Review Note
Last Update: 07/30/2024 08:26 AM
Current Deck: 01 Anki Avengers::LEAPMed 01::01ANA::23.2Muscular (Bryan Edition)::01 Head, Neck, and Trunk::Origin
PublishedCurrently Published Content
MuscleName
Superior rectus
OccludedImage
Origin
Origin:
The 4 rectus muscles and the superior oblique arise from a common tendinous ring
(anulus of Zinn) on the body of the sphenoid bone.
The inferior oblique arises from the floor of the orbit.
Insertion
Insertion:
The 4 rectus muscles insert into the sclera, just posterior to the cornea.
The superior oblique muscle passes forward, and its tendon passes through a fibrous ring (trochlea) and inserts into the sclera deep to the superior rectus muscle.
The inferior oblique inserts into the sclera deep to the lateral rectus muscle.
Innervation
Innervation:
The lateral rectus is innervated by the abducent nerve (CN VI);
the superior oblique is innervated by the trochlear nerve (CN IV).
All the other rectus muscles and the inferior oblique are innervated by the oculomotor nerve (CN III).
Actions
Actions: In clinical testing, when the eye is abducted, the superior rectus elevates the globe, and the inferior rectus depresses it. When the eye is adducted, the superior oblique depresses the globe, and the inferior oblique elevates it. The medial rectus is a pure adductor, whereas the lateral rectus is a pure abductor. The anatomic actions differ from the actions tested for clinical evaluation of the muscles.
Attachments
Extra
Plate
Atlas Plate 84
Origin Pictures
Insertion Pictures
Innervation Pictures
Muscle Table
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