Named after Friedrich Trendelenberg (1844-1924), the German surgeon who first described this position, this position is where the patient is placed with the head down on a table inclined at between 30 to 45 degrees with his/her legs hanging off the table.
This position is useful for, among other things, causing the intestines to fall out of the pelvis, making surgery on the pelvic structures easier, notably in gynaecological surgery.