaft 2 rotates to form a threaded transmission with the anchor body 11 and drive the petal structure to expand radially outward; the distal end of the implantation assembly 3 is used for detachable connection with the anchor body 11, and the other end of the expansion drive shaft 2 passes through the distal end of the implantation assembly 3 and is inserted into the implantation assembly 3; the drive mechanism 4 is disposed on the implantation assembly 3, the drive end of the drive mechanism 4 passes through the implantation assembly 3 and is connected to the other end of the expansion drive shaft 2 for driving the expansion drive shaft 2 to rotate.

[0024] Specifically, a radially outward-expanding petal-like structure is formed at the distal end of the anchor body 11. This structure is driven by the expansion drive shaft 2, which rotates to achieve threaded transmission with the anchor body 11. This drives the petal-like structure to expand radially outward, providing an anchoring effect within the bone, increasing the contact area and occlusion range with low-density bone, and reducing the risk of pull-out. The threaded transmission between the expansion drive shaft 2 and the anchor body 11 allows for gradual expansion displacement with rotation angle. Relatively precise expansion control is achieved through the implantation component 3 and the drive mechanism 4. This allows for on-demand adjustment of the outward expansion degree of the petal-like structure, reducing surgical complexity. The detachable connection design between the implantation component 3 and the anchor body 11 allows for separation of the device and anchor after expansion and locking. The drive mechanism 4, mounted on the implantation component 3, directly drives the expansion drive shaft 2. The implantation component 3 performs multiple steps including positioning, implantation, and expansion and locking, reducing instrument changes and repeated alignment operations, thereby reducing operational complexity, shortening surgical time, and improving operational efficiency. This bone anchor implantation device effectively improves surgical efficiency and implantation accuracy while ensuring the stability of bone anchor implantation and fixation, thereby reducing intraoperative risks and improving postoperative stability and healing effect.

[0025] Understandably, the radial outward expansion of the lobed structure forms a multi-lobed distributed support, which can achieve a more uniform force transmission within the bone tissue. Compared with a single threaded segment or point support method, it helps to reduce the risk of bone cutting effect or loosening caused by local stress concentration, thereby improving long-term fixation reliability.

[0026] Reference Figure 3 and Figure 4 As shown, in some embodiments of the present invention, the distal end of the anchor body 11 is provided with an expansion head 12, the expansion head 12 is integrally formed with the anchor body 11, and the expansion head 12 has at least two expansion grooves 121 arranged circumferentially to form a petal-shaped structure that can expand radially outward.

[0027] Specifically, by providing an expansion head 12 integrally formed with the anchor body 11 at the distal end of the anchor body 11, the assembly connection interface between the expansion head 12 and the anchor body 11 is avoided, reducing the risk of loosening, detachment, or fatigue fracture at the connection point, thereby improving the overall structural strength and long-term reliability after implantation. The expansion head 12 is provided with at least two expansion grooves 121 spaced circumferentially, causing the expansion head 12 to form a petal-like structure and achieve radial outward expansion when acted upon by the expansion drive shaft 2. The expansion grooves 121 provide guidance for the outward expansion path of the petal-like structure, improving the predictability and consistency of the outward expansion process, thereby enhancing the stability of the anchoring effect.

[0028] Understandably, the multiple expansion grooves 121 provide circumferential distributed support to the outwardly expanded flap structure, which can achieve a more uniform load distribution within the bone tissue, reduce stress concentration caused by single-point or unilateral expansion, reduce the risk of cortical bone fracture, cancellous bone compression and collapse, and help improve the safety and durability of postoperative fixation.

[0029] In the non-expanded state, the segmented structure corresponding to the expansion groove 121 still maintains a relatively compact overall outline; the outward expansion action occurs after implantation and positioning, which can take into account the needs of easy advancement during the implantation stage and radial expansion and anchoring during the locking stage, thereby improving instrument passability and operational smoothness, further simplifying surgical operations and reducing operational difficulty.

[0030] Reference Figure 4 As shown, in some embodiments of the present invention, there are four expansion grooves 121, which are evenly spaced along the circumference of the expansion head 12, and the expansion head 12 is a conical structure.

