The Center for Podiatric Care and Sports Medicine

Falling Flat: Adult Onset Flat Foot

Posted by on Monday, July 9th, 2012


Some are born great, some achieve greatness and some have greatness thrust upon them. (William Shakespeare, Twelfth Night)

You know, it’s the exact same thing with flat feet. Thank you, Mr. Shakespeare!

Yes, really–there are two types of flat foot, pediatric flat foot and adult onset flat foot. Today let’s talk about the ones that are thrust upon you: adult onset flat feet.

What is adult onset flat foot? Feet usually have an arch. Why? As was discovered by architects long ago, arches can support heavier loads. Therefore, your foot’s arch plays a big part in supporting the rest of your body–which is pretty giant in proportion to your feet.

Some people are born with high arches, some with lower arches. When those arches fall, your foot flattens out and you have flat feet.

Why does that happen?! There are a number of causes. Arthritis, Charcot foot, and some neuromuscular conditions can lead to adult onset flat floot. However, the most common cause is posterior tibial tendon dysfunction.

The tibialis posterior muscle runs from your calf to your inner ankle. It helps support the arch of your foot, allows you to turn your foot inward, and lets you stand on your toes. The tendon that connects that muscle to your ankle bone can become inflamed, though, and with enough inflammation, it can tear, stretch, and finally rupture. When that happens, there’s nothing to hold up your arch. Similarly, the tendon itself can begin to weaken, causing inflammation in the area, which will then lead to the eventual rupture.

Why does this happen? There is a hereditary factor–if someone in your family has adult onset flat foot, you won’t absolutely develop it, but chances are better. It’s more common in people who have diabetes, high blood pressure, or who are overweight. Finally, it’s by far most common in women in their 40s and 50s.

Will I know it’s happening or will I just wake up one morning with flat feet? It doesn’t happen overnight. The earliest symptom is pain and swelling in the area around your inner ankle bone (medial malleolus). That’s the bony bump on the inner facing side of your ankle, not far from your arch. If you feel pain there, it’s possible you’re in the very early stages of adult onset flat foot, but the only way to be completely sure is to see a podiatrist at The Center for Podiatric Care and Sports Medicine (212.996.1900). Catching it at this early stage is very helpful, so don’t ignore that symptom.

If the pain goes away, don’t get excited–that may just mean that the tendon has ruptured. Here you may notice your arch dropping and your heel drifting outward. If nothing is done about it, then your ankle joint will become stiff and arthritic. And your feet will be flat.

How is it treated? If you catch it early, there are non-surgical methods that can help prevent your arches from falling. Your podiatrist may recommend anti-inflammatories, possibly an ankle brace, or custom-fit orthotics to put into your shoes to help provide support. If you’re overweight, you may be advised to lose weight (it’s not impossible, and it can even be fun!). Physical therapy can help you strengthen your ankle and possibly correct any walking issues that are causing your posterior tibial tendon to become inflamed. Massage could help with the pain.

If the condition is too far advanced, there are a number of surgical options. A podiatrist may need to replace the posterior tibial tendon with another tendon and realign the heel bones by using screws or plates to hold them in place. If the condition is very advanced, the podiatrist may need to fuse the ankle joints together. This will restore the correct position of the foot and eliminate pain, but may lead to some difficulty walking on uneven surfaces. It still may be your best option, though.

It’s always more fun to avoid surgery, so if you fit the profile of a person who might develop adult onset flat foot, be on the lookout for any pain around your inner ankle bone. If you have that or any other foot or ankle issue, contact The Center for Podiatric Care and Sports Medicine. Dr. Josef J. GeldwertDr. Katherine Lai, and Dr. Ryan Minara have helped thousands of people get back on their feet.



If you have any foot problems or pain, contact The Center for Podiatric Care and Sports MedicineDr. Josef J. GeldwertDr. Katherine Lai, Dr. Ryan Minara and Dr. Mariola Rivera have helped thousands of people get back on their feet. Unfortunately, we cannot give diagnoses or treatment advice online. Please make an appointment to see us if you live in the NY metropolitan area or seek out a podiatrist in your area.