After a stab wound injury on shoulder, a man got 'pointing index' while trying to make fist. The nerve injured is:

Median nerve innervates the pronators of the forearm, long finger flexors, and abductor and opponens muscles of the thumb and is a sensory nerve to the palmar aspect of the hand. Injury to median nerve leads to 'pointing index'. It is the condition when the index finger remains straight while trying to make a fist. This is due to paralysis of both the flexors (digitorum superficialis, and lateral half of the digitorum profundus) of the index finger, which occurs in medial nerve palsy at a level proximal to the elbow. The other fingers can be flexed by the functioning medial side of the flexor digitorum profundus, supplied by the ulnar nerve. Must know: Wrist drop: Radial nerve injury Foot drop: Common peroneal nerve palsy Winging of scapula: Long thoracic nerve palsy Claw hand: Low ulnar nerve palsy Ape thumb deformity: Median nerve injury Ref: Essential Ohopaedics By J. Maheshwari, 4th edition, Page 60, 61.