What is pronation?
Pronation may very well be the most overused and misunderstood term in foot biomechanics. Severe pronation can be seen when someone walks on the insides of their feet. The inner soles of the shoes wear out quickly. Mild and moderate pronation are not easily identified by simply watching someone walk or looking at shoe wear.
The foot is capable of undergoing 2 basic motions – one of which is pronation. Pronation is a complicated joint motion involving movement of several joints in several different planes. The motion results in a dropping of the arch or a “falling” to the inside. Often the legs, knees and hips fall in with the feet. Pronation is not always easily recognized simply by watching someone walk or by looking at the wear on the bottom of their shoes. If only it were that simple. Often flat footedness is confused with pronation. Someone who has “flat feet” will generally look very pronated (arches are flat on the ground). The two are not synonymous. Also, high arched feet (which look supinated or tilted to the outside) are often quite pronated in walking gait.
What causes excess pronation?
The list is long…usually there is some degree of hypermobility in the foot, i.e. the ligaments are loose and the joints are allowed to undergo more range of motion than they need to. In some sports, hypermobility (hyper flexibility) is considered to be an advantage. Not true with feet – the feet need mobility (in order to absorb shock), not hypermobility – which makes it difficult for the foot to stabilize properly. Other contributing factors include: abducted (turned out) or adducted (turned in) gait pattern; tight achilles tendons; inturned knees or hips; chronic pain anywhere in the lower extremity; leg length discrepancy; loss of muscle function after a stroke or nerve injury; cerebral palsy or other spastic disorder; bunions and hypermobile forefoot joints; worn-out shoes; being overweight; high-impact activities such as long distance running-–I could go on but as you can see, there are many factors involved.
What does excess pronation cause?
Interesting question and important to consider. If someone is excessively pronated does that necessitate treatment-–generally speaking not unless the pronation is causing a symptom or creating a situation that will clearly lead to symptoms in the future. The excess motion of the foot joints caused by pronation and extra work placed on the muscles, as a result leads to a gigantuous list of potential problems. The most common are: bunions, heel pain, hammertoes, medial tibial stress syndrome (shin splints), achilles tendonitis, knee pain, back pain, general fatigue in the lower extremities, ingrown toenails, neuromas, and I’ll stop there. Remember this though: many pronation-related problems can also be caused by things other than excess pronation. Just because someone has bunions and is pronated doesn’t mean the two are related. This makes treating lower extremity symptoms rather complicated. Identifying all contributing factors in a lower extremity problem (other than pronation) will improve the chances that the chosen treatment will work.
How is excess pronation treated?
We’ll touch on this here. If the problem is hypermobile foot joints, the logical solution would be to find a way to decrease the mobility of these joints. The most effective approach (in my opinion) is using custom orthotics and shoe change. Start with shoe change. Runners, hikers and good quality athletic walking shoes are the most supportive. Lace-up shoes are better than slip-ons. Closed backs are generally better than open backs.
Most of the pronation control in a shoe comes from the heel counter and the denseness of the sole material on the inside of the shoe. The arch support inside generally provides negligible support. Shoes should be replaced much more frequently than most people realize. A good walker or runner lasts 3 to 6 months for the serious runner, 6 to 12 months for the average runner, and 12 to 24 months for the average walker. If shoe change doesn’t help, consider the option of custom orthotics. This can be a daunting task. Who should you see, who can you trust, how do you get the best possible orthotic? The bottom line – see a professional and use your intuition. Find people who have experience, expertise and aren’t in a hurry to rush you out of the office with an orthotic prescription.