Applied anatomy of the lower leg, ankle and foot

The functional terminology in the foot is very misleading, because the same terms are often used for very different things. The following definitions and explanations are used here: • Plantiflexion–dorsiflexion indicate movement at the ankle. Plantiflexion is movement downwards towards the ground, and dorsiflexion upwards towards the tibia. There is also a plantiflexion–dorsiflexion movement at the midtarsal joint. • Varus–valgus: these movements occur at the subtalar joint. In valgus, the calcaneus is rotated outwards on the talus; in varus, the calcaneus is rotated inwards on the talus. • Abduction–adduction: these take place at the midtarsal joints. Abduction moves the forefoot laterally and adduction moves the forefoot medially on the midfoot. • Pronation–supination are also movements at the midtarsal joints. In pronation, the forefoot is rotated big toe downwards and little toe upwards. In supination, the reverse happens: the big toe rotates upwards and the little toe downwards. Sometimes the terms internal rotation and external rotation are used to indicate supination or pronation. • Inversion–eversion: these are combinations of three movements. In inversion, the varus movement at the subtalar joint is combined with an adduction and supination movement at the midtarsal joint. During eversion, a valgus movement at the subtalar joint is combined with an abduction and pronation movement at the midtarsal joint.