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What Is Flatfoot?

Flatfoot is also called posterior tibial tendon dysfunction. The posterior tibial tendon attaches the calf muscle to the bones on the inside of the foot. Its job is to hold up the foot’s arch and support the foot while walking. When the tendon becomes inflamed or turned and is no longer able to support the foot, the arch falls without support, resulting in flatfoot.


Symptoms of flatfoot include:

  • Pain and possibly swelling along the inside of the foot and ankle
  • Pain on the outside of the ankle
  • Pain that gets worse with activity

Causes and Risk Factors

Flatfoot can result from an acute injury such as a fall, or from repeated use. High-impact sports such as basketball, tennis, soccer and running can cause tendon dysfunction over time. Chronic conditions and age-related wear and tear can also cause flatfoot.

Factors that increase the risk of flatfoot include:

  • Being female
  • Being over 40 years of age
  • Diabetes
  • High blood pressure
  • Obesity


A physical exam is an effective way to diagnose flatfoot. Doctors look for swelling along the tendon, which runs from the calf to the inside of the ankle and foot. People with flatfoot may have heels tilted outward, and their ankle range of motion and flexibility may be reduced.

Doctors also use the “too many toes” sign. Only the fifth and a portion of the fourth toes are seen when looking at a healthy foot from the heel side. With flatfoot, more toes can be seen. Being unable to stand on one leg and raise the heel is another sign of flatfoot.

Imaging scans are also useful in the diagnosis of flatfoot. A weightbearing X-ray can be used to detect deformities, while an MRI can rule out other conditions of the posterior tibial tendon as well as check for the presence of degenerative changes.


Flatfoot symptoms may take a long time to heal. Pain may last for six months or more after treatment begins. Even if the condition is caught early, pain may persist for up to three months after starting treatment.

Despite the difficulty in healing, nonsurgical treatments can be effective in reducing symptoms. These include:

  • Ice
  • Leg cast, boot or brace
  • Lower-impact exercise such as biking, swimming or using an elliptical machine
  • Nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen
  • Physical therapy
  • Reduction or elimination of activities that cause pain
  • Specialized shoe inserts called orthotics, which are the most common flatfoot treatment

If pain lasts longer than six months after beginning treatment, surgery may be necessary. There are a number of surgical methods of treating flatfoot, including:

  • Fusion: Often used when there is also arthritis in the foot joints and the foot is not flexible enough for other methods to be effective, this technique removes the cartilage from the affected joints. The joints will then heal together into one bone, which eliminates joint pain at the cost of some foot movement. The bones are usually held in position by internal hardware.
  • Gastrocnemius recession or Achilles tendon lengthening: This surgery lengthens the calf muscles. It can prevent the recurrence of flatfoot. These procedures are usually used in combination with other surgical treatments and may be required to achieve corrected foot position at the time of surgery.
  • Osteotomy: This surgery cuts and shifts bone—normally the heel bone—to give the arch a shape that is closer to normal. The bone is usually held in position by internal hardware.
  • Tendon transfer: The tendon is replaced with another tendon from the same foot, generally a tendon that moves the toes. Losing this tendon will not affect walking.
  • Tenosynovectomy: Used when the only symptom is pain and there is no deformity of the foot, this surgery clears away inflamed tendon tissue.

If you are seeking treatment for flatfoot, click on the link below and schedule an appointment. Someone will get back to you as soon as possible. Thank you for choosing Summit Health.

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