Module 4C: Upper Appendicular Muscles Flashcards
what are the appendicular muscles?
muscles that move and attach to the limb
if some appendicular muscles can attach to the axial skeleton, why are they called appendicular muscles?
because they have a direct impact on the appendicular skeletal movement
- so they are grouped with the appendicular muscles
why can the scapula move freely over the thoracis wall?
because there is no ligament attachment to the thorax
what are three movements of the scapula?
- elevation and depression (up and down)
- protraction(adduction) and retraction(abduction) (left and right)
- upward and downward rotation (moving arm up and down) (clockwise and counter-clockwise)
what is the point of reference for upward and downward rotation of the scapula?
the glenoid cavity
- if it points up, it is an upward rotation and if it points down, it is a downward rotation
what is the trapezius?
a shoulder girdle muscle
- looks like a diamond on the back
- has three fibers (superior, middle and inferior)
what is the origin of the trapezius?
- nuchal ligament (ligamentum nuchae)
- spines of thoracic vertebrae
- occipital bone
- ALL THREE, NOT JUST ONE
what is the insertion of the trapezius?
- clavicle (out front)
- acromion process (laterally)
- spine of scapula (back)
what is the action of the trapezius?
- elevate scapula
- adduction/retraction of scapula
- upward rotation of scapula, depression
- shoulder shrug (combination of elevation and adduction of the scapula)
where is the most action of the trapezius?
the scapula
which muscle primarily elevates the scapula?
the levator scapulae
what is the origin of the levator scapulae?
C1-C4 transverse processes
where does most of the back muscles attach to?
spinous processes
what is the insertion of the levator scapulae?
superior angle of scapula
- located superiorly to the spine of the scapula
what is the action of the levator scapulae?
- scapula elevation (if you pull up or contract this muscle, you will pull up on the scapula, causing elevation)
- on ONE side, it will do a clockwise rotation which depresses the glenoid fossa (if you pull up on this medial side, the lateral side will go down(occurs when lowering the arm)
-* elevates medial border of scapula - shoulder shrug with trapezius; downward rotation of scapula
the levator scapulae works with the trapezius muscle for which movement?
the shrug movement
- they both have elevation in common
is the rhomboid minor superior to the rhomboid major?
yes
what is the origin of the rhomboid minor and major?
the spinous processes of C7-T5
what is the insertion of the rhomboid minor and major?
medial border of scapula
- insert lower than the levator scapula
what is the actions of the rhomboid minor and major?
- retraction of scapula
- elevation of scapula
- downward rotation of scapula
what muscle is superficial to the ribs directly and to the intercostal muscles?
the serratus anterior
what is the origin of the serratus anterior?
the lateral surface of ribs 1-9
what is the insertion of the serratus anterior?
- the medial border of scapula, anterior surface
how does the serratus anterior start and then move?
starts deep and moves more superficially