Bones of The Foot

The human body is made up of so many things like bone, cartilages, bone marrow, muscles, blood, etc. Among all these things, bone is considered most important for making our body. In a newly born baby, there are approx 300 bones which because of fusion are converted into 206 bones in adult humans. There are so many functions which are performed by bones like they provide shape to the body, they also protect internal organs like brain, heart, lungs, etc. they also store various important minerals like calcium and phosphate as they help in making bone strong from both inside and outside. It is bone only where red blood cell formation takes place. And apart from this one of the most important functions of bone is by providing movement. 

Bones of Foot

The bones which are present in foot provide mechanical support for all the soft tissues which are present in foot and also help the foot withstand the weight of the body whilst standing and in motion. There are mainly three types of bones present in the foot, they are:

Tarsals – It is a combination of seven irregularly shaped bones. They are located proximally in the foot in the ankle area of the foot. 

Metatarsals – They act as a connection between the phalanges to the tarsals. They are mainly five in number i.e. one for each digit.

Phalanges – The bone is commonly known as bones of the toes. Each toe of a human being has three phalanges – proximal, intermediate, and distal.

Division of Foot

The foot is mainly divided into three regions, they are:

1. Hindfoot: talus and calcaneus

2. Midfoot: navicular, cuboid and cuneiforms

3. Forefoot: metatarsals and phalanges

Anatomy of Foot

A. Tarsals: This bone of foot is organised in three rows, they are proximal, intermediate and distal. 

Proximal is commonly known as hindfoot. The proximal tarsal is made up of talus and calcaneus. And they are made up of the hindfoot, forming the bony framework around the proximal ankle and heel.

Talus: Talus is considered as the most superior of the tarsal bones. Its main function is the distribution of whole body weight to the foot. Talus mainly has three articulation they are:

• Superiorly – ankle joint i.e. between the talus and the bones of the leg (the tibia and fibula).

• Inferiorly – subtalar joint i.e. between the talus and calcaneus.

• Anteriorly – talonavicular joint i.e. present between the talus and the navicular.

Main Function of Talus: 

1. One of the main functions of the talus is to transmit forces from the tibia to the heel bone (known as the calcaneus).

2. There are various ligaments which are attached to the talus. 

Calcaneus: it is considered as the largest tarsal bone and lies just beneath the talus where it makes the heel portion. Calcaneus mainly has two articulations, they are: superiorly (between calcaneus and talus) and anteriorly ( between the calcaneus and the cuboid).

B. Metatarsals

They are located in the forefoot i.e. area between the tarsals and phalanges. They are numbered I-V (medial to lateral). The structures of each metatarsal are similar in nature. 

They are of convex shape from the dorsal side and have head, neck, shaft, and base from distal to the proximal end. 

Metatarsals mainly have three or four articulations:

• Proximally (tarsometatarsal joints) i.e. they are present between the metatarsal bases and the tarsal bones.

• Laterally (intermetatarsal joint) i.e. they are present between the metatarsal and the adjacent metatarsals.

• Distally (metatarsophalangeal joint) i.e. they are present between the metatarsal head and the proximal phalanx.

C. Phalanges

They are mainly the bones of the toes. They are similar in structure to the metatarsals as each phalanx consists of a base, shaft, and head.