Extrinsic Eye Muscles (MT) Flashcards
What extrinsic eye muscles are innervated by the upper division of CN III?
- Levator Palpebrae
2. Superior Rectus
What extrinsic eye muscles are innervated by the lower division of CN III?
- Inferior Rectus
- Medial Rectus
- Inferior Oblique
What extrinsic eye muscle isinnervated by CN VI?
Lateral Rectus
What extrinsic eye muscle is innervated by CN IV?
Superior Oblique
Levator Palpebrae Superioris Origin and insertion
Origin:
- Lesser Wing of Sphenoid
Insertion:
- Superior Tarsal Plate
- Skin of Eyelid
Superior Rectus Origin and insertion
Origin:
- Common Tendinous Ring
Insertion:
- SUPERIORLY on the anterior hemisphere of the eyeball
Inferior Rectus Origin and insertion
Origin:
- Common Tendinous Ring
Insertion:
- INFERIORLY on the anterior hemisphere of the eyeball
Medial Rectus Origin and Insertion
Origin:
- Common Tendinous Ring
Insertion:
- MEDIALLY on the anterior hemisphere of the eyeball
Lateral Rectus Origin and Insertion
Origin:
- Common Tendinous Ring
Insertion:
- Laterally on the anterior hemisphere of the eyeball
Superior Oblique Origin and Insertion
Origin:
Body of Sphenoid
Insertion:
Lateral Posterior Quadrant of the Eyeball
Inferior Oblique Origin and Insertion
Origin:
Medial Floor of Orbit Posterior to rim
Insertion:
Lateral Posterior Quadrant of Eyeball
Levator Palpebrae Innervation and Action
Innervation:
- CN III, Upper Division
Action:
- Elevate Upper Eyelid
Superior Rectus Innervation and Action
Innervation:
- CN III, Upper Division
Action:
- Elevation, Adduction, Intorsion of eyeball
Inferior Rectus Innervation and Action
Innervation:
- CN III, Lower Division
Action:
- Depression, Adduction, Extorsion of eyeball
Medial Rectus Innervation and Action
Innervation:
- CN III, Lower Division
Action:
- Adduction of Eyeball
Lateral Rectus Innervation and Action
Innervation:
- CN VI
Action:
- ABduction of eyeball
Superior Oblique innervation and Action
Innervation:
- CN IV
Action:
- Depression, abduction, intorsion of eyeball
Inferior Oblique Innervation and Action
Innervation:
- CN III, lower division
Action:
- Elevation, abduction, extorsion of eyeball
What muscles are at work in intorsion of the eyeball?
- SUPERIOR Rectus
2. SUPERIOR Oblique
What muscles are at work in extorsion of the eyeball?
- INFERIOR Rectus
2. INFERIOR Obique
What muscles are at work in ABduction of the eyeball?
- superior OBLIQUE
- inferior OBLIQUE
- LATERAL Rectus
What muscles are at work in ADuction of the
- medial RECTUS
- Lateral RECTUS
- inferior RECTUS
What muscles originate from the common tendinous ring?
Superior, Inferior, Medial, and Lateral rectus (aka ALL of the rectus muscles)
What muscles insert on the anterior hemisphere of the eye?
ALL of the rectus mm.
What muscles Insert on the lateral posterior Quadrant of the Eyeball?
Superior and Inferior Oblique mm.
What muscles elevate the eyeball?
Superior Rectus
Inferior Oblique
What muscles depress the eyeball?
Inferior Rectus
Superior Oblique
