Ch 7 - SCI: Epidemiology and Anatomy Flashcards
What is the incidence of SCI in the US?
40 new injuries per million population/year = 12,000 new SCI cases/year
What is the prevelance of SCI in the US?
Approximately 273,000 cases
What is the average age of injury of SCI?
42.6 years of age
What is the MCC of SCI in elderly?
Falls followed by MVC
What are the MC times for SCI?
– Summer season (highest incidence in July)
– Weekends (Saturday > Sunday)
– Nighttime
What is the MC level of spinal cord injury?
C5
What is the MC level of injury of paraplgeia?
T12
What is the MC type of SCI?
Incomplete tetraplegia
Describe association with marriage and SCI.
MC to be single
Likelihood of marriage after SCI is reduced
Post-injury marriages survive better than pre-injury marriages
Describe association with return to work after SCI.
1 year post-injury 11.8% employed
20 years post injury 35% employed
What is the leading cause of death for chronic SCI?
Respiratory d/o
Pneumonia MCC
What are secondary causes of death in chronic SCI?
- Heart disease
- Septicemia from pressure ulcers, UTI or respiratory infection
- Cancer
What is the relationship between SCI and suicide?
2nd MCC of death in <25 yo
MC in paraplegia than tetraplegia
Where does the conus medullaris become the cauda equina?
L1-2
What is the location of the Fasiculus gracilis?
Medial dorsal columns
Proprioception from the leg
What is the function of the Fasiculus gracilis?
Light touch and vibration
What is the location of the Fasiculus cuneatus?
Lateral dorsal columns
Proprioception from the arm
What is the function of the Fasiculus cuneatus?
Light touch and vibration
What is the location of the Spinocerebellar tract?
Superficial lateral column
What is the function of the Spinocerebellar tract?
Muscular position and tone, unconscious proprioception
What is the location of the Lateral spinothalamic tract?
Ventrolateral column
What is the function of the Lateral spinothalamic tract?
Pain and thermal sensation
What is the location of the Ventral spinothalamic tract?
ventral column
What is the function of the Ventral spinothalamic tract?
Tactile sensation of crude touch and pressure
What is the location of the Lateral corticospinal tract?
Deep lateral column
What is the function of the Lateral corticospinal tract?
Motor: Theorized to have motor fibers running, medial (cervical)→ lateral (sacral) C → S (motor neuron distribution)
What is the location of the Anterior corticospinal tract?
Medial ventral column
What is the function of the Anterior corticospinal tract?
Motor: Neck and trunk movements
Where do the Lateral corticospinal tracts cross?
80% to 90% of the axons cross over (decussate) to the contralateral side at the pyramidal decussation in the medulla
What is the function of the spinocerebellar tracts?
Transmit unconscious proprioception from the ipsilateral side of the body and do not cross
Where do Lateral spinothalamic tracts cross and run?
Fibers cross over to the opposite half of the cord within 1 to 3 vertebral segments, ascend in the lateral spinothalamic tracts to the thalamus on the opposite side and then ascend in the internal capsule to the postcentral gyrus of the cerebral cortex
Where do the Dorsal columns cross and run?
Sensory fibers synapse at DRG and immediately ascend in to the ipsilateral dorsal white columns, travel up to the medulla, and decussated
What is the blood supply of the spinal cord?
1 anterior spinal artery: supplies anterior 2/3
2 posterior spinal arteries supply posterior 1/3 of the cord
What is the artery of Adamkiewicz?
Arises from the left intercostal or lumbar artery at the levels of T9–L3 and provides the major blood supply to the lower 2/3 of the lumbosacral spinal cord
What is the watershed area of the spinal cord?
Fewer radicular arteries that supply T4–T6 and prone to ischemia during clamping of the aorta during surgery
