Pectoral Region and Axilla Flashcards
origin of pectoralis major?
clavicular head: medial 1/2 of clavicle sternoclavicular head: sternum, costal cartilatges, aponeurosis of external abdominal obluique
insertion of pectoralis major?
lateral lip of intertubercular sulcus
action of pectoralis major?
flexes, adducts and medially rotates arm
innervation of pectoralis major?
medial and lateral pectoral nerve
specific function of clavicular head of pectoralis major?
flexes an all the way extended arm
specific function of sternocostal head of pectoralis major?
extends a flexed arm
origin of pectoralis minor?
ribs 3-5 near costal cartilages
insertion of pectoralis minor?
coracoid process of scapula
action of pectoralis minor?
stabilizes scapula by pulling it inferior and anterior
innervation of pectoralis minor?
medial pectoral nerve (C8, T1)
origin of subclavius?
rib 1 near costal cartilage
insertion of subclavius
middle 1/3 of clavicle
action of subclavius?
anchors and depresses clavicle
innervation of subclavius?
nerve to subclavius (C5,C6)
where is the clavipectoral fascia?
deep to pectoralis major, invests to pectoralis minor and subclavius
origin of serratus anterior?
ribs 1-8 or 9
insertion of serratus anterior?
medial border of scapula (anterior surface)
action of serratus anterior?
protracts scapula, upward rotation of glenoid, helps keep medial border and inferior angle opposed to thoracic wall (holds scapula to thoracic wall)
innervation of serratus anterior?
long thoracic nerve (is on the superficial surface of the muscle)
what could happen if the long thoracic nerve is damaged?
the serratus anterior could be paralyzed, causing winging of the scapula (protrusion of scapula away from the thoracic wall) (ask patient to push on a wall with outstretched arm)
what makes up the anterior wall of the axilla?
pectoralis major, pectoralis minor, subclavius, clavipectoral fascia
what makes up the lateral wall of the axilla?
intertubercular sulcus
what makes up the posterior wall of the axilla?
subscapularis, teres major, teres minor, latissimus dorsi, long head of triceps
what makes up the floor of the axilla
skin of the armpit
what makes the medial wall of the axilla?
upper thoracic wall, serratus anterior
what makes the inlet of the axilla?
lateral margin of rib 1, clavicle, superior margin of scapula to coracoid process
what goes through the inlet of the axilla
axillary sheath surrounding arteries, veins, nerves, lymphatics
what is the first division of the axillary artery?
from the lateral border of the first rib to the medial border of the pectoralis minor
what is the second division of the axillary artery?
from the medial border of the pectoralis minor to the lateral border of the pectoralis minor
what is the 3rd division of the axillary artery?
lateral border of pectoralis minor to the lateral border of the latissimus dorsi
what are the 4 branches of the thoracoacromial artery?
pectoral, deltoid, acromial, clavicular
trace the flow of blood back to the heart from the upper arm
brachial vein, basilic vein, axillary vein, subclavian vein
or the cephalic vein to the subclavian vein
3 common sites for swollen lymph nodes?
cervical, axilla, inguinal
trace the flow of lymph from the base of the axilla?
humeral, pectoral and subscapular nodes all drain the the central node, which drains to the apical node, to the infraclavicular node, to the subclavian lymphatic trunk to the right lymphatic duct
what is in the triangular space?
triceps long head (base)
teres major (bottom)
teres minor (top)
circumflex scapular artery through center
what is in the quadrangular space
teres minor (top)
teres major (bottom)
triceps long head (left)
humerus (right)
posterior circumflex humeral artery (center)
axillary nerve (center)
what is in the triangular interval
teres major (base)
triceps long head (left)
humerus (right)
profunda brachii (center)
radial nerve (center)
blood supply serratus anterior
lateral thoracic artery
how to test the suprascapular nerve
abduction (supraspinatus), lateral rotation (infraspinatus) of arm
palpate muscles while testing against resistance
what does superior subscapular nerve innervate?
subscapularis
what does the middle subscapular nerve innervate?
latissimus dorsi
what does the inferior subscapular nerve innervate?
subscapularis, teres major
how to test subscapular nerve
medial rotation, adduction of arm
where is the landmark of the subscapular nerves?
subscapular fossa
landmark of suprascapular nerve
suprascapular notch
landmark of long thoracic nerve
midaxillary line
landmark for dorsal scapular nerve
medial border of scapula
how to test medial pectoral nerve
flexion of adduction of arm while palpating muscle
landmark for medial pectoral nerve
pierces pectoralis minor
testing for lateral pectoral nerve
flexion or adduction of arm while palpating muscle
what vessel supplies pec major
pectoral branch of thoracoacromial trunk
what is the landmark for lateral pectoral nerve
passes medial pectoral nerve (along its superior border) to pectoralis minor
what does the axillary nerve supply?
deltoid, teres minor, skin over deltoid
testing for axillary nerve
abduction over 15 degrees, palpate muscle while testing actions against resistance
blood supply deltoid and teres minor
posterior circumflex humeral artery
landmark for the axillary nerve
surgical neck of humerus
landmark for radial nerve
radial groove/midshaft humerus
what does the radial nerve supply?
extensor muscles of arm and forearm, skin of posterior arm, forearm and much of dorsal hand
how to test radial nerve
extension at elbow, wrist, MCP joints, against resistance
skin area tested for radial nerve
dorsal surface of hand between 1st and 2nd metacarpals, posterior skin of arm and forearm
what is the cause of wrist drop?
