Pronation is a normal motion that our feet make as they walk. With each step, the heel touches the ground first, then the foot rolls forward to the toes, causing the ankle to roll inward slightly and the arch to flatten out. That?s normal. But when that rolling inward becomes more pronounced, that?s over-pronation, which is a big problem. You can usually see over-pronation by looking at the back of the leg and foot. The Achilles tendon normally runs straight down from the leg to the foot, hitting the floor at a perpendicular angle. In feet that over-pronate, the Achilles tendon will be at a slight angle to the ground and the ankle bone will appear more prominent than usual.
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.
Symptoms can manifest in many different ways. The associated conditions depend on the individual lifestyle of each patient. Here is a list of some of the conditions associated with Over Pronation. Hallux Abducto Valgus (bunions). Hallux Rigidus (stiff 1st toe). Arch Pain. Heel Pain (plantar fascitis). Metatarsalgia (ball of the foot pain). Ankle sprains. Shin Splints. Achilles Tendonitis. Osteochondrosis. Knee Pain. Corns & Calluses. Flat Feet. Hammer Toes.
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
Wear shoes with straight or semicurved lasts. Motion-control or stability shoes with firm, multidensity midsoles and external control features that limit pronation are best. Over-the-counter orthotics or arch supports can help, too. You know you are making improvements when the wear pattern on your shoes becomes more normal. Overpronation causes extra stress and tightness to the muscles, so do a little extra stretching.
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%.