Scalar-Weighted PCA

Hello,
I am looking at Foot CT scans. I have segmented each bone. I would like to compute the PCA axes of each bone, WEIGHTED with the scalar value of the voxels contained/overlapping each bone model. So the value for each voxel would be [HU*(x,y,z)]. Is there any way to do that using the quantifying module or some other way ? Label map statistics seem to only take into account spatial data and scalar statistics only give min, max, mean, median, sd values for the considered segment.
Thank you !