Anatomy of the spine Flashcards
What is the natural shape of the spine?
Sigmoid - ‘S’ shaped
How many cervical vertebrae are there?
7
C1 - C7
How many thoracic vertebrae are there?
12
T1 - T12
How many lumbar vertebrae are there?
5
L1 - L5
How many sacral vertebrae are there? What is unique about these?
5
But they are fused
How many coccyx vertebrae are there? What is unique about these?
4
They are fused
How many vertebrae are there in total?
33
How many spinal nerves are there?
31
Name the cervical vertebrae that have a different structure to the rest.
C1 and C2
What is the name given to C1?
Atlas
What is the name given to C2?
Axis
What is distinctive about thoracic vertebrae?
Spinous process is thinner and more descending
Vertebral foramen is circular
Costal facets are present (for ribs!)
What is distinctive about lumbar vertebrae?
Spinous process is thick and broad
Vertebral foramen is triangular
What is distinctive about cervical vertebrae?
Presence of transverse foramen
Spinous process is usually bifid
What is different about C7?
The spinous process is large - vertebra prominens
What travels through the transverse foramina?
Vertebral artery and sympathetic chain
What goes through the vertebral foramina?
Spinal cord
Name the attachments of the rib to the thoracic vertebra?
Superior costal facet - head of rib
Transverse costal facet - tubercle of rib
Name the two parts of intervertebral discs.
Outer - Anulus fibrosus
Inner - Nucleus pulposus
What’s the role of intervertebral discs?
Hold vertebrae together, act as shock absorbers
What is the anulus fibrosus made of?
Type I and II collagen
What is the nucleus pulposus made of?
Soft gel-like substance
Loose fibres suspended in a mucoprotein gel
Name the long ligaments of the spine anteriorly to posteriorly.
Anterior longitudinal ligament
Posterior longitudinal ligament
Ligamentum flavum
Supraspinous ligament
Name the ligament between the spinous processes of vertebrae.
Interspinous ligament
What is the conus medullaris?
The tapered lower end of the spinal cord
What level is the conus medullaris found?
L1 or L2
What is the cauda equina?
When nerves continue to branch out diagonally after the end of the spinal cord (conus medullaris)
What is the filum terminale?
When the Pia mater that surrounds the spinal cord projects directly downwards after the conus medullaris, forming a slender ligament.
What do the nerves that make up the cauda equina innervate? M, S & P
Motor: Pelvic organs, lower limbs, internal & external anal sphincter
Sensory: Perineum
Parasymp: bladder
What is the function of the filum terminale?
Longitudinal support to spinal cord.
