Muscles of Eye, Thorax, and Abdominal Wall Flashcards
Which muscle moves the eye up?
Superior rectus
Which muscle moves the eye down?
Inferior rectus
Which muscle moves the eye laterally?
Lateral rectus
Which muscle moves the eye medially?
Medial rectus
How does the superior oblique move the eye?
Rotates the eye down, and lateral
How does the inferior oblique move the eye?
Rotates the eye up and lateral
How is the superior oblique innervated?
By CN IV, Trochlear
How is the lateral rectus innervated?
By CN VI, Abducens
What is the name of CN III? What does it innervate?
Oculomotor, Sup/Inf Rectus; Medial Rectus, inferior oblique
What muscles are used for inspiration (generally)?
The diaphragm and external intercostals
What is used for normal expiration?
The “elastic recoil” of elastic fibers within lung tissue
How is the diaphragm innervated? (nerve and plexus?)
Phrenic nerve
Cervical plexus
What shape is the diaphragm?
A large, dome-shaped muscle
The diaphragm is the between the ________ and _______ cavities.
Thoracic
Abdominal
The dome (of diaphragm) changes shape this way when we breathe in
Flattens
What is the prime mover of inspiration?
The diaphragm
How many pairs of external and internal intercostal muscles are there?
11
The external intercostals help inspiration or expiration?
Inspiration
The external intercostals elevate the _______ with help form the scalenes.
Ribs
Where is the scalenes?
In general, form transverse processes of c-vertebrae to ribs 1,2
What does the scalenes do upon inspiration?
Elevates ribs 1 and 2
What happens if only one side of the scalenes is used?
Flex head and rotate neck
What do the internal intercostals do?
Depress ribs
The internal intercostals are ______ to the external intercostals
Deep
The internal intercostals are synergistic with the _____ _______.
Quadratus lumborum
What are the origin and insertion of the quadratus lumborium?
Iliac crest to transverse processes of L1-L4 and rib 12
How is the quadratus lumborium a fixator?
It fixes rib 12
How is the quadratus lumborium an extensor?
When not used for breathing, can bilaterally extend spine
What happens if the quadratus lumborium is flexed ipsilaterally?
Lateral flex
When are the muscles of the abdominal wall used?
During forced expiration
What does the rectus abdominis do?
Depresses ribs, flexes spine, and compresses abdomen
The rectus abdominis is segmented by ______ ______.
Tendinous intersections
What are the tendinous intersections of the rectus abdominis?
The lines that give a 6 pack
Where does the rectus abdominis go?
From the rib cage to the pubic crest
What does the external abdominal oblique do?
Depresses ribs, flexes spine, and compresses abdomen
How do the fibers of the external abdominal oblique run?
Diagonally, like external intercostals (think hands in pockets)
What does the internal abdominal oblique do?
Depresses ribs, flexes spine, and compresses abdomen
How do the fibers of the internal abdominal oblique run?
Diagonally, like internal intercostals
The internal abdominal oblique is _______ to the external abdominal oblique.
Deep
What does the transversus abdominis do?
Compresses abdomen
How do the fibers of the transverses abdominis run?
Horizontally
What is the linea alba?
A tendinous line that runs from sternum to pubic symphysis, midline, not muscle
