| 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 |
| 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) |
| 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 |
| 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 |
| 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 adducted |
| 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 |
| 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. | none |
| 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) |
| 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 |
| 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 |
| 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. | a powerful chewing muscle |
| 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. |
| 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 skin of chin | marginal mandibular branch of the facial nerve (VII) | mental a., inferior labial branch of the facial a. | mentalis has no direct action on the oral aperture |
| 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. |
| 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. |
| 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. |
| 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 |
| 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 |
| procerus | nasal bone | skin between the eyebrows | depresses the medial corners of the eyebrows | temporal branch of the facial nerve (VII) | supratrochlear a. | none |
| 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 |
| 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. |
| 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 adducted |
| 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 |
| 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 |
| 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. |
| 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 |
| 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. | splenius means bandage; it gets its name from its broad, flat shape |
| 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 |
| tensor veli palatini | scaphoid fossa, lateral wall of the auditory tube cartilage | palatine aponeurosis | opens the auditory tube; tenses the soft palate | mandibular division of the trigeminal nerve (V) | ascending pharyngeal a. | remember: V3 innervates both tensor muscles (tympani and veli palatini); ALL other palatal muscles are innervated by vagus |
| thyroarytenoid | inner surface of the thyroid cartilage anteriorly | lateral border of the arytenoid cartilage | draws the arytenoid cartilage forward, relaxing and adducting the vocal folds | inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the vagus nerve (X) | laryngeal branch of the superior thyroid a. | its subsidiary parts are the thyroepiglottic m. and the vocalis m.; the medial most fibers of thyroarytenoid that insert along the vocal ligament are called the vocalis muscle |
| thyroepiglottic | inner surface of the thyroid cartilage near the laryngeal prominence | lateral surface of the epiglottic cartilage | draws the epiglottic cartilage downward | inferior laryngeal nerve, from recurrent laryngeal nerve, a branch of the vagus nerve (X) | laryngeal branch of the superior thyroid a. | represents the superior fibers of thyroarytenoid muscle which fan out to the quadrangular membrane and epiglottis |
| thyrohyoid | oblique line of the thyroid cartilage | lower border of the hyoid bone | elevates the larynx; depresses/stabilizes the hyoid bone | ansa cervicalis (via fibers running with the hypoglossal nerve that leave XII distal to the superior limb of ansa) | superior thyroid a. | thyrohyoid lies deep to the sternohyoid |
| trachealis | posterior edge of the tracheal cartilage | posterior edge of the tracheal cartilage of other side (joins tracheal rings posteriorly) | constricts the bronchi and trachea | preganglionic parasympathetic fibers from the vagus (X) nerve | inferior thyroid a., bronchial aa. | smooth muscle, found in the submucosal layer |
| transverse arytenoid | 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 |
| transverse arytenoid | 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 |
| vocalis | surface of the thyroid cartilage, vocal process of the arytenoid cartilage | vocal ligament | relaxes segments of the vocal ligament, thereby adjusting pitch | inferior laryngeal nerve, from the recurrent laryngeal nerve, a branch of the vagus nerve (X) | laryngeal br. of the superior thyroid a. | represents the innermost fibers of the thyroarytenoid muscle; the cricothyroid m. grossly tenses the vocal ligaments, while the vocalis muscle provides the mechanism for fine tuning the vibrations of the vocal folds |
| zygomaticus major | upper lateral surface of the zygomatic bone | skin of the angle of the mouth | elevates and draws the corner of the mouth laterally | zygomatic and buccal branches of the facial nerve (VII) | transverse facial a., facial a. | a "smile" muscle |
| zygomaticus minor | lower surface of the zygomatic bone | lateral part of the upper lip | elevates the upper lip | buccal branch of the facial nerve (VII) | transverse facial a., facial a. | a "smile" muscle |