Basic functional anatomy of the foot and ankle

This intricate area contains 26 bones, 33 joints, 107 ligaments and 19 muscles that combine to hold the structure together, whilst allowing it movement in a variety of ways.

The ankle joint is composed of 3 bones:

  • the tibia, the larger and stronger of the two lower leg bones, which forms the inside part of the of the ankle.
  • the fibula, the smaller bone of the lower leg, which forms the outside part of the ankle.
  • the talus, a small bone between the tibia and fibula and the calcaneus, or heel bone.

Feet can mirror your general health. and conditions such as arthritis, diabetes and circulatory disorders can exhibit their initial signs and symptoms there.

It is more common for women to have foot problems than men, mainly due to footwear fashion and ill fitting shoes.

The foot has 3 arches:

  • medial longitudinal
  • lateral longitudinal
  • transverse

The individual shape of bones and joints, the strength of the muscles and support from a network of ligaments generate these arches.

The foot can be divided into 3 functional joint complexes:

  • rear foot
  • mid-foot
  • forefoot

The function of the joint and ankle:

  • acts as a support base with minimal muscle activity
    provides a mechanism for rotation of the fibula and fibula during gait
  • adapts to uneven terrain
  • provides shock absorption
  • acts as a lever during push off

The movement of the foot occurs on 3 axes:

  • across the ankle joint
  • vertically down the tibia
  • longitudinal along the foot

Muscles of the foot and ankle

During extension of the ankle, tibialis posterior contracts drawing the tibia and fibula together while pulling the fibula inferiorly and slightly into medial rotation. In flexion, the malleoli move apart allowing the tales to move, and the fibula to move superiorly with medial rotation.Í

Fact Sheets


Stress Fractures


Achilles Tendonitis

Short achilles tendon

Plantar Fascitis

Rheumatoid arthritis