Anatomical Variations of Flexor Muscles in Sole

Abstract

Variations in the intrinsic muscles of sole are relatively uncommon. There are 18 intrinsic and 4 extrinsic tendons in the sole of foot. These muscles are subjected to variations which are usually encountered during surgery or cadaveric dissections. During routine cadaveric dissection we came across a combination of variations in sole dissection. There was variation in number of flexor digitorum brevis and variation in the origin of flexor digitorum accessorius. The intertendinous connection between flexor digitorum longus and flexor hallucis longus was also observed. The flexor digitorum brevis muscle, in particular its fourth slip, has a significant clinical and surgical importance in medical practice. The knowledge of the frequency of flexor digitorum brevis fourth slip agenesis and variations in relation to the demographic characteristics of patients is of importance for tendon repair, tendon transfer or soft tissue reconstruction in foot surgery. The exact anatomical knowledge of crossing of Flexor Digitorum Longus and Flexor Hallucis Longus in the foot is essential to facilitate tendon harvesting with less morbidity and explain possible reasons for postoperative functional loss. The understanding of variations of sole muscle is very useful to orthopedic surgeons, radiologists and podiatrists for analyzing foot function and for biomechanical modeling of the foot.