Anatomy of the Muscles of the Head and Neck

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Muscles of the Head and Neck - Listed Alphabetically
Muscle	Origin	Insertion	Action	Innervation	Artery	Notes
anterior scalene	anterior tubercles of the transverse processes of vertebrae C3-C6	scalene tubercle of the first rib	elevates the first rib; flexes and laterally bends the neck	brachial plexus, C5-C7	ascending cervical a., a branch of the thyrocervical trunk	a muscle of inspiration; an important landmark of the neck; it is located between the subclavian vein and the subclavian artery; the roots of the brachial plexus pass posterior to it; the phrenic nerve crosses its anterior surface (Greek, scalene = uneven)
aryepiglottic	apex (superior part) of the arytenoid cartilage	epiglottis	draws the epiglottis posteriorly and downward during swallowing	inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the of vagus (X)	laryngeal br. of the superior thyroid a.	the mucosa is raised by the underlying aryepiglottic m. to form the aryepiglottic fold
arytenoid, oblique	muscular process of the arytenoid cartilage	posterior surface of the contralateral arytenoid cartilage, near its apex	draws arytenoid cartilages together, adducting the vocal folds	inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the of vagus (X)	laryngeal br. of the superior thyroid a.	the oblique arytenoid m. lies posterior to the transverse arytenoid m.; the arytenoideus is often considered to be one muscle with oblique and transverse fibers (
arytenoid, transverse	posterior surface of the arytenoid cartilage	posterior surface of the contralateral arytenoid cartilage	draws arytenoid cartilages together, adducting the vocal folds	inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the vagus nerve (X)	laryngeal br. of the superior thyroid a.	the transverse arytenoid m.lies anterior to the oblique arytenoid m.; the arytenoideus is often considered to be one muscle with oblique and transverse parts
auricular	anterior: galea aponeurotica anterior to ear; superior: galea aponeurotica superior to ear; posterior: mastoid process	auricle anteriorly, superiorly and posteriorly	wiggle the ears	anterior & superior: temporal branches of facial nerve (VII); posterior: posterior auricular branch of facial nerve (VII)	superficial temporal a., posterior auricular a.	the auricular muscles are derived from the mesenchyme of the second pharyngeal arch, as are the muscles of facial expression
buccinator	pterygomandibular raphe, mandible, and the maxilla lateral to the molar teeth	angle of mouth and the lateral portion of the upper and lower lips	pulls the corner of mouth laterally; presses the cheek against the teeth	buccal branches of the facial nerve (VII)	facial a.	although the buccinator is important in mastication, it is innervated by the buccal branch of the facial nerve and NOT by the buccal nerve from V3 (a sensory nerve) (Latin, buccinator = trumpeter)
chondroglossus	medial side of the lesser horn and body of the hyoid bone	ascends to blend with the intrinsic tongue musculature	pulls the sides of the tongue down	hypoglossal nerve (XII)	lingual a.	chondroglossus is often considered to be part of the hyoglossus muscle
ciliary	meridional fibers: scleral spur; circular fibers: encircle the ciliary process	meridional fibers: ciliary process; circular fibers: encircle the ciliary process	relaxes the suspensory ligament of the lens	parasympathetic fibers in the oculomotor nerve (III), synapsing in the ciliary ganglion	ophthalmic a.	relaxation of the suspensory ligament allows the lens to thicken for accommodation (near vision)
constrictor, inferior pharyngeal	oblique line of the thyroid cartilage, lateral surface of cricoid cartilage	midline pharyngeal raphe	constricts pharyngeal cavity	vagus (X), via the pharyngeal plexus, with aid from the superior laryngeal and recurrent laryngeal nerves	ascending pharyngeal a., superior thyroid a., inferior thyroid a.	the most external of the three pharyngeal constructor mm.
constrictor, middle pharyngeal	lesser and greater horns of the hyoid bone and the inferior part of the stylohyoid ligament	midline pharyngeal raphe	constricts the pharyngeal cavity	vagus (X), via the pharyngeal plexus	ascending pharyngeal a.	of the three pharyngeal constrictors, this one is intermediate in both superior/inferior position and depth
constrictor, superior pharyngeal	medial pterygoid plate, pterygoid hamulus, pterygomandibular raphe, mylohyoid line of mandible	pharyngeal tubercle and midline pharyngeal raphe	constricts the pharyngeal cavity	vagus (X), via the pharyngeal plexus	ascending pharyngeal a.	the most internal of the three pharyngeal constructor mm.
