Figure 1

Location of the quadratus plantae muscle. Plantar view shows inserting tendon of flexor digitorum longus and quadratus plantae, part of the second layer of intrinsic foot muscles [12]. Quadratus plantae lateral (QPL) and medial (QPM) heads originate from the calcaneus (C) and insert on flexor digitorum longus (FDL). Rectangular boxes indicate the location from which muscle samples were excised.