64 results about "Cancellous bone" patented technology

Surgical systems and methods for manipulation of an anatomy that includes cortical and cancellous bone. A surgical manipulator has a robotic arm to move an instrument with an energy applicator. A sensor senses forces / torques applied to the energy applicator. Controller(s) obtain a tool path for the energy applicator to traverse. A segment of the tool path transitions into, or between, cortical bone and cancellous bone. The controller(s) control the manipulator to advance the energy applicator along the tool path according to a first feed rate to manipulate the cortical or cancellous bone and detect, with the sensor, a change in the forces / torques being indicative of the transition. In response to detection of this change, the controller(s) control the manipulator to advance the energy applicator along the tool path according to a second feed rate, greater / less than the first feed rate.

The invention provides a natural bone repair material and a preparation method thereof. The material is animal cancellous bone inorganic salt particles or animal cancellous bone inorganic salt bone slices; the invention also relates to a preparation method of the natural bone repair material. The preparation method sequentially comprises the following steps: selecting materials, crushing, cleaning, removing organic matters, efficiently cleaning and drying, calcining and sterilizing. According to the method, inorganic base heating extraction and low-temperature calcination are adopted, so that the method is non-toxic, harmless, safe, efficient, low in organic matter residue and small in damage to the structure of a natural bone material, and the structure and morphology of the natural bone are better reserved; the defects of long construction period, low efficiency, high cost and the like existing in high-temperature calcination and organic reagent removal are avoided. The size of the bone repair material can be controlled, and the obtained bone repair material has certain mechanical strength, is not easy to break after being filled, and can play a good supporting role; and the material also has the advantages of high specific surface area, high porosity, low crystallinity, good hydrophilic performance, good biocompatibility and the like, and is suitable for bone defect repair.

The patent refers to a dental self-tapping implant comprising a body having a longitudinal body axis and a length, the body having a proximal neck portion, a proximal-central straight portion of substantially constant body diameter and a distal conical portion of decreasing diameter, the body comprising a core with a thread provided thereon, and a flute of circular arc shape formed in the thread which runs helicoidally around the core the flute having a longitudinal flute axis. The body has two segments: a cortical segment next to the proximal neck portion, a spongiosa segment extending the cortical segment the spongiosa segment including the distal conical portion, the sum of the cortical segment and the spongiosa segment being equal to the sum of the proximal-central straight portion and the distal conical portion; the flute is configured to run helicoidally around the core until it reaches the neck portion, so that the longitudinal flute axis forms a first angle with the longitudinal body axis along the cortical segment, and forms a second angle with the longitudinal body axis along the spongiosa segment; the first angle is larger than the second angle, the value of the first angle is directly proportional to the body diameter with a proportionality parameter within the interval [11;18], preferably within the interval [13,15].The patent further refers to a set comprising a dental self-tapping implant and a multi-step drill configured for the dental self-tapping implant, where the multi-step drill has four steps along the spongiosa segment, each step having a drill diameter and a step height; the drill diameters increase from the portion of the multi-step drill corresponding to the distal conical portion to the proximal-central straight portion; the body diameter is greater than the drill diameters at each step height; the step heights along the spongiosa segment have respective predetermined values irrespective of the body diameter; the drill diameters increase with the respective body diameter.

This invention provides an internal fixation device for cancellous bone, belonging to the field of medical device technology. It includes a fixation plate with a plurality of screw holes and positioning holes arranged in a linear array on its top outer wall; and a guide assembly connected to the fixation plate, used to guide the hollow self-drilling screws. By incorporating the guide assembly, this invention not only guides the hollow self-drilling screws, preventing them from deviating from their pre-operatively assessed position during insertion, thus affecting their fixation effect on the fracture site, but also holds the screws during the guiding process, preventing the screw head from tilting and protruding, which could cause skin irritation and affect postoperative recovery.

