inferior duodenal flexure

It passes inferiorly to the lower border of vertebral body L3, before making a sharp turn medially into the inferior duodenal flexure (the end of the descending part).

The third (inferior/horizontal) part of the duodenum begins at the inferior duodenal flexure and passes transversely to the left, crossing the right ureter, right testicular/ovarian vessels, inferior vena cava, abdominal aorta and the vertebral column.