spinal cord Flashcards
Where does the spinal cord arise cranially?
It arises cranially as a continuation of the brainstem at the medulla oblongata
Where does the spinal cord terminate?
L1/L2 vertebrae where it terminates as the conus medullary (medullary cone)
What anchors the spinal cord in place?
a thin thread called the filum terminale which extends from the tip of the conus medullaris to the first coccygeal vertebra
What does the medulla oblongata control?
autonomic functions
What does the medulla oblongata connect?
brain and spinal cord
What is the name of the collection of spinal nerve roots distal to the conus medullaris?
Cauda equina
What does the cauda equina consist of?
sacral and coccygeal spinal cord segments
What is the cauda equina vital for?
bladder control, urethral and anal sphincters and overall maintenance of continence
What is the filum terminale made up of?
made up of a delicate band of fibrous tissue
What is the spinal cord surrounded by?
spinal meninges containing cerebrospinal fluid
How many spinal nerves are there?
31 bilatterally paired spinal nerves
where is the cervical enlargement of the spinal cord?
located approximately at C4-T1 level
What does the cervical enlargement of the spinal cord represent?
The origin of the brachial plexus
Where is the lumbar enlargement of the spinal cord located?
between T11-L1 level
What does the lumbar enlargement of the spinal cord represent?
The origin of the lumbar and sacral plexi
What are spinal meninges?
a layered unit of membranous connective tissue that surrounds the spinal cord and cauda equina
What do spinal meninges provide?
protection
What are the 3 layers of meninges and where are they?
superficially starts with dura mater then the arachnoid mater and Pia mater is the deepest layer
Where does the dura mater extend from and go to?
extends from the foramen magnum to the filum terminale
What is the space between the vertebra and dura mater called?
epidural space
What does the epidural space contain?
the internal vertebral venous plexus
What happens with the dura mater as spinal nerves exit the vertebral canal?
They pierce the dura mater passing through the epidural space, the dura mater surrounds the nerve root and fuses with the outer connective tissue covering the nerve
What is the outer connective tissue covering the nerve called?
epineurium
What is the dura mater composed of?
tough and fibrous collagen fibres
What type of membrane is the arachnoid mater?
a delicate membrane
What separates the pia mater and arachnoid mater?
subarachnoid space
What does the subarachnoid space contain?
Cerebrospinal fluid
What does the subarachnoid space expand to form distal to the conus medullaris?
the lumbar cistern
Where is the lumbar cistern located?
between the end of the spinal cord and the end of the vertebral column
Describe the pia mater
thin membrane that covers the spinal cord, nerve root and their blood vessels
Inferiorly what does the pia mater fuse with?
filum terminale
What does the pia mater do between the nerve roots?
thickens to form the denticulate ligaments
What do the denticulate ligaments attach to?
dura mater
What do the denticulate ligaments prevent?
lateral movement
What divides the spinal cord into two symmetrical halves?
dorsal median sulcus and ventral median fissure
What do afferent spinal nerves enter the cord via?
dorsal/posterior root