[0031] Specifically, by setting the expansion grooves 121 into four evenly spaced ones along the circumference of the expansion head 12, a four-lobed symmetrical expansion structure is formed when the expansion head 12 expands outward. This provides more balanced support and more consistent radial engagement in the circumferential direction, thereby reducing the risks of anchor tilting and local loosening caused by eccentric expansion, and improving pull-out and rotational stability in osteoporosis patients. The expansion head 12 is set into a conical structure, which allows the propulsion / rotation action of the expansion drive shaft 2 to be converted into a smoother radial component force, achieving gradual outward expansion from small to large. Compared with abrupt expansion, the conical guide helps to reduce the instantaneous impact and compression on the surrounding bone tissue, reduce the risk of complications such as bone fracture and cancellous bone collapse, and improve implantation safety.

[0032] Understandably, the conical shape offers better insertion and penetration characteristics during implantation, reducing resistance and improving alignment when entering the bone tunnel. After positioning, four-flap outward locking further enhances overall operative smoothness and clinical fit. The four-flap outward expansion creates a more circumferentially continuous support profile, achieving greater effective contact coverage and a more uniform friction / interlocking distribution with the same outward expansion compared to two-flap or non-uniformly distributed structures. This further improves pull-out resistance and rotational stability, addressing the poor fixation stability issues in existing techniques.

[0033] In some embodiments of the present invention, the outer surface of the expansion head 12 is provided with a fixing thread 122, and the fixing thread 122 is provided with a notch on the side near the expansion groove 121 so that the petal structure expands outward. The outer surface of the anchor body 11 is provided with reinforcing threads 111.

[0034] Specifically, by setting a fixing thread 122 on the outer surface of the expansion head 12, the bone anchor 1 can achieve initial fixation by engaging with the bone tissue during the implantation stage; subsequently, the flap-like structure expands radially to form a secondary locking, constructing a composite anchoring mechanism, which significantly improves the pull-out resistance and rotation resistance; the fixing thread 122 has a notch on the side near the expansion groove 121, providing deformation release space for the flap expansion corresponding to the expansion groove 121, avoiding interference, jamming or local tearing of the thread segment during the expansion process; at the same time, the thread still maintains effective engagement in the unnotched area.

[0035] By providing reinforcing threads 111 on the outer surface of the anchor body 11, additional threaded anchoring length can be provided in the body section other than the expansion head 12, so that the load is distributed axially to other bone contact areas, reducing stress concentration and bone cutting effect caused by single expansion zone bearing, thereby improving the overall pull-out resistance and reducing the risk of bone damage.

[0036] Understandably, the fixed thread 122 and the reinforcing thread 111 work together to give the anchor a clearer guide and a more stable pushing posture during the screwing process, reducing yaw, slippage or repeated corrections; and the notch and expansion groove 121 help to achieve smooth outward expansion, which helps to reduce jamming and adjustment times during the expansion stage, thereby further simplifying the surgical operation and improving efficiency.

[0037] In some embodiments of the present invention, the anchor body 11 and / or the expansion head 12 are both made of biodegradable materials, and the outer surface is provided with a coating for regulating the degradation rate. The coating is applied to the outer wall of the fixing thread 122 and / or the outer wall of the reinforcing thread 111 to delay the degradation of the thread area.

[0038] Specifically, biodegradable materials are used as the materials for the anchor body 11 and / or the expansion head 12, such as magnesium-based metals and zinc-based metals. This allows the bone anchor 1 to gradually degrade and be absorbed after providing phased mechanical support, thereby reducing the need for subsequent removal. Simultaneously, by applying a coating to the outer surface to regulate the degradation rate, the bone anchor 1 can maintain the necessary structural integrity and anchoring strength in the early postoperative period, better meeting the requirements for stable fixation during tissue healing. Applying the coating to the outer wall of the fixing thread 122 and / or the reinforcing thread 111 protects the load-bearing and occlusal areas, reducing the risk of passivation, defects, or occlusal failure of the thread teeth due to early degradation, thereby improving pull-out and rotation resistance.

