Cranial osteopathy: Cranial nerves
Page created: March 18, 2021
Notes
Osteopathic cranial manipulative medicine
Cranial osteopathy: Cranial nerves
| CRANIAL NERVES | |||||||||||
| CRANIAL NERVE | FUNCTION | EXITS SKULL AT: | BONES INVOLVED IN SD* | ||||||||
| I (1): Olfactory | Smell | Cribriform plate | Sphenoid, Frontal, Ethmoid | ||||||||
| II (2): Optic | Vision | Optic foramen | Sphenoid, Occiput | ||||||||
| III (3): Oculomotor | Innervates muscles of eye movements and levator palpebrae superioris muscle; Pupillary constriction and accommodation | Superior orbital fissure | Sphenoid, Temporal | ||||||||
| IV (4): Trochlear | Innervates superior oblique muscle | Superior orbital fissure | Sphenoid, Temporal | ||||||||
| V (5): Trigeminal | Sensation of the face, mouth, and cornea; Innervates the muscles of mastication | V1: superior orbital fissure V2: foramen rotundum V3: foramen ovale | V1: sphenoid, temporal V2: sphenoid, temporal V3: sphenoid | ||||||||
| VI (6): Abducens | Innervates lateral rectus muscle | Superior orbital fissure | Sphenoid, Temporal | ||||||||
| VII (7): Facial | Sensory taste of the anterior ⅔ of tongue; Innervates the muscles of facial expression, stapedius muscle, and lacrimal and salivary glands | Stylomastoid foramen | Sphenoid, Temporal, Occiput | ||||||||
| VIII (8): Vestibulocochlear | Sense of hearing and balance | Internal auditory meatus | Sphenoid, Temporal, Occiput | ||||||||
| IX (9): Glossopharyngeal | Sensory taste of the posterior ⅓ of tongue; Carotid baroreceptors and chemoreceptors; Innervates the salivary glands; Gag reflex | Jugular foramen | Temporal, Occiput | ||||||||
| X (10): Vagus | Parasympathetic autonomic function to the heart, GI tract (up to the splenic flexure); Sensation of the larynx and pharynx; Innervates the muscles of vocal cords; Gag reflex | Jugular foramen | Temporal, Occiput, OA joint, AA joint, C2 | ||||||||
| XI (11): Accessory | Innervates the sternocleidomastoid and trapezius muscles | Jugular foramen | Temporal, Occiput | ||||||||
| XII (12): Hypoglossal | Innervates muscles of the tongue | Hypoglossal canal | Condylar compression at occiput | ||||||||
* SD = somatic dysfunction
| SIGNS & SYMPTOMS OF CRANIAL NERVE DYSFUNCTION | |||||||||||
| CRANIAL NERVE | FUNCTION | SYMPTOMS OF DYSFUNCTION | SIGNS OF DYSFUNCTION | ||||||||
| I (1): Olfactory | Smell | Anosmia | Cannot smell strong scents (e.g., coffee) | ||||||||
| II (2): Optic | Vision | Decreased vision / blindness | Abnormal pupillary light reflex | ||||||||
| III (3): Oculomotor | Innervates muscles of eye movements and levator palpebrae superioris muscle; pupillary constriction and accommodation | Blurry vision / diplopia | Ptosis, abnormal pupillary light reflex, abnormal extraocular movements | ||||||||
| IV (4): Trochlear | Innervates superior oblique muscle | Diplopia | Contralateral head tilt (to balance line of vision), abnormal extraocular movements | ||||||||
| V (5): Trigeminal | Sensation of the face, mouth, and cornea; innervates the muscles of mastication | Dry eyes, difficulty chewing, decreased sensation on face | Asymmetric jaw closing | ||||||||
| VI (6): Abducens | Innervates lateral rectus muscle | Diplopia | Ipsilateral head tilt (to balance line of vision), abnormal extraocular movements | ||||||||
| VII (7): Facial | Sensory taste of the anterior ⅔ of tongue; innervates the muscles of facial expression, stapedius muscle, and lacrimal and salivary glands | Hyperacusis, dry eyes, dry mouth, loss of taste on anterior ⅔ of tongue | Facial asymmetry (wrinkling forehead, smiling) | ||||||||
| VIII (8): Vestibulocochlear | Sense of hearing and balance | Decreased hearing / deafness; vertigo | Abnormal Weber / Rinne tests | ||||||||
| IX (9): Glossopharyngeal | Sensory taste of the posterior ⅓ of tongue; carotid baroreceptors and chemoreceptors; innervates the salivary glands; gag reflex | Dysphagia, dry mouth, loss of taste on posterior ⅓ of tongue | Absent gag reflex | ||||||||
| X (10): Vagus | Parasympathetic autonomic function to the heart, GI tract (up to the splenic flexure); sensation of the larynx and pharynx; innervates the muscles of vocal cords; gag reflex | Hoarseness, dysphagia | Sagging palate | ||||||||
| XI (11): Accessory | Innervates the sternocleidomastoid and trapezius muscles | Shoulder weakness | Weakness shrugging shoulders or turning head to ipsilateral side | ||||||||
| XII (12): Hypoglossal | Innervates muscles of the tongue | Dysarthria | Tongue cannot protrude midline | ||||||||
Author: Arman Israelyan, OMS-III
Author: Matt Lipinski, DO
Editor: Robyn Hughes, MScBMC