cervical spinal nerve 1 cervical spinal nerve 1 the cervical spinal nerve 1 (c1) is a spinal nerve of the cervical segment. c1 carries predominantly motor fibres, but also a small meningeal branch that supplies sensation to parts of the dura around the foramen magnum (via dorsal rami). cervical spinal nervethe plan of the cervical and brachial plexusesthe spinal cord with spinal nervesdetailsidentifierslatinnervi spinalisfma6440anatomical terminology it originates from the spinal column from above the cervical vertebra 1 (c1). the dorsal root and ganglion of the first cervical nerve may be rudimentary or entirely absent. muscles innervated by this nerve are: geniohyoid muscle- through hypoglossal nerve rectus capitis anterior muscle longus capitis muscle (partly) rectus capitis lateralis muscle splenius cervicis muscle (partly) rectus capitis posterior major muscle levator scapulae muscle (partly) thyrohyoid muscle – through hypoglossal nerve omohyoid – through ansa cervicalis sternohyoid – through ansa cervicalis