The plantar fascia is a tough and flexible band of tissue that runs under the sole of the foot. It connects to the heel bone with the bones of the foot and acts as a sort of a shock absorber to the foot. Heel pain (plantar fasciitis) is a foot condition that develops when repeated activities put a strain on the plantar fascia; this thick band of tissue that supports the arch of the affected foot.
Patients diagnosed with plantar fasciitis may also experience heel spurs, which is a bony growth that forms on the heel bone. Sudden damage, or damage that occurs over many months or years, can cause small tears to develop inside the tissue of the plantar fascia. This can soon cause the plantar fascia to thicken, resulting in heel pain. In addition, the surrounding tissue and the heel bone can also sometimes become inflamed.