The application relates to a medical orthopedic quick drill bit, which comprises a drill bit body composed of a drill bit part and a drill rod part, wherein the drill bit part is provided with circularly arranged cutting edges for bone positioning and hole forming, and the drill rod part is designed as a light rod; a connecting piece is connected with the drill bit body at one end and fixed with a driving piece at the other end, and the two are quickly separated through a split device containing a clamping piece and a disengaging piece, so that safe disconnection is ensured when the pressure of the medullary cavity or cancellous bone is abnormal. The application has the technical effects of improving the operation efficiency, enhancing the safety and reducing accidental injuries.

The invention provides a bone evaluation method based on neural network enhancement and finite element analysis. The bone evaluation method comprises the following steps: acquiring an ultrahigh-resolution CT image of a living vertebra; performing domain conversion processing on the CT image by adopting a generative neural network; carrying out resampling and segmentation on the enhanced CT image; constructing a bone trabecula microstructure model in the cancellous bone mask area; assembling the RVE unit and the cortical bone model into a complete vertebral finite element model, and applying a multi-working-condition load to the RVE unit to calculate anisotropic material parameters; and carrying out axial compression finite element analysis on the complete centrum model, and judging the bone health state. According to the method, information of two dimensions of bone mass and bone, especially contribution of a bone trabecula microstructure to bone strength, is comprehensively considered, bone degeneration and fracture high-risk patients can be recognized earlier, and a scientific basis is provided for clinical early intervention.

The invention provides a cancellous bone internal fixing device, and belongs to the technical field of medical instruments. Comprising a fixing steel plate, a plurality of screw holes and a plurality of positioning holes are formed in the outer wall of the top of the fixing steel plate, and the screw holes and the positioning holes are distributed in a linear array mode; and the guide assembly is used for guiding the hollow self-drilling screw, and the guide assembly is connected with the fixed steel plate. By arranging the guiding assembly, the hollow self-tapping screw can be guided, the situation that the fixing effect of the hollow self-tapping screw on the fracture position of a patient is affected due to the fact that the hollow self-tapping screw deviates out of the designated position of preoperative evaluation in the screwing-in process is avoided, the hollow self-tapping screw can be held in the guiding process, and the fracture position of the patient is not affected. In this way, the situation that the screw head protrudes due to inclination, skin irritation is caused, and then postoperative recovery is affected can be avoided.

The present application belongs to the field of foot and ankle surgical implant devices and biomedical material surface engineering technology, and discloses a tibial component of ankle prosthesis with a composite coating, which comprises: a metal substrate which is a bionic trabecular three-dimensional interconnected porous titanium alloy structure, the porosity is 50-80%, the average pore size is 400-900 mu m, and the connected porosity is greater than or equal to 85%, so that the elastic modulus is controlled in the range of 5-20 GPa, and is matched with the cancellous bone of the tibia; a composite functional coating is in situ grown on the surface of the metal substrate, and the composite functional coating comprises a bioactive layer and a functional ion doped layer. The tibial component of the present application comprises a porous titanium alloy metal substrate and a composite functional coating constructed in situ on the surface thereof, the porous titanium alloy substrate is designed in a bionic trabecular structure to form a three-dimensional interconnected porous structure, so as to provide an elastic modulus matched with the cancellous bone of the tibia and promote the growth of bone tissue.

A suture-tension-activated anchoring system for fixing soft tissue to bone, the system comprising: a unitary implantable anchor body defining a longitudinal axis and having a proximal and a distal section; a proximal head unit formed on the proximal part of the anchor body and configured to interact with at least one repair suture; a tubular body unit extending distal to the proximal head unit and defining an internal longitudinal bore; a plurality of radially expandable rib elements arranged on the distal section of the tubular body unit and movable between a folded and an expanded configuration; and an internal cone unit positioned within the internal longitudinal bore and mechanically connected to at least one repair suture.wherein the application of a tensile force to the at least one repair suture causes a proximal axial displacement of the inner conical unit relative to the tubular body unit, wherein the proximal axial displacement of the inner conical unit generates a radial outward movement of the plurality of fin units from the folded to the unfolded configuration, and wherein the radial outward movement of the plurality of fin units anchors the anchor body in the cancellous bone without the need for an external deployment tool.

