Bilateral Tendon Variation of Extensor Hallucis Longus Muscle: Case Report

Tendon variation of bilateral extensor hallucis longus muscle was encountered in a 54-year-old male cadaver. Extensor hallucis longus muscle terminated by dividing into two tendons on the right and three tendons on the left. The IIst tendon was thinner and terminated in the dorsal face of the proximal phalanx base of the big toe on the right. The IInd tendon also terminated on the dorsal face of the distal phalanx base of the big toe on the right. The Ist tendon was thinner and terminated in the medial of the dorsal side of the 1st metatarsophalangeal joint after proceeding in the medial part of the other two tendons of the foot and in the dorsal part of the 1st metatarsal bone on the left. The IInd tendon was thicker than the other two tendons and it clinged on the dorsal side of the distal phalanx base of the big toe after proceeding on the dorsal side of the 1st metatarsus on the left. The IIIrd tendon was on the lateral of three tendons and terminated on the dorsal side of the proximal phalanx base of the big toe after proceeding on the dorsal part of the 1st metatarsal bone by taking a small tendon from extensor hallucis brevis muscle while proceeding on the dorsal side of the foot on the left. Variations of m. extensor hallucis longus should be considered in foot and ankle surgery. In conclusion, this type of variations of extensor hallucis longus muscle tendon may be used to correct big toe deformities, tendon ruptures or reconstructive surgery.