Over-pronation is very common and affects millions of Australians. To better understand this condition, we'll take a closer look at the 3 most common foot types. An estimated 70% of the population has fallen arches (or a low arch). Only 20% have a normal arch. And 10% have abnormal feet, in other words they either have flat feet or the opposite, a high arched foot. Most of us have a low arch. The foot actually appears quite normal and a clear (but low) arch is present under the foot, especially when sitting down. The situation changes with weight-bearing: when we get up the arch lowers. When we start walking the arches collapse and the ankles roll inwards. This is called over-pronation or fallen arches. Over-pronation is not the same as flat feet as often noted.
Overpronation often occurs in people with flat feet, whose plantar fascia ligament is too flexible or too long, and therefore unable to properly support the longitudinal arch of the foot. People tend to inherit the foot structure that leads to overpronation. In a normal foot the bones are arranged so that two arches are formed, the longitudinal and the transverse. Ligaments hold all the bones in their correct positions, and tendons attach muscles to bones. If the bones are held together too loosely, they will tend to move inwards as this is the easiest direction for them to go. Over time the soft tissue structures will adjust to the misalignment and the foot will become permanently over-flexible, with a flat arch.
Not all foot injuries affecting runners are necessarily down to a particular running gait; it is rarely that simple to diagnose how a foot problem developed . Simply being an overpronator does not mean that a foot injury has been caused by the running gait and it could be due to a number of factors. However mild to severe overpronators tend to be at a higher risk of developing musculoskeletal problems due to the increased stresses and strains which are placed on the body when the foot does not move in an optimum manner. The following injuries are frequently due to overpronation of the feet. Tarsal tunnel syndrome. Shin splints. Anterior compartment syndrome. Plantar fasciitis. Achilles tendonitis. Bunions. Sesamoiditis. Stress fractures. Back and hip pain. Ankle pain.
One of the easiest ways to determine if you overpronate is to look at the bottom of your shoes. Overpronation causes disproportionate wear on the inner side of the shoe. Another way to tell if you might overpronate is to have someone look at the back of your legs and feet, while you are standing. The Achilles tendon runs from the calf muscle to the heel bone, and is visible at the back of the ankle. Normally it runs in a straight line down to the heel. An indication of overpronation is if the tendon is angled to the outside of the foot, and the bone on the inner ankle appears to be more prominent than the outer anklebone. There might also be a bulge visible on the inside of the foot when standing normally. A third home diagnostic test is called the ?wet test?. Wet your foot and stand on a surface that will show an imprint, such as construction paper, or a sidewalk. You overpronate if the imprint shows a complete impression of your foot (as opposed to there being a space where your arch did not touch the ground).
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.
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.