Median sacral a.

The median sacral artery is a small vessel that arises posterior to the abdominal aorta and superior to its bifurcation.

It descends in the middle line in front of the fourth and fifth lumbar vertebræ, the sacrum and coccyx, ending in the glomus coccygeum (coccygeal gland). From it minute branches pass to the posterior surface of the rectum. On the last lumbar vertebra it anastomoses with the lumbar branch of the iliolumbar artery; in front of the sacrum it anastomoses with the lateral sacral arteries, sending offshoots into the anterior sacral foramina.