Adult Flat Foot Deformity


“Life is like a tree and its root is consciousness. Therefore, once we tend the root, the tree as a whole will be healthy.”- Deepak Chopra

Adult Flat Foot Deformity, as a by product of existing health conditions, is induced by various underlying root causes. Normally as children grow and develop, there is a detectable flat foot condition, which usually goes away with designed treatment, or as the child grows. Adults can have their feet and ankles be compromised by varying internal conditions such as diabetes, which causes loss of feeling in the legs, and ultimately degradation of the joints. While several root causes can result in the final outcome, let us identify what the main contributors are to adult flat foot deformity.

What causes adult flat foot deformity?

 Adult flat foot deformity is a condition that is prevalent predominantly in women. . Pregnancy, due to the additional weight that is induced by a growing child, can affect the mother’s feet and ankles. Additionally, if childhood flat foot was noted in the medical history, the adult will have  a higher possibility of developing adult flat foot deformity due orientation of the tarsal bones.. Posterior tibial tendon (PTT) insufficiency is a cause of acquired flat foot deformity as the tendon is instrumental in the maintenance of the arch of the foot.


The PTT is critical to adult flat foot deformity. The root causes of weakening of the tendon include tendonitis, to tearing induced by either trauma to the leg caused by athletics. A mid-foot injury known as a Lisfranc injury, can also cause the foot to flatten. According to scientific studies, the calcaneonavicular ligament, is the one most affected in the pre-curser to adult flat foot deformity, resulting in what the field calls plantar sag or forefoot abduction.The final result is a flattening of the arch, as the foot is displaced from the talus bone. Your orthopaedic surgeon will be the one to diagnose if you have adult flat foot condition. Other root causes of adult flat foot deformity include:

  1. Interosseous Ligament weakening

  2. Deltoid Ligament weakening - root cause of medial ankle instability

  3. Achilles Tendon tightness

  4. Diabetes induced Charcot foot also induce adult flat foot deformity. Neuropathy, induced by diabetes, is the root cause of Charcot foot.

Symptoms of Adult Flat Foot Deformity

Varying according to the root cause of the condition, the following are the possibilities of symptoms:

  1. Pain along the back of the calf

  2. Swelling of the ankle region

  3. Pain during motion such as walking or standing

  4. Increasing ankle pain as the ankle weakens  

Any adult can develop adult flat foot deformity. With the various root causes highlighted above, with the help of your orthopaedic surgeon, you will be able to find an appropriate path for treatment.


  1. Cleveland Clinic: