You are about to leave jnjmedicaldevices.com. By clicking to continue, you will be taken to a web site governed by their own Legal and Privacy Policies.
Understanding Foot Anatomy
Did you know each foot is made up of 28 bones, 30 joints and more than 100 muscles, tendons and ligaments? Here's a look at the main structures of the feet.
Find a Doctor
- Talus – the bone on top of the foot that forms a joint with the two bones of the lower leg, the tibia and fibula
- Calcaneus – the largest bone of the foot, which lies beneath the talus to form the heel bone
- Tibia – the inner and typically larger of the two bones between the knee and the ankle (or the equivalent joints in other terrestrial vertebrates), parallel with the fibula
- Fibula – the outer and smaller of the two bones between the knee and the ankle in humans (or the equivalent joints in other terrestrial vertebrates), parallel with the tibia
- Tarsals – five irregularly shaped bones of the midfoot that form the foot's arch. The tarsal bones are the cuboid, navicular and medial, intermediate and lateral cuneiforms.
- Metatarsals – five bones (labeled one through five, starting with the big toe) that make up the forefoot
- Phalanges (singular: phalanx) – the 14 bones that make up the toes. The big toe consists of two phalanges – the distal and proximal. The other toes have three.
- Sesamoids – two small, pea-shaped bones that lie beneath the head of the first metatarsal in the ball of the foot
Joints in the feet are formed wherever two or more of these bones meet. Except for the big toe, each of the toes has three joints, which include:
- Metatarsophalangeal joint (MCP) – the joint at the base of the toe
- Proximal interphalangeal joint (PIP) – the joint in the middle of the toe
- Distal phalangeal joint (DP) – the joint closest to the tip of the toe
Each big toe has two joints:
- Metatarsophalangeal joint
- Interphalangeal joint
The surfaces of the bones where they meet to form joints are covered with a layer of cartilage, which allows them to glide smoothly against one another as they move.
Twenty muscles give the foot its shape, support and the ability to move.
The main muscles of the foot are:
- The tibilias posterior, which supports the foot's arch
- The tibilias anterior, which allows the foot to move upward
- The tibilias peroneal, which controls movement on the outside of the ankle
- The extensors, which help raise the toes, making it possible to take a step
- The flexors, which help stabilize the toes
Tendons and Ligaments
Many tendons attach these muscles to the bones and ligaments that hold the bones together to maintain the foot's arch.
The main tendon of the foot is the Achilles tendon, which runs from the calf muscle to the heel. The Achilles tendon makes it possible to run, jump, climb stairs and stand on your toes.
The main ligaments of the foot are:
- Plantar fascia – the longest ligament of the foot. The ligament, which runs along the sole of the foot, from the heel to the toes, forms the arch. By stretching and contracting, the plantar fascia helps us balance and gives the foot strength for walking.
- Plantar calcaneonavicular ligament – a ligament of the sole of the foot that connects the calcaneus and navicular and supports the head of the talus
- Calcaneocuboid ligament – the ligament that connects the calcaneus and the tarsal bones and helps the plantar fascia support the arch of the foot