Muscles of orbit

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Muscles of the orbit from Gray's Anatomy

There are seven muscles of the orbit; one controls the movement of the upper eyelid, and six others control the movement of the eye.

Muscle	Innervation	Primary function	Secondary function	Tertiary function
Levator palpebrae superioris	Oculomotor nerve	Elevation of the superior (upper) eyelid	.	.
Superior rectus	Oculomotor nerve	Elevation	Intorsion	Adduction
Inferior rectus	Oculomotor nerve	Depression	Extorsion	Adduction
Lateral rectus	Abducens nerve	Abduction	.	.
Medial rectus	Oculomotor nerve	Adduction	.	.
Superior oblique	Trochlear nerve	Intorsion	Depression	Abduction
Inferior oblique	Oculomotor nerve	Extorsion	Elevation	Abduction

A good mnemonic to remember which muscles are innervated by what nerve is to paraphrase it as a molecular equation: LR₆SO₄R₃.
Lateral Rectus - Cranial Nerve VI,
Superior Oblique - Cranial Nerve IV,
the Rest of the muscles - Cranial Nerve III.

Another way to remember which nerves innervate which muscles is to understand the meaning behind all of the Latin words. The fourth cranial nerve, the trochlear, is so named because the muscle it innervates, the superior oblique, runs through a little fascial pulley that changes its direction of pull. This pulley exists in the superiomedial corner of each orbit, and "trochl-" is Latin for "pulley." The sixth cranial nerve, the abducens, is so named because it controls the lateral rectus, which abducts the eye (rotates it laterally) upon contraction. All of the other muscles are controlled by the third cranial nerve, the oculomotor, which is so named because it is in charge of the movement (motor) of the eye (oculo-).

v • d • e Muscles of orbit
Levator palpebrae superioris muscle - Superior rectus muscle - Inferior rectus muscle - Lateral rectus muscle - Medial rectus muscle - Superior oblique muscle - Inferior oblique muscle

v • d • e

List of muscles of head and neck: the head

Extraocular (CN III, IV, VI)

oblique (inferior, superior) - rectus (superior, inferior, medial, lateral) - levator palpebrae superioris (superior tarsal)

Mastication (CN V3)

masseter - temporalis - pterygoid (lateral, medial)

Facial (CN VII)

Ear	auriculares (anterior, superior, posterior) - temporoparietalis
Scalp/eyelid	occipitofrontalis (occipitalis, frontalis) - orbicularis oculi (depressor supercilii) - corrugator supercilii
Nose	procerus - nasalis (dilatator naris) - depressor septi nasi - levator labii superioris alaeque nasi
Mouth	levator anguli oris - levator labii superioris - zygomaticus (major, minor) orbicularis oris - risorius - buccinator depressor anguli oris - depressor labii inferioris - mentalis

Mouth/throat (CN IX, X, XI)
(except TVP=V3)

Soft palate	veli palatini (tensor, levator) - musculus uvulae - palatopharyngeus (to pharnyx) - palatoglossus (to tongue)
Pharynx	pharyngeal constrictor (superior, middle, inferior) - longitudinal (stylopharyngeus, salpingopharyngeus)
Larynx	cricothyroid - cricoarytenoid (posterior, lateral) - arytenoid (oblique arytenoid/aryepiglottic, transverse arytenoid) - thyroarytenoid (vocal, thyroepiglottic)