Spinal cord anatomy and ascending/descending pathways Flashcards
How many spinal nerves?
31 paired spinal nerves
The spinal meninges are continuous with the cranial meninges via the foramen magnum. True/false?
True
What are the rami of the nerve roots?
The primary rami are branches of the spinal nerve.
Roots vs rootlets vs rami
Nerve rootlets = extend out of the spinal cord medially and combine to form roots.
Nerve roots = form together to then form the spinal nerve.
Rami = after the roots combine together to form the spinal nerve, they then split apart again to form rami.
The dorsal rami is posterior to the ventral rami. True/false?
True. Ventral root = front root
How many ramus come from one pair of spinal nerves?
Each pair of spinal nerves has an right and left anterior ramus and a right and left posterior ramus.
What is the denticulate ligament?
Extensions of the pia mater (faithful mother) in the spine, that anchor the spinal cord to the dura mater.
White matter occupies the inner spaces of the spinal cord. True/false?
False, they occupy the outer spaces.
What does the white matter in the spinal cord consist of?
Axons, glial cells and blood vessels. Occupies a small portion of the cord when descending the cord.
What does grey matter in the spinal cord consist of?
Neuronal soma, cell processes, synapses, glia and blood vessels.
How many parts is grey matter divided into?
4 parts
Left and right posterior horns
Left and right anterior horns
How many main longitudinal arteries supply the spinal cord?
3
The main artery
One anterior and one posterior originating from main
What other main arteries supply the spinal cord?
Segmental arteries - derived from vertebral, intercostal and lumbar arteries.
Radicular arteries - travel along the dorsal and ventral roots.
What happens if there is an embolic occlusion to the spinal arteries?
Will lead to areas of spinal cord infarction
Venous drainage of spinal cord?
Follows a similar pattern to the arterial supply, with both longitudinal and segmental veins.
