The flexor digitorum brevis or flexor digitorum communis brevis[1] is a muscle which lies in the middle of the sole of the foot, immediately above the central part of the plantar aponeurosis, with which it is firmly united.

Its deep surface is separated from the lateral plantar vessels and nerves by a thin layer of fascia.

It arises by a narrow tendon, from the medial process of the tuberosity of the calcaneus, from the central part of the plantar aponeurosis, and from the intermuscular septa between it and the adjacent muscles.

Slip to the little toe may occasionally be absent, where it may be replaced by a small fusiform muscle arising from the long flexor tendon or from the quadratus plantæ.

This article incorporates text in the public domain from page 491 of the 20th edition of Gray's Anatomy (1918)