All of the following are affected in Erb's palsy EXCEPT

(B) Lower trunk of brachial plexus # Erb's palsy: Most common type when the 5th and 6th cervical nerve roots are involved as in the upper trunk of brachial plexus.> Resulting paralysis causes the arm to lie on the side with extension of the elbow, pronation of the forearm and flexion of the wrist (waiter's tip).> Moro reflex & biceps jerks are absent on the affected side> Treatment consists of use of a splint so as to hold the arm abducted to a right angle and externally rotated> Forearm is flexed at right angle and supinated and the hand is dorisflexed.> Massage and passive movements are advocated.> Fully recovery takes weeks or even months.> Severe injury may produce permanent disability.# Upper root lesions (Erb's palsy): Due to injury of C5, C6 and (sometimes) C7. Abductors and external rotators of the shoulder and the supinators are paralysed. Arm is held to the side, internally rotated and pronated. There may also be loss of finger extension, Sensation is intact.