Extraocular Muscles

Superior Rectus
Inferior Rectus
Medial Rectus
Lateral Rectus
Inferior Oblique
Superior Oblique

The Superior Rectus arises from the superior tendinous ring at the apex of the orbit and inserts on the superior sclera anterior to the equator of the eyeball. It elevates the eye. The oculomotor nerve (CNIII) innervates the superior rectus muscle.

The Inferior Rectus arises from an inferior tendinous ring at the apex of the orbit and attaches to the inferior sclera anterior to the equator of the eyeball. It depresses the eye. The oculomotor nerve (CNIII) innervates the inferior rectus muscle.

The Medial Rectus arises from the common tendinous ring. It inserts on the medial sclera anterior to the equator of the globe. It adducts the eye. The oculomotor nerve (CNIII) innervates the medial rectus muscle.

The Lateral Rectus abducts the eye. The abducens nerve (CNVI) innervates the lateral rectus muscle.

The Inferior Oblique arises from the floor of the orbital surface of the maxilla and attaches to the sclera behind the equator of the eyeball. It laterally rotates the eye in abduction. The oculomotor nerve (CNIII) innervates the inferior oblique muscle.

The Superior Oblique arises from the body of the sphenoid at the apex of the orbit above the optic canal. Its tendon passes through a fibrocartilaginous pulley (trochlea) and attaches to the posterior/superior quadrant of the sclera behind the equator of the eyeball. It depresses the eye in adduction, and medially rotates the eye in abduction (seen as a medial rotation of the superior pole of the iris). The trochlear nerve (CNIV) innervates the superior oblique muscle.