Clinico-anatomical description of an accessory flexor pollicis longus.

Several instances of accessory musculature of the upper extremity are now recognized. During regular dissection class of undergraduate medical students, we observed an important anatomic variation pertaining to the flexor pollicis longus muscle (FPL) in the left upper limb of an adult male cadaver. An accessory muscle belly extending from the deep aspect of flexor digitorum superficialis (FDS) to the tendon of the FPL was observed in the flexor surface of the antebrachium. The description of Gantzer's muscle (GM) is well elucidated in anatomical archives and is described as an accessory muscle extending from the superficial to the deep flexors of the digits.