What kind of nervous system is a sciatic nerve?

Words called "the nervous system" selling well in our everyday conversation.
Actually, I employ the all of you and think whether it is often that I hear it.
"Is nervous"; "affect the nervous system"; "wear down the nervous system".
Not to mention this, the nervous system going to our body is called it.
However, health has what kind of nervous system to be concrete, and, among us, one will be to what kind of person knowing whether you play a role how.
There is a thing called the sciatic nerve to the nervous system going over from a waist.
I think whether there is recognition called the bone of buttocks with the hipbone generally, but, as for the very beginning etymology, "the bone which can support a body when I sat down on chairs" means in Greek.
And the sciatic nerve transmits the order from a brain to buttocks and a leg according to the reputation; play an important role.
This nervous system which gives big influence for the exercise function of the lower part of the body part of our body.
I am different, but a pain and numbness run in particular in the parts such as buttocks, the outside and the back of the thigh, a calf, the heel when an obstacle happens for some kind of causes where the nervous system which raised an obstacle transmits information to.
I say sciatic neuralgia for such a symptom, and, as for this symptom, there is not only buttocks and the leg but also the case with the lumbago.