DEAR DOCTOR K: At my son's 12-year well-child visit, his doctor said that he may have flexible flatfeet. What does that mean? Is it something that needs to be treated?
DEAR READER: A person is said to be flat-footed when the foot loses the gently curving arch on the inner side of the sole. That's why flatfeet sometimes are called "fallen arches." If the arch is flattened only when standing and returns when the foot is lifted off the ground, the condition is called flexible flatfoot. If the arch is never present, the condition is called rigid flatfoot. (I've put an illustration of flatfoot on my website, AskDoctorK.com.)
How can parents tell if they or their child have flatfeet? A fairly simple way to get an idea is to find a flat surface that looks different when it's wet, like a concrete floor or walkway. Get your child's feet wet. Then have the child stand on that concrete surface. If you can see the entire bottom of his foot in wet outline, the feet probably are flat.
Flexible flatfeet are considered normal in young children. The arch may not form fully until sometime between ages 7 and 10. Even in adulthood, up to 25 percent of people have flexible flatfeet. In many of these adults, the missing arch is an inherited condition related to loose ligaments, fibrous tissues that connect bones to one another.
Most children and adults with flexible flatfeet never have symptoms. However, their toes may point outward as they walk. A person who develops symptoms usually complains of tired, aching feet, especially after prolonged standing or walking.
A foot specialist will examine your son's shoes to check for signs of excessive wear. Worn shoes often provide valuable clues to poor bone alignment and problems with gait. (Gait describes how your feet and legs move when you walk.) The doctor will ask your son to walk barefoot to evaluate his arches, to check for out-toeing and to look for other signs of poor foot mechanics. The doctor will also examine his feet for flexibility and range of motion and feel for tenderness or bony abnormalities.
When flatfoot does not cause symptoms, no treatment is needed. For mild pain or aching, over-the-counter pain relievers may be effective.
Surgery to improve foot alignment is typically a last resort for people with significant pain that does not respond to other therapies.
Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK.com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.