Spinal Cord Quick Hits Flashcards
Where does the Artery of Adam usually arise from?
Left side, T8-T12
What is the artery of Adam? What does the Artery of Adam supply?
Most important radicular artery
Anterior Spinal artery which serves the anterior two thirds of the spinal cord
What is preserved of there is damage to the artery of adam?
Touch and proprioception which is controlled by the dorsal column
What are the two sources of blood for the spinal cord?
Spinal arteries: 2 posterior and 1 anterior (These run along the entire spinal cord)
Radicular arteries: 6-8 (Does not run the entire length)
What areas does the posterior spinal artery perfuse?
Posterior 1/3 of the spinal cord \
What areas does the anterior spinal artery perfuse?
Anterior 2/3 of the spinal cord
What is Beck’s triad?
Flaccid paralysis of the lower extremities
Bowel and bladder dysfunction
Preserved touch and proprioception
What three spinal pathways are supplied by the anterior spinal artery?
Corticospinal tract
Autonomic motor fibers
Spinothalamic tract
What is one spinal tract supplied by the posterior spinal artery?
Dorsal column
What are laminae 1-6?
Dorsal gray matter - Sensory
What are laminae 7-9?
Ventral gray matter - Motor
What is the tract of Lissauer?
Pain and temperature
What is the lateral spinothalamic tract?
Pain and temperature
What is the ventral spinothalamic tract?
Crude touch and pressure
What is the dorsal column control?
Fine touch and proprioception
What is the lateral corticospinal tract?
Limb motor
What is the ventral corticospinal tract?
Posture motor
What are the corticospinal tracts?
Travel from cortex to spine
Motor pathways
What are the spinothalamic tracts?
Spine to thalamus
Sensory pathways
Proprioperception is controlled by?
Ruffini’s endings
Two point discrimination is controlled by?
Meissner’s corpuscles
Continuous touch is controlled by?
Merkel’s discs
Vibration is controlled by ?
Pacinian corpuscles
Which pathway transmits afferent nociceptive input to the brain?
Anterolateral system
Which column has large myelinated fibers?
Dorsal
Which column transmits vibration?
Dorsal
Which column has small unmyelinated fibers and transmits pain?
anterolateral system
Which column transmits vibration, pressure and proprioception?
Dorsal
Which column has two point discrimination and rapid conducting fiebrs?
Dorsal
Which column transmits sex and temperature
anterolateral
What are two types of 1st order neurons within the anterolateral system?
A delta fibers
and
C fibers
Where do nociceptive neurons primarily synapse with second order neurons?
Substantia gelatinosa of the dorsal horn
Where do second order neurons synapse with third order in the anterolateral system?
Reticular activating system and thalamus
What does the corticospinal tract carry?
Motor signals from the cerebral cortex to the muscles of the body
What is seen when an injury is above decussation?
Spastic paralysis on the contralateral side
What is seen when an injury is below decussation?
Flaccid paralysis on the ipsilateral side
What do SSEP’s monitor?
Sensory and integrity of the dorsal column
What do MEP’s monitor?
integrity of the corticospinal tract (Motor)
Anterior spinal artery perfuses this region of the cord
What does the Babinski test assess? What is considered a positive test?
Integrity of the corticospinal tract
An upward extension of the big toe - indicates an injury
Where does the upper motor neuron begin and end?
Begins in the cortex and ends in the ventral horn of the spinal cord
Where does the lower motor neuron begin and end?
Begins in the ventral horn and ends at the neuromuscular junction
What neuro drug can cause thrombocytopenia?
Valproic Acid
What neuro drug may cause aplastic anemia?
Phenytoin
What is the order of flow of CSF?
- Lateral ventricles
- Foramen of Monro
- Aqueduct of Sylvius
- Foramen Magendie
What forms the grey matter?
Cell bodies
What forms the white matter?
Axons
What neuron is the most abundant in the CNS?
Multipolar
What neuron is located in the dorsal root ganglion and cranial ganglion?
Pseudounipolar
What neuron is located in the retina and ear?
Bipolar
Critical thresholds of CBF?
CBF 20mL - evidence of ischemia
CBF 15mL - complete cortical suppression
CBF <15mL -cell death
5 determinants of CBF?
CMRO2
Venous pressure
PaCO2
PaO2
CPP
What is normal CMRO2?
3mL/O2/100g brain tissue
What temp does EEG suppression occur?
18-20 degrees C
4 ways that impair venous drainage?
Vena cava syndrome
Vena cave thrombosis
Increased intrathoracic pressure
Jugular compression
A fixed and dilated pupil suggests herniation of what?
Temporal uncus
CN3
What drugs reduce CSF production?
Acetazolamide and lasix
What artery does not have a pair?
Basilar
Most important risk factor for a stroke?
HTN
others
smoking
diabetes
HLD
alcohol
Elevated homocysteine
First line treatment for acute ischemic stroke?
Aspirin
When should an embolectomy be performed?
Within 6 hours
What should intraop BP be between for aneurysm ?
120-150
What is cerebral salt wasting syndrome?
Patients who suffer a subarachnoid hemorrhage
Hyponatremia from the release of natriuretic peptide
Treat with isotonic fluids
What should CPP be held at with TBI? What fluids should be used
> 70
Hypertonic
