hole in the bottom of the scull

where spinal cord begins

continous with the medulla oblongota

C3-T2 (says google)

gives rise to the brachial plexus

innervates upper limbs

aka lumbar enlargement

L1-S3

gives rise to lumbar and sacral plexuses

innervates lower limbs

termination of the spinal cord in a cone shape

around L1/L2 in an adult

aka filum terminale

derived from the pia mater

connective tissue filament

connects conus medullaris to coccyx

upper portion is in the dural sac

week 8: cord and vertebre are the same length

month 3: vertebral column begins to grow faster than the cord leaving the end of the cord higher in the canal and elongating nerve roots

month 6: the end of the cord is around S1

at birth: the end of the cord is around L3

adult: the end of the cord is around L1/L2

central tube of the vertebre

remnemt of the lumen of the neural tube

communicates with the 4th ventricle of the brain

lined by ependymal cells like all ventricles

notch in the posterior vertebre between the posterolaterall sulcus and posterior median sulcus

is only present in the cervical and upper thorasic vertebre

aka dorsal root

carries information to the spinal cord

afferent sensory fibers

contains cell bodies of sensory neurons

aka posteior root ganglion

carries info away from the spinal cord

efferent motor fibers

outside layer of the vertebre

has ascending and descending fibers or tracts

contains anterior spinal vessels

deep groove almost to central canal

gray matter

sensory functions

influenced by information sent via posterior root

many neurons have axons extending into the white matter

grey matter

interomedial lateral nucleus

only in T1-L2

preganglionic sympathetic neuron location

gray matter

interneurons for segmental and intersegmental integration

grey matter

voluntary movements

neuron axons leave through anterior roots to supply skeletal muscle (somatic motor neurons)

horn is large in the cervical and lumbosacral enlargements where neurons for limbs are

formed by ventral and dorsal roots

mixed nerve

after exiting the vertebral column it splits into the posterior and anterior ramus

31 pairs

has both sensory and motor fibers

ex: spinal nerves

division of a spinal nerve after the vertebral canal

smaller

innervates skin and deep back muscles

division of a spinal nerve after the vertebral canal

larger

innervates skin and muscles of the limbs, and anterolateral trunk, and superficial back muscles

31 total

8 cervical

12 thorasic

5 lumbar

5 sacral

1 coccygeal

cutaneous sensory neuron that innervates areas of the skin that can be traced back to a specific spinal nerve

cutaneous nerves usually have sensory fibers from more than one spinal nerve

the limbs have a strange distribution pattern due to their development

helps map sensory deficit to a spinal nerve issue

coverings of the spinal cord

connective tissue

epidural space

dura mater

subdural space

arachnoid

subarachnoid space

pia mater

outermost, strong, fibrous, forms loose sac

terminates at S2

continous with brain dura

is picked up by filum terminale as it leaves sac

forms a sleeve around spinal nerves under they leave the intervetebral foramen then it fuses with the epinerum

connective tissue covering of a nerve

fuses with dura mater at interveterbal foramen

middle layer

continous with the cranial arachnoid

extends length of the dural sac

lines dural sleeves

filled with CSF

continous with the subarachnoid space around the brain

extends to S2 and nerve root sleeves

area for spinal tap

aka lumbar puncture

usually done in the lumbar cistern

done in the subarachnoid space at L3/4 or L4/5

space in the dural sac where the conus medullaris ends and the cauda equina begins

area where a lumbar puncture in the subarachonid space occurs

continous with pia mater of the medulla oblongata

derives the filum terminale

contains denticulate ligament

in the pia mater

extension of pia mater in the coronal plane

stabilizes the spinal cord

at lateral edge of the cord between anterior and posterior roots

extends across subarachnoid space attaching to the dura mater by 20-21 denticulation projections