# Arches of Foot > Arches of foot for MBBS Anatomy: medial and lateral longitudinal and transverse arches, spring ligament, muscular stirrup, flat foot and the windlass test. - Canonical URL: https://prepelephant.com/topics/mbbs/anatomy/arches-of-foot - Exam / course: MBBS · Subject: Anatomy - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Arches of Foot", PrepElephant, https://prepelephant.com/topics/mbbs/anatomy/arches-of-foot ## Direct answer Arches, not flat platforms, give the human foot its spring: a high, mobile medial longitudinal arch from the calcaneus through the talus (its keystone at the summit), navicular, three cuneiforms and medial three metatarsals; a low, rigid lateral longitudinal arch of calcaneus, cuboid and lateral two metatarsals; and transverse arches across the cuneiform-cuboid row and the metatarsal heads. Each arch is upheld by three tiers of support — interlocking wedge-shaped bones, ligaments led by the plantar calcaneonavicular (spring) ligament beneath the talar head, and muscles, above all tibialis posterior with peroneus longus forming the stirrup and the intrinsic muscles of the sole. The arches distribute weight across the heel and first and fifth metatarsal heads, absorb shock, and convert the foot between a mobile adapter and a rigid lever — and their failure, congenital or acquired, is the story of flat foot and its opposite, the cavus foot. ## What you must remember - **Medial longitudinal arch members:** calcaneus, talus, navicular, three cuneiforms, first to third metatarsals — highest at the talonavicular joint; the talar head is the keystone cradled by the spring ligament. - **Lateral longitudinal arch:** calcaneus, cuboid, fourth and fifth metatarsals — lower, flatter and in contact with the ground, making the lateral border the weight-bearing border. - **Transverse arches:** the wedge-shaped cuneiforms and cuboid at the midfoot, and the metatarsal heads linked by the deep transverse metatarsal ligament at the forefoot. - **Ligament tier:** spring (plantar calcaneonavicular) ligament — the critical supporter of the talar head; long and short plantar ligaments; plantar aponeurosis, whose tightness rises as the toes dorsiflex (the windlass mechanism). - **Muscular tier:** tibialis posterior (the chief dynamic support, locking the midfoot at midstance), peroneus longus (plantarflexes the first ray), the intrinsics, and the long toe flexors acting as slack-line cables beneath the arch. - **Weight distribution:** the loaded foot stands on a triangle — the heel, and the first and fifth metatarsal heads — which is why these three points carry the calluses and Charcot changes in the diabetic foot. - **Clinical poles:** pes planus, flexible (normal variant, or from ligament laxity) versus rigid (tarsal coalition), and posterior tibial tendon dysfunction causing adult-acquired flatfoot; pes cavus with claw toes, often hiding Charcot-Marie-Tooth disease or a spinal lesion. - **Newborn fact:** infants are flat-footed — the arch is a fat-padded shadow that firms up with walking in the first years. ## The arch that fails in middle age A woman in her fifties who has gained weight describes a year of medial ankle and arch aching, then notices the ankle rolling inward and her footprint widening. This is posterior tibial tendon dysfunction — the arch's dynamic tier giving way in sequence. The tendon, overworked and degenerate, first fails as a shock absorber (medial pain and swelling behind the malleolus), then as a stabiliser: the spring ligament stretches, the talar head collapses medially, the hindfoot drifts into valgus, and the forefoot abducts — "too many toes" visible from behind. She cannot perform a single-limb heel rise — the tibialis posterior locks the midfoot for push-off — and when she does try, the heel fails to invert. Treatment escalates from orthoses and strengthening, through rigid bracing, to tendon transfer and bony realignment — the staging of the operation is the staging of the anatomy's collapse. ## Where students slip Examiners ask the discriminating bedside manoeuvre: can the flat foot form an arch when the patient rises on tiptoe? In flexible flatfoot the arch reconstitutes and the heel inverts — benign; in rigid flatfoot it does not, pointing to tarsal coalition, often with peroneal spasm resisting inversion. The second favourite is the windlass mechanism: dorsiflexing the great toe tightens the plantar aponeurosis, hoisting the medial arch and inverting the heel — the same mechanism a podiatry exam exploits and that barefoot running debates invoke. Candidates who can tie the arch's three support tiers to named clinical failures — spring ligament, tibialis posterior, plantar fascia — turn a list of bones into orthopaedic reasoning. ## Frequently asked questions ### Which bones form the medial longitudinal arch? Calcaneus, talus, navicular, the three cuneiforms and the first to third metatarsals, with the head of the talus as the keystone at its summit. ### Which ligament directly supports the head of the talus? The plantar calcaneonavicular or spring ligament, stretching from the sustentaculum tali to the navicular — its failure contributes to adult-acquired flatfoot. ### How does the windlass mechanism support the arch? Dorsiflexion of the toes winds the plantar aponeurosis around the metatarsal heads like a cable on a drum, shortening it, raising the medial arch and inverting the heel during push-off. ### How is flexible flatfoot distinguished from rigid flatfoot at the bedside? On standing tiptoe the flexible arch reforms and the heel inverts; in rigid flatfoot (often tarsal coalition) the arch stays flat with peroneal spasm resisting inversion. ### Why are the heel and the first and fifth metatarsal heads special in weight-bearing? They form the foot's weight-bearing triangle, so calluses, plantar ulcers and Charcot changes concentrate there in neuropathic feet.