The ankle and bones of the foot

Body weight is mainly carried by two large bones in the foot – the talus bone (which articulates with the tibia and fibula), and the calcaneous (heel bone on which the talus sits)

The joint between the first tarsal (talus) and the tibia and fibula is a synovial hinge joint (the ankle) and only allows movement in a single plane (the sagittal plane) – allowing plantar flexion and dorsi flexion.

There is a synovial gliding joint between the talus and the calcaneous (the second tarsal bone, commonly called the heel bone) that allows inversion and eversion. This is called the sub-talar joint and allows, for example, a runner to make adaptations when running on uneven surfaces. Excessive non-functional movement, during activities such as running, increases the risks of sprains and ligamentous damage

The foot consists of 7 tarsals arranged in two groups and 5 metatarsals which form the major part of the arch of the foot. The tarsals and metatarsals help support the body weight.

The 14 phalanges are much smaller than in the hand, as they have little active function. The big toe has only two phalanges, while all the other toes have three.

footClick to enlarge