Tuesday, February 01, 2011

US Patent 7878988 - Measurement of bone healing using nanotubes


This patent teaches using carbon nanotubes as stress/strain sensors to access the healing of bone damage. Claim 1 reads:

1. A method of measuring bone healing strength on a bone area being studied, comprising:

a) implanting a bone fixation device constituted at least in part of a material selected from the group consisting of carbon nanotubes and other high aspect ratio materials which alter the conduction of electric current when said bone fixation device is subjected to stress or strain;

b) applying externally a testing cuff requiring no direct electric contacts to said bone fixation device, wherein said testing cuff provides a means to cause an electric current in said bone fixation device, and to measure said electric current;

c) using an analyzer to study changes in said electric current resulting from the effects of stress and strain on the material of the bone fixation device;

d) obtaining a series of test results using predetermined loads on the bone area; and

e) determining bone healing strength.