Inferior rectus at a glance
- What it is
- An extraocular muscle on the floor of the orbit.
- Location
- Origin: common tendinous ring. Insertion: inferior part of the sclera.
- Function
- Depresses the eyeball, with some adduction and extorsion.
- Body system
- Muscular · paired (left and right)
- FMA ID
- FMA49047 (Foundational Model of Anatomy)
Key facts
- Innervation: oculomotor nerve (CN III)
- It is tested by asking the patient to look down with the eye turned out (depression in abduction).
- Blood supply: muscular branches of the ophthalmic artery and the infraorbital artery
Clinical relevance
It can be trapped in an orbital floor (blowout) fracture, limiting upward gaze and causing double vision.
Structures next to the inferior rectus
The nearest named structures in the 3D model, measured from the centre of each part:
- Inferior branch of oculomotor nerve · nervous
- Lateral rectus · muscular
- Long ciliary nerve · nervous
- Medial rectus · muscular
- Ciliary ganglion · nervous
- Optic part of retina · eye & ear
- Vitreous body · eye & ear
- Sclera · eye & ear
- Choroid · eye & ear
- Superior rectus · muscular
References
- Foundational Model of Anatomy: Inferior rectus (FMA49047). EMBL-EBI Ontology Lookup Service.
- OpenStax. Anatomy and Physiology 2e, §11.2 Naming Skeletal Muscles. Rice University, 2022.
- Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.
Related anatomy
Explore the whole body in the interactive 3D human anatomy model, or browse the A–Z list of human structures.