[0039] Understandably, by regulating the degradation rate through coating, the degradation of the threaded area can be relatively delayed, while non-critical areas can degrade faster or normally as designed. This reduces the risk of complications such as early loosening and fixation failure caused by excessively rapid degradation, thereby improving overall treatment safety. The coating's coverage of the outer wall of the thread can act as a barrier, slowing down the rapid corrosion process of magnesium alloy in the body fluid environment. This helps maintain bone interface stability, promotes early bone integration / fibrous tissue stabilization, and improves the predictability of implantation outcomes.

[0040] In some embodiments of the present invention, the bone anchor 1 further includes a suture 13, which passes through the expansion drive shaft 2 and is led out from the proximal end of the anchor body 11. The suture 13 is used to connect with soft tissue. Reference Figure 6 As shown, the expansion drive shaft 2 is provided with: a positioning hole 21, a threading hole 22, and a storage groove 23; the positioning hole 21 is located at the near end of the expansion drive shaft 2, and the driving end of the drive mechanism 4 passes through the positioning hole 21 to be connected to the expansion drive shaft 2 for transmission; the threading hole 22 is located inside the expansion drive shaft 2 for the thread 13 to pass through, and the opening direction of the threading hole 22 is opened along the radial direction of the expansion drive shaft 2; the storage groove 23 is opened on the outer periphery of the expansion drive shaft 2, and at least two are provided, and the storage groove 23 is used to store the thread 13.

[0041] Specifically, the suture 13 is threaded through the expansion drive shaft 2 and exits from the proximal end of the anchor body 11. After the anchor body 11 is implanted and expanded for locking, the suture 13 can be directly used to connect with the soft tissue without the need for additional threading or instrument replacement, thus reducing intraoperative procedures, surgical complexity, and efficiency. By placing the suture 13 within the threading hole 22 inside the expansion drive shaft 2, the suture 13 is protected by the shaft structure during implantation and expansion, reducing the risks of tangling, knotting, and abrasion from bone edges or instruments caused by suture exposure. This helps maintain the strength and reliability of the suture 13 and improves the smoothness of intraoperative operations. The opening direction of the threading hole 22 is radially along the expansion drive shaft 2, allowing the suture 13 to be more easily introduced or exited radially through the threading hole 22 channel. This facilitates rapid threading, suture replacement, or suture routing during surgery, reducing the time and probability of errors caused by complex threading paths.

[0042] It is understandable that a positioning hole 21 is provided near the expansion drive shaft 2, and the drive end of the drive mechanism 4 passes through the positioning hole 21 to be connected to the expansion drive shaft 2 for transmission. This can provide clear assembly positioning and a stable torque transmission path, reduce slippage or eccentric force, and improve the controllability of the rotation of the expansion drive shaft 2, thereby making the outward expansion of the petal structure more stable and predictable.

[0043] At least two storage grooves 23 are provided on the outer periphery of the expansion drive shaft 2 to store the suture 13. Multiple strands or redundant suture segments can be embedded into the grooves in an orderly manner, avoiding the suture 13 from being caught, clamped or accidentally cut during the rotation of the drive mechanism 4, instrument advancement or anchor expansion, reducing the risk of suture interference and damage, and improving intraoperative safety.

[0044] In some embodiments of the present invention, the anchor body 11 has a layered structure, comprising, from the inside out, a core layer, a growth layer, and a coating layer, wherein: The core layer is a dense magnesium alloy matrix and is threadedly connected to the expansion drive shaft 2; the growth layer is set outside the core layer and has a porous structure; the coating is applied to the outside of the growth layer to regulate degradation.

[0045] Specifically, the anchor body 11 adopts a layered structure consisting of a core layer, a growth layer, and a coating layer. The core layer is a dense magnesium alloy matrix, which provides the structural strength required for load-bearing and resistance to torsion / pull-out in the early stages of implantation. The growth layer has a porous structure, which is conducive to bone tissue ingrowth and interface integration. The outer coating layer is used to regulate the degradation rate. The synergistic effect of these three components enables the anchor body 11 to meet the early stability and fixation requirements while gradually achieving interface stabilization and biointegration in the later stages, thus improving long-term fixation reliability.

