Elbows and shoulders are rotated anteriorly. A PA chest projection with accurate positioning demonstrates 1. 10 or 11 posterior ribs.
1 : a position assumed in lying down the dorsal decubitus. 2a : ulcer. b : bedsore. 3 : prolonged lying down (as in bed)
The lateral decubitus position provides surgical exposure to the chest, retroperitoneum, hip, and lateral leg. Common procedures performed in this position include procedures on the lung, aorta, kidney, and hip.
Learn more about decubitus here: