Niesha Bleichner

Foot Difficulties Explained

What Causes Overpronation

Overview

To understand "overpronation" it's important to first understand pronation. Pronation is a normal function of the foot. It is the inward motion of the ankle bone and outward motion of the rest of the foot bones, which occurs naturally when the foot hits the ground and weight is applied. Pronation is a good thing; it cushions the foot and the entire body during the walking cycle. It keeps the foot and ankles protected from hard impact and an uneven ground surface. Overpronation occurs when too much pronation is present. In other words, overpronation occurs when the inward motion of the ankle bone is excessive and goes past the healthy point necessary for its intended functions. This excessive motion is caused by a misalignment between the ankle bone and the hindfoot bones. It creates an imbalance of forces and weight distribution in the foot that propagates throughout the entire body. Over time, this functional imbalance causes repetitive damage to joints, ligaments and bone structures. Left untreated, overpronation can lead to foot ailments such as bunions, heel pain (plantar faciitis), hammertoes, etc. Furthermore, the excessive motion in the foot can travel up the body and cause knee, hip and lower back pain.Pronation

Causes

Flat feet don't automatically mean you have a problem. The problem can be divided into a flexible flat foot or rigid flat foot. The rigid flat foot is one that does not change shape when the foot becomes weight bearing. i.e. it does not go through the excessive motion of pronation. Generally speaking this foot does not provide too many problems. The flexible flat foot is the type that when it becomes weight bearing the foot and ankle tends to roll in (pronates) too far. This type of person will often say I have great arches but when I stand up much of this arch disappears as the foot excessively pronates When the foot is excessively pronating and causing problems like sore ankles, feet or knees when standing or exercising then arch support is extremely important to restore the foot structure.

Symptoms

Overpronation can be a contributing factor in other lower extremity disorders, such as foot pain, plantar fasciitis, ankle injuries, medial tibial stress syndrome (shin splints), periostitis, stress fractures and myofascial trigger points. Overpronation increases the degree of internal tibial rotation, thereby contributing to various knee disorders such as meniscal injury or ligament sprains. The effects of the postural deviation are exaggerated in athletes due to the increase in foot strikes while running and the greater impact load experienced. When running, three to four times the body weight is experienced with each foot strike.2 If overpronation exists, the shock force is not adequately absorbed by the foot and is transmitted further up the kinetic chain.

Diagnosis

People who overpronate have flat feet or collapsed arches. You can tell whether you overpronate by wetting your feet and standing on a dry, flat surface. If your footprint looks complete, you probably overpronate. Another way to determine whether you have this condition is to simply look at your feet when you stand. If there is no arch on the innermost part of your sole, and it touches the floor, you likely overpronate. The only way to truly know for sure, however, is to be properly diagnosed by a foot and ankle specialist.Over-Pronation

Non Surgical Treatment

Over-Pronation can be treated conservatively (non-surgical treatments) with over-the-counter orthotics. These orthotics should be designed with appropriate arch support and medial rearfoot posting to prevent the over-pronation. Footwear should also be examined to ensure there is a proper fit. Footwear with a firm heel counter is often recommended for extra support and stability. Improperly fitting footwear can lead to additional foot problems.

Surgical Treatment

The MBA implant is small titanium device that is inserted surgically into a small opening between the bones in the hind-mid foot: the talus (ankle bone) and the calcaneus (heel bone). The implant was developed to help restore the arch by acting as a mechanical block that prevents the foot from rolling-in (pronation). In the medical literature, the success rate for relief of pain is about 65-70%. Unfortunately, about 40% of people require surgical removal of the implant due to pain.