An anatomic study of the Martin-Gruber anastomosis: electrodiagnostic implications.

This study aimed to clarify the morphologic variations of the Martin-Gruber anastomosis (MGA) by tracing the anastomotic fascicles. We used 102 upper limbs, and MGA was found in 39.2%. Among 12 instances of MGA between the branches innervating the flexor digitorum profundus muscle, eight anastomotic branches solely innervated the muscle without crossover from median to ulnar nerve. The results of the present study showed three morphologic features of MGA that could not be detected by an electrodiagnostic method.