The invention provides a dental implant which comprises an implant body, and an implant thread matched with an alveolar bone is formed on the outer side wall of the implant body. The implant thread is made of a non-absorbable material and has good mechanical strength and biocompatibility. The surface of the implant thread is covered with the absorbable alloy layer, and the absorbable alloy layer is designed to be in a sharp thread form, so that bone injury in the implanting process is reduced. The absorbable alloy layer can be slowly absorbed by the alveolar bone after being implanted, so that the pressure on the cancellous bone is slowly reduced, the bone tissue healing is promoted, the stability of the dental implant is gradually consolidated and maintained, the reduction of peripheral inflammatory response or foreign body response is facilitated, and the long-term stability of the dental implant after being implanted is finally improved.

The application relates to the technical field of landing gears, in particular to a shock-absorbing landing gear imitating the head bone structure of a woodpecker and a preparation method, wherein the main body of the shock-absorbing landing gear is prepared from a TiAl alloy material, and the shock-absorbing landing gear comprises, from outside to inside, a strength layer, a buffer layer and a toughness layer; the strength layer imitates the hyoid layer of the head bone of a woodpecker; the buffer layer imitates the cancellous bone layer of the head bone of a woodpecker; and the toughness layer imitates the cerebrospinal fluid layer of the head bone of a woodpecker. The landing gear prepared by imitating the head bone structure of a woodpecker has excellent shock-absorbing and impact-resisting capacity; the landing gear is prepared by adopting a selective laser melting (SLM) technology, the number of connecting pieces in the landing gear is reduced, unnecessary assembly steps are saved, and assembly errors are reduced; the material and the part are integrally formed, and complicated preparation steps and machining processes are avoided.

The patent refers to a dental self-tapping implant comprising a body having a longitudinal body axis and a length, the body having a proximal neck portion, a proximal-central straight portion of substantially constant body diameter and a distal conical portion of decreasing diameter, the body comprising a core with a thread provided thereon, and a flute of circular arc shape formed in the thread which runs helicoidally around the core the flute having a longitudinal flute axis. The body has two segments: a cortical segment next to the proximal neck portion, a spongiosa segment extending the cortical segment the spongiosa segment including the distal conical portion, the sum of the cortical segment and the spongiosa segment being equal to the sum of the proximal-central straight portion and the distal conical portion; the flute is configured to run helicoidally around the core until it reaches the neck portion, so that the longitudinal flute axis forms a first angle with the longitudinal body axis along the cortical segment, and forms a second angle with the longitudinal body axis along the spongiosa segment; the first angle is larger than the second angle, the value of the first angle is directly proportional to the body diameter with a proportionality parameter within the interval (11; 18), preferably within the interval (13, 15). The patent further refers to a set comprising a dental self-tapping implant and a multi- step drill configured for the dental self-tapping implant, where the multi-step drill has four steps along the spongiosa segment, each step having a drill diameter and a step height; the drill diameters increase from the portion of the multi-step drill corresponding to the distal conical portion to the proximal-central straight portion; the body diameter is greater than the drill diameters at each step height; the step heights along the spongiosa segment have respective predetermined values irrespective of the body diameter; the drill diameters increase with the respective body diameter.

This application discloses a method, display method, apparatus, device, and storage medium for determining jawbone features. The method includes: obtaining a radicular bone scan image; segmenting the jawbone based on the radicular bone scan image to determine a segmented jawbone image; using a neural network, taking both the radicular bone scan image and the segmented jawbone image representing the same jawbone location as input, to determine a jawbone feature image and a cancellous bone feature image; comparing the jawbone feature image and the cancellous bone feature image, and determining a cortical bone feature image based on the differences; and determining and outputting cortical bone feature information based on the cortical bone feature image. The method provided in this application can improve the accuracy and efficiency of jawbone feature determination.

