Case report of the double-headed extensor hallucis longus

We present a case report of double-headed extensor hallucis longus (EHL) with potential clinical significance.

Cadaveric dissection of the right lower limb of a 70-year- -old at death female was performed for research and teaching purposes at the Department of Anatomical Dissection and Donation, Medical University of Lodz. The limb was dissected using standard techniques according to a strictly specified protocol. Each head and tendon of the muscle was photographed and subjected to further measurements.

During dissection, an unusual type of EHL muscle was observed. It consisted of two muscle bellies, a main tendon and an accessory tendon. Both muscle bellies were located on anterior surface of the fibula and the interosseous membrane. The main tendon insertion was located on the dorsal aspect of the base of the distal phalanx of the big toe, while the accessory tendon insertion was located medially.

The EHL muscle is highly morphologically variable at both the point of origin and the insertion. Knowledge of its variations is connected to several pathologies such as foot drop, tendonitis, tendon rupture, and anterior compartment syndrome.