[0046] The core layer is a dense magnesium alloy matrix and is threadedly connected to the expansion drive shaft 2. This reduces the adverse effects of the porous structure on the thread meshing accuracy and load-bearing capacity, reduces the risk of collapse, wear or stripping at the threaded connection, thereby improving the stability of the rotational transmission of the expansion drive shaft 2 and making the outward expansion process of the petal structure more controllable and consistent.

[0047] The growth layer has a porous structure, which provides space and attachment interface for the growth of osteocytes / trabeculae, promotes the ingrowth of bone tissue into the anchor surface and pores, and forms a more stable mechanical interlocking and biological fixation effect. In cases of osteoporosis and other conditions with weak bone holding power, it can effectively reduce the risk of interface micromovement and long-term loosening, and improve pull-out stability.

[0048] The coating is applied to the outside of the growth layer to regulate degradation, which can delay the rapid corrosion of magnesium alloys in the body fluid environment and reduce problems such as structural weakening and interface disturbance caused by early degradation. At the same time, it makes the degradation process more predictable, which helps to better match the strength retention period with the tissue healing period and improve clinical safety.

[0049] In some embodiments of the present invention, the coating comprises a biodegradable polymer and a bone conduction material, wherein the biodegradable polymer is a polylactic acid-glycolic acid copolymer, and the bone conduction material comprises hydroxyapatite and / or bioactive molecules.

[0050] In some embodiments of the present invention, the magnesium alloy used to prepare the anchor body 11 and / or the expansion head 12 is a medical-grade magnesium alloy, comprising, by weight percentage: Zn 1.7%–2.0%, Ca 0.4%–0.6%, Mn 1.0%–1.2%, and impurity elements satisfying: Ni < 0.003%, Fe < 0.03%, Cu < 0.0001%, Si < 0.01%. This magnesium alloy exhibits good biocompatibility and biodegradability.

[0051] In the preparation process, firstly, the magnesium alloy raw material is melted in a high-temperature furnace to form a uniform alloy melt. By precisely controlling the melting temperature and time, the uniformity of the alloy composition is ensured. Then, using precision casting technology, the alloy melt is injected into a pre-designed anchor mold. After cooling and solidification, a preliminary blank of the magnesium alloy anchor is obtained. Next, the blank is machined, such as by turning and milling, to precisely control the size and shape of the anchor so that it meets the standard requirements for clinical use. Subsequently, a combination of chemical etching and physical treatment was used to create nanopores on the outer wall of the magnesium alloy body. The processed magnesium alloy anchor was immersed in a specific chemical etching solution. By precisely controlling parameters such as etching time, solution concentration, and temperature, selective etching of the magnesium alloy surface was achieved, forming a preliminary micro-rough structure. Then, plasma treatment technology was used to further treat the anchor surface, further refining the surface microstructure and ultimately forming uniformly distributed nanopores. The diameter of these nanopores ranges from tens to hundreds of nanometers, and the depth can be adjusted according to actual needs, generally controlled within the range of a few micrometers to tens of micrometers. Finally, a coating is applied to the surface of the anchor body 11 and / or the expansion head 12. The coating is a composite material mainly composed of polylactic acid-glycolic acid copolymer (PLGA), hydroxyapatite (HA), and a small amount of bioactive molecules. PLGA is a polymer material with good biocompatibility and biodegradability. Its degradation rate can be precisely controlled by adjusting the ratio of lactic acid to glycolic acid. HA is the main inorganic component of human bone and can promote the adhesion, proliferation, and differentiation of osteocytes, enhancing the bonding strength between the anchor and the surrounding bone tissue. Bioactive molecules such as bone morphogenetic proteins (BMPs) can further stimulate the regeneration and repair of bone tissue, improving the bioactivity of the anchor. The coating can be applied using a combination of spraying and electrochemical deposition. First, PLGA is dissolved in a suitable organic solvent to prepare a solution of a certain concentration, and then an appropriate amount of HA is added. Powder and bioactive molecules are thoroughly mixed to form a coating slurry. Using a spraying device, the coating slurry is evenly sprayed onto the surface of a magnesium alloy anchor with nanopores to form a preliminary coating layer. Next, the sprayed anchor is placed in an electrochemical deposition device, using the anchor as the working electrode. By selecting appropriate electrolyte and electrodeposition parameters, a uniform HA coating layer is further deposited on the surface of the preliminary coating layer through electrochemical action, making the coating more dense and uniform. Finally, the coated anchor is dried to remove residual organic solvents, resulting in the finished anchor.

