Fig. 1

a Axial slice through the T8 vertebra showing x and y co-ordinate axes relative to the centroid of T1 b Thresholded axial slice at the same level - where A4 is the area of the torso, minus that of the lungs A1 (right lung) and A2 (left lung), A3 is the area of the total slice and (Xc,Yc) denotes the centroid of the cross-section. c Torso segment thickness (h) calculated from the reconstructed coronal image, where the segment height was taken from the midpoint of the superior vertebral endplate of each vertebra to the midpoint of the superior vertebral endplate of the level below including the IV disc. The distance between these two points was measured using the ImageJ ‘Segmented Line’ measuring tool