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Bones

At birth, the bones in our feet are undeveloped—there is actually just one bone, with the remainder made up of a softer material called cartilage. By the time we are three years of age, much of the cartilage has become bone, and by age six all twenty-eight bones have taken shape but are still partly composed of cartilage. Even in the adult, some cartilage remains. About a quarter of the body’s bones are in the feet. During the developmental stage, interfering with natural foot development can severely impact foot function later in life. For convenience, anatomists divide the foot into three main parts: the forefoot, mid-foot, and hind-foot.

 

 

The forefoot bears about half the body’s weight, with the ball of the foot (between the big toe and the rest of the foot) responsible for much of our balance. The four smaller toes are made up of three small bones each, called phalanges. The big toe is called the hallux, and has only two bones (phalanges). Under the big toe (hallux) are two very small, round sesamoid bones within a tendon. The bones of the toes are connected to the longer metatarsal bones that connect to the rest of the foot.