The transverse processes of C1 (atlas) are longer than in other cervical vertebrae (except those of C7) and act as long levers.  The broad flat apex represents the posterior tubercle of a typical cervical vertebra.  Close to the lateral mass is the foramen transversarium that transmits the vertebral vessels and associated sympathetic plexus.  Several muscles attach to the transverse processes of C1.  Obliquus capitis superior and rectus capitis lateralis attach superiorly to the transverse processes, with the latter displaying a more anterior site of attachment than the former.  Laterally, obliquus capitis inferior attaches to the apex, and scalenus medius, splenius cervicis and levator scapulae (antero-posteriorly) attach to the inferior surface.