The Spinal Cord and Spinal Nerves Flashcards
What are spinal meninges?
connective tissue layers that provide protection and oxygen and nutrients to the spinal cord.
- duramater
- arachnid
- piamater
Cerebrospinal Fluid (CSF)
the space between the spinal cord with chemical protection
- provides the spinal cord with chemical protection
- physical protection
conus medallaris
- the caudal end of the spinal cord
- causa equina
How many parts is the spinal cord divided into?
1) gray matter
2) white matter
Gray matter of spinal cord
composed of neuron cell bodies
1) dorsal gray: cell bodies of sensory neurons receive and sum signals from PNS sensory neurons
2) ventral: cell bodies of motor neurons receive and sum signals from PNS sensory neurons
White matter of spinal cord
contains ascending and descending fiber pathways
Ascending pathways of the spinal cord
relay sensory info from spinal cord to brain
descending pathways of the spinal cord
relay motor commands from the brain to the spinal cord
Dorsal Root
- cell bodies are in dorsal root ganglion
- carry SENSORY info from PERIPHERAL RECEPTORS to the SPINAL CORD
Ventral Root
- cell bodies are in the spinal cord
- carry MOTOR info from the SPINAL CORD to MUSCLES
Lesion of spinal nerve
both sensory and motor nerves affected
loss of sensation and muscle paralysis
- diabetes
- alcoholism
- some infections
lesion of dorsal root
sensory axons affected
pain tingling or numbness
- injury
- herpes zoster virus
Lesion of ventral root
motor axons affected
-muscle paralysis
Intercostal nerves
nerves that travel between ribs
Spinal Nerve plexus
spinal nerve above and below the ribs from plexuses
What things to the intercostal nerves innervate?
muscles of the trunk
and the skin go the trunk
what things do the spinal nerves plexuses innervate?
the muscles of the neck and the skin of the neck and limbs
musculocutaneous nerve
motor innervation-all muscles of all anterior flexor arm
sensory innervation-skin of anterior forearm
Median nerve
motor innervation-most muscles anterior fore arm
sensory- skin of hand
ulnar nerve
motor-muscles of hand
sensory-skin of hand
radial nerve
motor-all muscles of posterior arm and forearm
sensory- skin of posterior arm, forearm, and hand
axillary nerve
motor- muscles of shoulder
sensory- skin of shoulder
femoral plexus
lower limbs
femoral nerve
motor-muscles of anterior thigh
sensory-skin of anterior thigh
sciatic nerve
motor-muscles of posterior thigh all leg foot
sensory- posterior thigh all leg and foot
the sciatic nerve turns into which two nerves
tibial and fibular
obturator
motor-muscles of medial thigh
sensory-skin of medial thigh
