View source for Medial rectus muscle

{{Muscle infobox |
  Name         = Medial rectus |
  Latin        = musculus rectus medialis bulbi |
  GraySubject  = 227 |
  GrayPage     = 1022 |
  Image        = Eyemuscles.png |
  Caption      = ''Rectus muscles:'' <BR>2 = [[Superior rectus muscle|superior]], 3 = [[Inferior rectus muscle|inferior]], 4 = [[Medial rectus muscle|medial]], 5 = [[Lateral rectus muscle|lateral]]<br>''Oblique muscles:'' 6 = [[Superior oblique muscle|superior]], 8 = [[Inferior oblique muscle|inferior]]<br>''Other muscle:'' 9 = [[levator palpebrae superioris muscle|levator palpebrae superioris]]<br>''Other structures:'' 1 = [[Annulus of Zinn]], 7 = [[Trochlea of superior oblique|Trochlea]], 10 = [[Tarsi|Superior tarsus]], 11 = [[Sclera]], 12 = [[Optic nerve]] |
  Image2       = Gray785.png |
  Caption2     = Figure showing the mode of innervation of the Recti medialis and lateralis of the eye. |
  Origin       = [[annulus of Zinn]] at the orbital apex |
  Insertion    = 5.5 mm medial to the [[limbus]] |
  Blood        = |
  Nerve        = inferior division of the [[oculomotor nerve]] |
  Action       = [[adducts]] the eyeball (makes it move inwards) |
  DorlandsPre  = m_22 |
  DorlandsSuf  = 12550510  |
}}


The '''medial rectus muscle''' is a [[muscle]] in the [[orbit (anatomy)|orbit]].

As with most of the muscles of the orbit, it is [[innervation|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 the largest of the extraocular muscles and its only action is adduction of the eyeball.

==Additional images==
<gallery>
 Image:Gray869.png|Horizontal section of the eyeball.
 Image:Gray890.png|Dissection showing origins of right ocular muscles, and nerves entering by the superior orbital fissure.
 Image:ThreeNeuronArc.png |[[Vestibulo-ocular reflex]]
</gallery>

==External links==
* {{MuscleLoyola|mr}}
* {{GPnotebook|-1476001712}}
* {{SUNYAnatomyFigs|29|01|06}}
* {{eMedicineDictionary|medial+rectus+muscle}}
* {{NormanAnatomy|lesson3}} ({{NormanAnatomyFig|orbit4}})
* [http://static.howstuffworks.com/gif/vision3.gif Diagram at howstuffworks.com]

{{Muscles of head}}

[[Category:Muscles of the head and neck]]
[[Category:Eye]]

[[hu:Musculus rectus medialis]]
[[nl:Musculus rectus medialis]]
[[ja:内側直筋]]

{{WH}}
{{WikiDoc Sources}}