106results about How to "Avoid stress shielding" patented technology

An interbody spinal implant is formed of cortical bone adapted for placement across an intervertebral space formed across the height of a disc space between two adjacent vertebral bodies. An asymmetrical leading end on the implant is adapted to sit upon the peripheral areas, such as the apophyseal rim and the apophyseal rim area, of the vertebral end plate region of the vertebral bodies without protruding therefrom. The asymmetrical leading end allows for the safe use of an implant of maximum length for the implantation space into which it is installed. The implant can also include an asymmetric trailing end adapted to sit upon the more peripheral areas of the vertebral end plate region of the vertebral bodies.

Spinal spacers 20 are provided for fusion of a motion segment. The spacers include a load bearing member 21 having a wall 22 sized for engagement within a space between adjacent vertebrae to maintain the space and an effective amount of an osteogenic composition to stimulate osteoinduction. The osteogenic composition includes a substantially pure osteogenic factor in, a pharmaceutically acceptable carrier. In one embodiment the load bearing member includes a bone graft impregnated in an osteogenic composition. In another embodiment, the osteogenic composition 30 is packed within a chamber 25 defined in the graft. Any suitable configuration of a bone graft is contemplated, including bone dowels, D-shaped spacers and cortical rings. A spinal spacer 300 for engagement between vertebrae is also provided which includes a body 301 formed of a bone composition. The body 301 includes a first end 311, an opposite second 315 end, a superior face 335 defining a superior vertebral engaging surface 337 and an inferior face 338 defining an inferior vertebral engaging surface 340. At least one of the vertebral engaging surfaces defines a set of migration resistance grooves 350. Each of the grooves 350 includes a first face 355 defining an angle of no more than about 90 degrees relative to the engaging surface 340 and a second opposing sloped face 360. The first and second faces 355, 360 define an arcuate pocket 370 therebetween for trapping vertebral bone to resist migration of the spacer 300. In one embodiment, the grooves 350 are arranged in series in that all of the second faces 360 slope in the same direction.

The invention discloses a medical titanium/magnesium composite material which comprises a porous skeleton, wherein the porous skeleton is prepared from medical-grade titanium wires or titanium alloy wires and prepared into a preset shape and a preset porosity by using a conventional winding or knitting machine, the porous skeleton is filled with three-dimensional through pores with different porosities capable of meeting various bone implantation requirements, then a medical magnesium or magnesium alloy melt is infiltrated in the pores of the porous skeleton by pressureless infiltration or negative-pressure suction casting, and after the porous skeleton is cooled, a medical titanium/magnesium composite material is formed. The composite material disclosed by the invention is reasonable in structure and excellent in mechanical properties; in the early stage of body implantation, the mechanical properties of the composite material can be matched with bones well, thereby avoiding stress shielding; after the composite material is implanted, with the degradation of magnesium, a porous structure of an implant is constantly restored, so that bone conduction is facilitated, and the requirements of most of bone filling, bone repair and bone transplantation applications can be met, therefore, the composite material is applicable to bone implanting operations with relatively high strength requirements.

The invention relates to a 3D-printed porous tantalum metal bone plate. The 3D-printed porous tantalum metal bone plate is characterized in that tantalum metal powder is taken as a base material, andthe bone-imitating trabecular bone plate having bone induction property and produced by 3D printing has an interconnecting-pore structure fit for bone growth. The production method includes: under argon production, using medical grade spherical tantalum powder as a raw material to produce the porous bone plate by 3D printing; removing excess metal powder adhering to the surface of the bone plate through sandblasting; removing residual stress through heat treatment to make the surface of the bone plate smooth. By the arrangement, the porous bone plate with the bone induction property can form excellent bone integration with bone tissue so as to achieve permanent fixation in biology.

The invention discloses a metal bone trabecula. The metal bone trabecula comprises at least three crossed metal bone trabecula supports, a micro-topological grid structure is embedded into the metal bone trabecula, and at least three intersection points are formed between the micro-topological grid structure and the metal bone trabecula supports. The bone trabecula is formed by regularly or irregularly arranging hollowed-out unit structure bodies in a three-dimensional space, the weight reducing effect is obvious, meanwhile, the requirement of rigidity and strength of different areas of partscan be met at the same time, stress shielding is avoided, and good matching of high strength and high weight reduction ratio can be achieved; in addition, after growing into the bone trabecula structure comprising a micro-topological grid, human body sclerotin can be fused with bone, bone ingrow can be induced to the largest extent, and accordingly long-term biological fixation of a prosthesis canbe achieved. Meanwhile, the invention further discloses a bone implant comprising the metal bone trabecula. The bone implant can achieve personalized customization through 3D printing, the process issimplified, and the economic cost is greatly reduced.

The invention relates to a preparation method of titanium foams for cancellous bone. The preparation method comprises the following steps of: (1) mixing raw materials, namely selecting a primary mixture which is obtained by uniformly mixing titanium powder and a pore forming agent in a grinding body, wherein the mass part ratio of the titanium powder to the pore forming agent is (42.8-48.2):(52.8-58.2); (2) carrying out one-direction pressing on the primary mixture by adopting a universal material testing machine to prepare a green pressing body, wherein the one-direction pressure is 200-250MPa, and the pressure holding time is 1 minute; and (3) putting the green pressing body into a vacuum carbon tube furnace, sintering the green pressing body for 2 hours at 1200-1300 DEG C in an argon protective atmosphere to ensure that the pore forming agent is removed, and finally cooling along with the furnace to obtain the titanium foams. According to the titanium foams prepared by using the preparation method, the Young modulus is matched with that of the cancellous bone of the human body, therefore the stress shielding phenomenon is effectively avoided, and an implant can be permanently fixed; and meanwhile, the titanium foams can be prevented from being oxidized as far as possible by adopting the argon protective atmosphere.

