<p>Measurements were performed at three levels in the C4, C5 and C6 vertebral bodies. The axial CT images were reconstructed to planes parallel to the endplate. (A) Sagittal CT image from a 69 year old male. The illustration (B) shows the three levels (C4, C5, C6) and three transverse locations at C5 (1, 2, 3) that were used for the measurements in the axial plane. The dashed line 1 shows the level adjacent to the cranial endplate, line 2 the mid-vertebral level and line 3 the level adjacent to the caudal endplate. The same approach (using the three lines for the transversal levels) was also used for the C4 and C6 vertebral body.</p