On the superior surface of the first (lumbarized) sacral vertebra pedicles, between the vertebral body and superior articular processes, lie the shallow superior vertebral notches.  Together with the inferior vertebral notches of L5, they form the L5/S1 intervertebral foramina.  Each foramen transmits the fifth lumbar spinal nerve and its coverings, spinal arteries, venous plexuses and recurrent meningeal (sinu-vertebral) nerves.  Further, the L5 dorsal root ganglia lie partly in the foramina.