I have a data set in which cross-sectional properties on bones were derived from CTs in BoneJ and that includes section moduli around A-P and M-L anatomical planes. This dataset is complemented with data from literature which include only moments of area (inertia) and external dimensions (AP and ML diameters). I need to calculate section moduli for this subset as well. Is the general formula, e.g. Ix/(APdiameter/2) for such calculations adequate? When I tried to compare section moduli calculated by boneJ and by this general formula on my CT derived sample, the values were significantly different. Is there any other way? I work with human femora, specifically subtrochanteric level which is not very circular.
Thanks for any help