corrugator	medial part of the supercillary arch	skin of the medial half of the eyebrow	pulls eyebrows together medially	temporal branch of the facial nerve (VII)	supratrochlear a.	this muscle causes the furrowed brow of the worried look (Latin, corrugator= to wrinkle)
cricoarytenoid, lateral	arch of the cricoid cartilage	muscular process of the arytenoid cartilage	draws the muscular process of the arytenoid cartilage anteriorly, which pivots the arytenoid cartilage and adducts the vocal folds	inferior laryngeal nerve, from the recurrent laryngeal nerve, a branch of the vagus nerve (X)	superior laryngeal a., cricothyroid branch of the superior thyroid a.	an antagonist of the posterior cricoarytenoid m.; the arteries that supply the larynx anastomose within the larynx to supply the mucous membranes and muscles
cricoarytenoid, posterior	posterior surface of the lamina of the cricoid cartilage	muscular process of the arytenoid cartilage	draws the muscular process posteriorly, which pivots the arytenoid cartilage and abducts the vocal folds	inferior laryngeal nerve, from the recurrent laryngeal nerve, a branch of the vagus nerve (X)	superior laryngeal a., cricothyroid branch of the superior thyroid a.	the posterior cricoarytenoid is the only ABductor of the vocal folds; the arteries that supply the larynx anastomose within the larynx to supply the mucous membranes and muscles
cricopharyngeus	lateral surface of the cricoid cartilage	midline pharyngeal raphe	constricts the pharyngeal cavity and the entrance to the esophagus	recurrent laryngeal nerve, a branch of the vagus nerve (X)	cricothyroid branch of the superior thyroid a., ascending pharyngeal a.	cricopharyngeus represents the lowest fibers of the inferior pharyngeal constrictor; it is continuous with the esophagus below and marks the beginning of it
cricothyroid	arch of the cricoid cartilage	inferior border of the thyroid cartilage	draws the thyroid cartilage forward, lengthening the vocal ligaments	external branch of superior laryngeal nerve, a branch of the vagus nerve (X)	cricothyroid branch of the superior thyroid a.	this is the only intrinsic muscle of the larynx that is not supplied by the recurrent laryngeal n.; ALL other laryngeal muscles are innervated by recurrent laryngeal nerve, via its inferior laryngeal branch
depressor anguli oris	oblique line of the mandible	angle of the mouth	pulls the corner of the mouth downward	marginal mandibular & buccal branches of the facial nerve (VII)	inferior labial branch of the facial a., mental a.	a "frown" muscle
depressor labii inferioris	anterior surface of the mandible	skin of the lower lip	depresses the lower lip	marginal mandibular branch of the facial nerve (VII)	inferior labial branch of the facial a., mental a.	this muscle is used to bare the lower incisor teeth
depressor septi	maxilla near the midline above the incisor teeth	nasal septum	depresses the nasal septum; involved in flaring the nostrils	buccal branch of facial nerve (VII)	superior labial branch of the facial a.	depressor septi is considered a part of the nasalis m.
digastric	anterior belly: digastric fossa of the mandible; posterior belly: mastoid notch of the temporal bone	body of the hyoid via a fibrous loop over an intermediate tendon	elevates the hyoid bone; depresses the mandible	anterior belly: mylohyoid nerve, from the mandibular division of the trigeminal nerve (V); posterior belly: facial nerve (VII)	anterior belly: submental a.; posterior belly: occipital a.	the digastric m. forms two sides of the submandibular triangle; it is formed from mesenchyme derived from the first two pharyngeal arches, hence its dual innervation
dilator pupillae	outer margin of iris	inner margin of iris	dilates the pupil	sympathetic fibers via short ciliary nerves, synapsing in superior cervical sympathetic ganglion	ophthalmic a.	none
epicranius	frontalis: galea aponeurotica; occipitalis: superior nuchal line	frontalis: skin of the eyebrows; occipitalis: galea aponeurotica	elevates the eyebrows and wrinkles the forehead	frontalis: temporal branches of the facial nerve (VII); occipitalis: posterior auricular branch of the facial nerve (VII)	frontalis: supraorbital and supratrochlear aa.; occipitalis: occipital a.	the frontalis and occipitalis muscles are two bellies of the epicranius muscle; also known as: occipitofrontalis m.
