Closed loop obstruction is a phenomenon characterized by obstruction of the bowel at two points. The obstruction usually occurs secondary to adhesions, herniation, or volvulus. Reference: https://radiologyassistant.nl/abdomen/bowel/closed-loop-in-small-bowel-obstruction#:~:text=Closed%20loop%20obstruction%20is%20a,is%20known%20as%20a%20volvulus. Image via: https://www.sciencedirect.com/science/article/pii/S2211568413003318