Pronation is the normal movement the foot makes to absorb the impact from walking or running. It occurs once the heel strikes the ground and the foot disperses the impact, stretching and flattening the arch as the foot rolls inward. Supination is the opposite motion of pronation. The foot supinates, or rolls on its outer edge, to help with stability as we walk or run. A reasonable amount of pronation is necessary for the foot to function properly. However, when the foot arch remains flat and the foot rolls inward too much one may have excessive pronation or overpronation. This medical condition can result from continually straining the feet and wearing footwear that lacks sufficient foot arch support.
Pronation can occur as an overuse syndrome in active runners, where a great deal of stress is placed on ligaments and tendons that support the medial column. Obesity is another predictor for pronation and deterioration of the medial ligaments and posterior tibial tendon due to excessive stress on these tissues. Acute Trauma can also lead to over-pronation when ligaments are torn or tendon is ruptured. Once again this can lead to a collapse of the medial column. Arthritic conditions involving the knee joint when the joint is in varus (inner collapse) posture, this places the center of gravity over the ankle joint rather than the foot causing undue pressure on the inner ankle.
Overpronation causes alterations in proper muscle recruitment patterns leading to tightness in the outside of the ankle (lateral gastrocnemius, soleus, and peroneals). This tightness can lead to weakness in the opposing muscles such as the medial gastrocnemius, anterior tibialis, and posterior tibialis. If these muscles are weak, they will not be able to keep the knee in proper alignment, causing the valgus position. All this tightness and weakness can cause pain within the ankle, calf, and knee region. And it can send imbalance and pain all the way up to the upper back, if deep core strength is lacking and can't hold the pelvis in neutral.
Your healthcare provider will ask about your symptoms, medical history, and activities and examine your feet. Your provider may watch you walk or run. Check the motion of your feet when they strike the ground. Look at your athletic shoes to see if they show an abnormal pattern of wear.
Non Surgical Treatment
Your podiatrist will look at your current footwear to ensure that it is both well-fitted and possessed of adequate cushioning to protect your feet. Firm heel support is advised for over-pronators, and a good fit is important to ensure that the foot as a whole is well supported as instability can exacerbate the existing problems caused by over-pronation.
Hyperpronation can only be properly corrected by internally stabilizing the ankle bone on the hindfoot bones. Several options are available. Extra-Osseous TaloTarsal Stabilization (EOTTS) There are two types of EOTTS procedures. Both are minimally invasive with no cutting or screwing into bone, and therefore have relatively short recovery times. Both are fully reversible should complications arise, such as intolerance to the correction or prolonged pain. However, the risks/benefits and potential candidates vary. Subtalar Arthroereisis. An implant is pushed into the foot to block the excessive motion of the ankle bone. Generally only used in pediatric patients and in combination with other procedures, such as tendon lengthening. Reported removal rates vary from 38% - 100%, depending on manufacturer. HyProCure Implant. A stent is placed into a naturally occurring space between the ankle bone and the heel bone/midfoot bone. The stent realigns the surfaces of the bones, allowing normal joint function. Generally tolerated in both pediatric and adult patients, with or without adjunct soft tissue procedures. Reported removal rates, published in scientific journals vary from 1%-6%.