Over-pronation, or flat feet, is a common biomechanical problem that occurs in the walking process when a person?s arch collapses upon weight bearing. This motion can cause extreme stress or inflammation on the plantar fascia, possibly causing severe discomfort and leading to other foot problems.
During our development, the muscles, ligaments, and other soft tissue structures that hold our bones together at the joints become looser than normal. When the bones are not held tightly in place, the joints are not aligned properly, and the foot gradually turns outward at the ankle, causing the inner ankle bone to appear more prominent. The foot moves in this direction because it is the path of least resistance. It is more difficult for the foot to move in the opposite direction (this is called supination). As we develop, the muscles and ligaments accommodate to this abnormal alignment. By the time growth is complete, the pronated foot is: abnormally flexible, flat, and its outer border appears raised so that as you step down you do not come down equally across the entire foot; instead, you come down mostly on the inner border of the foot. Normal aging will produce further laxity of our muscles that causes the pronation to become gradually worse.
Because pronation is a twisting of the foot, all of the muscles and tendons which run from the leg and ankle into the foot will be twisted. In over-pronation, resulting laxity of the soft tissue structures of the foot and loosened joints cause the bones of the feet shift. When this occurs, the muscles which attach to these bones must also shift, or twist, in order to attach to these bones. The strongest and most important muscles that attach to our foot bones come from our lower leg. So, as these muscles course down the leg and across the ankle, they must twist to maintain their proper attachments in the foot. Injuries due to poor biomechanics and twisting of these muscles due to over-pronation include: shin splints, Achilles Tendonitis, generalized tendonitis, fatigue, muscle aches and pains, cramps, ankle sprains, and loss of muscular efficiency (reducing walking and running speed and endurance). Foot problems due to over-pronation include: bunions, heel spurs, plantar fasciitis, fallen and painful arches, hammer toes, and calluses.
If you have flat feet or low arches, chances are you overpronate. Although not always the case, the lower your arches the greater the overpronate. Stand on a hard surface (in front of a mirror if you need to) and look at your feet, flat feet or low arches are easy to spot. If your feet look flatter than a pancake, have a look at your ankles and see if they seem collapsed or straight. If they are, you're overpronating.
Non Surgical Treatment
Get a gait analysis of your running style, this will highlight if you overpronate, oversupinate or have a neutral gait. Most podiatrists, physio's and sports therapists will offer this service, as do some specialist sports shops. Find a clinic. If you overpronate, get orthotics with extra medial support. Many running shoes have a harder material on the inside of the midsole (the thick hard foam part of the running shoe). This means the inside of the shoe will be compressed less under load and support the inside of the foot preventing it from rolling in or flattening. For people with considerable overpronation, another option is to have an orthotic device fitted. Orthotic insoles come in many types and prices. Some are pre-molded and can be bought off the shelf. These are ok for the majority of problem feet. However some cases may require specially casted orthotics from a relevant sports injury therapist or podiatrist.
Firstly, a thorough and correct warm up will help to prepare the muscles and tendons for any activity or sport. Without a proper warm up the muscles and tendons around your feet, ankles and lower legs will be tight and stiff. There will be limited blood flow to the lower legs, which will result in a lack of oxygen and nutrients for those muscles. Click here for a detailed explanation of how, why and when to perform your warm up. Secondly, flexible muscles are extremely important in the prevention of most ankle and lower leg injuries. When muscles and tendons are flexible and supple, they are able to move and perform without being over stretched. If however, your muscles and tendons are tight and stiff, it is quite easy for those muscles and tendons to be pushed beyond their natural range of motion. To keep your muscles and tendons flexible and supple, it is important to undertake a structured stretching routine.