Following anterior dislocation of the shoulder, a patient develops weakness of flexion at elbow and lack of sensation over the lateral aspect forearm : nerve injured is -

Musculocutaneous nerve supplies biceps and brachialis. It also gives sensory supply along the radial side of forearm. When it is damaged, it might show the following. Flexion at elbow weakened (Biceps & Brachialis). Supination of semiflexed elbow is affected (Biceps). Sensory loss on radial side of forearm.