초록 ▼

A non-destructive and non-invasive method and apparatus determines the structural integrity of discrete pieces of material, such as bone, medical implants and structural parts by determining the impact ratio of a striking mass that impacts and rebounds from the material. The impact ratio is equal to

A non-destructive and non-invasive method and apparatus determines the structural integrity of discrete pieces of material, such as bone, medical implants and structural parts by determining the impact ratio of a striking mass that impacts and rebounds from the material. The impact ratio is equal to the ratio of instantaneous velocity of the striking mass immediately after the impact to the instantaneous velocity of the striking mass immediately prior to impact. A means can be used to force the striking mass towards the material to impact the material. In this case, the measured history of the displacement during the impact and the rebound are used to compute the impact ratio, the ratio being directly related to the impact reaction of the material. The impact ratio can be used to determine the structural integrity of the material or the onset of osteoporosis. The impact ratio can also be compared with previous measurements of the same piece of material or with standardized values of impact ratios to monitor changes in the impact reaction of the discrete piece of material for the diagnosis of incipient failure in the material and monitor the structural integrity of the piece of material.

대표청구항 ▼

[ What is claimed is:] [1.] A measuring device for non-invasively determining the loss in density of a discrete piece of biological tissue, said device comprising:a striking mass of known mass for impacting the said tissue, said striking mass having a maximum approach velocity V prior to impacting s

[ What is claimed is:] [1.] A measuring device for non-invasively determining the loss in density of a discrete piece of biological tissue, said device comprising:a striking mass of known mass for impacting the said tissue, said striking mass having a maximum approach velocity V prior to impacting said tissue and a maximum rebound velocity v after impacting said tissue; andmeans for determining an impact velocity ratio v/V of the maximum rebound velocity to the maximum approach velocity, the impact velocity ratio being indicative of the density of the tissue struck.