The lithotomy position is a common position for surgical procedures and medical examinations involving the pelvis and lower abdomen, as well as a common position for childbirth in Western nations. The lithotomy position involves the positioning of an individual's feet above or at the same level as the hips (often in stirrups), with the perineum positioned at the edge of an examination table. References to the position have been found in some of the oldest known medical documents including versions of the Hippocratic oath (see lithotomy); the position is named after the ancient surgical procedure for removing kidney stones and bladder stones via the perineum. The position is perhaps most recognizable as the 'often used' position for childbirth: the patient is laid on the back with knees bent, positioned above the hips, and spread apart through the use of stirrups.