What is flatfoot?

Flatfoot. Photo by Vincent S. Mosca, MD.


Flatfoot is a common foot shape that doctors sometimes call pronated foot. When a person with flatfoot stands up, the arch in the middle of the foot disappears. The foot seems to lie flat on the ground.

  • Types of flatfoot

    There are 3 different types of flatfoot. Knowing which kind your child has helps you and your child’s doctor decide if your child needs treatment and, if so, which kind of treatment.

    • Flexible flatfoot: Almost all children with flatfoot have what is called flexible, or hypermobile, flatfoot. This condition is not painful, causes no disability and does not need any treatment. It always affects both feet.
    • Flexible flatfoot with a short Achilles tendon happens very rarely in young children. It affects both feet and may cause pain and disability.
    • Rigid flatfoot is the least common type. Rigid flatfoot most often shows up in people who have a problem with the bones in their feet (tarsal coalition). About 1 in 4 people with rigid flatfoot has pain and disability. About half of the time, rigid flatfoot affects both feet.
  • Flatfoot in children

    Almost all babies are born with flatfoot. Studies estimate that 80% to 90% of babies born in North America have flatfoot. Studies in other countries have found similar numbers. Most of these babies have flexible flatfoot.

    Children often outgrow flatfoot naturally. But at least 20% of adults in North America have flatfoot. About 25% of these adults have flexible flatfoot with a short Achilles tendon, and 9% have rigid flatfoot.

Flatfoot at Seattle Children’s

  • The compassionate experts you need are here

    Flatfoot is treated by the experts in our Foot and Ankle Deformities Program.

    For the rare cases when surgery is needed, doctors at Seattle Children’s developed the most common operation now used nationally to correct severe, painful flatfoot with short Achilles tendon in adolescents. Doctors use this operation only when other more conservative treatments do not work.

  • Specialists for all of your child’s needs

    To restore or improve your child’s health, function and quality of life, we often use nonsurgical methods (like medicines, physical therapy and braces), recommending surgery only when we believe it will give your child the best results.

    Many of our pediatric orthopedic surgeons have expanded fellowship training in areas such as foot and ankle conditions, sports medicine, tumors, upper extremity surgery, limb deformity, neuromuscular diseases, skeletal dysplasia and spine problems.

    We have the largest group of board-certified pediatric radiologists in the Northwest. Our radiologists have special expertise using ultrasound to look for bone and joint changes so we can work with your child to help prevent future problems. If your child needs imaging that uses radiation, we use the lowest amount possible to produce the best image. We also have a 3D low-dose radiation X-ray machine, called the EOS, for safer full-body 3D images.

Symptoms of Flatfoot

When a child has flexible flatfoot – the kind that needs no treatment – we can see an arch in the foot when the child stands on tiptoe or lets the foot hang down.

When children have rigid flatfoot, which may cause problems, we usually cannot see an arch even when they stand on tiptoe.

If children have pain, it is usually focused on 1 spot in the foot. It is not a general, achy feeling.

Diagnosing Flatfoot

First, we examine your child’s foot and ankle. We look at your child’s feet as they stand up. We may ask your child to stand on tiptoe or dangle their foot in the air as they sit on an exam table.

We also check to make sure the joints in your child’s feet and ankles all move well. If your child’s ankle does not move much, it could mean that the Achilles tendon is shortened or tight. That may be a sign that your child has flexible flatfoot with short Achilles tendon.

If your child’s feet hurt and they have the type of flatfoot that usually is not painful, we may take radiographs to get more information about what may be causing the pain.

Treating Flatfoot

First, we always evaluate your child to find out what type of flatfoot they may have. Your child needs treatment only if flatfoot causes pain or disability.

If your child has normal flexible flatfoot that doesn’t hurt, we recommend no treatment. Your child should wear regular shoes and be treated no differently than if their feet had arches.

  • Nonsurgical treatments for flatfoot

    If your child has general aching pain in the feet or legs after activities, we recommend a simple and inexpensive over-the-counter cushioned arch support or a running shoe with a built-in arch support.

    To treat flexible flatfoot with a short Achilles tendon, we may attempt to stretch the Achilles tendon. It is more difficult to stretch this tendon if your child has flatfoot than it is if they have an average-height arch. It requires us to rotate the foot inward to elevate the arch while the Achilles tendon is being stretched.

    We suggest you avoid using hard arch supports for flexible flatfoot with a tight Achilles tendon. These rigid arch supports, often made of hard plastic, can cause more pain than children have without them.

  • Surgery for flatfoot

    In rare cases, flatfoot is not helped by more conservative treatment and children need surgery to relieve their pain.

    In almost all cases that require surgery, the child is at least 8 years old and their Achilles tendon is short. Surgery involves lengthening the short Achilles tendon, as well as correcting the flatfoot deformity.

    The doctor lengthens the heel bone (calcaneus) using a bone graft inserted on the outer side/edge of the middle of the foot. This procedure is called calcaneal-lengthening osteotomy.

Contact Us

Contact Orthopedics and Sports Medicine at 206-987-2109 for an appointment, a second opinion or more information.

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