Inferior rectus muscle

Inferior 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

Sagittal section of right orbital cavity.
Latin	musculus rectus inferior bulbi
Gray's	subject #227 1022
Origin	annulus of Zinn at the orbital apex
Insertion	6.5 mm inferior to the limbus
Artery:
Nerve:	inferior branch of oculomotor nerve
Action:	depression and adduction
Dorlands /Elsevier	m_22/12550484

The inferior rectus muscle is a muscle in the orbit.

[edit] Actions

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

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

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

The right eye in sagittal section, showing the fascia bulbi (semidiagrammatic).

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)