Spinal Anatomy

Question 1

Damage to this can cause cauda equina syndrome, and which local anesthetics is avoided bc of this?

Answer 1

Conus medullaris; Lidocaine and Mepivacaine

Question 2

Spinal space is also known as

Answer 2

Intrathecal space or the subarachnoid space

Question 3

Where do spinals work?

Answer 3

They work on the spinal nerve roots as they exit the spinal cord.

Question 4

Where does the epidural space start (and end), and what does it contain?

Answer 4

Starts at the FORAMEN MAGNUM to the sacrococcygeal ligament. Contains vasculature, nerves, fat, lymphatic tissue.

Question 5

What is the depth of skin to ligamentum flavum in the lumbar area?

Answer 5

4 - 6 cm

Question 6

What is the avg thickness of the ligamentum flavum at L2?

Answer 6

5 - 6 mm

Question 7

What is the skin to ligamentum flavum in the thoracic area?

Answer 7

4.5 - 7.5 cm

Question 8

What is the width of the epidural space at C1? At T6?

Answer 8

As a result of cervical cord expansion, at C5 it is 1 - 1.5 mm and at T6 it is 2.5 - 3 mm.

Question 9

What are the four types of spinal nerve fibers?

Answer 9

Remember
A(s)SS E(m)SS your or after a block

Afferent (sensory)
Somatic
Sympathetic

Efferent (motor)
Somatic
Sympathetic

Question 10

What are the tissue layers from skin to spinal cord?

Answer 10

Skin
Subcutaneous tissue
Supra spinous ligament
Inter spinous ligament
Ligamentum flavum
Epidural space 
Dura mater
Arachnoid membrane
Sub arachnoid membrane ( contains CSF and aka intrathecal space)
Pia mater
Spinal cord

Question 11

Where does the spinal cord start and where does it end?

Answer 11

Extends from the FORAMEN MAGNUM in the occipital bone to the level of L1. It’s inferior end tapers into the medullary cone - also known as the conus medullaris.