Brachial/Cephalic Plexus Flashcards
what spinal cord levels make up the brachial plexus?
C5-T1
brachial plexus supplies the ____ and ____ innervation to the ___ ____
motor and sensory innervation to upper limb
order of brachial plexus (cords, branches, etc.)
roots
trunks
divisions
cords
branches
“Rugby Teams Drink Cold Beverages”
roots of brachial plexus are the ___ ___ of C5-T1
ventral rami
roots = ventral ___
rami
C5-C8 roots course ___ associated vertebrae
above
8 C spinal nerves and only 7 C vertebrae
each brachial plexus root has an associated ____ and ____
dermatome and myotome
how many brachial plexus trunks are there? names?
3
upper (C5-6), middle (C7), lower (C8-T1)
what trunk does the suprascapular nerve branch from?
upper trunk
where do the roots/trunks of the brachial plexus exit?
between the anterior and middle scalene muscles
how many divisions of the brachial plexus are there?
6
anterior divisions of brachial plexus =
posterior divisions of brachial plexus =
anterior divisions of BP = flexors
posterior divisions of BP= extensors
how many cords are there in the brachial plexus?
three
lateral
medial
posterior
study
what spinal cord levels make the cervical plexus?
C1-C4
study
cutaneous branches of the cervical plexus (4)
lesser occipital n.
great auricular n.
transverse cervical n.
supraclavicular n.
what is a plexus?
ventral rami joining and collectively innervating a region
brachial plexus - upper limbs
what froms a plexus?
ventral rami
red: sensory
purple: motor (diaphragm)
green: mostly motor
What’s the first muscle that you need to remove to see the cervical plexus?
platysma
as we descend the cervical region, do the ventral rami get bigger or smaller?
bigger
sensory branches = _____ to SCM
motor branches = _____to SCM
sensory = superficial to SCM
motor = deep to SCM
cutaneous branches of the cervical plexus
lesser occipital n
greater auricular n
transverse cervical n
supraclavicular n
what spinal level do the cutaneous branches belong to?
lesser occipital n
greater auricular n
transverse cervical n
supraclavicular n
lesser occipital n (C2)
greater auricular n (C2, C3)
transverse cervical n (C2, C3)
supraclavicular n (C3, C4)
greater occipital n =
lesser occipital n =
greater occipital n = dorsal rami
lesser occipital n = ventral rami
what levels do the greater, lesser, and least occipital nerves come from?
greater and lesser from C2
least from C3
what levels do the greater and lesser occipital nerves come from?
BOTH from C2
greater is a dorsal rami
lesser is ventral rami
motor nerves of the cervical plexus
- thyrohyoid
- geniohyoid
- ansa cervicalis
– superior and inferior roots - superior belly of omohyoid
- sternothyroid
- sternohyoid
- inferior belly of omohyoid
ansa cervicalis: superior root comes from level ___
C1
ansa cervicalis: inferior root comes from levels ___
C2 and C3
phrenic nerve comes from what levels
C3
C4
C5
what are the three nerves of the brachial plexus (that I need to know)?
medial
ulnar
radial
what do the brachial plexus nerves do?
medial: flex wrist, thumb, and digits (minus pinky)
*carpal tunnel
ulnar: flex pinky/ring finger and wrist
*funny bone
radial: extend arm, elbow, wrist
