In Erb-Duchene paralysis, the injury is limited to the

ERB'S PARALYSIS:- upper plexus injury.Caused by a forceful widening of the angle between the head and shoulder which may occur by traction of the arm during the bih of a child or by fall on the shoulder.Involves upper trunk - C5, C6 roots. Leads to typical deformity in the limb- policeman's tip hand/ poer's tip hand. The arm hangs by the side, adducted and medially rotated, the forearm is extended and pronated. 1. Adduction of the arm due to deltoid paralysis.2. Medial rotation of arm-paralysis of supraspinatus, infraspinatus and teres minor.3. Extension of the elbow- paralysis of biceps brachii4. Pronation of forearm- paralysis of biceps brachi5. Loss of sensation over the outer aspect of arm due to C6 spinal nerve involvement.{Reference: vishram singh, page no. 62}