Feet are supposed to roll inward as a part of every step you take. This helps them to mold to the various terrain that they step on (sand, rocks, various obstacles) without injury. This is called pronation. But, when your feet roll inward excessively, problems often arise. Excessive inward rolling of the feet and ankles is called over-pronation. Sometimes, people who over-pronate are told they have ?flat feet?. The term ?flat feet? can be misleading. When standing, body weight causes the arch of most feet to flatten out somewhat. This does not mean they become flat like pancakes (though some feet do). Instead, the arch shape gets longer and flatter and the arch height gets lower.
In adults, the most common reason for the onset of Over-Pronation is a condition known as Post Tibial Tendonitis. This condition develops from repetitive stress on the main supporting tendon (Posterior Tibial Tendon) of the foot arch. As the body ages, ligaments and muscles can weaken. When this occurs the job of providing the majority of the support required by the foot arch is placed upon this tendon. Unfortunately, this tendon cannot bear the weight of this burden for too long. Eventually it fatigues under the added strain and in doing so the foot arch becomes progressively lower over a period of time.
Common conditions seen with overpronation include heel pain or plantar fasciitis. Achilles tendonopathy. Hallus Valgus and/or bunions. Patellofemoral pain syndrome. Iliotibial band pain syndrome. Low back pain. Shin splints. Stress fractures in the foot or lower leg.
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
Overpronation is a term used to describe excessive flattening of the plantar arch. Pronation is a normal part of our gait (the way we walk), and it comprises three movements: dorsiflexion, eversion, and abduction. Dorsiflexion is the upward movement of the foot, eversion describes the foot rolling in, and abduction is ?out toeing,? meaning your toes are moving away from the midline of your body. When these three motions are extreme or excessive, overpronation results. Overpronation is very common in people who have flexible flat feet. Flatfoot, or pes planus, is a condition that causes collapse of the arch during weight bearing. This flattening puts stress on the plantar fascia and the bones of the foot, resulting in pain and further breakdown.
Hyperpronation can only be properly corrected by internally stabilizing the ankle bone on the hindfoot bones. Several options are available. Extra-Osseous TaloTarsal Stabilization (EOTTS) There are two types of EOTTS procedures. Both are minimally invasive with no cutting or screwing into bone, and therefore have relatively short recovery times. Both are fully reversible should complications arise, such as intolerance to the correction or prolonged pain. However, the risks/benefits and potential candidates vary. Subtalar Arthroereisis. An implant is pushed into the foot to block the excessive motion of the ankle bone. Generally only used in pediatric patients and in combination with other procedures, such as tendon lengthening. Reported removal rates vary from 38% - 100%, depending on manufacturer. HyProCure Implant. A stent is placed into a naturally occurring space between the ankle bone and the heel bone/midfoot bone. The stent realigns the surfaces of the bones, allowing normal joint function. Generally tolerated in both pediatric and adult patients, with or without adjunct soft tissue procedures. Reported removal rates, published in scientific journals vary from 1%-6%.