5results about How to "Reduce stress shielding effect" patented technology

The invention provides a bionic 3D printing degradable magnesium alloy interbody fusion cage and a preparation method thereof, the bionic 3D printing degradable magnesium alloy interbody fusion cage comprises a porous frame and a through hole net rack, the porous frame is constructed by supporting rods with the diameter of about 0.4 mm, the porous frame is of a compact rhombic hole structure, the aperture is about 200-400 microns, the pore coverage rate is about 50%-80%, and a horseshoe-shaped columnar space is defined; the through-hole net rack is formed by building supporting rods with the diameter of 0.2-0.1 mm, the hole diameter is about 300-800 microns, the hole coverage rate is about 90%, a dome structure is formed in the center, and the through-hole net rack is arranged in the middle of the porous frame. The magnesium-strontium alloy is adopted as a base material of the interbody fusion cage, the interbody fusion cage is integrally formed through the 3D printing technology, and the degradable characteristic and good biocompatibility of the magnesium alloy are fully utilized. The elasticity modulus of the magnesium alloy is closer to that of the human bone tissue, physiological loads can be better shared and transmitted, the stress shielding effect is reduced, and growth and fusion of the bone tissue are promoted.

The present invention discloses a support rod for femoral head necrosis, characterized in that it comprises a head section rod and a tail section rod, the center of the head section rod is provided with a head section inner hole, the center of the tail section rod is provided with a tail section inner hole, the outer side wall of the tail section rod is provided with a first external thread, the outer side wall of the head section rod is provided with a first spiral groove, the inner side wall of the head section rod is provided with a first radial hole, and the first radial hole connects the first spiral groove with the head section inner hole. The present invention can provide sufficient support strength, and at the same time, in the early stage of implantation, all tissue fluid that causes increased internal pressure in the femoral head can flow out of the bone, and in the later stage of implantation, a certain space can be reserved for the growth of new bone cells, so that the patient can avoid femoral head collapse when walking normally, which is conducive to the growth of bone tissue and close combination with the support rod to increase mechanical properties. In addition, the present invention also discloses a method of use.

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.

The utility model discloses a skull repairing mesh plate, and relates to the technical field of medical implants, the skull repairing mesh plate comprises a mesh plate main body, the mesh plate main body has a curved surface shape matched with a skull defect area; the screen plate main body is made of a composite material of polyether-ether-ketone and biphase calcium phosphate; the mesh plate main body comprises a compact area and a loose area, and the porosity of the compact area is smaller than that of the loose area; every two adjacent loose areas are separated through the corresponding dense areas, and the dense areas are staggered to form a net-shaped structure. First micropores are formed in the surface of the loose area; first through holes are formed in the compact area at intervals, and the first through holes are formed in the thickness direction of the screen plate body in a penetrating mode. The skull repairing screen plate has good mechanical properties; the bone integration capability is good; due to the lightweight design, foreign body sensation after implantation is reduced; the occurrence rate of subcutaneous hydrops can be reduced.

This invention discloses a femoral prosthesis for the hip joint, belonging to the field of medical device technology. The femoral prosthesis includes a femoral stem and a femoral head movably connected to the femoral stem. The femoral stem includes a rigid stem neck and a flexible stem body. The rigid stem neck and the flexible stem body are detachably connected. One end of the rigid stem neck is movably connected to the femoral head, and the other end is connected to the flexible stem body. By dividing the femoral stem structure into a rigid stem neck and a flexible stem body, and adopting a detachable connection method, the femoral stem forms a longitudinal mechanical partition structure. This reduces the overall stiffness of the stem body while ensuring the strength of the neck, improving the load transfer mode, and reducing stress shielding effects.