Spinal Cord Flashcards
What is the Conus Medullaris?
Where the spinal cord terminates at the level of L1 vertebrae
What is the cervical enlargement? Where is it?
C4-T1, related to brachial plexus (bundle of nerves that innervate the upper limb)
What is the lumbrosacral enlargement? Where is it?
T11-S1, related to the lumbar and sacral plexuses (nerve plexuses that innervate the abdominal wall and lower limb)
What are meninges?
membranes that surround the spinal cord and nerve roots- contains Cerebrospinal fluid
What is the Dura Mater?
Outer most meningeal layer. Tough outer layer, Forms the Dural Sac
What does the Dura Mater do?
Encloses the spinal cord, extends along nerve roots to the intervertebral foramina
Where does the dura mater start/stop?
Forms Dural Sac that begins at foramen magnum of skull, ends at level of S2
What is the arachnoid mater?
A delicate middle meningeal layer,
How is the arachnoid mater attached to underlying membranes?
Arachnoid trabeculae (strands of connective tissue)
What is the pia mater?
Thin layer that adheres directly to the surface of the spinal cord
How does the pia mater attach to the dura mater? What does this do?
Attaches by Denticulate Ligaments (transverse extensions of pia mater). Suspends the spinal cord within the dural sac
What is the Filum Terminale? What does it do?
Thin cord of pia mater that extends from conus medullaris to apex of the dural sac. Surrounded by spinal dura mater, and extends to the end of the vertebral canal to anchor both membranes to the coccyx.
What is the epidural space? What is contained here?
Space between bony wall of vertebral canal and dura mater
Contains fat and vertebral venous plexus
What is the subdural space? What is contained here?
A POTENTIAL space between dura and arachnoid layers.
Contains thin film of lubricating fluid
What is the subarachnoid space?
Deep to arachnoid layer- Contains cerebrospinal fluid
What is the lumbar cistern?
Enlargement of the subarachnoid space within the dural sac (inferior to conus medullaris)
How many pairs of spinal nerves are there?
31 total 8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccygeal
Anterior ROOT contains ______ fibers?
Motor (efferent)
Posterior ROOT contain _______ fibers?
Sensory (afferent)
Every spinal nerve divides into ______ and ______ ramus?
Posterior/Anterior
What do anterior rami innervate?
Anterolateral trunk wall and the limbs
What do posterior rami innervate?
The skin and muscles of the back and posterior scalp.
Where does a spinal nerve exit the spinal cord?
Intervertebral foramina
Where do cervical neres C1-C7 exit?
Superior to the vertebra of the same number
Where does C8 spinal nerve exit?
Inferior to C7 vertebrae, superior to T1 vertebrae
Where do spinal nerves T1-Co1 exit?
Canal inferior to the corresponding vertebrae
What is the cauda equina?
Loose group of nerve roots that descend below the conus medullaris within the lumbar cistern in order to exit at the appropriate level
What do anterior rami of the thoracic spinal nerves become?
Intercostal nerves- run in the spaces between the ribs in thoracic wall
What plexus does the anterior rami of C1-C4 form?
Cervical plexus
What plexus do the anterior rami of C5-T1 form?
Brachial plexus
What plexus does the anterior rami of L1-L4 form?
Lumbar plexus
What plexus does the anterior rami of L4-S3 form?
Sacral plexus
The spinal cord terminates where?
At the L1 Vertebrae, terminates as the Conus Medullaris
