Nerve supply: upper limb Flashcards
name the 5 divisions of the brachial plexus:
roots - trunks - divisions - cords - terminal nerves
which spinal nerves make up the brachial plexus:
C5,6,7,8 and T1
brachial plexus position of: roots
- C5 and C6 join
- C7 single
- C8 and T1 join
brachial plexus position of: trunks
superior, middle inferior trunks
brachial plexus position of: divisions
- superior, middle and inferior trunk converge to form posterior
- middle and superior converge
- inferior has another branch
brachial plexus position of: cords
- lateral
- posterior
- medial cord
brachial plexus position of: terminal
- posterior cord forms radial and axillary nerves
- lateral and medial cords join to form median nerve
- lateral cord make musculocutaneous n.
- medial cord form ulnar nerve
M of brachial plexus:
- musculocutaneous
- median n
- ulnar n
where does the clavicle divide the brachial plexus:
diagonally at the divisions
brachial plexus branches off: roots
C5:
- dorsal scapular n,
- cont. to phrenic nerve
C5,6,7 make long thoracic n
brachial plexus branches off: trunks
superior trunk:
- suprascapular n
- nerve to subclavius
brachial plexus branches off: divisions
none
brachial plexus branches off:
lateral cord
lateral cord:
- lateral pectoral n
- musculocutaneous n
brachial plexus branches off: posterior cord
posterior cord:
- axillary
- superior subscapular n
- thoracodorsal n
- inferior subscapular n
brachial plexus branches off: medial cord
medial cord:
- medial pectoral
- medial cutaneous n. of arm
- medial cutaneous n. of forearm
origin and contributions: musculocutaneous n
- lateral cord
- C5, 6, 7 cont
origin and contributions: median nerve
- from medial and lateral cords
- C6, 7, 8 and T1
origin and contributions: radial nerve
- from posterior cord
- C5- T1
origin and contributions: ulnar nerve
- from medial cord
- C8 and T1
origin and contributions: axillary nerve
- posterior cord
- C5, 6
musculocutaneous n: motor supply
muscles: ant compartment of arm
musculocutaneous n: sensory supply
skin, lateral aspect of forearm
median n: motor supply
- muscles: ant com of forearm EXCEPT FCU, medial half of FDP
- thenar mm
- lateral 2 lumbricals
median n: sensory supply
- palmar surface of lateral 3 and half digits
- lateral palm
- middle wrist
ulnar n: motor supply
- FCU
- medial half of FDP
- all intrinsic hand muscles EXCEPT thenar mm and lateral 2 lumbricals
ulnar n: sensory supply
- skin of palmar and dorsal surfaces of 1 and half digits
- associated palm and wrist
axillary n: motor supply
deltoid, teres minor
axillary n: sensory supply
skin over upper and lateral arm
radial n: motor supply
- all muscles in post com of arm/ forearm (even branch to brachialis)
radial n: sensory supply
- skin on posterior arm and forearm
- lower lateral arm
- dorsal lateral surface of hand
eg. injury to brachial plexus
- affects movements and cutaneous sensations in upper limb
- cause by stretching, disease and wound and (excessive increase in angle) posterior triangle high or axilla
- paralysis and anaesthesia
define dermatomes:
- area of skin supplied by single spinal nerve
- overlaps but can be used to test spinal cord/ nerve damage
define myotomes:
- skeletal muscle supplied by single spinal nerve
- more difficult to test
