Medial rectus muscle

The medial rectus muscle (rectus medialis) is a muscle of the eye that contracts to turn the eye inward, toward the center of the body.

Origin
The medial rectus originates from the back of the eye socket, at the medial side of the annulus of Zinn.

Insertion
The medial rectus inserts at the side of the eye, on the medial sclera just passed the equator of the eye.

Innervation
The medial rectus is innervated by the inferior division of the oculomotor nerve (CN III).