The application discloses a kind of biomimetic composite scaffold with periosteum-cortical bone-cancellous bone structure and its preparation method and application.The scaffold is assembled by independent periosteum biomimetic scaffold module and independent bone trunk biomimetic module.The periosteum biomimetic scaffold module is cylindrical tube structure hydrogel, loaded with zinc silicate particles and periosteum related cells, with the biological functions of promoting cartilage differentiation, secreting nerve and vascular factors and synthesizing periosteum matrix proteins.The bone trunk biomimetic scaffold module is cylindrical bioceramic, with multiple vertical pipes embedded in the dense layer of outer wall to simulate cortical bone, and with staggered structure inside to simulate cancellous bone.Animal experiments show that the biomimetic composite scaffold can effectively promote the integrated regeneration of bone trunk and periosteum in rabbit radial critical size defect model.Therefore, the application provides a new solution for the biomimetic design and regeneration repair of bone tissue engineering.

The invention relates to the technical field of surgical materials, in particular to an orthopedic external fixation splint based on an aluminum material and a preparation method thereof.The preparation method comprises the following steps that based on the bionic mechanics principle and cortical bone and cancellous bone modulus parameters of a target fixation part, a microscopic lattice structure model of a fixation splint base body with gradient modulus distribution is determined; based on the micro lattice structure model, additive manufacturing and gradient heat treatment of an aluminum matrix are executed by regulating and controlling selective laser melting process parameters, so that a basic component with the gradient mechanical property with the high outer portion and the low inner portion is obtained; the preparation method comprises the following steps: based on an aluminum substrate, carrying out surface activation treatment by adopting anodic oxidation, covalently grafting stress response type fluorescent molecules on the surface of the activated substrate, and constructing a uniform fluorescent signal layer; based on the matrix grafted with the functional molecules, a weather-resistant and optically transparent flexible packaging protection layer is determined and constructed through a micro gravure roller coating and multi-band ultraviolet curing technology. Overall support is provided through the outer layer, and stress is conducted to bone tissue through the inner layer.

The application discloses a kind of coupling bionic gradient energy absorption integrated automobile bumper and preparation method thereof, the bumper is six-layer composite structure with pangolin scale, porous cancellous bone and Wang Lian vein as bionic prototype, from outside to inside in turn bionic scale layer, subcutaneous flexible layer, cancellous bone transition layer, cancellous bone energy absorption layer, high-strength backplate layer and back vein reinforcing rib;The bionic scale layer is composed of a plurality of scale units Tile-like array, the cancellous bone transition layer and cancellous bone energy absorption layer have two-stage density gradient settings, and the back vein reinforcing rib is a multi-stage reinforcing rib structure, specifically including the radial vein reinforcing rib main rib that is radially and uniformly distributed from the central area of vein reinforcing rib to the periphery.Radial vein reinforcing rib main rib.The application integrates three biological prototypes in different hierarchical structures of bumper by coupling bionics, which can realize efficient load dispersion, gradient energy absorption characteristics, lightweight design and pedestrian safety protection.

The invention relates to the technical field of medical instruments, in particular to a three-screw-channel internal fixation interbody fusion cage which comprises an interbody fusion cage body, the interbody fusion cage body is of a polyhedral structure and is implanted into the lumbar intervertebral space through an anterior-lateral approach, and screw channels and connecting screw openings are formed in the front end position and the rear end position in the length direction of the interbody fusion cage body respectively; the screw channel is used for allowing screws to penetrate through the upper surface and the lower surface of the interbody fusion cage body, connected with the vertebral cancellous bone in a matched mode and fixed to the inner side of the lateral portion of the vertebral cancellous bone. The connecting screw is used for being connected with an installation instrument in a matched mode when the interbody fusion cage is implanted. By means of the screw channel, the fixing capacity of the interbody fusion cage can be effectively improved, better stability can be effectively provided for an OLIF operation through a proper implantation position and screw placement internal fixing operation, the occurrence risk of postoperative internal fixing related complications is effectively reduced, and the safety of the interbody fusion cage is improved. The effectiveness and the safety of the fusion cage in the lumbar vertebra front and outer side approach interbody fusion operation are improved.

