A supernumerary extensor tendon to the thumb with an accessory tendon to extensor indicis.

We present a report of an anatomical variation, the function of which is unclear. An anomalous, independent tendon to the thumb was accompanied by an accessory supernumerary tendon to the extensor indicis. This particular variation has not previously been described and was discovered during routine dissection of a male cadaveric upper limb. It is important to revisit these variations of anatomy as they may be relevant to explain clinical signs or during surgical procedures as detailed in this report.