Phrenic nerveBrachial plexus(C5 to T1)Cervical plexus(C1 to C4)Cutaneous nervesAnsa cervicalis tostrap musclesAC3C4C2C2C3C4Ophthalmic nerve [V1]Trigeminal nerve [V]Maxillary nerve [V2]Mandibular nerve [V3]Anterior rami (C2 to C4) ClavicleAcromionPosterior rami (C2 to C4)External occipital protuberanceB