[0052] The bone anchor 1, made of magnesium alloy, possesses high tensile strength, preventing breakage during expansion. Due to the excellent biocompatibility of magnesium alloy, it provides a suitable microenvironment for the adhesion, proliferation, and differentiation of bone cells such as osteoblasts and osteoprogenitors. Bone cells can better adhere to the surface of the magnesium alloy implant, forming a cell layer and secreting extracellular matrix, promoting bone tissue formation and reconstruction. Furthermore, after implantation, the tissue reaction around the magnesium alloy is mild, without triggering significant inflammatory or foreign body rejection reactions. This helps maintain local environmental stability at the implantation site and reduces stress on the bone. Interference with the healing process creates favorable conditions for the normal growth and repair of bone tissue. Magnesium alloys can gradually degrade in the body's physiological environment, a process that matches the healing cycle of bone tissue. Magnesium alloy materials cause the anchor to undergo an electrochemical corrosion reaction in the body's physiological environment, gradually degrading it. The magnesium element in the magnesium alloy loses electrons in the body fluids to form magnesium ions. At the same time, oxygen and water in the body fluids participate in the reaction, generating degradation products such as magnesium hydroxide. These degradation products can be gradually absorbed and metabolized by the body, and eventually the anchor completely degrades and disappears without the need for a second surgery to remove it, avoiding the pain and financial burden of surgery for the patient again.

[0053] The PLGA component in the coating gradually hydrolyzes within the human body at a relatively slow degradation rate, forming a protective barrier on the anchor surface. This slows down the direct contact between the magnesium alloy anchor and body fluids, thus delaying the anchor's degradation process. Simultaneously, the HA component not only possesses excellent bioactivity but also reacts with calcium and phosphorus ions in body fluids to form a mineralized layer similar to bone tissue, further enhancing the coating's stability and degradation-delaying ability. The bioactive molecules promote bone tissue regeneration and repair, accelerating the integration of the bone anchor 1 with surrounding bone tissue, enabling the bone anchor 1 to better perform its fixation function in vivo while extending its degradation time to meet clinical treatment needs. Through the above manufacturing process and coating design, the bone anchor 1 in this application achieves a perfect combination of the self-degradation function of the magnesium alloy material and the degradation-delaying function of the coating, providing a safer, more effective, and convenient implant material for clinical medicine, especially suitable for bone fixation treatment of osteoporosis patients.

[0054] Reference Figure 1 and Figure 2 As shown, in some embodiments of the present invention, the implantation component 3 includes an implantation rod 31 and an implantation mechanism 32; the implantation rod 31 has a hollow structure, the distal end of the implantation rod 31 is detachably connected to the proximal end of the anchor body 11, the proximal end of the implantation rod 31 is connected to the implantation mechanism 32, the expansion drive shaft 2 passes through the distal end of the implantation rod 31 and into the implantation rod 31, and the drive mechanism 4 is disposed on the implantation mechanism 32, with the drive end of the drive mechanism 4 passing through the implantation rod 31; The implantation mechanism 32 is adapted to control the positioning and implantation of the bone anchor 1.

[0055] Specifically, the implant rod 31 adopts a hollow structure. The expansion drive shaft 2 passes through the distal end of the implant rod 31 and is located inside the implant rod 31. The drive end of the drive mechanism 4 also passes through the implant rod 31, making the implantation advancement axis and the expansion drive axis coaxial. This helps to reduce eccentric force, swaying, or torque loss, thereby improving the stability and controllability of the anchor implantation and expansion locking process. The distal end of the implant rod 31 is detachably connected to the proximal end of the anchor body 11, allowing the implantation component 3 to quickly withdraw and separate from the anchor after the anchor is implanted and expanded and locked. This reduces instrument retention and repeated operations, reduces traction on the incision and surrounding soft tissues, helps to simplify the surgical procedure, and improves minimally invasive adaptability.