The resettable anti-rotation implant is characterized in that the resettable anti-rotation implant comprises an outer sleeve and a pressurizing rotating shaft, a front screw hole and a rear screw hole are formed in the head and the tail of the outer sleeve respectively, and the thread directions of the front screw hole and the rear screw hole are opposite; the pressurizing rotating shaft is inserted into an inner hole of the outer sleeve and is in threaded connection with a front screw hole and a rear screw hole of the outer sleeve at the same time, a plurality of axial long grooves are formed in the front end of the outer sleeve in the circumferential direction of the outer sleeve and divide the outer sleeve into a plurality of expansion elastic pieces, and the expansion elastic pieces are expanded by rotating the pressurizing rotating shaft. The head and the tail of the outer sleeve horizontally move in the opposite directions at the same time, so that the expansion elastic pieces on the outer sleeve expand outwards at the same time, and the holding force of the outer sleeve on the femoral neck is increased. The femoral head cancellous bone repositor has higher holding force in the bone substance of the femoral head cancellous bone, and can be used for repositioning a fracture separation part in a rotating and push-pull manner.

The invention discloses a bone mineral density detection method and device based on a CT image and a storage medium, and relates to the technical field of medical image data processing. The method comprises the following steps: firstly, acquiring a scanning data sequence of a plain-scan CT covering a target vertebral body; and delineating the region of interest of the cancellous bone on a plurality of parallel layers of the same target vertebral body to reduce the influence of interference factors. Linear transformation is carried out according to the scanning data sequence, the HU value of each pixel in the region of interest is converted pixel by pixel, and the CT mean value of the target vertebral body is obtained based on the HU values. And then determining a relative bone mineral density index of the target vertebral body based on the CT mean value by taking a preset reference value as a benchmark. And finally, based on the relative bone mineral density index, performing bone mineral density grading according to a set threshold value to obtain an evaluation result corresponding to each target vertebral body. Therefore, the bone mineral density detection method is simple in process, low in cost and universal.

The application provides a bone layer identification method in hard bone tissue surgery, establishes a finite element simulation model of hard bone tissue surgery operation, carries out geometric modeling on the hard bone tissue, discretizes the hard bone tissue into finite element grids, defines material properties of the hard bone tissue, introduces constraint conditions of the operation process into the finite element model, obtains corresponding interactive force changes according to different parameters, collects real-time interactive force signals of the surgery tool and the hard bone tissue, selects multiple different types of bone layer features for the interactive force signals, then obtains force interaction curves through the finite element simulation model, establishes a Gaussian mixture model to describe distribution conditions of the different bone layer features, and trains the network model so that the network model can accurately identify different bone layers. The application solves the identification of the cortical bone and the cancellous bone in the hard bone tissue surgery process.

This application relates to the technical field of cancellous bone scaffolds, and discloses a method and apparatus for determining a reverse generation model of cancellous bone scaffolds based on topology optimization. In this method, the three-dimensional thin-layer structure is topology optimized to mimic the complex and irregular microstructural features of cancellous bone tissue. The first and second multi-channel mechanical contour maps represent force-related features. Multimodal data consisting of the three-dimensional thin-layer structure, the initial simplified model, the first multi-channel mechanical contour map, and the second multi-channel mechanical contour map are used as training samples to train a latent graph diffusion model. This allows the model to achieve powerful output performance for cancellous bone scaffolds under multimodal input conditions.

