Spinal Cord

Question 1

What does the spinal Cord begin as?

Answer 1

-Begins as the continuation of medulla oblongata.

Question 2

What does the spinal cord develop from ?

Answer 2

Spinal cord develops from the caudal part of the neural tube

Question 3

What are the two enlargements of the spinal cord ?

Answer 3

• Cervical enlargement (C4-T2 spinal segment)
• Lumbar enlargement (L1-S3 spinal segment)

Question 4

What do the two enlargements support?

Answer 4

-Cervical enlargement is for the supply of upper limb muscles
-Lumbar enlargement is for the supply of lower limb muscles.

Question 5

What are the coverings of the spinal cord ?

Answer 5

From outside to inside
- Spinal dura mater
- Arachnoid mater
- Piamater

Question 6

2 layers of cranial dura matter ?

Answer 6

An outer endosteal layer and an inner meningeal layer.

Question 7

Nerve Supply of dura matter ?

Answer 7

recurrent meningeal branches of the spinal nerves.

Question 8

What are the indication for a lumbar puncture ?

Answer 8

Collection of cerebrospinal fluid (in a case of suspected meningitis)

Question 9

What are the risks of a lumbar puncture ?

Answer 9

-Damage to the spinal nerve roots resulting in weakness or loss of sensation, or even paraplegia.
-epidural infection is present or suspected, pose a risk of infection at the puncture site.

Question 10

Where is the pia matter modified?

Answer 10

-Filum terminale: Continuation of pia mater beyond the conus medullaris.
-Linea splendens – a white, glistening ,thickened band of pia mater in the anterior median fissure of the spinal cord.
-Sub-arachnoid septum: an incomplete septum on the dorsal surface of spinal cord.

Question 11

What is the Ligamenta denticulata ?

Answer 11

Two ribbon like lateral extensions of pia mater from the sides of spinal cord between the ventral and dorsal nerve roots.

Question 12

Clinical Significance of Ligamenta denticulata ?

Answer 12

• last tooth (21st) of ligamentum denticulatum extends obliquely between T12 and L1 spinal nerves which helps the surgeon in locating the first lumbar nerve during operation.
  -Often utilized by neurosurgeons during selective tractotomy operation

Question 13

What are surface features of the spinal cord?

Answer 13

-An anterior median fissure on the ventral surface.
-A shallow posterior median sulcus on the dorsal surface.
-A posterolateral sulcus

Question 14

What are the 31 pairs of spinal nerve?

Answer 14

Cervical - 8, Thoracic - 12, Lumbar - 5, Sacral - 5 and Coccygeal – 1