Change in the z-axis location of the sternal notch in an arms-raised vs arms-down position on CT examinations

The aim of the study was to determine whether the sternal notch changes in its z-axis position in the arms raised vs arms down position on CT scans. A retrospective study was made of 132 consecutive CT scans of the neck and chest. We recorded the table position of the sternal notch and the most inferior slice through the thyroid gland on both scans, and the table position on the chest CT where the configuration of the head and neck vessels most closely corresponded to their configuration on the sternal notch slice of the neck CT. The sternal notch moved up an average of 8.4 mm (p or =10 mm. In 6% of cases, the sternal notch moved upwards > or =20 mm. There was a slightly greater upward movement of the sternum in males of 2.57 mm (p = 0.0208). Mean upward motion of the sternal notch relative to the vessels was 7.74 mm (p