A flat foot occurs when the normal arch is lost and is often associated with ankles that are angled outwards.

Twenty percent of adults have flat feet, and nearly all babies are born without the normal adult arch. Most flat feet are “flexible,” cause no problems, and do not require treatment. A third of them are “rigid,” produce symptoms, and are best treated. Rigid flat feet that need treatment can be identified by symptoms and by examination of the foot.

Causes

Flat feet are the mildest of many developmental (congenital) problems of the feet, the causes of which are not known. Lax joints (being “double jointed”) tend to run in families and produce flat feet along with unusual flexibility of other joints. Occasionally, they result from a ruptured ankle tendon, a foot injury, cerebral palsy, spina bifida, or muscular dystrophy.

Risk Factors

The following factors increase your chances of developing flat feet:

• Familial tendency

• Foot injuries

• Diseases that cause muscle imbalance, such as cerebral palsy, spina bifida, or muscular dystrophy

Symptoms

If you experience any of these symptoms do not assume it is due to flat feet. These symptoms can be due to many types of foot problems including ill-fitting shoes. If you suffer from any one of them, see your physician or podiatrist.

• Pain

• Calluses or redness

• A stiff foot

• Weakness or numbness of the foot

• Rapid wearing out of shoes

• Worn shoes lean towards each other

• Other evidence, such as difficulty running, that indicates the foot is having trouble doing its job

Diagnosis

Your doctor will ask about your symptoms and medical history, and will perform a physical exam. If the flat foot is fixed and symptomatic, you will be referred to an orthopedic surgeon for possible surgical correction.

If either of these tests are positive, the flat foot is flexible and unlikely to need treatment:

• The arch appears when standing on tiptoe

• The ankle can be flexed at least 15° up from perpendicular to the lower leg

Treatment

Talk with your doctor about the best treatment plan for you. Treatment options include the following:

Physical therapy, exercises, and orthotics

If you have mild symptoms, certain exercises, physical therapy, and shoe inserts may relieve the discomfort. A well-fitting pair of shoes may be all that is needed. Flat feet due to nerve or muscle disease may need special braces.

Surgery

For rigid flat feet, a surgical procedure can create a satisfactory arch.

Prevention

To help reduce your chances of getting flat feet, take the following steps:

• Wear well-fitted shoes with adequate arch support.

RESOURCES:

American Academy of Family Physicians
http://familydoctor.org

Orthopaedic Department
University of California, San Francisco
http://orthosurg.ucsf.edu

Wheeless' Textbook of Orthopaedics
Duke Orthoapedics
http://www.wheelessonline.com

CANADIAN RESOURCES:

Flat Foot
Calgary Foot Clinic
http://www.foottalk.com/d_flatfoot.html

Pes Planus (Flat Foot)
Workplace Safety and Insurance Appeals Tribunal
http://www.wsiat.on.ca/english/

References:

Flat Feet. British Orthopaedic Foot Surgery Society website. Available at: http://www.bofss.org.uk/html/flat_feet.shtml. Accessed August 7, 2005.

Flat Foot. UCSF Children’s Hospital website. Available at: http://www.ucsfhealth.org/childrens/medical_services/ortho/foot/conditions/flatfoot/signs.html Accessed August 9, 2005. Accessed August 7, 2005.

Pes Planus.DynaMed website. Available at: http://www.dynamicmedical.com/dynamed.nsf?opendatabase. Accessed August 7, 2005.