frontalis	galea aponeurotica	skin of the eyebrow	elevates the eyebrows and wrinkles the forehead	temporal branches of the facial nerve (VII)	supraorbital and supratrochlear aa.	frontalis is the anterior belly of the epicranius muscle
genioglossus	mental spine on the inner aspect of the mental symphysis	fans out to insert into the tongue from the tip to the base	protrudes the tongue (inferior fibers); depresses tongue (middle fibers)	hypoglossal nerve (XII)	lingual a.	an extrinsic muscle of the tongue; XII innervates all tongue muscles except palatoglossus [innervated by vagus (X), as are most of the palate and pharynx muscles]; genioglossus is used to test the function of cranial nerve XII
geniohyoid	mental spines of the mandible	body of the hyoid bone	elevates the hyoid bone; depresses the mandible	ventral primary ramus of spinal nerve C1 via fibers carried by the hypoglossal nerve	lingual a., submental a.	thyrohyoid and geniohyoid receive ansa cervicalis fibers that travel with the hypoglossal nerve distal to the superior limb of the ansa cervicalis
hyoglossus	upper border of the greater horn of the hyoid and body of the hyoid bone	spreads out into the intrinsic muscles of the tongue	depresses the sides of the tongue; retracts the tongue	hypoglossal nerve (XII)	lingual a.	an extrinsic muscle of the tongue
inferior oblique	floor of the orbit lateral to the lacrimal groove	sclera on the inferior surface of the eyeball	elevates and abducts the corneal part of the eye; rotates the superior pole of the iris laterally; when the eye is adducted, this muscle elevates the cornea	oculomotor nerve (III), inferior division	ophthalmic a.	clinicians examining the eye will ask the patient to look toward the bridge of the nose to test the function of this muscle
inferior pharyngeal constrictor	oblique line of the thyroid cartilage, lateral surface of cricoid cartilage	midline pharyngeal raphe	constricts pharyngeal cavity	vagus (X), via the pharyngeal plexus, with aid from the superior laryngeal and recurrent laryngeal nerves	ascending pharyngeal a., superior thyroid a., inferior thyroid a.	the most external of the three pharyngeal constructor mm.
inferior rectus	common tendinous ring at the apex of the orbit	sclera on the inferior surface of the eyeball	depresses and adducts the corneal part of the eyeball; rotates the superior pole of the iris laterally	oculomotor nerve (III), inferior division	ophthalmic a.	because this muscle approaches the eyeball from a medial direction, it has a rotational action on the iris
lateral cricoarytenoid	arch of the cricoid cartilage	muscular process of the arytenoid cartilage	draws the muscular process of the arytenoid cartilage anteriorly, which pivots the arytenoid cartilage and adducts the vocal folds	inferior laryngeal nerve, from the recurrent laryngeal nerve, a branch of the vagus nerve (X)	superior laryngeal a., cricothyroid branch of the superior thyroid a.	an antagonist of the posterior cricoarytenoid m.; the arteries that supply the larynx anastomose within the larynx to supply the mucous membranes and muscles
lateral pterygoid	superior head: greater wing of the sphenoid bone; inferior head: lateral surface of the lateral pterygoid plate	superior head: capsule and & articular disk of the temporomandibular joint; inferior head: neck of the mandible	protracts the mandible; opens the mouth; active in grinding actions of chewing	lateral pterygoid branch of the mandibular division of the trigeminal nerve (V)	pterygoid branch of the maxillary a.	the only one of the muscles of mastication that opens the mouth; the superior head of lateral pterygoid is sometimes called sphenomeniscus due to its insertion into the disc of the temporomandibular joint (Greek, pterygoid = wing-shaped)
lateral rectus	common tendinous ring at the apex of the orbit	sclera on the lateral surface of the eyeball	abducts the corneal part of the eyeball	abducens nerve (VI)	ophthalmic a.	loss of function of the abducens nerve will cause the eye to be abducted
levator anguli oris	canine fossa of the maxilla	angle (corner) of the mouth	elevates the angle of the mouth	buccal branch of the facial nerve (VII)	infraorbital a., superior labial branch of the facial a.	a "smile" muscle
