The cause of pain is usually complex, related to the following disorders:
longitudinal flat foot turning outwards (hallux valgus deformation);
too-short Achilles tendon;
bony outgrowths;
inflammation of the plantar fascia (fasciitis).
The diagnosis is confirmed with an X-ray exam. A radiograph shows mineral deposits. It is important to remember that although at first the patient may feel pain only in one heel, radiographs usually show that there are outgrowths in both heels.