Spinal cord and Nerves Flashcards
What are Features of the Spinal Cord?
Cervical enlargement
Lumbosacral enlargement
Conus medullaris
Cauda equina
Filum terminale (Anchors spinal cord)
Posterior and Anterior Median sulci and fissure
Describe the parts of the spinal cord from a transverse view?
White matter (Outsides)
Gray matter (Inside)
Central canal
Dorsal root is sensory
Ventral root is motor
Roots merge to form a spinal nerve
What are the three spinal meninges?
Dura mater (Tough, fibrous outermost layer)
Arachnoid mater (Middle layer)
Pia mater (Innermost layer)
How many pairs of spinal nerves are there?
There are 31 pairs of spinal nerves
How many of each type of spinal nerves are there?
8 Cervical nerves
12 Thoracic nerves
5 Lumbar nerves
5 Sacral nerves
1 Coccygeal
What are the linings of a peripheral nerve?
Epineurium - Outerlayer (becomes continuous with dura mater
Perineurium - layer surrounding a fascicle (fascicle is a bundle of axons)
Endoneurium - layer surrounding a single axon
What are the four nerve plexuses
Cervical plexus
Brachial plexus
Lumbar plexus
Sacral plexus
What are key features of the Cervical Plexus?
Consists of cutaneous and muscular branches
Largest nerve is the phrenic nerve
What are key features of the Brachial Plexus?
The largest nerves are the ulnar and radial nerve
What are key features of the Lumbar and sacral plexus? (Aka Lumbosacral plexus)
The main lumbar plexus nerve is the Femoral nerve
The main sacral nerve is the Sciatic nerve
Where do cervical plexus nerves emerge from?
C1-C5
Where do brachial plexus nerves emerge from?
C5-T1
Where do lumbar plexus nerves emerge from?
T12-L4
Where do sacral plexus nerves emerge from?
L4-S4
What is a reflex?
An immediate involuntary response
