Innervation Motor superficial volar forearm group Pronator teres Flexor carpi radialis Palmaris longus intermediate group Flexor digitorum superficialis deep group Flexor digitorum profundus (lateral) Flexor pollicis longus Pronator quadratus hand 1st and 2nd lumbricals Opponens pollicis Abductor pollicis brevis Flexor pollicis brevis Origin Brachial plexus C5-T1 roots medial and lateral cords Course Anterior compartment of arm anterior compartment (anteromedial to humerus) runs with brachial artery (lateral in upper arm / medial at elbow) no branches in the arm Forearm enters the forearm between the pronator teres and biceps tendon travels between flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) then emerges between the FDS and flexor pollicis longus (FPL) Hand the nerve then enters the hand via the carpal tunnel, along with the tendons of the FDS, FDP and FPL Terminal branches anterior interosseous branch (AIN) innervates the deep volar compartment of forearm except the ulnar half of the FDP palmar cutaneous branch supplies sensory innervation to lateral palm recurrent branch (to thenar compartment) digital cutaneous branches supply the radial 3 1/2 digits (palmar) can also supply the index, long, and ring fingers dorsally Clinical Conditions Carpal Tunnel Syndrome AIN Neuropathy Pronator Syndrome