Spinal Cord Flashcards
Superior boundary of spinal cord
Foramen Magnum
Superior most ventral rootlet of C1
Inferior boundary of spinal cord
Disc between L1 and L2
Cervical nerves are named for
Bone below
C8 exits at
IVF between C7 and T1
C1 exits between
Occipital and atlas
Thoracic nerves are named for
Bone above
T12 exits at
T12 and L1
S1 though S4 nerves exit
Dorsal and ventral sacral foramina
S5 exits at
Sacral hiatus
Co1 exits at
Sacral hiatus
Co1 cord level is found where in adulthood
L1 and L2 Disc
Conus medullaris
Roots of lumbar, sacral, and coccygeal nerves run below cord down
Lumbar cistern
Cauda equina
Lateral horn location
T1-L2/L3
S2-S4
Dorsal horn
Sensory reception
Lateral horn
Cell bodies of preganglionic autonomic neurons
Anterior horn
Motor function
Funiculi
Column of white matter (no specific function)
Carry info both up and down cord
Fasciculi
White matter tract with specific function
NCAM’s (nerve cell adhesion molecules)
Surface proteins that help fasciculi fibers associate with each other during development
Function of gracilis and cuneatus
Two point touch discrimination
Vibratory sensation
Kinesthetic sensation
Lateral spinothalamic tract carries
Pain/temperature
Anterior spinothalamic tract carries
Light touch/ pressure
Fibers of the spinothalamic tracts terminate in
VPL of the thalamus
Anterior spinocerebellar tract carries
Gross movements of lower body
Posterior spinocerebellar tract carries
Fine movements
Anterior corticospinal tract influences
Axial musculature of neck and shoulders
Lateral corticospinal tract function
Initiating and accomplishing precise skilled voluntary muscle movements
Corticospinal fibers synapse with neurons in ___, which then synapse in ___
Lamina VII
Lamina IX
____ cells from precentral gyrus of frontal lobe synapse directly on lamina IX
Giant pyramidal (Betz) cells
Lower motor neurons
Originate in spinal cord or brain stem and extend fibers to PNS to innervate somatic muscles
Upper motor neurons
Neurons from higher brain centers that influence LMN
UMN Lesions
Reduction or absence in voluntary movement
Hyperreflexia
Increase muscle tone
LMN lesions
Reduction or absence of voluntary movement
Hyporeflexia
Decreased muscle tone and atrophy
Pyramidal Neurons
UMN involved with initiation of skilled voluntary movements
Extrapyramidal neurons
UMN that originate in brain stem and extend down cord
Subconsciously influence posture, muscle tone, enhance reflexes
3 example of Extrapyramidal fibers in tracts
- Tectospinal tract
- Rubrospinal tract
- Vestibulospinal tract
Origin of tectospinal tract
Superior colliculus of tectum
Tectospinal tract fibers terminate in
C4-C5
Function of tectospinal tract
XI cranial nerve
Trapezius
Sternocleidomastoid