levator labii superioris	inferior margin of the orbit	skin of the upper lip	elevates the upper lip	buccal branch of the facial nerve (VII)	infraorbital a., superior labial branch of the facial a.	levator labii superioris is used to bare the upper incisor teeth, as in a sneer (Latin, levator = to lift + labial = lips)
levator labii superioris alaque nasi	frontal process of the maxilla	ala of the nose and skin of the upper lip	elevates the upper lip and flares the nostril	buccal branch of the facial nerve (VII)	infraorbital a., superior labial branch of the facial a.	(Latin, levator = to lift + labial = lips)
levator palpebrae superioris	apex of the orbit above the optic canal	skin and fascia of upper eyelid and the superior tarsal plate	elevates the upper eyelid	oculomotor nerve (III) and sympathetics (to the superior tarsal portion)	ophthalmic a.	fibers inserting into the superior tarsal plate are called superior tarsal muscle and are smooth muscle; lesion of the sympathetic supply causes slight ptosis (drooping of the eyelid) (Latin, levator = to lift + palpebrae = eyelid)
levator scapulae	transverse processes of C1-4 vertebrae	medial border of the scapula from the superior angle to the spine	elevates scapula	dorsal scapular nerve (C5); the upper part of the muscle receives branches of C3 & C4 spinal nerves	dorsal scapular a.	named for its action (Latin, levator = to lift)
levator veli palatini	apex of the petrous part of the temporal bone and the medial surface of the auditory tube cartilage	muscles and fascia of the soft palate; palatine aponeurosis	elevates the soft palate	vagus nerve (X) via the pharyngeal plexus	ascending pharyngeal a.	a derivative of the fourth pharyngeal arch (Latin, levator = to lift)
linguae, longitudinalis	within tongue	within tongue near the apex	shapes the tongue for speech and mastication	hypoglossal nerve (XII)	lingual a.	an intrinsic muscle of the tongue; longitudinalis has superior and inferior subdivisions that span the length of the tongue
linguae, transversus	within tongue	within tongue	compresses the sides of the tongue; shapes the tongue for speech and mastication	hypoglossal nerve (XII)	lingual a.	an intrinsic muscle of the tongue whose fibers run transversely
linguae, verticalis	within tongue	within tongue	shapes the tongue for speech and mastication	hypoglossal nerve (XII)	lingual a.	an intrinsic muscle of the tongue whose fibers run superoinferiorly
longus capitis	anterior tubercles of vertebrae C3-6	basilar portion of the occipital bone	flex the head and neck	cervical plexus, ventral primary rami of spinal nerves C1-4	deep cervical a.	none
longus colli	anterior tubercles and anterior surfaces of the bodies of vertebrae C3-T3	anterior arch of atlas, anterior tubercles of C5-6, anterior surfaces of bodies of vertebrae C2-4	flex neck, rotate and laterally bend neck	cervical and brachial plexus, C2-7	deep cervical a.	none
masseter	zygomatic arch and zygomatic bone	lateral surface of the ramus and angle of the mandible	elevates the mandible	nerve to the masseter, from the mandibular division of the trigeminal nerve (V)	masseteric branch of the maxillary a.	(Greek, masseter = the chewer)
medial pterygoid	medial surface of the lateral pterygoid plate, pyramidal process of the palatine bone, tuberosity of the maxilla	medial surface of the ramus and angle of the mandible	elevates and protracts the mandible	medial pterygoid branch of the mandibular division of the trigeminal nerve (V)	pterygoid branch of the maxillary a.	this muscle mirrors the masseter m. in position and action with the ramus of the mandible between the two mm. (Greek, pterygoid = wing-shaped)
medial rectus	common tendinous ring at the apex of the orbit	sclera on the medial surface of the eyeball	adducts the corneal part of the eyeball	oculomotor nerve (III) (inferior division)	ophthalmic a.	this muscle directly opposes the action of the lateral rectus m.
mentalis	anterior surface of the mandible near the mental symphysis (midline)	skin of the chin	elevates the lower lip and skin of chin	marginal mandibular branch of the facial nerve (VII)	mental a., inferior labial branch of the facial a.
