a porous metal rod

Abstract

A porous metallic bar is made of a porous metallic material. The porous metallic bar includes two portions; one portion is a circular bar-shaped portion, and the other portion connected to the circular bar-shaped portion is a thread portion; threads are arranged on an outer part of the thread portion; the outer diameter of the threads is greater than the inner diameter of the circular bar-shaped portion; the porous metallic material is a hierarchical pore metallic material; a hierarchical pore metallic material body includes all levels of pore cavities which are graded according to the material pore size, and all levels of cavity walls forming the pore cavities; cavity walls of upper level pore cavities formed by three-dimensional spaces are made of a lower level porous metallic material; pore cavities at each level communicate with each other and all levels of pore cavities communicate with each other; and the number of levels is at least two. The porous metallic bar allows tissues to overgrow in the inner part of an implant body, tight fusion between the implant body and a thighbone can be achieved, the interface is stable and firm, loosening can be avoided, pain of a patient can be avoided, and the time of artificial hip joint replacement is delayed.

Description

technical field [0001] The invention relates to the field of prostheses, in particular to a medically implanted porous metal rod for treating early necrosis of the femoral head. Background technique [0002] Femoral head necrosis is a chronic progressive disease. It is caused by various reasons, such as ischemia, necrosis, trabecular fracture, and femoral head collapse. The main clinical manifestations are hip joint pain and dysfunction, and the disability rate is high. . There are more than 20 million patients with osteonecrosis of the femoral head in the world, of which 5-7.5 million are in my country. [0003] There are many treatment methods for adult osteonecrosis of the femoral head, each with its own advantages and disadvantages. When the disease develops to the stage of joint damage, artificial hip replacement is required. However, artificial hip replacement has many disadvantages such as infection, loosening, dislocation, and wear. Especially for young patients, d...

AI Technical Summary

Problems solved by technology

However, the porous material used in the porous tantalum rod is a material with a single void, and the cavity wall of the hole is still a dense material. After the porous tantalum rod is implanted, when the force is applied, although the overall elastic modulus of the material is low, it acts as a cavity. Due to the large elastic modulus of the dense material of the wall, it is difficult for the cells on the cavity wall of the porous material to feel the stimulation of the force, and stress shielding occurs, which is not conducive to cell growth, and is not conducive to the fusion of the implant and the femur. The growth factors and other drugs carried by the cavity wall of the dense material are limited, which is not conducive to the realization of bone tissue regeneration; further research has found that porous tantalum prepared by chemical vapor deposition of a single void is used as a bone implant, and bone tissue grows into the implant. The depth is less than 3mm, which makes the interface between the implant and the adjacent bone tissue unstable and loose, which affects the treatment effect

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