Somatic Innervation Flashcards
How many spinal nerves are there ?
31 pairs
What are the sections of spinal nerves and vertebrae?
Cervical – 8/7
Thoracic – 12
Lumbar – 5
Sacral – 5
Coccygeal – 1
Where do nerves exit?
cervical nerves = above vertebrae
C8 = above T1
all others = below vertebrae
What is the flow from the spinal cord to the spinal nerve?
spinal cord – dorsal rootlets (sensory) – dorsal root – spinal nerve
spinal cord – ventral rootlets (motor) – ventral root – spinal nerve
What are the divisions from the spinal nerve?
dorsal ramus (mixed)
ventral ramus (mixed)
What is the partial and full loss of sensory and motor functions?
Sensory = parestheia and numb
Motor = paresis and paralysis
What are dermatomes?
area of skin innervated by single spinal nerve
– diagnosing spinal injuries/shingles
What is the brachial plexus?
- nerves supply upper limb
- ventral rami
- mixed terminal branches
What is the organization of the brachial plexus?
roots, trunks, divisions, cords, terminal branches
What are the roots of the brachial plexus?
C5, C6, C7, C8, T1
What are the trunks of the brachial plexus?
superior
middle
inferior
What are the divisions of the brachial plexus?
anterior vs posterior
What are the cords of the brachial plexus?
lateral
posterior
medial
What are the roots and movements of the musculocutaneous nerve?
C5, C6, C7
arm flexors
What are the roots and movements of the axillary nerve?
C5, C6
shoulder
