In the cervical spine, the nerves exiting the spinal cord are named for the inferior vertebrae. For example, C3 exits between C2 and C3.
Then between C7 and T1, there is a C8 nerve.
And subsequently, nerves are named for the superior vertebrae. For example, T2 exits between T2 and T3.
I haven't heard a reasonable explanation for why this is done, besides to confuse medical students.
So if it wasn't done this way (I agree btw); where would you put the "extra" nerve and what would you call it?
ReplyDeleteWhat everyone said below. Add an extra one at the beginning or end.
DeleteI agree. Why couldn't they have just named it C0 instead of C1, and gone down from there??
ReplyDeleteThey could have said that C1 was the 13th cranial nerve. Called it the Extraneous nerve, since it pretty much does nothing.
ReplyDelete1st year vet student here that was completely baffled by this concept until recently...
ReplyDeleteDid it have to do with where the nerve ended up and what it does? So it may have made more sense to group it with the cervical nerves rather than thoracic?
ReplyDeleteAt least, that theory made sense until I went back to my anatomy notes and realized T1 gets up in that brachial plexus, too...
To fuck with future medical students' heads.
ReplyDeleteThen there's the sympathetic nerve supply to the pupil. Why is it LEAVING the brain and then coming right back up??
DeleteOr the 4th cranial nerve. It doesn't even exit in the right direction.
Who designed this stuff??
It's not nice. I don't like it.
ReplyDeleteI vaguely remember some explanation involving the embryological origins, the contribution of somites to each nerve and a general feeling of confusion. I think there is a legit reason why it's this way but it's so esoteric as to be clinically irrelevant.
ReplyDeleteAlso done for the sole purpose of torturing med students - the two buccal nerves. They try to rationalize this by saying one is the buccal nerve while the other is the buccal "branch" of the facial nerve, but they ain't foolin' anybody. RUDE, anatomists, rude.
ReplyDelete