Medial rectus muscle

Medial rectus

Rectus muscles: 2 = superior, 3 = inferior, 4 = medial, 5 = lateral Oblique muscles: 6 = superior, 8 = inferior Other muscle: 9 = levator palpebrae superioris Other structures: 1 = Annulus of Zinn, 7 = Trochlea, 10 = Superior tarsus, 11 = Sclera, 12 = Optic nerve

Figure showing the mode of innervation of the Recti medialis and lateralis of the eye.
Latin	musculus rectus medialis bulbi
Gray's	subject #227 1022
Origin	annulus of Zinn at the orbital apex
Insertion	5.5 mm medial to the limbus
Artery:
Nerve:	inferior division of the oculomotor nerve
Action:	adducts the eyeball (makes it move inwards)
Dorlands /Elsevier	m_22/12550510

The medial rectus muscle is a muscle in the orbit.

As with most of the muscles of the orbit, it is innervated by the inferior division of the oculomotor nerve (Cranial Nerve III).

This muscle shares an origin with several other extrinsic eye muscles, the anulus tendineus, or common tendon.

It is the largest of the extraocular muscles and its only action is adduction of the eyeball.

[edit] Additional images

Eye movement of lateral rectus muscle, superior view	Eye movement of medial rectus muscle, superior view	Eye movement of inferior rectus muscle, superior view	Eye movement of superior rectus muscle, superior view
Eye movement of superior oblique muscle, superior view	Eye movement of inferior oblique muscle, superior view	Anterior view

credit: Patrick J. Lynch

Horizontal section of the eyeball.

Dissection showing origins of right ocular muscles, and nerves entering by the superior orbital fissure.

v • d • e

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)