Foramen magnum
The foramen magnum (Latin, big hole ') or Large foramen magnum ( Synonym: foramen magnum ) is the largest opening at the base of the skull and is made from occiput. His rear center is called opisthion and serves as an anatomical landmark for skull measurements.
The foramen magnum is passage point for the central nervous system (CNS): Here the spinal cord and brain merge. The adjacent to the spinal cord part of the brain called the medulla oblongata (, medulla '). The spinal roots of XI. Cranial nerve ( accessory nerve ), the vertebral artery ( vertebral artery ) and a venous plexus use the foramen magnum as a passage opening.