middle pharyngeal constrictor	lesser and greater horns of the hyoid bone and the inferior part of the stylohyoid ligament	midline pharyngeal raphe	constricts the pharyngeal cavity	vagus (X), via the pharyngeal plexus	ascending pharyngeal a.	of the three pharyngeal constrictors, this one is intermediate in both superior/inferior position and depth
middle scalene	posterior tubercles of the transverse processes of vertebrae C2-C7	upper surface of the first rib behind the subclavian artery	elevates the first rib; flexes and laterally bends the neck	brachial plexus, C3-C8	ascending cervical a.	a muscle of respiration (inspiratory); also called scalenus medius; penetrated by the dorsal scapular n. and long thoracic n. (Greek, scalene = uneven)
musculus uvulae	posterior nasal spine	mucosa of the uvula	shortens the uvula	vagus nerve (X) via pharyngeal plexus	lesser palatine a.	the soft palate and uvula resist the upward pressure of the tongue during swallowing
mylohyoid	mylohyoid line of mandible	midline raphe and body of the hyoid bone	elevates the hyoid bone and the tongue; depresses the mandible	mylohyoid nerve from the inferior alveolar nerve, a branch of the mandibular division of the trigeminal nerve (V)	mylohyoid branch of the inferior alveolar a.	the nerve to mylohyoid also innervates the anterior belly of digastric m.; both muscles are derivatives of the second pharygneal arch
nasalis	maxilla above the incisor teeth and the canine teeth	ala of the nose and midline aponeurosis	flattens the nose, flare the nostrils	buccal branch of the facial nerve (VII)	superior labial branch of the facial a.	nasalis has two subsidiary parts: nasalis pars alaris and pars transversa
nasalis pars alaris	maxilla above the canine teeth	ala of the nose	flares the nostrils	buccal branch of facial nerve (VII)	superior labial branch of the facial a.	a subdivision of the nasalis m. (Latin, pars = a part)
nasalis pars transversa	maxilla above the incisor teeth	midline aponeurosis	flattens the nose	buccal branch of facial nerve (VII)	superior labial branch of the facial a.	a subdivision of the nasalis m. (Latin, pars = a part)
oblique arytenoid	muscular process of the arytenoid cartilage	posterior surface of the contralateral arytenoid cartilage, near its apex	draws arytenoid cartilages together, adducting the vocal folds	inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the of vagus (X)	laryngeal br. of the superior thyroid a.	the oblique arytenoid m. lies posterior to the transverse arytenoid m.; the arytenoideus is often considered to be one muscle with oblique and transverse fibers
oblique, inferior	floor of the orbit lateral to the lacrimal groove	sclera on the inferior surface of the eyeball	elevates and abducts the corneal part of the eye; rotates the superior pole of the iris laterally; when the eye is adducted, this muscle elevates the cornea	oculomotor nerve (III), inferior division	ophthalmic a.	clinicians examining the eye will ask the patient to look toward the bridge of the nose to test the function of this muscle
oblique, superior	apex of the orbit above the optic canal	sclera on the posterior superior surface of the eyeball	depresses and abducts the eyeball; rotates the superior pole of the iris medially	trochlear nerve (IV)	ophthalmic a.	passes through a fibrocartilagenous pulley known as the trochlea; when the eye is adducted, this muscle moves the cornea inferiorly
occipitalis	superior nuchal line	galea aponeurotica	pulls the scalp posteriorly; elevates the eyebrows	posterior auricular branch of the facial nerve (VII)	occipital a.	occipitalis is the posterior belly of the epicranius muscle
occipitofrontalis	frontalis: galea aponeurotica; occipitalis: superior nuchal line	frontalis: skin of the eyebrows; occipitalis: galea aponeurotica	elevates the eyebrows and wrinkles the forehead	frontalis: temporal branches of the facial nerve (VII); occipitalis: posterior auricular branch of the facial nerve (VII)	frontalis: supraorbital and supratrochlear aa.; occipitalis: occipital a.	the frontalis and occipitalis muscles are two bellies of the occipitofrontalis muscle; also known as: epicranius m.
