Pronation, in anatomical terms, means to rotate, and it applies to any rotational movement of a bone. Pronation in the feet involves an inward rolling of the foot throughout the gait which helps with the transfer of force. Normally the foot will move from the heel to the toes with only a small degree of pronation, with a slight inward roll from the outside of the heel to the inside of the foot which helps to support the body weight. Normal pronation involves the rolling of the foot to approximately 15 degrees. If you have normal foot arches, you are likely to be a neutral runner and will most likely pronate normally.
Over-pronation is very prominent in people who have flexible, flat feet. The framework of the foot begins to collapse, causing the foot to flatten and adding stress to other parts of the foot. As a result, over-pronation, often leads to Plantar Fasciitis, Heel Spurs, Metatarsalgia, Post-tib Tendonitis and/or Bunions. There are many causes of flat feet. Obesity, pregnancy or repetitive pounding on a hard surface can weaken the arch leading to over-pronation. Often people with flat feet do not experience discomfort immediately, and some never suffer from any discomfort at all. However, when symptoms develop and become painful, walking becomes awkward and causes increased strain on the feet and calves.
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.
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
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.
Subtalar Arthroereisis. Primary benefit is that yje surgery is minimally invasive and fully reversible. the primary risk is a high chance of device displacement, generally not tolerated in adults.
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.