Flat Feet in Children and Adults
Flat feet, or "pes planus" is caused by a very interesting and intricate fault in the inherited design of a person's foot. Without going into exact detail, I will try to explain why this condition may be problematic.
To understand the problem we must first explore normal or ideal function of the foot when walking. Picture yourself walking and taking a step. Your heel strikes the ground at the beginning of the cycle. This is called heel strike. At this point, the joints in your foot must be locked to absorb the impact of the heel on the ground. In order to do that, the joints move in the foot to a condition we call "supination." Simply put, the arch becomes higher. As we continue the cycle, the front of the foot comes in contact with the ground, and your body weight begins to come directly over the foot. Because the ground terrain can be different, we need the foot to be able to adapt. The foot now "pronates." The arch goes from being high, to being low. This "unlocks" the joints and allows for this adaptive ability.
It is here where flat feet become a problem. If the foot flattens or pronates too much, it is much more difficult for the body to continue the cycle because in order to continue, the bones must reverse themselves and lock again. In other words, the arch must go from low to high now in order to lift your heel and push off with your toes.
If the arch is too low, the muscles in the legs must over work to bring the arch up to continue. This is how pain is produced which we commonly call shin splints. Flat feet also cause ligaments and tendons to become stretched causing tendonitis and bulges on the inside of the foot. If the arch collapses significantly bunions form because the pressure on the inside of the foot at the arch is transmitted to the big toe joint and to compensate, your body rolls itself off the inside of the joint pushing the big toe toward the smaller toes causing a slow subluxation of the joint and a bulge which we call a bunion.
Surgery to "fix" flat feet is devastating and not exact. Orthotics ( prescription arch supports ) are the best treatment in helping this condition and preventing painful conditions that may arise from it.