In the proximal forearm it gives rise to the anterior interosseous nerve which innervates the flexor of the thumb (FPL), the flexor digitorum profundus of the index finger (FDP IF), and the pronator quadratus, and terminates in a sensory branch to the bones of the wrist, i.e., the carpal tunnel. Compression of the proximal median nerve results in weakness of these three muscles, and can cause aching pain in the wrist on the basis of the sensory nerve to the carpal bones.
