Extensor Indicis Brevis Muscle: Report of a Rare Muscular Variant and Classification Proposal

The current report presented a rare variant of extensor indicis brevis muscle, replacing extensor indicis, in the left hand of an adult male cadaver. The origin of the muscle was reported, for the first time, to be from the distal margins of radius and ulna. The muscle is inserted into the extensor expansion of the index. A new classification for extensor indicis brevis muscle was proposed based on its origin. Awareness of rare anatomical variations would help clinicians and surgeons in accurately managing suspected cases and planning surgical procedures.