Flat Foot
Signs and Symptoms

Flat feet don't cause disabilities or other problems as long as the foot is supple and the heel cord, or Achilles tendon, isn't tight. This is called flexible flat foot. A supple foot looks flat when the person stands on the whole foot — referred to as the "loaded" position — but an arch develops when the person gets off the foot (in the "unloaded" position) and when he or she stands on the toes. If the heel cord can be bent up at the ankle more than 15 degrees from the perpendicular to the leg, it is not considered tight.

Although flexible flat feet don't need treatment, two other types of flat feet do:

• Rigid Flat Foot — The foot is flat in all positions, regardless of whether it is loaded, unloaded or the child stands on his or her toes.
• Flat Foot With a Tight Heel Cord — The foot is unable to be bent back at the ankle more than 15 degrees due to the calf muscles, which form the Achilles tendon, being contracted.

These two types of flat feet occur in less than a third of people with flat feet and symptoms can include:

• Pain
• Calluses or redness
• Other evidence of the foot having trouble doing its job

Reviewed by health care specialists at UCSF Children's Hospital.
Last updated February 4, 2010