Vertebral Canal & Its Contents

To what vertebrae does the spinal cord extend?

~L2

Name of collection of elongated lumbar and sacral/coccygeal nerve roots

Cauda equina

Surrounds spinal cord from base of skull to S2

Dural sac

Tapered terminal portion of spinal cord

Conus medullaris

Conus medullaris vertebral level

L1~L2

Vestigial remnant of caudal spinal cord

Filum terminale

Extends from medullary cone to tip of dural sac

Internal filum terminale

Extends from tip of dural sac to sacrum/coccyx

External filum terminale

Helps anchor spinal cord inferiorly

External filum terminale

Spinal cord enlargements

Cervical and lumbosacral

Lateral extension of the dural mater into each intervertebral foramina and the dorsal and ventral roots of spinal nerves

Dural sleeve

Membrane that lines the inside of the dura and dural sleeves

Arachnoid mater

Where is CSF located?

Subarachnoid space

Innermost membrane that adheres to surface of spinal cord

Pia mater

Lateral extension of pia mater between dorsal and ventral roots which help to anchor cord laterally

Denticulate ligaments

Epidural space contents

Adipose tissue and internal venous plexus

Blood supply to the spinal cord is derived from ______ and ______ components

Longitudinal and segmental

Which arteries vascularize the superior portion of the spinal cord?

Longitudinal

Longitudinal arteries include

Anterior spinal artery and paired posterior spinal arteries

Irregularly spaced vessels that enter the vertebral canal through the intervertebral foramina and provide additional blood supply to the spinal cord

Segmental medullary arteries

Largest of the segmental vessels that reinforces circulation to the interior 2/3rds spinal cord

Artery of Adamkiewicz

Small vessels that vascularize the dorsal and ventral roots but do not reach the spinal arteries

Radicular arteries

Where venous blood from the spinal cord drains

Anterior and posterior spinal veins

Spinal veins drain into the

Internal/epidural venous plexus

The internal venous plexus connects with the ______ via the ______ (which drain the vertebrae)

External venous plexus, basivertebral veins

The interconnecting vertebral venous plexuses (VVP)

Batson’s plexus

Where are the veins that Batson’s plexus has direct venous connections with?

Pelvis, posterior thoracic wall, cranial cavity

Ideal access site for spinal tap

L3-L5

What all do you hit otw when performing a spinal tap?

supraspinous, interspinous, ligamentum flava, dura, arachnoid, subarachnoid space

Which direction does the protrusion of the nucleus pulposus typically occur?

Posterolaterally

When a herniated disc occurs, which nerve gets compressed?

Lower

95% of lumbar disc herniations occur where?

L4/L5 or L5/S1

Vertebral arteries give rise to the

Longitudinal arteries