Alternative Names pes planus, fallen arches, pes planovalgus, excessive pronation, talipes calcaneal valgus
Definition Flat feet is a condition where more of the foot surface is in contact with the floor than normal.
What is going on in the body? A truly flat foot with no arch is rare. Most people with flat feet have flexible arches. When the foot is not bearing weight, it has an arch. As soon as weight is placed on the foot, the arch collapses.
What are the signs and symptoms of the condition? Pes planus may be congenital, or acquired. Acquired causes include:
rupture of the posterior tibial tendon, in the back of the lower leg
People with flat feet have very sore, tired feet after a day of standing. They may also have related pain in the knee, hip, and low back. When a foot becomes flat, the leg often turns, which increases stress on the inside part of the knee. That causes poor positioning of the hips and swaying of the back, leading to pain in these areas.
People with flat feet often develop plantar fasciitis. This is an inflammation of fibrous tissue under the skin of the sole. People with flat feet are also more likely to have bunions and hammertoes.
What are the causes and risks of the condition? People with flat feet can develop chronic fatigue. This can lead to problems with activities of daily living and work. People may avoid exercise if it makes their feet hurt. Lack of exercise can increase the risks of heart disease.
Flat feet often cause a person's lower joints to be positioned oddly. That chronic repetitive stress can lead to osteoarthritis, which is chronic joint pain, or stress fractures of the bones of the foot.
What can be done to prevent the condition? There is really no way to prevent flat feet.
How is the condition diagnosed? The condition can be diagnosed just by looking at the feet. The doctor looks for any change in the arch shape when weight is put on the foot. Often the position of the heel from behind is checked. Instead of standing straight up, the heel rolls to the inside. This rolling is called pronation.
What are the long-term effects of the condition? Long-term effects can include arthritic changes in the feet. These changes can become so severe that surgery is needed to reconstruct the foot.
What are the treatments for the condition? Flat feet can be treated with supportive shoes and inlays for the shoes that support the arch. A good shoe store can help with getting the right shoes. Inlays are available over-the-counter at pharmacies. A doctor can prescribe orthotics, which are inlays customized to fit the person's foot exactly. If this condition becomes severe, surgery may be needed to correct the problem.
What happens after treatment for the condition? Inlays and shoes should be checked often to make sure they are still in good working order. There should be no change in shape. Inlays must continue to support the foot.
How is the condition monitored? People with flat feet should have periodic visits with a doctor.
Author: Bill O'Halloran, DPM Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request