Lecture 3 - Spinal Cord & Meninges

What kind of information do Spinal Nerves carry

Motor and Sensory

How many layers of meninges is the spinal cord surrounded by

3

At which vertebra does the Spinal Cord end

L2 - Medullary cone

True or false: nerve roots still travel after the spinal cord ends

True

What is the Cauda Equina

Bundle of Nerve roots

What holds the Cauda Equina

Dural Sac

Where does the Dural Sac extend into

The proximal sacrum S2

What is labelled in this photo

Medullary cone, Terminal filament, Cauda Equina

What is the terminal filament

Anchors the coccyx and gives spinal cord stability

What is labelled in this structure

Intervertebral Foramen

What are Intervertebral Foramen

Routes through which spinal nerves exit the vertebral canal

What is the spinal cord inside

Vertebral foramina / vertebral canal

Order of structures associated with spinal nerve starting with Rootlets

Rootlets, Roots, Spinal Nerve, Rami

What does the Spinal Nerve divide into

Anterior and Posterior Rami

What information do the Anterior and Posterior Rami carry

Sensory and motor information to the rest of the body

Motor information goes TOWARDS or AWAY from the spinal cord

Away

Sensory information goes TOWARDS or AWAY from the spinal cord

Towards

Motor information and sensory information which ROOT in order

Anterior and posterior

Steps for Motor information from spinal cord

Spinal cord, anterior rootlets, anterior root, spinal nerve, rami

Steps for Sensory information towards spinal cord

Periphery, rami, spinal nerve, posterior root, posterior rootlets, spinal cord

What fibres do the anterior roots/rootlets contain

Efferent/motor fibres to skeletal muscle

What fibres do the posterior roots/rootlets contain

Afferent/sensory fibres to from skin, deep tissues, etc

Do Spinal Nerves carry sensory or motor fibres or both

Both

Do Rami carry sensory or motor fibres or both

Both

What do posterior rami innervate

Deep back muscles, carrying sensory information from overlying skin

What do anterior rami innervate

Muscles (upper limb, intercostal muscles), carry sensory information from overlying skin

Meningeal layers surrounding spinal cord order from superficial to deep

Dura Mater, Arachnoid Mater, Pia Mater

What is the Denticulate Ligament derived from

Pia Mater

What is Arachnoid Mater pressed up against and why

Pressed up against Dura by cerebral spinal fluid

What is the epidural space

Between vertebral canal and dura mater

What is subarachnoid space

Space between arachnoid and pia

Epidural Anesthesia - Epidural space

No meningial layers pierced

Lumbar Spinal Puncture to obtain CSF - Subarachnoid space

Dura and arachnoid mater will be pierced

What does the Sacral Hiatus reflect

Absence of laminae and spinous processes of S4 and S5 vertebrae

What do the Sacral Cornua represent

Inferior Articular Process of S5 vertebra