Tarsals

Tarsals are a group of seven short articulating bones in each foot situated between the lower end of the tibia and fibula of the lower leg and the metatarsus. They are arranged in two rows, proximal and distal. The proximal row is formed by the talus above, and the calcaneus below, which are connected together anteriorly by the navicular. The distal row contains, from medial to lateral side, three cuneiform bones, and the cuboid. The main function of the tarsals is to aid in weight bearing and shock absorption.

Structure

The tarsal bones are seven in number. They are named the calcaneus, the talus, the cuboid, the navicular, and the first, second, and third cuneiform bones.

Calcaneus

The calcaneus is the largest of the tarsal bones. It is situated at the lower and back part of the foot, serving as a lever for muscles of the calf.

Talus

The talus bone supports the leg and forms the ankle joint with the tibia and fibula.

Cuboid

The cuboid bone is cube-shaped and is located on the outer side of the foot, in front of the calcaneus.

Navicular

The navicular bone is boat-shaped and is located on the inner side of the foot, in front of the three cuneiform bones.

Cuneiform bones

The three cuneiform bones are located in a row on the inner side of the foot, in front of the navicular bone and behind the first, second, and third metatarsal bones.

Function

The tarsal bones contribute to the three arches of the foot which serve as a shock-absorber and ensure the weight of the body is evenly distributed across the foot. They also provide flexibility and movement to the foot.

Clinical significance

Injuries to the tarsal bones, including fractures and dislocations, are common and can result in long-term disability if not properly treated. Conditions such as flat feet or high arches can also be caused by abnormalities in the tarsal bones.

See also

• Foot
• Ankle
• Bone fracture