spinal cord tracts and reflexes Flashcards
(19 cards)
function of spinal cord white matter
Contains bundles of myelinated axons called tracts or fasciculi
Axons ascend or descend in the spinal cord within the white matter to transmit signals between the CNS and periphery.
surrounds the grey matter peripherally
function of spinal cord grey matter
Contains cell bodies, dendrites, and proximal axons of neurons
central, butterfly shape
function of the spinothalamic tract
Pressure sensation (anterior)
Protopathic sensation
Temperature (lateral)
Pain (lateral)
Crude touch (anterior)
dorsal column
Proprioception
Epicritic sensation: fine touch, vibration, pressure sensation
pacinian corpuscles detect
vibration
meissner’s corpuscles detect
touch
muscle spindles detect
proprioception
what two tracts govern conscious sensation
spinothalamic tract
dorsal column
what two tracts govern unconscious sensation
spinocerebellar tract
spinoolivary tract
name two descending motor tracts
corticospinal tract
extrapyramidal tracts
central cord syndrome is affecting
Bilateral central corticospinal tracts and lateral spinothalamic tracts
clinical features of central cord syndrome
Bilateral paresis: upper > lower extremities
anterior cord syndrome is affecting
Corticospinal tracts and spinothalamic tracts
clinical features of anterior cord syndrome
Bilateral motor paralysis, loss of pain and temperature sensation, and autonomic dysfunction below the level of the lesion
posterior cord syndrome is affecting
Posterior columns
clinical features of posterior cord syndrome
Bilateral loss of proprioception, vibration, and touch sensation below the level of the lesion
brown sequared syndrome causes
hemisection syndrome
Ipsilateral
Loss of proprioception, vibration, and tactile discrimination below the level of the lesion
Segmental flaccid paresis at the level of the lesion
Spastic paresis below the level of the lesion and Babinski sign
Horner syndrome in lesions above T1
Contralateral: loss of pain and temperature sensation one or two levels below the lesion
conus medullaris syndrome
Sudden, bilateral
Symmetrical, flaccid muscle weakness of lower limbs, possibly fasciculations
Lower back pain
Hyperreflexia
Absence of Achilles reflex
Symmetrical, bilateral perianal numbness
Sensory dissociation
Bladder and fecal incontinence
cauda equina syndrome
Unilateral, asymmetrical
LMN damage: flaccid muscle weakness and muscle atrophy of the leg
Severe radicular pain
Hyporeflexia
Absent knee jerk reflex and ankle jerk reflex
Saddle anesthesia
Loss of anal and bladder sphincter control
