Card Set Information
Ant and Post muscles
How does movement occur in a muscular system?
when the muscle exerts a force on the structure into which it is inserted and pulls it toward its point of origin
What are the msucles of anterior and posteior thorax important for? (2)
-attach upper limb to the axial skeleton via pectoral girdle
-stabilize the shoulder and move the scapula
what are the 6 msucles of the anterior thorax?
pectoralis minor) where is the origin of the pectoralis minor?
it is on ribs 3 thru 5
pectoralis minor) where is the insertion ?
it is on the coracoid process
*bc of this, it pulls the coracoid process down to the ribs
pectoralis minor) what is the pectoralis minor innervated by?
medial pectoral nerve
pectoralis minor) if the scapula is stabilized by other muscles and the pectoralis minor contracts, what happens?
it will lift ribs 3-5 up to help during deep inspiration
pectoralis minor) what artery passes below the pectoralis minor?
pectoralis minor) what else does pectoralis minor do?
stabilize the scapula
serratus anterior) is this a protractor or retractor of the scpula?
serratus anterior) what is a nickname for serratus?
serratus anterior) what is this strucutre needed for?
to elevate the arm above 90 degrees
serratus anterior) does this structure also rotate the scapula laterally or medially to raise the glenoid cavity to raise the arm above 90 degrees?
serratus anterior) where is the origin?
on the anterior lateral aspects of ribs 1 thru 8
serratus anterior) where is the insertion of serratus anterior?
medial border of the scapula
*it wraps around to the posterior side from the anterior origin and inserts on the medial border, deep to the scapula
serratus anterior) what is it innervated by?
long thoracic nerve
*a branch of the brachial plexus
subclavius) Under what structure is the subclavius located?
subclavius) what 2 things does it do?
-holds clavicle in sternoclavicular joint
-protects underlying subclavian vessels
subclavius) where is the origin?
coastal cartilage of rib 1
subclavius) where is the insertion?
inferior surface of the lateral 1/3 of clavicle
subclavius) what innervates it?
nerve of subclavius
*a branch of the brachial plexus
subclavius) what is the action of the subclavius?
is to stabilize the pectoral girdle and help to depress the shoulder
sternocleidomastoid) what does it attach?
the pectoral girdle to axial skeleton
sternocleidomastoid) where does it insert?
to the mastoid process of the temporal bone
sternocleidomastoid) what is it innervated by?
cranial nerve 11 called spinal accesory nerve
sternocleidomastoid) where is the origin for the clavicular head?
medial 1/3 of the clavicle
sternocleidomastoid) what is the origin for the sternal head?
manubrium of the sternum
sternocleidomastoid) (action) what happens during bilateral?
flexes head forward
*both sides contract
sternocleidomastoid)(action) what happens unilateral?
it will turn the face the opposite side and bend the head laterally
scalenes) what strucutre is the anterior scalene deep to?
scalenes) where is the origin?
cervical vertebrea 3/4 thru 6 on the transverse process
scalenes) where is the insertion?
to the first rib
scalenes) what is the action (2)
flex the neck or elevate the rib
scalenes) which artety passes deep to it?
scalenes) what is it innervated by?
cervical spinal nerve
scalenes) how many diferent types are there of these?
scalenes) if the neck is fixed...
it will help elevate the ribs as in deep inspiration during extensive exercises
scalenes) if the ribs are fixed then...
it will help to flex the neck forward
scalenes) what happens during bilateral?
the head will come forward with the neck
scalenes) what happens during unilateral?
it will pull the neck to that side
which muscle covers the sternocleomastoid?
scalenes) does it help to rotate it?
what are the 4 msucles of posterior thorax?
-rhomboid major and minor
trapezius) what does this structure attch?
the pectoral girdle to the trunk
trapezius) what are the 3 origins?
-spinous process of C7 through all of the thoracic vertebra
trapezius) what is it innervated by?
cranial nerve 11 called spinal acessory nerve
trapezius) where is the insertion (3)
-continuous insertion along the acromion and spine of the scapula and lateral third of the clavicle
trapezius) what do weakness of this msucle ccause?
trapezius) what action does the upper fibers do?
elevates the scapula
*pulls up towards the skull
trapezius) what action do middle fibers cause?
retracts the scapula
*they do this by working with rhomboid muscles
trapezius) what action do lower fibers cause/
*helps stabilize it
levator scapulae) what is the origin?
transverse process of the c1 thru 4 vertebrea
levator scapulae) what is the insertion?
upper medial border of the scapula near superior angle
levator scapulae) what innervates it?
dorsal scapular nerve
levator scapulae) what is the main action?
levator scapulae) if the scapula is fixed then..
it will pull the neck posteriorly (extend)
levator scapulae) if both contract (bilateral) then..
the head will go back (extend)
levator scapulae) if its a unilateral action then...
the levator will flex the neck laterally to the same side
are the rhomboid major and minor clearly separated?
rhomboids) location of minor
-at the level of the scapular spine
rhomboids) which is superior ?
rhomboids) which is wider?
rhomboids) are they superficial or deep to the trapezius?
rhomboids) where do both extend from?
vertebrae to scapula
rhomboids) what is the origin of the minor?
spinous process of C7 or T1
rhomboids) where is the origin for major?
spinous process of T2 thru T5
rhomboids) what are both innervated by?
dorsal scapular nerve
rhomboids) what two actions do they do?
-help pull scapula downward
rhomboids) insertion of minor
medial side of scapula
*at about the level of the spine
rhomboids) insertion of the major
just inferiro to the minor and all the way down to inferior angle of scapula