FOOT AND ANKLE

Custom Molded Orthotics

Foot pain is one of the most common causes of patients seeking medical attention. It is not a wonder in that this complex structure of 26 bones and their corresponding joints take at least a million steps a year. In our society, much of this is done on hard surfaces.

The subject of orthotics is complex but we will try to give some basic principles and illustrations to give you an appreciation of their benefit. First of all, orthotics can be prefabricated (such as the Dr. Scholl's products) or custom molded. The prefabricated (off the shelf) device gives added shock absorption but fails to control excessive motion and breaks down rather quickly. They are cheaper but tend to loose their benefit within 2 to 3 months versus custom orthotics that can last up to 2 years.

Custom molded orthotics are made specifically for each individual patient's foot. They can be done with plaster molds, standing foot impressions, and most recently with the use of a computer. At Seattle Orthopedics we have gone to the use of the computerized foot analysis. This has the advantage of looking at the dynamics of the foot through the whole gait cycle while walking. All methods prior to this have taken a static mold. Plaster molds, for instance, are usually done with the patient sitting and therefore are very limited in their accuracy of representing what forces actually go on while walking.

Orthotics achieve foot comfort by changing the way forces act on the foot. If we look at two different foot types the benefits become quite clear. In the flatfoot, there is a great deal of motion and some collapse of the arch with each step. This creates fatigue of the soft tissue structures and makes flatfooted individuals prone to conditions like tendonitis. Orthotics help to control motion and collapse in these patients. Individuals with a high arch foot usually have a much more rigid foot structure but have limited contact with the ground. This creates areas of pinpoint pressure and the entire body weight is distributed through a relatively small part of the entire surface area of the foot. Consequently, a patient with a high arch is going to be prone to calluses, pressure points, and even stress fractures in an impact exercise program. Orthotics help these people by distributing body weight through a greater surface area and decreasing the shear stress (sliding in the shoe) of the foot.