ABSTRACT

Having transversed the pronator teres muscle, the median nerve divides under the tendinous arch of the FDS into the layer between the FDS and the flexor digitorum profundus (FDP). It later runs between the FDS and the FDP and then between the flexor carpi radialis (FCR) and the palmaris longus (PL) to reach the carpal tunnel. In the forearm, the median nerve branches multiple times to supply all wrist and hand flexors, except the flexor carpi ulnaris and the ulnar portion of the FDP. Prior to entering the carpal tunnel (5 to 8 cm), the median nerve gives rise to the palmaris

branch, which pierces the forearm fascia to innervate the thenar eminence and the radial aspect of the wrist.