The invention relates to a pressure-adjustable combined-type outer fixing support for clinical orthopedic application. Combining forms of the pressure-adjustable combined-type outer fixing support include a single arm type, a semi-ring type and a ring type, fixing clamping blocks include knitting needle clamping blocks and knitting rod clamping blocks, a pressure-adjustable fixing arm is composed of an adjusting shaft, a sliding fit thread sleeve, an elastic device, a connecting nut, a fastening nut and a fixing rod, the sliding fit thread sleeve is radially provided with a limiting pin, a limiting jack screw, a pressure adjusting pin, an outer ferrule, an inner ferrule, a pressure adjusting nut and a pressure adjusting pin hole, the adjusting shaft is in sliding fit with the sliding fit thread sleeve, the connecting nut is in threaded connection with the sliding fit thread sleeve and the fastening nut, the fastening nut and a pipe clamping pin are in relatively fixed fit, the elastic device is composed of a spring or an elastic capsule, a pressure sensor, a sliding base, a pressure sensor connecting device and a pressure displayer and can be provided with a piezometer or not. The pressure-adjustable combined-type outer fixing support can transmit stress to enable stress to be generated at a fracture end, stress shielding can be avoided, and delayed fracture healing and fracture disunion are prevented.

The disclosed composite scaffold provides a highly porous and flexible structure that substantially maintains its three-dimensional shape under tension and provides mechanical reinforcement of the repair or reconstruction-first via scaffold mechanical properties, and subsequently, through newly regenerated functional tissue as the scaffold is resorbed.

Spinal spacers 20 are provided for fusion of a motion segment. The spacers include a load bearing member 21 having a wall 22 sized for engagement within a space between adjacent vertebrae to maintain the space and an effective amount of an osteogenic composition to stimulate osteoinduction. The osteogenic composition includes a substantially pure osteogenic factor in a pharmaceutically acceptable carrier. In one embodiment the load bearing member includes a hone graft impregnated in an osteogenic composition. In another embodiment, the osteogenic composition 30 is packed within a chamber 25 defined in the graft. Any suitable configuration of a bone graft is contemplated, including bone dowels, D-shaped spacers and cortical rings.

A spinal column fusion device internally lined with reinforced ribs comprises a main body structure and two internally-lined metal reinforced rib structure bodies embedded in the main body structure, wherein the main body structure is of a tubular structure with two hollow holes, each internally-lined metal reinforced rib structure body comprises a metal connecting bridge and two cylinders with internal thread structures, the two cylinders are connected by the metal connecting bridge, and the connecting bridge is embedded in a tube wall of the tubular structure. The horizontal section of the fusion device imitates a spinal column anatomical structure, the whole strength and toughness of the fusion device are improved by a form of internally-lined reinforced ribs, and the selecting range of novel biological materials is enlarged. In the process of an implantation operation, the main body part borne by the internally-lined metal reinforced rib structure is implanted into a body, so thatthe situation that the fusion device can be damaged due to a bad mechanics environment during the operation to influence an operation success can be avoided.

The invention discloses a bionic bone joint based on curved surface 3D printing and a preparation method thereof. The multilayer bionic joint is formed by an inner layer, a middle layer and an outer layer which are in close contact in sequence, wherein the inner layer is a porous tantalum metal support, the middle layer is a solid biological ceramic support, the outer layer is a solid gelatin/ sodium alginate composite hydrogel support, the inner layer, the middle layer and the outer layer are all of an arc-shaped shell structure, the radian of the arc-shaped shell is 120-240 degrees, and a cell loading cavity formed by continuous or discontinuous edges formed by protruding outwards from the surface of the outer layer and grooves formed between the edges is formed in the surface of the outer layer. The multilayer bionic joint is large in arc surface radian and suitable for repairing large-area osteochondral joint defects, and the repairing area can be larger than 1/2 of the area of thewhole joint. Cells are inoculated into the cell loading cavity, so that the adhesion rate of the cells is increased, and the problem that the surface of the outer layer of the bionic joint is smooth,so that the inoculated cells are not prone to adhesion is solved.

The invention discloses a metal trabecular bone, which comprises at least three intersecting metal trabecular supports, and a micro-topological grid structure is embedded in the metal trabecular bone, and the micro-topological grid structure is connected with the metal bone trabecular The trabecular support has at least three intersections, and part of the outer surface of the metal trabecular is provided with a bone trabecular coating. The trabecular bone of the present invention is formed by regular or irregular arrays of hollowed-out unit structures in three-dimensional space, which not only has an obvious weight-reducing effect, but also satisfies the stiffness and strength of different parts of the parts at the same time, avoiding stress shielding, Achieve a good match of high strength and high weight loss ratio; in addition, human bone grows into the trabecular bone structure and can be integrated with the bone, so that the trabecular bone prosthesis can be firmly combined with the bone bed, and can Induce bone ingrowth to the greatest extent so as to achieve long-term biological fixation of the prosthesis. At the same time, the invention also discloses a bone implant comprising the metal bone trabecular.

The invention relates to an elastic spine fixing system and pressure-adjustable fixing rods for clinical application of a department of orthopedics. The elastic spine fixing system comprises any two of the pressure-adjustable fixing rods, two connecting cross rods (50), four fixed hooks (51) and a plurality of pedicle screws (46); each of the adjustable pressure fixing rods comprises an adjusting rod, a sliding fit thread sleeve, an elastic device and a fixed rod. The elastic spine fixing system and the pressure-adjustable fixing rods provided by the invention have the advantages that the pressure is adjustable, fixing is firm, the operation is simple, the adjustment is easy, stress shielding is effectively prevented, osteoporosis is avoided, and fracture healing is accelerated.