Over-Pronation

Overview

Over-pronation describes a characteristic gait wherein a lack of sufficient support from the arch of the foot causes it to roll inwards as weight is placed on it. The long arch of the foot is actually a very important structure in terms of our gait and how we walk, it is responsible for ensuring that as our weight rolls from the heel to the balls of our feet it does so in a straight line that doesn?t place undue stress on the ankle or knees. Unfortunately when a person?s arch is not pronounced enough, or even simply not there (a condition called flat footedness), there isn?t enough arch support to maintain a healthy, forward motion of the foot.Overpronation

Causes

There are many possible causes for overpronation, but researchers have not yet determined one underlying cause. Hintermann states, Compensatory overpronation may occur for anatomical reasons, such as a tibia vara of 10 degrees or more, forefoot varus, leg length discrepancy, ligamentous laxity, or because of muscular weakness or tightness in the gastrocnemius and soleus muscles. Pronation can be influenced by sources outside of the body as well. Shoes have been shown to significantly influence pronation. Hintermann states that the same person can have different amounts of pronation just by using different running shoes. It is easily possible that the maximal ankle joint eversion movement is 31 degrees for one and 12 degrees for another running shoe.

Symptoms

In addition to problems overpronation causes in the feet, it can also create issues in the calf muscles and lower legs. The calf muscles, which attach to the heel via the Achilles tendon, can become twisted and irritated as a result of the heel rolling excessively toward the midline of the body. Over time this can lead to inflexibility of the calf muscles and the Achilles tendon, which will likely lead to another common problem in the foot and ankle complex, the inability to dorsiflex. As such, overpronation is intrinsically linked to the inability to dorsiflex.

Diagnosis

To easily get an idea of whether a person overpronates, look at the position and condition of certain structures in the feet and ankles when he/she stands still. When performing weight-bearing activities like walking or running, muscles and other soft tissue structures work to control gravity’s effect and ground reaction forces to the joints. If the muscles of the leg, pelvis, and feet are working correctly, then the joints in these areas such as the knees, hips, and ankles will experience less stress. However, if the muscles and other soft tissues are not working efficiently, then structural changes and clues in the feet are visible and indicate habitual overpronation.Over Pronation

Non Surgical Treatment

Orthotics are medical devices used to provide support to correct a physical abnormality. They can provide arch support when needed to remedy over-pronation, and in this particular cases the orthoses used are usually convenient shoe inserts. These can be taken in and out of shoes, and will be carefully tailored by your podiatrist to the specifics of your foot. It can take some weeks before the effects of the inserts can become truly noticeable, and in many cases your podiatrist will want to review your orthotics within a few weeks to make fine adjustments based on how well they have worked to reduce your pain.

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.