View source for Inferior oblique muscle

{{Muscle infobox |
  Name         = Inferior oblique |
  Latin        = musculus obliquus inferior bulbi  |
  GraySubject  = 227 |
  GrayPage     = 1023 |
  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       = Gray888.png | 
  Caption2     = [[Sagittal]] section of right orbital cavity. |
  Origin       = orbital surface of the [[maxilla]], lateral to the [[lacrimal groove]] |
  Insertion    = laterally onto the [[eyeball]], deep to the [[lateral rectus]], by a short flat tendon |
  Blood        = |
  Nerve        = [[oculomotor nerve]] |
  Action       = [[extorsion]], [[Elevation (kinesiology)|elevation]], [[Abduction (kinesiology)|abduction]]  |
  DorlandsPre  = m_22 |
  DorlandsSuf  = 12549875  |
}}
{{CMG}}



The '''Obliquus oculi inferior''' (inferior oblique) is a thin, narrow muscle, placed near the anterior margin of the floor of the [[orbit (anatomy)|orbit]]. 

==Action==
Its [[Muscles_of_orbit|actions]] are lateral rotation, elevation and abduction of the eye.

Primary action is [[extorsion]]; secondary action is [[Elevation (kinesiology)|elevation]]; tertiary action is [[Abduction (kinesiology)|abduction]] (i.e. it extorts the eye and moves it upward and outward).   The field of maximal inferior oblique elevation is in the adducted position.

==Path==
It arises from the orbital surface of the [[maxilla]], lateral to the [[lacrimal groove]]. 

Passing lateralward, backward, and upward,  between the [[inferior rectus]] and the floor of the orbit, the inferior oblique inserts onto the [[sclera]]l surface between the [[inferior rectus]] and [[lateral rectus]].

It is the only muscle of eye movement whose origin is not on the common tendonous ring ([[annulus of Zinn]]).  

==Innervation==
The inferior oblique is innervated by the inferior division of the [[oculomotor nerve]] (cranial nerve III).  

==Clinical significance==
While commonly affected by palsies of the inferior division of the oculomotor nerve, isolated palsies of the inferior oblique (without affecting other functions of the oculomotor nerve) are quite rare.

"Overaction" of the inferior oblique muscle is a commonly observed component of childhood [[strabismus]], particularly infantile [[esotropia]] and [[exotropia]].  Because true hyperinnervation is not usually present, this phenomenon is better termed "elevation in adduction".
* {{cite journal | author = Kushner BJ | title = Multiple mechanisms of extraocular muscle 'overaction' | journal = Arch Ophthalmol | volume = 124 | issue = 5 | pages = 680-8 | year = 2006 | id = PMID 16682590}}

Surgical procedures of the inferior oblique include: loosening ([[recession]]), [[myectomy]], marginal myotomy, and denervation and extirpation.

==Additional images==
<gallery>
 Image:Gray890.png|Dissection showing origins of right ocular muscles, and nerves entering by the superior orbital fissure.
</gallery>

==External links==
* {{MuscleLoyola|io}}
* {{GPnotebook|-133824433}}
* {{SUNYAnatomyFigs|29|01|08}}
* {{eMedicineDictionary|inferior+oblique+muscle}}
* {{NormanAnatomy|lesson3}} ({{NormanAnatomyFig|orbit5}})
* [http://www.childrenshospital.org/cfapps/research/data_admin/Site339/Images/anat1.gif Image at childrenshospital.org]

{{Gray's}}
{{Muscles of head}}

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

[[de:Augenmuskeln#Musculus_obliquus_inferior]]
[[hu:Musculus obliquus inferior bulbi]]
[[nl:Musculus obliquus inferior]]
[[ja:下斜筋]]
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