Foot Anatomy - Bones, Tendons And Other Parts Of The Foot

Anatomy Of The Foot The foot has 26 bones, 33 joints, and more than 100 muscles, ligaments, and tendons. These important structures strengthen the foot and help to maintain its posture. Some of the important structures of the foot are discussed below   Bones  In the foot, we have three groups of bones 1. Tarsals 2. Metatarsals 3. Phalanges Tarsal bones  These are divided into three groups

Proximal group

The proximal group has two bones namely the talus (ankle bone) and calcaneus (heel bone). The talus articulates superiorly with tibia and fibula making the back of the foot known as hindfoot

Intermediate group

Navicular bone- It lies between the proximal and distal group of tarsal bones

Distal group

In the distal group from lateral to medial, we have one cuboid bone and three cuneiforms (lateral, intermediate, and medial) Metatarsal bones We have five metatarsal bones, they are numbered from one through five from medial to lateral. The head of the first metatarsal bone articulates with two sesamoid bones The sides of the bases of metatarsal bones (from two to five) articulate with each other The fifth metatarsal bone has a prominent tuberosity on its lateral side  Phalanges  These are the bones of toes. We have 14 phalanges in total, two in the great toe and 3 in each other toe Joints There are 33 joints in the foot Ankle joint  It is a synovial hinge joint. It involves talus of tarsal bones and tibia fibula (bones of the leg region) Articular surfaces are covered with hyaline cartilage Plantarflexion and dorsiflexion are possible at this joint Intertarsal joint There are several intertarsal joints. These joints are synovial in nature The following movements are possible here • Inversion • Eversion • Supination • Pronation Transverse tarsal joint This joint is formed between talocalcaneonavicular and calcaneocuboid joint   Muscles The muscles of the foot are arranged in two groups 1. Muscles of sole of the foot 2. Muscles of the dorsum of the foot There are four layers of the muscles of the sole of the foot First layer- Abductor hallucis, Flexor digitorium brevis, Abductor digiti minimi Second layer- Quadratus plantae, Lumbricals (4), Flexor digitorium longus tendon, Flexor hallucis longus tendon Third layer- Flexor digiti minimi brevis, Flexor hallucis brevis, Adductor hallucis Fourth layer- Interossei, Dorsal (4), Planter (3), Paroneus longus tendon, Tibialis posterior tendon Muscles of the dorsum of the foot This group has two muscles 1. Extensor hallucis brevis 2. Extensor digitorium brevis   Tendons and ligaments Tendons and ligaments are very much similar to each other These are soft tissues made up of collagen fibers  Ligaments attach muscles to muscles while tendons attach muscles to bones  Tendons Achilles tendon or Calcaneal tendon It is an important tendon of the foot It is the tough band of fibrous tissue, it connects the calf muscles to the calcaneus (heel) bone  The other tendons of the foot are listed below • The tendon of fibularis longus muscle • The tendon of fibularis brevis muscle • The tendon of tibialis posterior muscle Ligaments Some ligaments of the foot are listed below • Long plantar ligament • Lateral ligament • Anterior talofibular ligament • Medial deltoid ligament   Blood supply Arteries The blood is supplied to the foot by the branches of two main arteries namely posterior tibial artery and dorsalis pedis  Posterior Tibial Artery The posterior tibial artery bifurcates into lateral and medial plantar arteries by entering into the sole. Then the lateral plantar artery joins with the deep plantar artery (the terminal end of dorsalis pedis) and forms deep plantar arch whose branches supply the toes of the foot Dorsalis pedis artery The anterior tibial artery continues to form the dorsalis pedis artery. It enters into the dorsum of the foot and continues as the deep plantar artery and then enters in the sole of the foot by passing between the metatarsal one and two Veins There is an interconnected network of deep and superficial veins in the foot. Deep veins follow the course of arteries and superficial veins drain into the dorsal venous arch.  The great saphenous vein and the small saphenous vein arise from the two sides of the dorsal venous arch. These two veins drain a large amount of blood of the foot Nerve supply There are five main nerves that innervate the foot namely 1. Tibial nerve 2. Deep fibular nerve 3. Superficial fibular nerve 4. Sural nerve 5. Saphenous nerve These five nerves are responsible for the cutaneous or general sensory innervation of the foot   Read more about Foot Anatomy