omohyoid	inferior belly: upper border of the scapula medial to the scapular notch; superior belly: intermediate tendon	inferior belly: intermediate tendon; superior belly: lower border of the hyoid bone lateral to the sternohyoid insertion	depresses/stabilizes the hyoid bone	ansa cervicalis	transverse cervical a.	the intermediate tendon of omohyoid is tethered to the clavicle by a fascial sling
orbicularis oculi	orbital part: medial orbital margin and the medial palpebral ligament; palpebral part: medial palpebral ligament	orbital part: skin of the lateral cheek; palpebral part: lateral palpebral raphe	closes the eyelids	temporal & zygomatic branches of the facial nerve (VII)	supraorbital a., supratrochlear a., infraorbital a., angular branch of the facial a.	activated involuntarily in the blink reflex; the palpebral part is active in normal blinking and the orbital part is used to forcefully close the eye
orbicularis oris	skin and fascia of lips and the area surrounding the lips	skin and fascia of the lips	purses the lips	buccal branch of the facial nerve (VII)	superior and inferior labial branches of the facial a., mental a., infraorbital a.	the "kissing" muscle
palatoglossus	palatine aponeurosis	side of the tongue, entering it from above	elevates and retracts the tongue	vagus nerve (X) via the pharyngeal plexus	tonsilar branch of the facial a., ascending pharyngeal a.	although palatoglossus sounds like a tongue muscle (and would therefore be innervated by XII), it is a palatal muscle innervated by X
palatopharyngeus	posterior margin of the bony palate and the palatine aponeurosis	posterior wall of the pharynx and the posterior margin of the thyroid cartilage	elevates the larynx	vagus nerve (X) via pharyngeal plexus	ascending pharyngeal a.	palatopharyngeus is part of the inner longitudinal muscle layer of the pharynx
platysma	fascia overlying the pectoralis major and deltoid muscles	inferior border of the mandible and skin of lower face	draws the corners of the mouth down; it aids in depression of the mandible	cervical branch of the facial nerve (VII)	facial a.	platysma is derived from the mesenchyme of the second pharyngeal arch (Greek, platysma = a flat plate)
posterior cricoarytenoid	posterior surface of the lamina of the cricoid cartilage	muscular process of the arytenoid cartilage	draws the muscular process posteriorly, which pivots the arytenoid cartilage and abducts the vocal folds	inferior laryngeal nerve, from the recurrent laryngeal nerve, a branch of the vagus nerve (X)	superior laryngeal a., cricothyroid branch of the superior thyroid a.	the posterior cricoarytenoid is the only ABductor of the vocal folds; the arteries that supply the larynx anastomose within the larynx to supply the mucous membranes and muscles
posterior scalene	posterior tubercles of the transverse processes of vertebrae C5-C7	lateral surface of the second rib	elevates the second rib; flexes and laterally bends the neck	brachial plexus, C7-C8	ascending cervical a.	a muscle of respiration (inspiratory); it is the longest of the scalene muscles (Greek, scalene = uneven)
procerus	nasal bone	skin between the eyebrows	depresses the medial corners of the eyebrows	temporal branch of the facial nerve (VII)	supratrochlear a.	(Latin, procerus = long and streched out)
pterygoid, lateral	superior head: greater wing of the sphenoid bone; inferior head: lateral surface of the lateral pterygoid plate	superior head: capsule and & articular disk of the temporomandibular joint; inferior head: neck of the mandible	protracts the mandible; opens the mouth; active in grinding actions of chewing	lateral pterygoid branch of the mandibular division of the trigeminal nerve (V)	pterygoid branch of the maxillary a.	the only one of the muscles of mastication that opens the mouth; the superior head of lateral pterygoid is sometimes called sphenomeniscus due to its insertion into the disc of the temporomandibular joint (Greek, pterygoid = wing-shaped)
pterygoid, medial	medial surface of the lateral pterygoid plate, pyramidal process of the palatine bone, tuberosity of the maxilla	medial surface of the ramus and angle of the mandible	elevates and protracts the mandible	medial pterygoid branch of the mandibular division of the trigeminal nerve (V)	pterygoid branch of the maxillary a.	this muscle mirrors the masseter m. in position and action with the ramus of the mandible between the two mm. (Greek, pterygoid = wing-shaped)