[0056] It is understandable that the implantation component 3 consists of an implantation rod 31 and an implantation mechanism 32. The proximal end of the implantation rod 31 is connected to the implantation mechanism 32, which facilitates the replacement of implantation rods 31 of different lengths or structural forms according to different surgical approaches, depths or operating habits, thereby improving clinical adaptability and facilitating the cleaning, disinfection and maintenance of instruments.

[0057] The expansion drive shaft 2 is placed inside the implant rod 31. During advancement, insertion, or positioning, it is shielded and protected by the implant rod 31, reducing the risk of bending, collision, or friction and interference with bone edges / soft tissue caused by the exposed drive shaft, thereby improving the reliability of instrument use and intraoperative safety.

[0058] The drive mechanism 4 is mounted on the implantation mechanism 32. The drive end is transmitted to the expansion drive shaft 2 via the implantation rod 31. This allows the key rotational drive operation to be concentrated in the proximal control area, making it easier for doctors to apply stable torque and make fine adjustments. This improves the control accuracy of the valve structure's outward expansion and reduces over-expansion or under-expansion caused by inconvenient operation.

[0059] Reference Figure 7 As shown, in some embodiments of the present invention, the implantation mechanism 32 includes an implantation handle 321 and an adjustment block 322; The adjustment block 322 is mounted on the implant handle 321 via a rotating component and is connected to the implant rod 31 for transmission, so as to control the separation between the implant rod 31 and the bone anchor 1; The implant handle 321 is provided with a clearance hole, which is provided through to allow the drive mechanism 4 to extend into the drive expansion drive shaft 2.

[0060] Specifically, the adjusting block 322 is mounted on the implantation handle 321 via a rotating component and is connected to the implantation rod 31 via a transmission connection. It controls the separation of the implantation rod 31 from the bone anchor 1, allowing the surgeon to quickly separate the instrument from the anchor after implantation and expansion locking by adjusting the handle end. This reduces the need for repeated twisting, alignment, or instrument replacement, thereby reducing operational complexity and improving surgical efficiency. Because the adjusting block 322 operates around the rotating component, it allows for clear switching between locked and unlocked states, maintaining a stable connection between the implantation rod 31 and the bone anchor 1 during implantation or expansion. If necessary, it can be separated according to a preset action, reducing the risk of unexpected dislodgement due to vibration, force, or misoperation during surgery, and improving the reliability and safety of instrument use.

[0061] Understandably, once the adjustment block 322 and the implantation rod 31 establish a transmission relationship, the disassembly action can be completed through the proximal handle area without having to remove the entire instrument or perform complex operations in a deep, confined space. This allows doctors to achieve rapid and controllable disassembly under minimally invasive approaches or limited visual fields, improving intraoperative convenience and accessibility.

[0062] The implanted handle 321 is provided with a through clearance hole for the drive mechanism 4 to extend into the drive expansion drive shaft 2. This provides a clear entry channel and space clearance for the drive end, reduces the risk of interference and jamming between the drive mechanism 4 and the handle structure, ensures smooth torque transmission, and thus improves the stability and controllability of the rotation of the expansion drive shaft 2 and the outward expansion of the petal structure.

[0063] Reference Figure 5 As shown, in some embodiments of the present invention, the drive mechanism 4 includes a rotating cylinder 41, a rotating block 42, a fixed block, and a positioning block 43; The rotating cylinder 41 is threadedly connected to the implantation mechanism 32. The rotating block 42 is located on the outside of the rotating cylinder 41 to drive the rotating cylinder 41 to rotate. The fixed block is located on the inside of the rotating cylinder 41. The positioning block 43 is located on the fixed block and is detachably engaged with the positioning hole 21 of the expansion drive shaft 2 to transmit the torque of the rotating cylinder 41 to the expansion drive shaft 2.

