Vascular supply of the spinal cord, dermatomes and myotomes Flashcards
Describe the arterial supply
- 2 sources of supply
- Found in subarachnoid space
- Longitudinal arteries
- Segmental arteries
What are the longitudinal arteries
- 2 posterior spinal arteries - branches of vertebral and posterior inferior cerebellar arteries
- 1 anterior spinal artery - branch of vertebral artery
What are the segmental arteries
They enter via the intervertebral foramina
- Cervical (arise from vertebral arteries)
- Thoracic (arise from intercostal arteries)
- Lumbar (arise from lumbar arteries)
Where are longitudinal veins
On surface of cord
Where is the internal vertebral venous plexus
Lies in extradural fat of epidural space
What does the external vertebral venous plexus do
Drains medullary cavity of the vertebral bodies and connects to segmental veins
What is the sclerotome
Cells in the ventral and medial walls of the somite shift their position to surround the neural tube and notochord
What do dorsomedial muscle cells give rise to
Intrinsic back muscles
What do ventrolateral muscle cells give rise to
All other trunk and limb muscles
What is the myotome
A group of muscles innervated by the same spinal nerve
What does the myotome give rise to
Skeletal muscle
Where are the cell bodies of motor neurons that will supply this myotome located
Anteriorly in neural tube
What is the dermatome
An area of skin innervated by a single spinal segment
What does the dermatome of each somite give rise to
The dermis
Where are the cell bodies of somatic sensory neurons located
In the dorsal root ganglia, which develop from neural crest
