Inferior Rectus Muscle

Description

Centered on the adult male globe, the inferior rectus runs along the inferior surface of the sclera from the common tendinous ring at the orbital apex to its insertion on the anterior inferior sclera, just posterior to the limbus. Superior to it, the superior rectus caps the globe, while the medial rectus sits medial (nasal) and the lateral rectus lateral (temporal), forming the familiar rectus cone around the optic nerve. The superior oblique courses superomedially toward the trochlea before turning posterolaterally across the globe, and the inferior oblique arises anteromedially on the orbital floor and passes posterolaterally beneath the inferior rectus. Orbital fat interposes between the inferior rectus and the orbital floor. This configuration matters because inferior rectus tethering and restriction drive the classic hypotropia and limited elevation of thyroid eye disease, where an enlarged, fibrotic inferior rectus is the usual culprit. It also frames common surgical decision points: inferior rectus recession for vertical strabismus, the close relationship to the inferior oblique during dissection, and the risk of anterior segment ischemia when multiple rectus muscles are operated in the same eye. A tight inferior rectus is a common postoperative problem after orbital floor fracture repair as well, when scarring or implant position impinges the muscle. Use this artwork in gross anatomy and ophthalmology teaching to explain extraocular muscle actions, rectus insertions relative to the limbus, and the anteromedial origin of the inferior oblique on the orbital floor. It also fits strabismus texts and surgical atlases illustrating approaches to inferior rectus recession, inferior oblique weakening procedures, and differential diagnosis of restrictive diplopia. Anatomical accuracy verified by SciePro's Medical Advisory Board.