Flatfeet are most often hereditary in nature. Flatfeet result from an inherent weakness of the posterior tibial tendon. Over time, if left untreated, the arch continues to collapse. The joints of the foot and ankle become mal-aligned. Patients may eventfully develop painful arthritis in the joints in the foot. Intermittent but chronic pain and swelling of the ankle is the most common symptom. Conservative care, such as custom arch supports can help prevent the need for corrective surgery.