The tarsus (from the ancient Greek tarsos meaning wedge or ankle) is a set of bones constituting a part of the skeleton of the foot.

Structure. The skeleton of the foot is made up of three parts including the tarsus. (1) Positioned at the back of the foot and in conjunction with the leg, the tarsus is made up of seven bones:

• The talus is the only bone that articulates with the bones of the leg, tibia and fibula (also called the fibula). It also articulates with the navicular bone and the calcaneus.
• The calcaneus is the strongest and largest bone in the foot, forming the heel. It articulates with the talus and cuboid bone, located at the front.
• Cuboid bone is a cubic shaped bone placed towards the lateral face. It is located between the calcaneus in the back and the metatarsus in the front.
• The navicular bone is a flattened barque-shaped bone. Placed towards the medial face, it is located between the talus at the back and the three cuneiform bones at the front.
• The three cuneiform bones are distinguished by their positions. The larger medial cuneiform and the smaller intermediate cuneiform articulate with the navicular bone behind and the metatarsal in front. The lateral cuneiform articulates mainly with the cuboid bone as well as with the metatarsal and navicular bone.

Insertions. The tarsal bones serve as an insertion area for various muscles coming from the leg. The whole tarsus is also supported by numerous joints and numerous ligaments.

Body weight support. One of the main functions of the bones of the foot, including those in the tarsal region, is to support the weight of the body. (2)

Static and dynamic of the foot. The skeleton of the foot, in particular that of the tarsal region, helps maintain the support of the body and perform various movements including propulsion of the body when walking. (2) (3)

Foot bone fractures. The tarsal bones can fracture. The most common is that of the calcaneus, often with a sudden fall on the foot. Fractures of the talus are rarer but can occur when playing certain sports (4).

Epine calcaneenne. Also known as Lenoir’s spine, this heel spine corresponds to the development of an outgrowth in the calcaneus. This is due to the appearance of irritation or inflammation of the plantar fascia, a thick fibrous membrane connecting the phalanges to the heel (5).

Bone pathologies. Some diseases can affect the bones by changing their structures. Osteoporosis is one of the most common conditions. It is linked to a loss of bone density which is usually found in people over the age of 60. It accentuates bone fragility and promotes bills (6).

Medical treatment. Depending on the pathology, different treatments may be prescribed to regulate or strengthen bone tissue, as well as to reduce pain and inflammation.

Surgical treatment. Depending on the type of fracture, a surgical operation can be carried out with the installation of a screwed plate, nails or even an external fixator.

Orthopedic treatment. Depending on the type of fracture, the installation of a plaster or a resin can be practiced.

Medical imaging examination. X-ray, CT, MRI, scintigraphy or bone densitometry examinations can be used to assess bone pathologies.

Medical analysis. In order to identify certain pathologies, blood or urine analyzes can be carried out such as, for example, the dosage of phosphorus or calcium.

“Little Foot” (in French, petit pied) is the name given to a skeleton ofAustralopithecus prometheusdiscovered in 1994 by paleoanthropologist Ronald J. Clarke. It owes its name “Little Foot” to the small size of the foot bones initially found in a box of bones classified as coming from bovines. After the discovery of these small foot bones, the researchers found 90% of the skeleton: “Little Foot” thus became the most complete Australopithecus skeleton discovered to date. After highly variable dating results, a new method has made it possible to date it at 3,67 million years old (7) (8).