problem with radial nerve
what damage could be caused by a mid shaft fracture
damage to radial nerve in the radial groove of the humerus, leading to wrist drop
symptoms of wrist drop
paralysis of wrist and finger extendors in the posterior compartment, loss of cutaneous innervation over posterior forearm and dorsum of han = damage to radial nerve
describe saturday night palsy
posterior cord of brachial plexus is compressed or injured in the axilla. results in wrist drop (radial nerve innervation), inability to abduct arm beyond 15 degrees (axillary nerve innervation) and possible weakened glenohumeral movements (subscapular nerve innervation) (subscapularis, teres major, lat dorsi)
what cutaneous area does the musculocutaneous nerve innervate
lateral forearm
cutaneous and motor tests for musculocutaneous nerve
lateral forearm, flexion at elbow
landmark for musculocutaneous nerve
pierces coracobrachialis
describe Erb’s palsy
damage to the superior roots of the brachial plexus C5 and C6 or the superior trunk due to excessive lateral flexion of the neck or difficulties during delivery (shoulder dystocia)
damage causes partial or complete paralysis of muscles supplied by the suprascapular nerve, musculocutaneous nerve, and axillary nerve.
what muscles could be weakened or paralyzed due to Erb’s Palsy (damage to C5, C6)
supraspinatus, infraspinatus
deltoid, teres minor
biceps, brachialis
pectoralis major (clavicular head)
supinator
symptoms of erb’s palsy
waiter’s tip position, adducted and medially rotated arm, extended and pronated forearm, flexed hand
DUE TO LOSS OF ROTATOR CUFF INNERVATION, INCREASED RISK FOR SHOULDER DISLOCATION
what does the median nerve supply
thenar muscles (abductor pollicis brevis,flexor pollicis brevis, opposens pollicis), lateral 2 lumbricals, muscles of forearm EXCEPT FLEXOR CARPI ULNARIS AND MEDIAL 1/2 OF FLEXOR DIGITORUM PROFUNDUS), skin of lateral 2/3 of hand
how to test median nerve
pronation of forearm, opposition/flexion of thumb, flexion at wrist (look for ulnar deviation during hand flexion), flexion of fingers at PIP joints
common lesion name for median nerve damage
hand of benediction
cutaneous test for median nerve
tip of index finger
landmark for median nerve
cubital fossa, carpal tunnel
cutaneous innervation of median nerve
lateral 2/3 of anterior hand and fingertips of digits 1, 2, 3.5 on dorsum
what causes median nerve palsy
compression or injury of median nerve at wrist (carpal tunnel syndrome) can cause sensory loss in regions supplied by palmar digital branches and paralysis of thenar muscles
symptoms median nerve palsy
weakened or loss of thumb opposition and eventually wasting of the thenar eminence = APE HAND
dr cuMA
what causes the hand of benediction
compression of median nerve at the cubital fossa or proximally, causes loss of innervation to all the muscles in the anterior forearm EXCEPT FOR FLEXOR CARPI ULNARIS AND THE MEDIAL 2 BELLIES OF THE FLEXOR DIGITORUM PROFUNDUS
symptoms of hand of benediction
when asked to make a fist, only digits 4+5 flex, 1,2,3 cannot.
also sensory loss to lateral 2/3 of anterior hand and fingertips of digits 1,2,3
what does the ulnar nerve innervate
flexor carpi ulnaris
medial half of flexor digitorum profundus
hypothenar musles (flexor digiti minimi brevis, opponens digiti minimi, abductor digiti minimi)
medial 2 lumbricals
interossei muscles
adductor pollicis
cutaneous innervation of ulnar nerve
skin of medial 1/2 of hand (dorsal and anterior)
(dorsal branch = dorsal)
(palmar branch = palmar)
how to test ulnar nerve
abduction and adduction of digits, flexion of wrist (look for radial deviation during hand flexion)
what is the common lesion name for ulnar nerve damage
claw hand
dr CUma
cutaneous test for ulnar nerve
tip of pinkie finger
landmark for ulnar nerve
medial epicondyle (cubital tunnel)
hook of hamate/pisiform (guyon’s canal)
what is guyon’s canal
fibro-osseous tunnel between palmar carpal ligament and flexor retinaculum
what is guyon’s canal syndrome or cyclist’s palsy
compression of ulnar nerve at the WRIST at guyon’s canal, leading to paralysis of hypothenar muscles, 2 medial lumbricals, interossei, and adductor pollicis
symptoms of guyon’s canal syndrome
inability to adduct the digits, abduct digits 2-5 and fine motor movement of fingers
what causes claw hand
compression of the ulnar nerve at the elbow, leading to paralysis of the flexor carpi ulnaris, medial 2 bellies of flexor digitorum profundus, hand muscles,
symptoms of claw hand or partial claw hand
difficulty making a fist, radial deviation during wrist flexion, partial claw hand where MCP joints are extended and the PIP/DIP joints are flexed for digits 4+5
what is klumpke’s palsy
damage to C8 or T1 roots affect muscles innervated by median and ulnar nerves.
caused by pulling the arm during delivery, hanging by one arm, severe pulling of the arm from above
presents as FULL CLAW HAND
drCUM a
what cutaneous innervation does the radial nerve supply
dorsal 1/2 of hand except fingertips of digits 1,2,3
also area where the abductor pollicis brevis and flexor pollicis brevis would be
what cutaneous area does the medial cutaneous verve of the arm supply
medial area of upper arm
what cutaneous area does the medial cutaneous nerve of the forearm supply
medial half of forearm (anterior)
what is colley’s fracture and what can it do
fracture of distal radial head, damages median nerve