[0064] Specifically, the rotating cylinder 41 is threadedly connected to the implantation mechanism 32, so that the drive mechanism 4 can be reliably installed, fixed and axially positioned on the implantation mechanism 32. It is not easy to cause swaying or shaking during rotation, thereby improving the stability of the drive torque output, ensuring smoother rotation of the expansion drive shaft 2, and improving the controllability of the outward expansion of the petal structure.

[0065] The rotating block 42 is located on the outside of the rotating cylinder 41 and is used to drive the rotating cylinder 41 to rotate. It can increase the contact area diameter and facilitate the screwing operation. At the same time, it is conducive to applying torque more efficiently and realizing fine angle adjustment, thereby reducing the difficulty of expansion operation.

[0066] A fixing block is located inside the rotating cylinder 41, providing support and limiting for the positioning block 43 and transmission components. This reduces torque loss caused by component sway, looseness, or meshing during rotation, thereby improving the efficiency and consistency of torque transmission from the rotating cylinder 41 to the expansion drive shaft 2. The positioning block 43 is detachably engaged with the positioning hole 21 of the expansion drive shaft 2, allowing for quick assembly and disengagement when drive is needed, and rapid disengagement after expansion. Furthermore, the engagement structure is less prone to slippage compared to pure friction contact, establishing a clear torque transmission interface, reducing the risk of insufficient expansion or misoperation due to slippage, and improving transmission reliability.

[0067] In some embodiments of the present invention, the outer periphery of the implant handle 321 is provided with anti-slip grooves to increase contact friction, thereby ensuring the stability of intraoperative operation.

[0068] Reference Figure 6 As shown, in some embodiments of the present invention, both the positioning block 43 and the positioning hole 21 are hexagonal structures, and the inner diameter of the rotating cylinder 41 is larger than the diameter of the central expansion drive shaft 2, so that the stitch 13 can enter the interior of the rotating cylinder 41 and avoid tangling.

[0069] Specifically, both the positioning block 43 and the positioning hole 21 are designed as hexagonal structures, which can form a surface contact shape fit. Compared with the circular friction fit, it is less prone to slippage and can transmit torque more stably during the expansion drive process, reducing the risk of idling. This improves the accuracy of the rotation of the expansion drive shaft 2 and the consistency of the outward expansion of the petal structure. The inner diameter of the rotating cylinder 41 is larger than the diameter of the central expansion drive shaft 2, allowing the suture 13 to enter the interior of the rotating cylinder 41 and obtain the necessary clearance space. This reduces the probability of the suture 13 being clamped, rubbed, and tangled with the inner wall of the rotating cylinder 41 or the outer surface of the drive shaft when the drive mechanism 4 rotates. This reduces the risk of suture 13 wear, breakage, or knotting, and improves the safety and reliability of the suture-supported bone anchor 1.

[0070] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A bone anchor implantation device, characterized in that, include: Bone anchor (1), including anchor body (11), the distal end of which forms a radially outwardly flared structure; An expansion drive shaft (2) is inserted at one end into the anchor body (11). The expansion drive shaft (2) rotates to form a threaded transmission with the anchor body (11) and drive the petal structure to expand radially outward. An implant component (3) is provided, the distal end of which is detachably connected to the anchor body (11), and the other end of the expansion drive shaft (2) passes through the implant component (3) from the distal end of the implant component (3). A drive mechanism (4) is disposed on the implantation component (3). The drive end of the drive mechanism (4) passes through the implantation component (3) and is connected to the other end of the expansion drive shaft (2) to drive the expansion drive shaft (2) to rotate.

2. The bone anchor implantation device according to claim 1, characterized in that, The anchor body (11) has an expansion head (12) at its distal end. The expansion head (12) is integrally formed with the anchor body (11). The expansion head (12) has at least two expansion grooves (121) spaced apart in the circumferential direction, so that the expansion head (12) forms the petal-shaped structure that can expand outward in the radial direction. There are four expansion grooves (121), and the four expansion grooves (121) are evenly spaced along the circumference of the expansion head (12). The expansion head (12) is a conical structure. The outer surface of the expansion head (12) is provided with a fixing thread (122), and the fixing thread (122) has a notch on the side near the expansion groove (121) so that the petal structure expands outward; The outer surface of the anchor body (11) is provided with reinforcing threads (111).

