Anatomic variants of the muscles of the hand have important clinical implications. We report a case of bilateral extensor digitorum brevis manus (EDBM), a rare muscle found on the dorsum of the wrist and hand in an adult female formalin-fixed cadaver. In both hands the muscle inserted proximally in the dorsal surface of the distal radius and finished inserting in the common extensor tendon of the middle finger. The anatomic and clinical implications of this variant are discussed here.