The utility model relates to the technical field of head taking devices, in particular to a femoral head taking device. In order to solve the problems that the drilling part of the head extractor is cancellous bone, the bone quality of the cancellous bone is not tough, the osteoporosis, the bone extraction efficiency is low, the bone extraction time is long, the operation risk is increased, and the secondary injury or pain is easily caused to a patient due to the fact that the proportion of the bone quality of the patient is low, the following technical scheme is provided: the head extractor comprises an operation handle, one end of the operating handle is in threaded connection with a connector, the connector is used for being drilled into a femoral bone, the operating handle comprises a rotating plate, one side of the rotating plate is fixedly connected with a connecting column, and the connector comprises a mounting cylinder which is in threaded connection with the end, away from the rotating plate, of the connecting column; the side, away from the rotating plate, of the mounting cylinder is fixedly connected with a connecting cylinder. According to the femoral head extractor, firm grabbing force can be provided after the femoral head extractor is drilled into the femoral bone, the complete femoral head is taken down, the instrument can be disinfected and reused, and the treatment cost is reduced.

A spine internal fixing device with a fusion function comprises a pedicle screw, the pedicle screw comprises a screw body, a screw tail is arranged at the upper end of the screw body, a nut is connected to the screw tail through internal threads, the screw body and the screw tail are of a honeycomb structure simulating cancellous bone, and solid external threads are arranged on the outer surface of the screw body. According to the spinal internal fixation device with the fusion function, a full-assembly simulation cancellous bone honeycomb structure of a pedicle screw rod nut and a matched connecting piece is prepared by adopting a 3D printing technology, and meanwhile, solid structures of key stress parts such as an external thread tip threaded connection surface are reserved so as to guarantee early mechanical fixation strength; after the components are assembled, a continuous bone ingrowth channel is formed, so that the transformation of internal fixation of the spine from temporary mechanical support to permanent osseous fusion is realized, and various intervertebral, intervertebral, posterior lateral and transverse process bone grafting fusion steps in a traditional spine fusion operation can be omitted.

A system for treating a basivertebral nerve in a vertebral body of a patient includes an introducer having a central channel and a steerable assembly sized for passable through the central channel. The introducer is configured to pass through the cortical bone of the vertebral body and into the cancellous bone of the vertebral body, and the steerable assembly has a first configuration and a deflected configuration. The steerable assembly includes an elongate member and a hypotube over a portion of the elongate member. The elongate member has a proximal end and a distal portion and is deflectable between the first configuration and the deflected configuration, and the hypotube has a proximal end and a distal end. The distal portion of the elongate member is configured to engage the distal end of the hypotube.

The application belongs to the technical field of biomedical materials and bone tissue engineering, and particularly relates to a preparation method of a blood-derived GeLMA-lignin biomimetic hydrogel scaffold. The method comprises the following steps: S1: preparing a GeLMA hydrogel precursor; S2: preparing lignin nanoparticles; S3: preparing PRF powder; S4: preparing LIG / PRF nanoparticles; and S5: preparing the blood-derived GeLMA-lignin biomimetic hydrogel scaffold. The single cold source ice mold technology of the application can control the pore direction, and the structure is similar to cancellous bone in height. The lignin nanoparticles realize the triple functions of mechanical enhancement, antioxidant protection and growth factor release. The PRF is derived from autologous blood, has the best physiological proportion and synergistic effect, and avoids the proportion imbalance and immune rejection possibly caused by the addition of exogenous factors. The single cold source process has strong controllability and has industrialization potential.

The embodiment of the invention provides a bone microstructure parameter extraction method, computing equipment, a computer readable storage medium and a computer program product. The bone microstructure parameter extraction method comprises the following steps: firstly, carrying out super-resolution reconstruction on a CT (Computed Tomography) image to enhance the image quality; then, a first bone mask is generated through a global threshold value, a local adaptive threshold value is constructed in combination with local gray statistical characteristics, and a mask edge and a low-contrast region are subjected to reclassification to obtain a more accurate second bone mask; and then, noise connected domain elimination under volume constraint is performed on the second bone mask, and a fracture or a pseudo joint of the bone trabecula network is repaired based on morphological characteristics to obtain a high-fidelity bone tissue structure segmentation result. And finally, cortical bones are removed from the result to separate out cancellous bones, and bone microstructure parameters are extracted from the cancellous bones. According to the technical scheme provided by the embodiment of the invention, the accuracy of bone microstructure parameter extraction is improved.

