OrgoCoop

2+ Year Member
Aug 13, 2016
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Medical Student
Hi,

Quick question over the dreaded brachial plexus.

Why doesn't the axillary nerve carry fibers from C7 and C8? Don't those form part of the posterior cord which the axillary nerve arises from?

Thanks in advanced.
 

sholamd

2+ Year Member
Jun 27, 2015
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Have you ever seen a guitar "snake" cable? It's for people with lots of connections they need to make who don't want a ton of wires everywhere. I kind of think of the brachial plexus this way. The purple input always leads to the purple output, and even though it's all jumbled together in the black part, the colors never mix. So even though the axillary nerve gets bundled with everything else in the posterior cord, it's still just the fibers from C5 and C6 spinal nerve roots (analogy: the purple and yellow cables) that end up being the axillary nerve.
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Last edited:

akinetopsia

some dude
10+ Year Member
Feb 17, 2008
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The Upside Down
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Have you ever seen a guitar "snake" cable? It's for people with lots of connections they need to make who don't want a ton of wires everywhere. I kind of think of the brachial plexus this way. The purple input always leads to the purple output, and even though it's all jumbled together in the black part, the colors never mix. So even though the axillary nerve gets bundled with everything else in the posterior cord, it's still just the fibers from C6 and C7 spinal nerve roots (analogy: the purple and yellow cables) that end up being the axillary nerve.
View attachment 208674
It's a great analogy, but just to clarify, it's C5/C6 that contribute roots to the axillary nerve.

http://radiopaedia.org/articles/axillary-nerve

http://www.orthobullets.com/anatomy/10136/axillary-nerve