While a slight amount of pronation is the proper means to absorb shock naturally, too much pronation (over-pronation) can potentially contribute to many maladies, which can sideline a runner. A foot that pronates excessively is one that continues to roll inward past a neutral position after the shock of impact has been absorbed. Uncorrected and repeated, this motion may lead to repetitive stress related injuries of the feet and legs. More times than not, the runner who over-pronates needs a shoe that reduces excess pronation and guides the foot along a neutral path.
There is a relationship between biomechanics and injury that is specific to each body part. Overall though, poor mechanics will either increase the landing forces acting on the body or increase the work to be done by the muscles. Both increase the stress, which, depending on the individual and the amount of running can become excessive and cause injury.
When standing, your heels lean inward. When standing, one or both of your knee caps turn inward. Conditions such as a flat feet or bunions may occur. You develop knee pain when you are active or involved in athletics. The knee pain slowly goes away when you rest. You abnormally wear out the soles and heels of your shoes very quickly.
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.
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.