One of the most common causes of foot and leg discomfort is a condition known as over pronation. Normal pronation, or "turning inward", of the foot is necessary as the foot adapts to the ground. With over pronation, however, the arch flattens, collapses, and soft tissues stretch. This causes the joint surfaces to function at unnatural angles to each other. When this happens, joints that should be stable now become very loose and flexible. At first, over pronation may cause fatigue. As the problem gets worse, strain on the muscles, tendons, and ligaments of the foot and lower leg can cause permanent problems and deformities.
There are many causes of flat feet. Obesity, pregnancy or repetitive pounding on a hard surface can weaken the arch leading to over-pronation. Often people with flat feet do not experience discomfort immediately, and some never suffer from any discomfort at all. However, when symptoms develop and become painful, walking becomes awkward and causes increased strain on the feet and calves.
Because pronation is a twisting of the foot, all of the muscles and tendons which run from the leg and ankle into the foot will be twisted. In over-pronation, resulting laxity of the soft tissue structures of the foot and loosened joints cause the bones of the feet shift. When this occurs, the muscles which attach to these bones must also shift, or twist, in order to attach to these bones. The strongest and most important muscles that attach to our foot bones come from our lower leg. So, as these muscles course down the leg and across the ankle, they must twist to maintain their proper attachments in the foot. Injuries due to poor biomechanics and twisting of these muscles due to over-pronation include: shin splints, Achilles Tendonitis, generalized tendonitis, fatigue, muscle aches and pains, cramps, ankle sprains, and loss of muscular efficiency (reducing walking and running speed and endurance). Foot problems due to over-pronation include: bunions, heel spurs, plantar fasciitis, fallen and painful arches, hammer toes, and calluses.
You can test for pronation by looking at the leg and foot from the back. Normally you can see the Achilles Tendon run straight down the leg into the heel. If the foot is pronated, the tendon will run straight down the leg, but when it lies on the heel it will twist outward. This makes the inner ankle bone much more prominent than the outer ankle bone.
Non Surgical Treatment
Supportive orthotics in the shoe is a method commonly implemented to treat many common running injuries associated with pronation. An advantage of orthotics is that they often allow the sufferer to continue to participate in athletic activity and avoid other treatment options that could be potentially costly and time consuming. Seventy-five percent of injured runners are successfully treated with the prescription of orthoses. Orthotics are the most effective treatment for symptoms that develop from unusual biomechanics within the body such as overpronation, resulting in either great improvement or complete healing of the injury in about half the cases.
Depending on the severity of your condition, your surgeon may recommend one or more treatment options. Ultimately, however, it's YOUR decision as to which makes the most sense to you. There are many resources available online and elsewhere for you to research the various options and make an informed decision.