pupillae, dilator	outer margin of iris	inner margin of iris	dilates the pupil	sympathetic fibers via short ciliary nerves, synapsing in superior cervical sympathetic ganglion	ophthalmic a.	none
pupillae, sphincter	encircles iris	encircles iris	constricts the pupil	parasympathetic fibers of oculomotor nerve (III), synapsing in ciliary ganglion	ophthalmic a.	none
rectus capitis anterior	lateral mass of atlas	basilar portion of occipital bone	flexes the head	ventral primary ramus of spinal nerve C1	deep cervical a.	none
rectus capitis lateralis	transverse process of atlas	occipital bone anterolateral to foramen magnum	laterally bends the head	ventral primary ramus of spinal nerve C1	deep cervical a.	none
rectus, inferior	common tendinous ring at the apex of the orbit	sclera on the inferior surface of the eyeball	depresses and adducts the corneal part of the eyeball; rotates the superior pole of the iris laterally	oculomotor nerve (III), inferior division	ophthalmic a.	because this muscle approaches the eyeball from a medial direction, it has a rotational action on the iris
rectus, lateral	common tendinous ring at the apex of the orbit	sclera on the lateral surface of the eyeball	abducts the corneal part of the eyeball	abducens nerve (VI)	ophthalmic a.	loss of function of the abducens nerve will cause the eye to be abducted
rectus, medial	common tendinous ring at the apex of the orbit	sclera on the medial surface of the eyeball	adducts the corneal part of the eyeball	oculomotor nerve (III) (inferior division)	ophthalmic a.	this muscle directly opposes the action of the lateral rectus m.
rectus, superior	common tendinous ring at the apex of the orbit	sclera on the superior surface of the eyeball	elevates and adducts the eyeball; rotates the superior pole of the iris medially	oculomotor nerve (III), superior division	ophthalmic a.	because this muscle approaches the eye from a medial position, it causes the iris to rotate medially
risorius	fascia of the lateral cheek	skin of the angle (corner) of the mouth	draws the corner of the mouth laterally	buccal branches of the facial nerve (VII)	transverse facial a., facial a.	risorius is active in expressions of mirth (Latin, risorius = to laugh)
salpingopharyngeus	inferior surface of the anteromedial end of the auditory tube cartilage	pharyngeal wall and superior border of the thyroid cartilage along with the palatopharyngeus m.	elevates the larynx	vagus nerve (X) via the pharyngeal plexus	ascending pharyngeal a.	like other muscles of the pharyngeal wall, salpingopharyngeus is derived from the fourth pharyngeal arch
scalene, anterior	anterior tubercles of the transverse processes of vertebrae C3-C6	scalene tubercle of the first rib	elevates the first rib; flexes and laterally bends the neck	brachial plexus, C5-C7	ascending cervical a., a branch of the thyrocervical trunk	a muscle of inspiration; an important landmark of the neck; it is located between the subclavian vein and the subclavian artery; the roots of the brachial plexus pass posterior to it; the phrenic nerve crosses its anterior surface (Greek, scalene = uneven)
scalene, middle	posterior tubercles of the transverse processes of vertebrae C2-C7	upper surface of the first rib behind the subclavian artery	elevates the first rib; flexes and laterally bends the neck	brachial plexus, C3-C8	ascending cervical a.	a muscle of respiration (inspiratory); also called scalenus medius; penetrated by the dorsal scapular n. and long thoracic n. (Greek, scalene = uneven)
scalene, posterior	posterior tubercles of the transverse processes of vertebrae C5-C7	lateral surface of the second rib	elevates the second rib; flexes and laterally bends the neck	brachial plexus, C7-C8	ascending cervical a.	a muscle of respiration (inspiratory); it is the longest of the scalene muscles (Greek, scalene = uneven)
sphenomeniscus	greater wing of the sphenoid	capsule and articular disk of the temporomandibular joint	pulls the articular disk forward in opening of the mouth	lateral pterygoid branch of mandibular division of trigeminal nerve (V)	pterygoid branch of the maxillary a.	sphenomeniscus is another name for the superior belly of the lateral pterygoid m.