The invention relates to the technical field of preparation of pig-derived acellular matrix bone repair materials, in particular to a preparation method of a novel granular xenogeneic bone repair material, which comprises the following steps: S1, selecting pig bones without specific pathogens; s2, selecting limb epiphyseal cancellous bone parts of the pig; s3, cutting the pig bones selected in the step S2 into slices, strips and particles; s4, the cut pig bone particles are put into purified water to be ultrasonically stirred and cleaned, and fat in pores is removed; s5, soaking the cleaned pig bone particles in liquid nitrogen for 1-2 hours under sealing protection, and then putting the pig bone particles into purified water with the temperature of 25-37 DEG C to be repeatedly frozen and thawed; s6, sterilizing and degreasing the pig bone particles treated in the step S5; and S7, carrying out decellularization treatment on the pig bone particles treated in the step S6. Antigen components are removed through the processes of decellularization, degreasing, partial demineralization and the like, a natural porous structure is reserved, the porosity is close to that of human bones, efficient biocompatibility is achieved, and support is provided for development of clinical-grade medical materials.

The invention discloses a reverse expansion bolt for osteoporotic fracture fixation, which comprises an expansion sleeve, an anchoring mechanism for stabilization is arranged on the outer side of the expansion sleeve, the anchoring mechanism comprises a connecting assembly arranged on the outer side of the expansion sleeve, and an anti-falling assembly is further arranged on the outer side of the expansion sleeve; through the design of the wedge-shaped block capable of rotating and moving outwards and the elastic expansion valve formed by the expansion gap axially formed in the expansion sleeve, when the fixing nail is screwed, the wedge-shaped block precisely and spirally moves outwards along the inner wall of the expansion sleeve, the expansion valve is evenly expanded through the inclined face, radial controllable expansion is achieved, the expansion sleeve is tightly attached to the cancellous bone on the inner wall of a bone hole in a large area, and the effect of fixing the cancellous bone is achieved. Bone stress is dispersed, and bone cutting caused by local stress concentration is avoided; and meanwhile, the first anti-retreating teeth arranged on the outer side of the expansion sleeve and the anti-rotating teeth form a dual anti-falling and anti-rotating structure, so that the bolt is effectively prevented from axially retreating and circumferentially rotating in the skeleton.

The invention relates to a guiding self-centering spinal screw which comprises a screw body and is characterized in that the screw body is provided with a screw head, a centrum cancellous bone holding part, a vertebral pedicle cortical bone holding part and a tool operating part which are connected into a whole and are coaxially arranged, and the end of the screw head is of a convex spherical structure; the screw head part is connected with the centrum cancellous bone holding part into a whole through a connection transition part, and the connection transition part is provided with a concave arc opening which is arranged towards the axis direction of the screw body. In the implanting process, the screw can bear uniform and stable extrusion force on the periphery and cannot incline or deviate, so that the screw can be accurately implanted into a set screw channel and cannot deviate from the axis of the screw channel.

The invention discloses a TPMS-based bone scaffold topological structure for treating femoral head necrosis and an implantation method thereof, and relates to the field of bone scaffold topological structures. The stent comprises a stent main body structure, and the stent main body structure sequentially comprises a first stent cortical bone area, a stent cancellous bone area, a second stent cortical bone area and a stent'double cortical bone fixation 'femoral shaft penetrating area from top to bottom. The first stent cortical bone area, the stent cancellous bone area and the second stent cortical bone area are all subjected to structural topological optimization by utilizing TPMS. The invention provides a novel implantation mode by combining a three-period minimal curved surface (TPMS) topology optimization bone scaffold structure and fusing surface replacement and medullary core decompression, and solves the problems of insufficient mechanical support, poor structure biomimetic property, low implantation stability and the like of the existing bone scaffold. More accurate mechanical adaptation, better osseointegration effect and longer implant service life are achieved, so that caput femoris collapse is effectively delayed or avoided, and the requirement for artificial joint replacement is reduced.