Tarsal bones
Ossa tarsi
The tarsal bones are seven short bones forming the back half of the foot, from the ankle joint to the bases of the metatarsals.
At a glance
- English
- Tarsal bones
- Latin (TA2)
- Ossa tarsi
- System
- Bone
- Region
- Foot
- In order
- From the talus to the cuboid bone
About the tarsal bones
The tarsus is the group of seven bones that makes up the hindfoot and midfoot. The talus sits on top, gripped between the tibia and fibula at the ankle joint, and rests on the calcaneus, the heel bone, below. In front of the talus on the inner side lies the navicular, and in front of that a row of three cuneiforms, medial, intermediate and lateral. On the outer side the calcaneus meets the cuboid directly. The cuneiforms and cuboid then carry the bases of the five metatarsals at the tarsometatarsal joints.
Compared with the wrist, the bones of the ankle are larger and built to carry weight rather than to give fine movement. The talus has no muscle attachments at all and is mostly covered in cartilage; it passes the load of the body from the leg down to the heel behind and forward to the navicular. The calcaneus, the largest tarsal bone, projects backwards as the heel and gives the calf muscles a long lever through the calcaneal tendon. From its inner face a shelf, the sustentaculum tali, props up the talus and has the tendon of flexor hallucis longus grooved beneath it.
The tarsal bones are fitted together into the arches of the foot. The medial longitudinal arch is formed by calcaneus, talus, navicular and the cuneiforms with the first three metatarsals; the lower lateral arch by calcaneus and cuboid with the fourth and fifth. Across the midfoot the wedge-shaped cuneiforms, broad on the dorsal side and narrow below, make a transverse arch. Inversion and eversion of the foot happen mainly at the subtalar joint between talus and calcaneus and at the transverse tarsal joint, where talus meets navicular and calcaneus meets cuboid. Tibialis posterior, peroneus longus and the plantar ligaments help hold the arches.
Injuries follow the bones' roles. The calcaneus is the tarsal bone most often broken, typically by landing on the heels from a height, and a fall that crushes it may also injure the spine. A fracture of the talar neck can cut off the blood that enters there and leave the body of the talus to undergo avascular necrosis. The navicular is a site of stress fracture in runners, and a sprain of the midfoot ligaments around the second metatarsal base is called a Lisfranc injury.
Anthromica
See the tarsal bones where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
