Stress–strain index
The stress–strain index, of a bone, is a surrogate measure of bone strength determined from a cross-sectional scan by QCT or pQCT. The stress–strain index is used to compare the structural parameters determined by analysis of QCT/pQCT cross-sectional scans to the results of three point bending test.Definition
It is calculated using the following formula:
Where:
It was developed by the manufacturer of a peripheral quantitative CT scanner, and is considered to be by some an improvement over the information provided by calculating the area moments of inertia and polar moments of inertia.
