Over Pronation (Flat Feet) refers to the biomechanical shock-absorbing motion of the ankle, foot and lower leg. It is the natural inward flexing motion of the lower leg and ankle. Standing, walking, and running cause the ankle joint to pronate which in turn helps the body to absorb shock and allows it to control balance. An ankle joint that is too flexible causes more pronation than desired. This common condition is called Over- Pronation (sometimes referred to as "Flat Feet"). This foot condition places an extreme degree of strain on various connective tissues of the ankle, foot, and knee. If this condition is not addressed foot pain and toe deformities such as bunions and hammer toes (just to name a couple) may develop. Hip and lower back pain may also be residual results from this condition.
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 may have secondary effects on the lower legs, such as increased rotation of the tibia, which may result in lower leg or knee problems. Overpronation is usually associated with many overuse injuries in running including medial tibial stress syndrome, or shin splints, and knee pain Individuals with injuries typically have pronation movement that is about two to four degrees greater than that of those with no injuries. Between 40% and 50% of runners who overpronate do not have overuse injuries. This suggests that although pronation may have an effect on certain injuries, it is not the only factor influencing their development.
When sitting, an over-pronating foot appears quite normal, i.e. showing a normal arch with room under the underside of the foot. The moment you get up and put weight on your feet the situation changes: the arches lower and the ankle slightly turns inwards. When you walk or run more weight is placed on the feet compared to standing and over-pronation will become more evident. When walking barefoot on tiles or timber floors over-pronation is more visible, compared to walking on carpet or grass.
Non Surgical Treatment
Fortunately, there are simple things you can do to cure and correct your overpronation issues. Certain exercises help. Pull your toes back using a rolled up towel. Roll your feet over a golf or tennis ball for a minute. And do calf raises by standing up and lifting up on your toes. These all help reposition the foot and strengthen the muscles and tendons necessary for proper support. Beyond that, simple adjustments to footwear will help immensely.
Subtalar Arthroereisis. The ankle and hindfoot bones/midfoot bones around the joint are fused, locking the bones in place and preventing all joint motion. This may also be done in combination with fusion at other joints. This is a very aggressive option usually reserved for extreme cases where no joint flexibility is present and/or the patient has severe arthritic changes in the joint.