Flatfoot, also known as “fallen arches” or Pes planus, is a deformity of the feet in which the arch that runs lengthwise along the sole of the foot collapses to the ground or is not formed at all.

Causes and risk factors

Flat foot is a common condition that can run in families. It is often caused by loose connections between joints and excess fat deposits between foot bones which make the entire foot touch the floor when the child stands up. A rare condition called tarsal coalition can also cause flatfoot. In this condition, two or more bones of the foot join abnormally causing stiff and painful flat feet.

Signs and symptoms

Adults with flatfoot deformity may have one or more of the following signs and symptoms:

  • Inside arch of the foot is flattened
  • Heel bone may be turned outward
  • Inner aspect of the foot may appear bowed out
  • Pain in the foot, leg, knee, hip, or lower back
  • Pain in the heels causing difficultly with walking/running
  • Discomfort with wearing shoes
  • Inability to bear weight on the affected foot
  • Tired, achy feet with prolonged standing or walking


Your doctor will perform a physical examination of your foot and observe you in standing and sitting positions. If an arch forms when you stand on your toes, then the flatfoot is flexible and no further tests or treatment are necessary. If pain is associated with the condition, or if the arch does not form on standing on the toes, then X-rays are ordered to assess the severity of the deformity. A computed tomography (CT) scan is done if tarsal coalition is suspected, and if tendon injury is presumed, a magnetic resonance imaging (MRI) is recommended.


If you do not exhibit any symptoms your doctor may suggest some of the following non-surgical treatments:

  • Activity modification: Avoid participating in activities that cause pain such as walking or standing for long periods of time.
  • Orthotic devices: Your surgeon may advise on the use of custom-made orthotic devices that are worn inside shoes to support the arch of the foot.
  • Physical therapy: Stretching exercises of the heel can provide pain relief.
  • Medications: Pain-relieving medications such as NSAIDs can help reduce pain and inflammation.
  • Shoe modification: Using a well-fitting, supportive shoe can help relieve aching pain caused by flatfoot.

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