Overpronation and underpronation describe general foot movements. These terms do not necessarily describe a medical problem with a foot. For example, you can overpronate and not have any problems or symptoms at all. It is important to have your foot structure and symptoms adequately assessed by your prescribing physician and a qualified practitioner such as a Canadian Certified Pedorthist. Once the underlying conditions and mechanical faults are assessed, an appropriate treatment plan including possible orthotic and footwear recommendations can be made.
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 can lead to injuries and pain in the foot, ankle, knee, or hip. Overpronation puts extra stress on all the bones in the feet. The repeated stress on the knees, shins, thighs, and pelvis puts additional stress on the muscles, tendons, and ligaments of the lower leg. This can put the knee, hip, and back out of alignment, and it can become very painful.
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
Not all over pronation is treated. Although, when it appears to be a causitive factor that is contributing to pain,or development of structural deformities, there are various degrees of treatment.In some cases specific shoes may be all that is required. In other cases, paddings or strapping, are prescribed and where necessary orthotic therapy. A podiatric assesment would be advised to asses this.
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%.