Introduction
Flat feet is the most common foot deformity known. In fact, sixty million Americans or 25% of the U.S. population have flat feet [1]. Some of these people may experience problems that limit their activities, while others can run marathons or play in the NBA. The good news is that the vast majority of cases, especially in children, require only conservative (non-surgical) treatment, if any at all.
What is Flat Feet?
If you've ever seen your footprints in the sand and they looked more like bricks than feet, then you probably have flat feet. Simply stated, a flat foot is a foot that does not have an arch when standing. In the medical world, flat feet are associated with "pronated" feet. Pronated is merely the term used to describe the position of the foot when it is flexed upward (dorsiflexed), turned away from the body (abducted), and the heel is rolled outward (everted), all at the same time. A certain amount of pronation is required for normal walking, but too much pronation is often considered a foot's "worst enemy." Over time, excessive pronation can lead to many unpleasant problems including heel pain, bunions, hammertoes, shin splints, and even knee, hip, or back pain. In fact, in his private practice, orthopedic surgeon Dr. Pryce discovered that 95% of his total knee replacement patients and 90% of his total hip replacement patients had flat feet [1]. An easy way to tell if you pronate too much is to take a look at your athletic shoes-excessive wearing of the inside heel (arch side of the shoe) as compared to the outside is a classic indication of excessive pronation.
The normal foot is made up of 28 bones, 30 joints, 128 ligaments, 22 muscles, and 49 tendons. These structures are all arranged in such a way as to be rigid enough to support the weight of the body at certain times, yet flexible enough to conform to the contours of the ground and absorb shock at others. During every step taken while walking or running, the foot switches from rigid to flexible and back to rigid. The focal structure of this ability is the arch. When the arch is high, the foot is rigid for support or pushing off. When the arch is low (as occurs with pronation), the foot is flexible for conforming. So you see, if the arch is fixed in a position too high or too low, or if it is unable to switch back and forth, the foot cannot function properly