Brachial Plexus Flashcards
name the two joints of the clavicle
acromioclavicular joint
sternoclavicular joint
what is the sternoclavicular joint betwee?
clavicle and manubrium of sternum
what is a common fracture for babies
clavicle fractures
name the four ligaments that help stabilize the sternoclavicular joint
anterior and posterios sternoclavicular joints
costoclavicular joints
interclavicular joints
what is the costoclavicular joint in between?
anchors sternal end of the clavicle to the first rib
what is the AC joint surrounded by?
loose fibrous capsule
name the two ligaments that help stabilize the AC joint
acromioclavicular ligament
coracoclavicular ligament
what are the two parts of the coracoclavicular ligament that helps the AC joint?
trapezoid and conoid ligaments
what is a 1st degree AC injury?
stretch or tear of AC ligament
what is a 2nd degree AC injury?
rupture of AC ligament
what is a 3rd degree AC injury? another name?
shoulder separation…AC and coroclavicular ligaments are torn
what can you see externally with a 3rd degree AC injury or shoulder separation?
prominent clavicle on superior aspect of shoulder
what nerves innervate the pec major?
medial and lateral pectoral nerves
what are two actions of pec major?
medial rotation and adductor/flexor of arm
where does pec major insert?
bicipital groove on humerus
where does pec minor insert?
coracoid process of scapula
where does pec minor originate?
3-5 ribs
what is the action of the pec minor?
stabilization of the scapula against the thoracic wall
what is innervation of the pec minor?
medial pectoral nerve
what three important things pass below the pec minor?
axillary artery
axillary vein
brachial plexus
what does the axillary artery continue off of?
the subclavian artery after passing the lateral margin of the first rib
what does the axillary artery become named as it continues into the arm?
brachial artery
name the six branches of the axillary artery
superior thoracic thoracoacromial trunk lateral thoracic artery subscapular anterior humeral circumflexx posterior humeral circumflex
the first part of the axillary artery consists of what branch?
superior thoracic
the second part of the axillary artery consists of what two branches
thoracoacromial trunk
lateral thoracic artery
the 3rd part of the axillary artery consists of what three branches
subscapular
anterior humeral circumflexx
posterior humeral circumflex
what does the superior thoracic artery provide flow to?
1st and 2nd intercostal rib spaces
name the four regions that the thoracoacromial trunk provides blood flow to
deltoid
acromial
pectoral
clavicular
what two things does the lateral thoracic provide blood flow to?
pectoral muscles and breast
if the axillary artery is blocked, where does arm get blood flow?
from anastamoses around the scapula
name the five segments of the brachial plexus in order
roots trunks divisions cords branches
the roots of the brachial plexus come from what spinal nerves
ventral rami of C5 through T1
how many trunks do the five roots converge to make in the brachial plexus?
three
name the three trunks of the bracial plexus
superior
middle
inferior
what nerve roots make up the superior trunk of the brachial plexus?
C5 and 6
what nerve roots make up the middle trunk of the brachial plexus?
C7
what nerve roots make up the inferior trunk of the brachial plexus?
C8 and T1
how do the trunks of the brachial plexus divide?
into anterior and posterior divisions
the anterior divisions of the brachial plexus feed what muscles?
anterior flexors
the posterior divisions of the brachial plexus feed what muscles?
posterior extensors
the anterior and posterior divisions then form what? how many?
3 cords
name the 3 cords of the brachial plexus?
lateral
medial
posterior
name the two divisions that feed into the lateral cord
anterior divisions of superior and middle trunk
name the divisions that feed into the medial cord
anterior division of the inferior trunk continues
name the three divisions that feed into the posterior cord
posterior divisions from the superior, middle and inferior trunks
name the five main branches (nerves) that arise from the cords of the brachial plexus
musculocutaneous axillary radial median ulnar
what two nerves/branches come from the posterior cord?
radial and axillary
what two nerves/branches come from the lateral cord?
musculocutaneous and lateral root of the median nerve
what two nerves/branches come from the medial cord?
ulnar nerve and medial root of median nerve
what does the musculocutaneous nerve innervate?
flexors of the arm
what does the axillary nerve innervate?
deltoid and teres minor
what does the ulnar nerve innervate?
intrinsic muscles of the hand and some forearm flexors
what does the radial nerve innervate?
innervates the extensors of the arm and forearm
what does the median nerve innervate?
most forearm flexors and thumb muscles
the musculocutaneous arises from what spinal nerves?
C567
the axillary arises from what spinal nerves?
C56
the radial arises from what spinal nerves?
C5678 T1
the median arises from what spinal nerves?
C5678 T1
the ulnar arises from what spinal nerves?
C7,8 and T1
name the three subscapular nerves
upper middle and lower
name the nine smaller branches of the brachial plexus to know
long thoracic dorsal scapular suprascapular upper subscapular middle subscapular lower subscapular medial pectoral lateral pectoral medial cutaneous nerves of arm/forearm
the roots of the brachial plexus travel through what two parts of the neck?
anterior and middle scalene
what is the name of the fascia that surrounds the scalene muscles? what does it have to help with the brachial plexus?
prevertebral fascia…has an axillary sheath that covers the plexus
other than the brachial plexus, what does the axillary sheath extending from the prevertebral fascia cover?
axillary artery
what are the spinal nerves of the upper subscapular?
C56
what are the spinal nerves of the middle suubscapular?
C567
what are the spinal nerves of the lower subscapular?
C56
what are the spinal nerves of the suprascapular?
C56
what are the spinal nerves of the dorsal scapular?
C5
what are the spinal nerves of the medial pectoral?
C8T1
what are the spinal nerves of the lateral pectoral ?
C5-C7
what are the spinal nerves of the medial cutaneous nerves of the arm/forearm?
C8T1
what is the action of the medial cutaneous nerves of the arm/forearm
sensation to the medial arm and forearm
what two muscles does the lower subscapular innervated?
teres minor and subscapularis muscle
what muscle does the upper subscapular innervate
subscapularis
what muscle does the middle subscapular innervate?
lattisimus dorsi
what two muscles does the suprascapular nerve innervate?
supraspinous and infraspinous
where do the cords of the brachial plexus run along?
axillary artery
describe the location of each cord of the brachial plexus in relation to the axillary artery
lateral is lateral to it
medial is medial to it
posterior is posterior to it
name the only nerve of the upper limb that does not come from the brachial plexus
intercostobrachial nerve
what is the innervation of the intercostobrachial nerve?
sensory innervation to small region of skin along the medial aspect of the arm
sensory innervation of thumb and lateral arm is what dermatome?
C6
sensory innervation of the tip of shoulder is what dermatome?
C5
sensory innervation of the middle finger is what dermatome?
C7
sensory innervation of the little finger is what dermatome?
C8
sensory innervation of the medial arm is what dermatome?
T1