Arches of the Foot Anatomy
The tarsal and metatarsal bones form two longitudinal arches, medial and lateral. The medial arch is higher, forming the instep of the foot, and consists of the calcaneus, talus, navicular, three cuneiforms, and medial three metatarsals (Figs 6.98, 6.99 & 6.100). The lateral arch comprises the calcaneus, cuboid and lateral two metatarsals (Fig. 6.98). Each arch has an anterior and a posterior pillar, which together transmit body weight to the ground. The posterior pillar of each arch is the same, namely the tubercles on the inferior surface of the calcaneus. However, the anterior pillars are separate, being formed by the heads of the appropriate metatarsals. The arches are important in relation to human bipedalism, as they enhance forward propulsion.