Ch 5 Spine Anatomy Flashcards
Sonography of the spine is limited to infants under what age? Why?
6 months due to ossification after
(note: diagnostic value decreases at 3 months)
What is the m/c clinical indication for a spine u/s?
Sacral dimples
What position should the baby be in for a spine u/s?
Prone with rolled up towel/pillow or in decubitus with legs tucked
How many vertebrae is there in the neonatal vertebral column?
33
Vertebrae is separated by ____?
Intervertebral discs
Name the 4 regions of the spine + how many vertebrae they each have?
Cervical: 7
Thoracic: 12
Lumbar: 5
Sacrum: 5
Coccyx: 4
Vertebrae consists of ___ + ___?
An anterior vertebral body + posterior vertebral arch
The vertebral body + arch form an enclosed hole known as ___?
The vertebral foramen
The vertebral foramen lines up to form the ___ which encloses the spinal cord?
Vertebral canal
Does the coccyx have a vertebral arch?
No! Therefore it has no vertebral canal either, which means no spinal cord enters this area
The vertebral body forms the ___ part of each vertebrae?
Anterior
What is a vertebral body?
-Weight bearing part of vertebrae
-Lower portion of spinal column will have larger bodies to support increased weight
The vertebral arch forms the ___ + ___ part of each vertebrae?
Lateral + posterior
Vertebral arches have bony prominences which act as ___ sites for muscles + ligaments?
Attachment
Each vertebra has how many spinous processes?
1 posteriorly
Each vertebra has how many TRV processes?
2, extends laterally + posteriorly from body
What do pedicles do?
Connects vertebral body to TRV processes
What does lamina do?
Connects TRV + spinous processes
What does articular processes do?
Forms joints b/w the stacked vertebrae
What is the spinal cord?
-Long tubular structure made of nervous tissue
-Pathway for info connecting brain + peripheral nervous system
-Originates in brain stem
Where does the spinal cord terminate?
At the conus medullaris b/w L1 + L2
The conus gives way to a fibrous extension called the ___?
Filum terminale
The filum terminale is surround by the echogenic strands of the ___?
Cauda equina
What is the filum terminale?
-Fibrous band that extends from conus medullaris to coccyx
-Extension of the pia mater
What is the filum terminale’s function?
To stabilize/anchor the spinal cord
What is the cauda equina?
-Collection of nerve roots at end of spinal column
-“Horses tail”
When is the conus considered abnormally low?
At or below L3
At what level does the thecal sac terminate?
S2
What does the thecal sac surround?
Whole spinal cord
Is the filum terminale or cauda equina thicker + more echogenic?
Filum terminale (<2mm is normal thickness)
What echogenicity will the coccyx be before + after it ossifies?
Before: hypoechoic
After: echogenic
How to determine level of the conus?
-Take panorama + count backwards from S5 to L1 (there should be 10 vertebrae)
-LSJ (lumbosacral junction) is the curve in the spine where lumber ends + sacral starts (L5/S1)
-Check work by finding last rib + following it back to T12
List 4 main things we assess during a spine u/s?
-Level of conus
-Normal movement of nerve roots (cauda equina) + filum terminale
-Assess for a tract/sinus
-Assess for any masses/cysts
How many lumbar + sacral vertebrae are there?
5 each
The conus normally terminates b/w which vertebrae?
L1 + L2
