Novel anti-pullout pedicle screw based on additive manufacturing technology

Abstract

The invention discloses a novel anti-pullout pedicle screw based on the additive manufacturing technology, which is high in strength and capable of promoting osseointegration. The pedicle screw is composed of a solid nail lower end with a thread, a nail upper end with a peripheral tensile expansion structure and an internal solid cylinder, and a nail base connected with the peripheral tensile expansion structure, as is shown in Figure 1. With the tensile expansion performance of the tensile expansion structure, the pedicle screw expands when tensioned, and thus the stability of the pedicle screw and the vertebral body is improved; meanwhile, the tensile expansion structure part is of a porous structure, and osteocytes can grow into the porous structure easily to promote osseointegration and accelerate integration of the pedicle screw and the vertebral body; besides, unique structural design is adopted to overcome the defect of low strength of the tensile expansion structure, so that the mechanical strength of the pedicle screw is ensured and the internal fixation effect is improved while the anti-pullout performance of the pedicle screw is achieved. The pedicle screw can be easilyapplied to design of orthopedic medical instruments.

Description

technical field [0001] The invention is applied in the field of orthopedic medical devices, and in particular relates to a novel pull-out-resistant pedicle screw. Background technique [0002] Pedicle screw is a minimally invasive orthopedic internal fixation medical device for the treatment of unstable fractures and dislocations of the thoracolumbar spine or combined with paraplegia, spinal deformities, and spinal tumors. However, in daily life, the pedicle screw often loosens or falls out under the action of the internal mechanical environment, leading to internal fixation failure. At present, the expansion nail can be inserted with a small diameter, and after entering the nail hole, the corresponding operation is performed to expand the diameter of the nail, so that the screw rod and the component can be firmly connected to achieve stable fixation, but the diameter of this type of expansion nail becomes larger after implantation in bone tissue, resulting in bone loss. Ex...

AI Technical Summary

Problems solved by technology

However, in daily life, the pedicle screw often loosens or falls out under the action of the internal mechanical environment, resulting in internal fixation failure.

At present, the expansion nail can be inserted with a small diameter, and after entering the nail hole, the corresponding operation is performed to expand the diameter of the nail, so that the screw rod and the component can be firmly connected to achieve stable fixation, but the diameter of this type of expansion nail becomes larger after implantation in bone tissue, resulting in bone loss. Excessive local pressure on the tissue, bone resorption occurs, and eventually leads to screw loosening

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