A two-headed accessory muscle on the sole of the foot

Abstract

Anatomical variations include the absence of a muscle or tendon or its presence as an accessory muscle or tendon. Clinically, anatomic variations play an important role in diagnosis and theraphy. In anatomy dissection laboratory, during routine dissection for educational purposes, a 83 -year- old male cadaver was dissected and a two-headed accessory muscle was observed on the plantar surface of the left foot. The medial and lateral heads of the muscle were observed close to the medial and lateral plantar neurovascular bundles. The accessory muscle was pierced by the tendon of the flexor digitorum longus muscle and both muscles were inserted to the distal phalanx of the fifth toe. The variations of the accessory muscles should be taken into consideration in surgical interventions, since, they may change the course of the intervention or as in the case of abductor hallucis muscle, they may be used in reconstructive procedures as grafts. Therefore, it is crucial for surgeons, orthopedic physicians, and anatomists to have a detailed knowledge of the intrinsic muscles of the foot.