Pronation is the natural act of the body spreading the impact of walking, jogging or running throughout the foot evenly. As the foot strikes the ground, the ankle naturally rolls inward absorbing the shock of the ground and mobilizing to the terrain. Overpronation is when the ankle of the foot rolls in past its normal 15? of inward rotation. The cause of this could be many things such as foot type, biomechanics, or compensation strategies. People with flat feet often, although not always, overpronate.
Unless there is a severe, acute injury, overpronation develops as a gradual biomechanical distortion. Several factors contribute to developing overpronation, including tibialis posterior weakness, ligament weakness, excess weight, pes planus (flat foot), genu valgum (knock knees), subtalar eversion, or other biomechanical distortions in the foot or ankle. Tibialis posterior weakness is one of the primary factors leading to overpronation. Pronation primarily is controlled by the architecture of the foot and eccentric activation of the tibialis posterior. If the tibialis posterior is weak, the muscle cannot adequately slow the natural pronation cycle.
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.
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
Adequate footwear can often help with conditions related to flat feet and high arches. Certified Pedorthists recommend selecting shoes featuring heel counters that make the heel of the shoe stronger to help resist or reduce excessive rearfoot motions. The heel counter is the hard piece in the back of the shoe that controls the foot?s motion from side-to-side. You can quickly test the effectiveness of a shoe?s heel counter by placing the shoe in the palm of your hand and putting your thumb in the mid-portion of the heel, trying to bend the back of the shoe. A heel counter that does not bend very much will provide superior motion control. Appropriate midsole density, the firmer the density, the more it will resist motion (important for a foot that overpronates or is pes planus), and the softer the density, the more it will shock absorb (important for a cavus foot with poor shock absorption) Wide base of support through the midfoot, to provide more support under a foot that is overpronated or the middle of the foot is collapsed inward.
Wearing the proper footwear plays a key role as a natural way to help pronation. Pronated feet need shoes that fit well, provide stability, contain supportive cushioning, are comfortable and allow enough room for your foot to move without causing pain or discomfort. Putting special inner heel wedges, known as orthotics, into your shoes can support a flatfoot while lowering risks of developing tendinitis, according to the American Academy of Orthopaedic Surgeons. More extensive cases may require specially fitted orthopaedic shoes that support the arches.