sphincter pupillae	encircles iris	encircles iris	constricts the pupil	parasympathetic fibers of oculomotor nerve (III), synapsing in ciliary ganglion	ophthalmic a.	none
splenius	ligamentum nuchae and spines C7-T6	capitis: mastoid process & superior nuchal line laterally; cervicis: posterior tubercles of C1-3	extends and laterally bends neck and head; rotates head to same side	dorsal primary rami of spinal nerves C2-6	supplied segmentally by: deep cervical a., posterior intercostal aa.	it gets its name from its broad, flat shape (Greek, splenius = a bandage)
stapedius	walls of the pyramidal eminence	neck of the stapes	dampens vibration of the stapes	facial nerve (VII)	anterior tympanic a.	entirely enclosed in bone, except for its tendon; a derivative of the second pharyngeal arch
sternocleidomastoid	sternal head: anterior surface of the manubrium; clavicular head: medial 1/3rd of the clavicle	mastoid process and lateral 1/2 of the superior nuchal line	draws the mastoid process down toward the same side which causes the chin to turn up toward the opposite side; acting together, the muscles of the two sides flex the neck	spinal accessory nerve (XI), with sensory supply from C2 & C3 (for proprioception)	sternocleidomastoid branch of the occipital a.	carotid sheath structures lie deep to it
sternohyoid	posterior surfaces of both the manubrium and sternal end of the clavicle	lower border of the hyoid bone, medial to the omohyoid m. insertion	depresses/stabilizes the hyoid bone	ansa cervicalis	superior thyroid a.	sternohyoid overlies the sternothyroid and thyrohyoid mm.
sternothyroid	posterior surface of the manubrium below the origin of the sternohyoid m.	oblique line of the thyroid cartilage	depresses/stabilizes the hyoid bone	ansa cervicalis	superior thyroid a.	sternothyroid lies deep to the sternohyoid m.
styloglossus	anterior side of the styloid process	posterolateral side of the tongue	retracts and elevates the tongue	hypoglossal nerve (XII)	ascending pharyngeal a., ascending palatine branch of the facial a.	an extrinsic muscle of the tongue
stylohyoid	posterior side of the styloid process	splits around the intermediate tendon of the digastric m. to insert on the body of the hyoid bone	elevates and retracts the hyoid bone	facial nerve (VII)	ascending pharyngeal a.	facial nerve innervates both the stylohyoid m. and the posterior belly of the digastric m. shortly after exiting from the stylomastoid foramen
stylopharyngeus	medial side of the styloid process	superior border of the thyroid cartilage and also into the pharyngeal wall	elevates the larynx	glossopharyngeal nerve (IX)	ascending pharyngeal a.	stylopharyngeus, the only muscle innervated by IX, is the only muscle of the pharyngeal wall NOT innervated by the vagus (X) nerve; it is a derivative of the third pharyngeal arch
superior oblique	apex of the orbit above the optic canal	sclera on the posterior superior surface of the eyeball	depresses and abducts the eyeball; rotates the superior pole of the iris medially	trochlear nerve (IV)	ophthalmic a.	passes through a fibrocartilagenous pulley known as the trochlea; when the eye is adducted, this muscle moves the cornea inferiorly
superior pharyngeal constrictor	medial pterygoid plate, pterygoid hamulus, pterygomandibular raphe, mylohyoid line of mandible	pharyngeal tubercle and midline pharyngeal raphe	constricts the pharyngeal cavity	vagus (X), via the pharyngeal plexus	ascending pharyngeal a.	the most internal of the three pharyngeal constructor mm.
superior rectus	common tendinous ring at the apex of the orbit	sclera on the superior surface of the eyeball	elevates and adducts the eyeball; rotates the superior pole of the iris medially	oculomotor nerve (III), superior division	ophthalmic a.	because this muscle approaches the eye from a medial position, it causes the iris to rotate medially
temporalis	temporal fossa and the temporal fascia	coronoid process of the mandible and the anterior surface of the ramus of the mandible	elevates the mandible; retracts the mandible (posterior fibers)	anterior and posterior deep temporal nerves from the mandibular division of the trigeminal nerve (V)	anterior and posterior deep temporal aa.	a powerful chewing muscle; a derivative of the first pharyngeal arch
tensor tympani	cartilagenous auditory tube and the greater wing of the sphenoid bone which lies adjacent to it	manubrium of the malleus	dampens vibrations of the tympanic membrane	medial pterygoid branch of the mandibular division of the trigeminal nerve (V)	superior tympanic branch of the middle meningeal a.	V3 innervates both tensor muscles of the head (tympani and veli palatini) which are derivatives of the first pharyngeal arch