3. The bone anchor implantation device according to claim 2, characterized in that, The anchor body (11) and / or the expansion head (12) are both biodegradable materials, and the outer surface is provided with a coating for regulating the degradation rate. The coating is applied to the outer wall of the fixing thread (122) and / or the outer wall of the reinforcing thread (111) to delay the degradation of the thread area.

4. The bone anchor implantation device according to claim 2, characterized in that, The bone anchor (1) also includes a suture (13) which passes through the expansion drive shaft (2) and exits from the proximal end of the anchor body (11). The suture (13) is used to connect with soft tissue. The expansion drive shaft (2) is provided with: a positioning hole (21), a threading hole (22), and a storage groove (23); the positioning hole (21) is located at the near end of the expansion drive shaft (2), and the driving end of the drive mechanism (4) passes through the positioning hole (21) to be connected to the expansion drive shaft (2) for transmission; the threading hole (22) is located inside the expansion drive shaft (2) for the thread (13) to pass through, and the opening direction of the threading hole (22) is opened along the radial direction of the expansion drive shaft (2); the storage groove (23) is opened on the outer periphery of the expansion drive shaft (2), and at least two grooves are provided, and the storage groove (23) is used to store the thread (13).

5. The bone anchor implantation device according to claim 3, characterized in that, The anchor body (11) has a layered structure, comprising, from the inside out, a core layer, a growth layer, and the coating layer, wherein: The core layer is a dense magnesium alloy substrate and is threadedly connected to the expansion drive shaft (2); the growth layer is disposed on the outside of the core layer and has a porous structure; the coating is applied to the outside of the growth layer to regulate degradation.

6. The bone anchor implantation device according to claim 5, characterized in that, The coating comprises a biodegradable polymer and a bone conduction material, wherein the biodegradable polymer is a polylactic acid-glycolic acid copolymer and the bone conduction material comprises hydroxyapatite and / or bioactive molecules.

7. The bone anchor implantation device according to claim 4, characterized in that, The implantation assembly (3) includes an implantation rod (31) and an implantation mechanism (32); the implantation rod (31) is a hollow structure, the distal end of the implantation rod (31) is detachably connected to the proximal end of the anchor body (11), the proximal end of the implantation rod (31) is connected to the implantation mechanism (32), the expansion drive shaft (2) passes through the distal end of the implantation rod (31) into the implantation rod (31), the drive mechanism (4) is disposed on the implantation mechanism (32), and the drive end of the drive mechanism (4) passes through the implantation rod (31); The implantation mechanism (32) is adapted to control the positioning and implantation of the bone anchor (1).

8. The bone anchor implantation device according to claim 7, characterized in that, The implantation mechanism (32) includes an implantation handle (321) and an adjustment block (322); The adjustment block (322) is mounted on the implant handle (321) via a rotating component and is connected to the implant rod (31) for transmission, so as to control the separation between the implant rod (31) and the bone anchor (1); The implant handle (321) is provided with a clearance hole, which is provided through to allow the drive mechanism (4) to extend into and drive the expansion drive shaft (2).

9. The bone anchor implantation device according to claim 7, characterized in that, The drive mechanism (4) includes a rotating cylinder (41), a rotating block (42), a fixed block, and a positioning block (43). The rotating cylinder (41) is threadedly connected to the implantation mechanism (32). The rotating block (42) is located on the outside of the rotating cylinder (41) to drive the rotating cylinder (41) to rotate. The fixing block is located on the inside of the rotating cylinder (41). The positioning block (43) is located on the fixing block and is detachably engaged with the positioning hole (21) of the expansion drive shaft (2) to transmit the torque of the rotating cylinder (41) to the expansion drive shaft (2).

10. The bone anchor implantation device according to claim 9, characterized in that, Both the positioning block (43) and the positioning hole (21) are hexagonal structures, and the inner diameter of the rotating cylinder (41) is larger than the diameter of the expansion drive shaft (2) so that the stitch (13) can enter the interior of the rotating cylinder (41) and avoid tangling.

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