Lateral Rectus

Description

Positioned on the lateral aspect of the adult male globe, the lateral rectus (musculus rectus lateralis) courses anteriorly from the annulus tendineus communis at the orbital apex toward its broad, flattened tendon inserting on the sclera posterior to the corneoscleral limbus. The belly lies lateral to the optic nerve and posterior pole of the eyeball, paralleling the globe’s equator before fanning into the terminal tendon. Adjacent recti are partially visible superiorly and inferiorly, framing the lateral rectus along the temporal side of the sclera. A blue-toned oblique muscle may be present deeper and posteriorly, crossing toward the superior or inferior aspect of the globe. Lateral rectus anatomy matters because it is the primary abductor of the eye and the extraocular muscle most directly linked to cranial nerve VI function; denervation produces an esotropia with failure of abduction and horizontal diplopia that worsens on gaze toward the affected side. Orbital apex lesions, raised intracranial pressure, and cavernous sinus pathology can all present with abducens palsy, so the muscle’s relationship to the optic nerve and the crowded posterior orbit is more than academic. The flattened insertion is also a surgical landmark for strabismus procedures (recession or resection), where tendon width and its position relative to the limbus guide suture placement. Small distances matter. Use this illustration in neuroanatomy teaching on extraocular muscle innervation, in ophthalmology and orthoptics modules covering comitant strabismus, and in surgical atlases depicting lateral rectus exposure and tendon handling through a limbal or fornix conjunctival incision. It also supports patient education materials explaining sixth nerve palsy and the mechanical basis of esotropia. Anatomical accuracy verified by SciePro's Medical Advisory Board.