A high instep is a type of foot structure in which the arch of the foot does not fall flat when bearing weight. This condition, also known as a supinated foot and Pes Cavus, occurs in about 8 to 15 per cent of the population, according to MedicMD.
A podiatrist typically recommends an orthotic shoe insert or a different type of shoe, or possibly both, to treat the discomfort caused by having a high instep. The doctor might order X-rays first to determine the specific bone structure that's causing the problem. MedicMD states that high instep can be congenital or caused by injury or a neuromuscular ailment.