AN19.1-7 | Back of Leg & Sole — Glossary

A two-headed superficial calf muscle crossing both knee and ankle joints, the primary plantarflexor most effective with the knee extended

A deep calf muscle crossing only the ankle joint, more important for sustained posture; contains venous sinuses that are a common site for DVT

The Achilles tendon, the thickest and strongest tendon in the body, formed by gastrocnemius and soleus, inserting on the calcaneus

A clinical test for Achilles tendon rupture: squeezing the calf should plantarflex the foot; absence of movement indicates complete rupture

The most important invertor of the foot and dynamic supporter of the medial longitudinal arch; dysfunction causes acquired flat foot in adults

A deep posterior compartment muscle that flexes the great toe and supports the medial longitudinal arch; the 'Harry' in the tarsal tunnel mnemonic

A muscle that unlocks the knee by internally rotating the tibia, initiating flexion from the fully extended position

The larger terminal branch of the sciatic nerve supplying the posterior leg and sole of the foot via medial and lateral plantar branches

The larger terminal branch of the popliteal artery, palpable behind the medial malleolus, dividing into medial and lateral plantar arteries

The 'peripheral heart' — calf muscle contraction compresses deep veins, pumping blood proximally against gravity with valves preventing backflow

Blood clot formation in deep veins, commonly in soleal sinuses during immobility, risking pulmonary embolism

The highest foot arch from calcaneus to metatarsals 1-3 via talus and navicular, supported by the spring ligament and tibialis posterior

The plantar calcaneonavicular ligament providing primary static support to the medial longitudinal arch

Dorsiflexion of toes tightens the plantar fascia, raising the medial arch and converting the foot into a rigid lever for push-off

Pes planus, loss of the medial longitudinal arch; flexible type is usually physiological in children, rigid type indicates pathology

Talipes equinovarus, a congenital deformity with cavus, adduction, varus, and equinus (CAVE); treated by Ponseti serial casting

Inflammation at the calcaneal origin of the plantar fascia causing heel pain worst on first morning steps

Pain under the metatarsal heads from loss of the transverse arch or Morton's neuroma

A perineural fibrosis of the common digital nerve in the 3rd-4th web space causing burning pain between the toes

A fibro-osseous tunnel behind the medial malleolus roofed by the flexor retinaculum containing tendons, posterior tibial artery, and tibial nerve

The larger branch of the tibial nerve, analogous to the median nerve in the hand, supplying medial 3.5 toes

The smaller branch of the tibial nerve, analogous to the ulnar nerve, supplying lateral 1.5 toes and most intrinsic foot muscles

A chronic wound above the medial malleolus (gaiter area) from chronic venous hypertension due to calf pump failure

A life-threatening condition where DVT fragments travel to the pulmonary vasculature, blocking blood flow to the lungs