The Axilla & Brachial Plexus II Flashcards
upper lesions of the brachial plexus:
___ palsy
usually caused by an excessive increase in the angle b/n the ___ & ___
results in excessive ___ & ___ (___) of the nerve roots C5 & C6
examples:
- newborns during a difficult ___
- adults following a severe blow or fall on the ___
erb-duchenne
neck & shoulder
traction & tearing (avulsion)
- delivery
- shoulder
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
nerves (4)
suprascapular nerve
nerve to the subclavius
musculocutaneous nerve
axillary nerve
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
muscles:
suprascapular nerve (2)
nerve to the subclavius (1)
musculocutaneous nerve (3)
axillary (2)
supraspinatous
infraspinatous
subclavius
biceps brachii
brachialis
coracobrachialis
deltoid
teres minor
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
suprascapular nerve:
action(s):
supaspinatous m
infraspinatous m
abductor of the arm at the shoulder
lateral rotator of the arm at the shoulder
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
nerve to the subclavius:
action(s):
subclavius m
depresses the clavicle
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
musculocutaneous nerve:
action(s):
biceps brachii
brachialis
coracobrachialis
supinator of forearm
flexor of forearm at the elbow
weak flexor of arm at the shoulder
chief flexor of forearm at elbow
flexes arm at shoulder
upper lesions of the brachial plexus:
nerve lesions & muscle paralysis may involve the following:
axillary nerve:
action(s):
deltoid
teres minor
abductor of arm at shoulder
lateral rotator of arm at shoulder
upper lesions of the brachial plexus:
result:
the upper limb hangs ___ by the side, medially ___ by the unopposed action of the ___ muscle
the forearm is ___ due to loss of action of the ___ (supination of the forearm)
loss of sensation along the (medial/lateral) side of the limb
“___” position
limply
rotated
pectoralis major muscle
pronated
biceps
lateral
waiter’s tip position
lower lesions of the brachial plexus:
___ palsy
traction injuries caused by excessive (abduction/adduction) of the arm
results in ___ (___) of the C& & T1 roots of the plexus
the nerve most affected is the ___ nerve which supplies most of the small muscles of the ___
klumpke’s palsy
abduction
tearing (avulsion)
ulnar nerve
hand
lower lesions of the brachial plexus:
examples:
newborn: forceful pull of the ___ limb during a difficult ___
child falling from a ___ (e.g., tree), clutching an object (single/double) handed (e.g., tree branch) to stop the fall
upper limb
delivery
height
single handed
lower lesions of the brachial plexus:
result:
the hand has a ___ appearance caused by hyperextension of the ___ joints & flexion of the ___ joints
the ___ is unopposed by the lumbricals & interossei & extends the ___ joints
the ___ & lateral portion of the ___ are unopposed by the lumbricals & interossei & flex the middle & terminal ___ respectively
in addition, loss of sensation will occur along the (medial/lateral) side of the upper limb
clawed
metacarpophalangeal joints
interphalangeal joints
extensor digitorum
metacarpophalangeal joints
flexor digitorum superficialis
flexor digitorum profundus
phalanges
medial
lesion of the long thoracic nerve:
the long thoracic nerve (C5, C6, C7) may be injured by blows or pressure on the (anterior/posterior) triangle of the neck, ___ wounds, during a ___ surgical procedure, or ___ injuries
posterior
stab
mastectomy
athletic
lesion of the long thoracic nerve:
paralysis of the ___ muscle
the medial border of the ___ becomes prominent & protrudes (anteriorly/posteirorly) when someone pushes against a fixed object (___)
serratus anterior muscle
scapula
posteriorly
winging of the scapula
lesion of the long thoracic nerve:
since the ___ can no longer be fixed to the (anterior/posterior) chest wall, the ___ is seriously weakened
(abduction/adduction) of the arm is seriously impaired b/c of weakened upward rotation of the ___
scapula
posterior
triceps brachii
abduction
scapula
thoracic outlet syndrome (tos):
condition involving compression of ___ nerves, ___ vessels, or both, b/c of an inadequate passageway just above the ___ rib & behind the ___
symptoms include:
