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What is what is the root value of phrenic nerve? and explain in detail?
* Phrenic nerve (C3,C4,C5)- It descends in front of scalenus anterior muscle . * Descends down to enters thorax where it lies between subclan vein(in front) and subclan aery lies behind it . * Fuher it descends in front of hilum of the lungs (whereas vagus nerve descends behind the hilum of lungs) * It is mixed nerve sensory and motor.(both motor and sensory to diaphragm)