Flatfoot is also called pes valgus, or pes plano valgus.  It has many causes and it often runs in families. Some of the causes are nerve problems called neuromuscular disorders, like cerebral palsy. People with extremely flexible soft tissue structures often have flatfeet, the so called double jointed person.  Achilles tendons that are too tight will flatten out the foot. This is called EQUINUS (equinogenic flatfoot). TARSAL COALITION (bones growing together that should be separate in the joints in the back of the foot ) of the STJ and MTJ will often produce a flat foot.  Flat feet can be flexible and floppy or they can be without much motion called rigid, such as occurs in tarsal coalitions.

Not all flat feet have problems, yet some of the worst foot problems are often associated with flat feet.  Consider posterior tibial dysfunction. Family history is very important.

Treatment for flatfeet depends on the cause of the flatfoot and the associated symptoms and likelihood of progression.  Early in the course of treatment, supportive devices are often placed in the shoe to favorably position the arch and try to modify the symptoms and progression.  If the flattening is minor, perhaps less control will be necessary and likely a non prescription orthotic will be beneficial.  As the degree of flattening increases, the likelihood of needing a custom device increases and will often be augmented with bracing that comes above the ankle.  If the flatfoot is thought to be caused by a tight achilles tendon and calf muscle (equinus), stretching exercises are often encouraged to attempt to achieve more flexibility in the back of the lower leg.  Since dropping the back of the heel will increase the stretch within the tendon and muscle, effectiveness of stretching programs will be negated by wearing shoes that have a heel that is held above the forefoot.  This is called a positive heel position and is the opposite of what you wish to train the back of your lower leg to do.  If you have an equinogenic flatfoot, wearing a shoe with a heel that is elevated above the front part of the shoe is accelerating your deformity.  You want to progressively lower the back of your heel over your lifetime, so look for low heeled shoes and if you can tolerate it without getting hurt, look for a shoe with a negative heel, the so called Earth Shoe.

If you are unable to achieve flexibility in your achilles and calf and it is thought to be the cause of your foot troubles, you may get a surgical recommendation to lengthen your achilles tendon.  Make sure to exhaust all attempts at conservative care prior to undergoing an achilles tendon lengthening.