- neck, shoulder, & arm ___
- ___
- impaired ___ to the extremeties
brachial plexus nerves
subclavian vessels
first rib
clavicle
- pain
- numbness
- circulation
thoracic outlet syndrome (tos):
brachial plexus trunks & subclavian vessels are subject to compression or irritation as they course through passageways from the base of the neck to the axilla (3)
interscalene triangle (most important)
costoclavicular triangle
subcoracoid space
thoracic outlet syndrome (tos):
interscalene triangle:
muscles:
anterior: ___
posterior: ___
inferior: ___
anterior scalene
middle scalene
medial border of first rib
thoracic outlet syndrome (tos):
costoclavicular triangle:
bones:
anterior: ___
postero-medial: ___
postero-lateral: ___
middle third of clavicle
first rib
upper border of scapula
thoracic outlet syndrome (tos):
subcoracoid space:
beneath the ___ process
just deep to the ___ muscle
coracoid process
pectoralis minor muscle
thoracic outlet syndrome (tos):
___ symptoms occur in 95% of cases
C8 & T1 nerve roots most commonly involved producing ___ & ___ along the ___ nerve distribution
neurologic symptoms
pain
paresthesia
ulnar nerve
axillary artery:
direct continuation of the ___ artery
extends from the (medial/lateral) border of the ___ rib to the (superior/inferior) border of the ___ muscle
subclavian artery
lateral border of the first rib
inferior border of the teres major muscle
axillary artery:
divided into three parts by the ___ muscle:
- first part: (above/below) the muscle
- second part: (in front of/behind) the muscle
- third part: (above/below) the muslce
by convention, the medial, lateral, & posterior cords of the ___ plexus are amed according to their relationship to the ___ segment of the axillary artery
pectoralis minor muscle
- above
- behind
- below
brachial plexus
middle segment
branches of the axillary artery:
first part (1)
second part (2)
third part (3)
superior (supreme) thoracic artery
thoracoacromial trunk
lateral thoracic artery
subscapular artery
anterior & posterior circumflex humeral arteries
branches of the axillary artery:
first part:
superior (supreme) thoracic artery:
helps supply the ___ & the ___ muscle
first two intercostal spaces
serratus anterior muscle
branches of the axillary artery:
second part:
thoracoacromial trunk:
arises beneath the ___ muscle
passes above the upper border of the ___ muscle
pierces the ___ fascia
gives off regional branches
pectoralis minor muscle
pectoralis minor
clavipectoral fascia
branches of the axillary artery:
second part:
lateral thoracic artery:
arises beneath the ___ muscle
passes below the ___ muscle running along the (medial/lateral) side of the ___
pectoralis minor m
pectoralis minor m
lateral
thorax
branches of the axillary artery:
second part:
lateral thoracic artery:
formerly called the ___ artery b/c it’s a chief source of blood supply to the breast
also supplies:
- ___ m’s
- ___ m
- contents of the ___
external mammary artery
pectoral m’s
seratus anterior m
axilla
branches of the axillary artery:
third part:
subscapular artery:
passes (upward/downward) & (forward/backward)
divides into two main trunks (2)
downwrad
backward
circumflex scapular artery
thoracodorsal artery
branches of the axillary artery:
third part:
subscapular artery:
circumflex scapular artery:
passes around the (medial/lateral) border of the ___
b/n the ___ & ___ m in the ___ space
lateral border
scapula
scapula
teres major m
triangular space
branches of the axillary artery:
third part:
thoracodorsal artery:
passes (upward/downward) along the ___
joined by the ___ n
both supply the ___ m
downward
axilla
thoracodorsal n
latissimus dorsi m
branches of the axillary artery:
third part:
anterior & posterior circumflex humeral arteries:
posterior circumflex humeral artery is (smaller/larger)
they pass around the surgical neck of the ___ & anastomose w/ ___
posterior circumflex runs in the ___ space w/ the ___ n
larger
humerus
anastomose
quadrangular space
axillary n
axillary vein:
direct continuation of the ___ vein as it crosses the lower border of the ___ muscle
tributaries (3)
basilic vein
teres major muscle
venae comitantes of the brachial artery
cephalic vein
tributaries corresponding to the branches of the axillary artery
