L 13 & 14 - Spinal Cord Flashcards
Posterior cord syndrome
Corticospinal tract
Motor tract (down):
Cortex - contralateral
Midbrain - cerebral peduncle
*Medulla - pyramidal decussation (cross) to pyr. tract
Spine - corticospinal to ventral root (ipsalateral)
Touch and pressure neuro pathways
Sensory tract (up):
Spine - ipsalateral dorsal columns (1 of 2)
*Medulla (cross to medial leminiscus)
Cortex - synapse in thalamus
Propreoception neuro pathways
Sensory tract (up):
Spine - dorsal columns (ipsalateral)
to Cerebellum (through spinocerebellar tract)
*Medulla (cross to medial leminiscus)
Cortex - synapse at thalamus
Nociception and temperature neuro pathways
Sensory tract (up):
*Spine - cross dorsal horn to spinothalamic tract !every level
Medulla + Pons (synapse at reticular formation)
Midbrain - periaqueductal grey matter
Cortex - synapse at thalamus
white matter label
- fasciculus gracilis
- fascisulus cuneatus
- corticospinal tract
- lateral spinothalamic
- medial leminiscus
what does it when when a neural pathway crosses
‘changes’ sides of the body, injuries above cross will be contralateral, below cross will be ipsalateral
intervertebral discs are composed of
annulus fibrosis (outer), nucleus pulposus (inner)
upper vs lower motor neurons location
upper - in spinal cord and brain
lower - outside spinal cord
types of paralysis
spastic - tense muscle - UMN
flaccid - relaxed muscle - LMN
signs of motor neuron lesions
weakness - U and L
atrophy - L
reflexes and muscle tone - increased for U, decreased for L
fasciculations (small muscle twitch) - L
clonus (large muscle twitch) - U
babinski sign (+ toes up, - toes down) - U
Paresis
muscle weakness caused by lesion in a plexus, innervation not fully lost