Medial rectus muscle
The medial rectus muscle is a muscle in the orbit.
| Medial rectus | |
|---|---|
 Rectus muscles: 2 = superior, 3 = inferior, 4 = medial, 5 = lateral Oblique muscles: 6 = superior, 8 = inferior Other muscle: 9 = levator palpebrae superioris Other structures: 1 = Annulus of Zinn, 7 = Trochlea, 10 = Superior tarsus, 11 = Sclera, 12 = Optic nerve | |
 Figure showing the mode of innervation of the Recti medialis and lateralis of the eye. | |
| Details | |
| Origin | annulus of Zinn at the orbital apex |
| Insertion | 5.5 mm medial to the limbus |
| Nerve | inferior division of the oculomotor nerve |
| Actions | adducts the eyeball (makes it move inwards) |
| Identifiers | |
| Latin | musculus rectus medialis bulbi |
| TA98 | A15.2.07.012 |
| TA2 | 2044 |
| FMA | 49037 |
| Anatomical terms of muscle | |
As with most of the muscles of the orbit, it is innervated by the inferior division of the oculomotor nerve (Cranial Nerve III).
This muscle shares an origin with several other extrinsic eye muscles, the anulus tendineus, or common tendon.
It is shorter but stronger than the other orbital recti muscles.[1]
Additional imagesEdit
Eye movement of medial rectus muscle, superior view.
Horizontal section of the eyeball.
Dissection showing origins of right ocular muscles, and nerves entering by the superior orbital fissure.
Medial rectus muscle
Medial rectus muscle
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
Extrinsic eye muscle. Nerves of orbita. Deep dissection.
ReferencesEdit
- ^ Standring, Susan (2016). Gray's anatomy: the anatomical basis of clinical practice (41 ed.). Elsevier Limited. pp. 666–685. ISBN 978-0-7020-5230-9.
External linksEdit
- Anatomy figure: 29:01-06 at Human Anatomy Online, SUNY Downstate Medical Center
- lesson3 at The Anatomy Lesson by Wesley Norman (Georgetown University) (orbit4)
- Diagram at howstuffworks.com
 | This muscle article is a stub. You can help Wikipedia by expanding it. |
 | This article about the eye is a stub. You can help Wikipedia by expanding it. |