3D MRI, Coronal Neutral Sequence (top) compared to the Coronal Abduction External Rotation (AER) Sequence (bottom)

The images were selected to compared the landmark anatomy when the arms are at the side (neutral, top) as compared to arms overhead (AER, bottom). Observe the close proximity of the clavicles (C) and subclavius muscles (SUB) to the axillary arteries (AX) in the bottom image as compared to top image.

A few labels have been placed on the image to assist with identification of landmark anatomy. The trachea (T), esophagus (E), subclavius muscles (SUB), anterior scalene muscles (AS), external jugular veins (XJ), internal jugular veins (J), axillary arteries (AX), common carotid arteries (CC), brachiocephalic vein (BRV), musculocutenous nerve (MU), ulnar nerve (UL), middle chord (MC) of the brachial plexus, right lung (RL), and left lung (LL) are labeled for reference. The aorta (A) and pulmonary artery (P) are labeled to identify the heart.