Sacral spinal nerves Flashcards
How many pairs of sacral spinal nerves are there?
5 pairs
what do the sacral spinal nerves form inside the dura
cauda equina
What does each sacral nerve divide into?
anterior and posterior primary ramus
Where do the posterior primary rami of S1-S4 travel?
through the four posterior sacral foramina
Where does the S5 posterior primary rami travel?
Through the sacral hiatus
What happens to posterior sacral rami as you go from superior to inferior?
they decrease in size
What do the posterior primary rami of S1-S4 divide into?
medial and lateral branches
What des the medial branch supply?
adjacent mulifidi
What do the lateral branches supply?
combine with L5 and S4 to supply the skin over the buttocks
The posterior primary rami of S4 and S5 unite with what to supply the skin over the coccyx?
the coccygeal posterior rami
Which anterior primary rami contribute to the sacral plexus?
S1-S4
Which anterior primary rami contribute to the coccygeal plexus?
S4 and S5
How many sacral sympathetic ganglia are there?
3 or 4
How will each anterior primary ramus receive postganglionic sympathetic fibers?
gray ramus communicans
