Brachial Plexus Flashcards
What is a plexus?
network of interjoining nerves/ vessels
What are the first 3 dissection steps to see BP?
- reflect pectoralis major
- reflect pectoralis minor
- remove axillary vein/ tributaries
Where is access to the axillary brachial plexus?
deep to anterior wall of axilla
What is the orientation landmark of the brachial plexus?
pectoralis minor inserting on coracoid process
What is the brachial plexus formed from?
anterior rami of spinal nerves C5/C6/C7/C8/T1
Why is there a C8 spinal nerve?
spinal nerves- above vertebrae
What form the roots of the brachial plexus?
anterior rami of spinal nerves C5-T1
What provides innervation to muscles of the upper limb?
brachial plexus
Starting from the spinal cord what are the components of the brachial plexus? (5x)
roots
trunks
divisions
cords
branches
What is the menomic for the 5 parts of the brachial plexus?
Beer Cold Drink To Remember
branches/ cords/ divisions/ trunks/ roots
What part of the brachial plexus does the clavicle pass through?
divisions
What are the cords of the brachial plexus deep to?
insertion of pectoralis minor
How many trunks are there?
3
What are the 3 trunks called?
upper/ middle/ lower
How many divisions are there?
6x- anterior/ posterior (from each trunk)
How many cords are there?
3
What are the 3 cords called- in order superior to inferior?
lateral/ posterior/ medial
What nerves arise from roots/ trunks in the supraclavicular region of the BP? (leave early)
dorsal scapular nerve
long thoracic nerve
suprascapular nerve
nerve to subclavius
What muscles are associated with dorsal scapular nerve?HINT: muscles associated with medial border of scapula
levator scapulae
rhomboid major
rhomboid minor
What muscle is associated with long thoracic nerve?
serratus anterior
What muscles are associated with suprascapular nerve?
suprasoinatus
infraspinatus
What muscle is associated with nerve to subclavius?
subclavius
What are the 2 branches from roots?
Dorsal scapular nerve C5
Long thoracic nerve C5-C7
What are the 2 branches from trunks?
Suprascapular nerve C5/C6
Nerve to subclavius C5/C6
What are the arteries that give blood supply to upper limb?
- in order superior to inferior
subclavian/ axillary/ brachial
How are the cords of the brachial plexus named?
in relation to axillary artery
posterior/ lateral/ medial
Where does pectoralis minor insert?
coracoid process of scapula
What branch arises from the lateral cord?
Musculocutaneous nerve
What branch arises from medial cord?
Ulnar nerve
What branch arises from medial/ lateral cords?
Median nerve
What branches arise from the cords?
superior to inferior
Musculocutaneous nerve
Median nerve
Ulnar nerve
What branches arise from the posterior cord?
axillary nerve
radial nerve
thoracodorsal nerve
upper subscapular nerve
lower subscapular nerve
Where is the posterior cord in relation to pectoralis minor?
deep
How many branches arise from the posterior cord?
5
What muscles are associated with axillary nerve?
deltoid
teres minor
What muscles are associated with radial nerve?
extensors of the upper limb
What muscle is associated with thoracodorsal nerve?
latissimus dorsi
What muscle is associated with upper subscapular nerve?
subscapularis
What muscles are associated with lower subscapular nerve?
subscapularis
teres major
What does the axillary nerve innervate?
deltoid
teres minor
What muscles are associated with lateral root of median nerve?
anterior forearm
hand
What muscles are associated with musculocutaneous nerve?
biceps brachii
brachialis
coracobrachiales
What muscles are associated with lateral pectoral nerve?
pectoralis major
pectoralis minor