Abduction and lateral rotation of shoulder is caused by nerve roots -

Ans. is 'c' i.e., C5 C6 o Abduction and lateral rotation of arm (shoulder) is caused by C5C6 nerve roots. Therefore, in Erb's palsy (C5C6 damage), the arm is adducted and medially rotated. Clinical features of Erb's palsy A) Muscles paralysed: Mainly biceps brachii, deltoid, branchialis and brachioradialis. Partly supraspinatus, infraspinatus and supinator. B) Deformity (position of the limb) i) Arm : Hangs by the side; it is adducted and medially rotated. ii) Forearm : Extended and pronated. The deformity is known as 'policeman's tip hand' or 'porter's tip hand'. C) Disability : The following movements are lost. o Abduction and lateral rotation of the arm (shoulder) o Flexion and supination of the forearm. o Biceps and supinator jerks are lost. o Sensations are lost over a small area over the lower part of the deltoid.