what is the root value of phrenic nerve?: (A) C3,4,5, (B) C2,3,4, (C) C4,5,6, (D) C5,6,7
Answer is A. * 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)