Overpronation of the foot is not an injury itself but if you overpronate then you may be more susceptible to a number of sports injuries. It is often recognised as a flattening or rolling in of the foot but it is not quite as simple as that as the timing of when the foot rolls in is also important.
What is overpronation of the foot?
Pronation occurs as weight is transferred from the heel to the forefoot when walking or running and the foot naturally rolls inwards. A certain amount of this is natural but in many people the foot rolls in too much or overpronates.
When standing, pronation occurs as the foot rolls inwards and the arch of the foot flattens, hence the term often used to describe someone who overpronates as having 'flat feet'. Pronation is a normal part of the gait cycle which helps to provide shock absorption at the foot. The opposite movement to pronation is supination.
How does overpronation cause Injury?
Excess pronation usually causes overuse type injuries, occurring most frequently in runners. When a neutral foot pronates during walking or running, the lower leg, knee and thigh all rotate internally (medially). When an athlete with an overpronates this rotation inwards movement is exaggerated. This in turn increases the stresses on the muscles, tendons and ligaments of the foot, lower leg including shin and knee as the limb rotates in too far.
How can I tell if I overpronate?
Firstly, look at your feet in standing, have you got a clear arch on the inside of the foot? If there is not an arch and the innermost part of the sole touches the floor, then your feet are overpronated. Secondly, look at your running shoes. If they are worn on the inside of the sole in particular, then pronation may be a problem for you.
Thirdly, try the wet foot test. Wet your feet and walk along a section of paving and look at the footprints you leave. A normal foot will leave a print of the heel, connected to the forefoot by a strip approximately half the width of the foot on the outside of the sole. If your feet are pronated there may be little distinction between the rear and forefoot, shown opposite.
The best way to determine if you overpronate is to visit a podiatrist or similar who can do a full gait analysis on a treadmill or using force plates measuring exactly the forces and angles of the foot whilst running. It is not only the amount of overpronation which is important but the timing of it during the gait cycle as well that needs to be assessed.
Overpronation and running injuries
The problem with pronation is when it is excessive, here the term overpronation (or hyper-pronation) is used. This is quite a common problem and can lead to a number of injuries, especially in runners, including:
- Shin splints
- Anterior compartment syndrome
- Patellofemoral pain syndrome
- Plantar fasciitis
- Tarsal tunnel syndrome
- Bunions (Hallux valgus)
- Achilles tendonitis
The picture at the top of the page shows someone who overpronates. The right foot is rolling in. This causes the lower leg to turn inwards which puts the knee and hip out of alignment and can cause the back to be rotated.
The left foot is corrected with an orthotic device. This is inserted into the running shoe and controls the position of the heel allowing the rest of the foot to fall into place.
Get a gait analysis of your running style, this will highlight if you overpronate, oversupinate or have a neutral gait. Most podiatrists, physios and sports therapists will offer this service, as do some specialist sports shops.
If you overpronate, get a shoe 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.