The foot (pes), the lower section of the leg, has to bear the entire weight of the body when standing upright and walking. The ankle joint connects the two lower leg bones, the fibula and tibia, with the bones of the foot.
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Leading Medicine Guide Editors
Article overview
The foot: Structure and function
The foot (pes), the lower section of the leg, has to bear the entire weight of the body when standing upright and walking. The top of the foot is called the dorsum pedis and the bottom is called the planta pedis. Foot movements are made possible by muscles, the short foot muscles and the long muscles of the lower leg. The muscles and ligaments are also responsible for tensioning the arch of the foot. The arch of the foot (longitudinal and transverse arch) is designed to absorb body weight.
The three sections of the foot
Three sections of the foot can be distinguished:
The tarsus with 7 tarsal bones (ossa tarsi):
The tarsus is located between the lower leg and the metatarsus. Its seven bones are: Ankle bone (talus), heel bone (calcaneus), navicular bone (os naviculare), cuboid bone (os cuboideum) and 3 cuneiform bones (ossa cuneiformia). The calcaneus is the largest tarsal bone and the attachment point for the Achilles tendon, the thickest and strongest tendon in the human body.
The midfoot (metatarsus) with 5 metatarsal bones (ossa matatarsalia):
The metatarsals are tubular bones and are connected to the toes at the front end via joints. A distinction can be made between the base, shaft and head.
The five toes (digiti pedis) with the toe bones (ossa digitorum pedis):
The big toe (hallux) consists of two phalanges, the other toes of three. Although the gripping function of the toes is largely lost in adults, it can be regained through training.
The two ankles (malleolus) are formed by bone cones of the tibia and fibula.
The ankle joint
The tarsal bone, known as the talus, forms the upper ankle joint (talocrural articulation) with the tibia and fibula of the lower leg. The lower ankle joint (LJJ) is formed from the talus, calcaneus and navicular bone. Strains or tears often occur in the ligaments around the capsule of the upper ankle joint.
Diseases and injuries to the foot and ankle
In addition to ligament strains and ligament tears, which are difficult to distinguish from one another, a fracture (ankle fracture, ankle dislocation fracture) can also occur in the ankle joint. The ankle fracture is the most common fracture of the lower limb.
Malpositions or deformities can affect the whole foot or just individual parts. Congenital or acquired foot deformities are heel foot (pes calcaneus), hollow foot (pes cavus), clubfoot (pes equinovarus adductus et excavatus), kinked foot (pes valgus), flat foot (pes planus), sickle foot (pes adductus), pointed foot (pes equinus, horse foot) and splayfoot (pes transversoplanus).
Other possible conditions in the foot and ankle area include heel spurs (additional bone growth on the heel bone, which can cause severe pain), Achilles tendon rupture (Achilles tendon rupture) and osteoarthritis.
