What is Adult Acquired Flatfoot?


Adult acquired flatfoot, also known as posterior tibial tendon dysfunction (PTTD), is the type of flatfoot that people usually get during adulthood.

Normally, the posterior tibial tendon helps us when we walk by helping to support the arch in the foot. However, in Adult Acquired Flatfoot, the posterior tibial tendon has problems supporting the arc, which leads to flatfoot.

This usually happens in one foot, but it can happen in both feet. Most importantly, Adult Acquired Flatfoot can get worse if not treated by a foot doctor early on.

Symptoms of Adult Acquired Flatfoot

How exactly does adult acquired flatfoot happen? The posterior tibial tendon gets overused during activities that place stress on the foot. The symptoms of adult acquired flatfoot may include pain on the inside of the foot and ankle, which appear swollen and red.

As adult acquired flatfoot gets worse, the arch of the foot begins to flatten, toes and the foot itself begins turn outward, while the ankle turns inward.

The pain can move to the outside of the foot, below the ankle. The arch flattens more and arthritis can develop in the foot and in the ankle. This is because the posterior tibial tendon is deteriorating.

Diagnosis of Adult Acquired Flatfoot

Diagnosis of adult acquired flatfoot is usually done by a foot and ankle doctor, who examines the foot, the way you walk, and any x-rays or MRIs that are taken.

Treatment for Adult Acquired Flatfoot

If adult acquired flatfoot is treated early enough, then the treatment may be non-surgical. Here are some of the non-surgical treatments:

  • Your foot and ankle doctor may have you wear a short-leg cast, or special boot, to keep your foot still so that your posterior tibial tendon can heal. You may be told to stay off your foot completely.
  • To give the arch the support it needs, a foot and ankle doctor may have you wear an ankle brace, custom orthotic devices or special inserts (inside your shoes).
  • Ultrasound therapy and exercises may also be recommended by your foot and ankle doctor to help heal the posterior tibial tendon and muscle.
  • Anti-inflammatory drugs like ibuprofen (Advil) can help reduce your foot’s pain and inflammation.

Surgical Treatment for Adult Acquired Flatfoot

If your adult acquired flatfoot hasn’t improved with these non-surgical treatments and/or it has gotten worse, then some type of foot and ankle surgery may be required.

Your foot and ankle surgeon can tell you what type of surgery is best for you. But of course, getting to the foot and ankle doctor early on can help you avoid surgery. Early treatment is the key.

Remember, any type of foot or ankle pain is never normal. A foot and ankle doctor can examine your feet and give you the best course of action.

Please call (626) 447-2184 (Arcadia) or (818) 408-2800 (San Fernando) to speak to a foot and ankle specialist about your foot and/or ankle needs.

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