Muscle · Head

Lateral rectus

Musculus rectus lateralis

The straight muscle along the outer wall of the eye socket that turns the eye away from the nose. Like the medial rectus it has a single pure action, and like it, it starts from the shared fibrous ring at the back of the orbit — but uniquely it arises by two heads that straddle the gap where the nerves enter the socket. It is the only muscle supplied by the abducens nerve, which has the longest intracranial course of any cranial nerve, and that pairing is why an eye that will not turn outward is such a specific finding.