Foot Function by William Rossi


Dr. William Rossi

This is an extract from an article by Dr. William Rossi entitled "The Arches: Some Controversial Views", It was originally published online in the journal, Podiatry Management.


.... Consider some realities. As already cited, the prime function of the arches is to absorb body weight shock in standing, walking, or running, and to return the absorbed energy via the elastic apparatus of the arches. They serve not only to maintain body balance but to provide the spring and propulsion for the step. The foot's arches and their associated mechanisms (muscles and tendons, fascia, ligaments, and joints) are marvelously designed for these functions. It should be obvious that the more these complex spring forces are hampered or reduced or otherwise interfered with, the less effective the whole spring mechanism will be.

Yet that is precisely what happens to the average foot with any form of artificial support mechanism. Loss of elasticity with increase of rigidity is common with the feet of persons 60 years and over. This is usually ascribed to the natural "aging" process. The feet not only display anatomical and functional deficiencies, but are often accompanied by distress symptoms and diminished gait mobility. Almost all the conditions involve the foot's complex arch system.

But the "aging process" theory is highly debatable. Among shoeless people of advanced years there is rarely loss of foot elasticity or gait mobility, or presence of foot distress symptoms. Among shoe-wearing people, however, the foot has been in a constrictive caged state two-thirds of the life span. There is inevitable deterioration of the foot's spring or arch system -- much the same way as a body part held in a rigid cast for a prolonged period atrophies and loses strength. It has little to do with "aging." It has much to do with shoe-caused loss of elasticity over a long period.

Another important factor is involved. Most shoe-wearing people walk on less than half of their natural plantar tread surface. This is easily demonstrated. Dampen the sole of your foot, then place it on a paper towel. Remove your foot, then quickly draw an outline around the print. Now, examine the sole and heel of one of your worn shoes. Then compare the two soleprints. The shoe will show wear mostly at the outside-rear corner of the heel and at the center of the ball. The remaining part of the shoe bottom will show little or no wear. The worn shoe tread area will usually amount to half or less than the footprint area -- indicating that you are walking on only half of your foot.

What does it mean? The "working" half of your foot is bearing an over-load while the non-working half is unutilized -- and indicating progressive loss of strength. Why the limited shoe tread? Again, a combination of faults in shoe design and construction which negatively affect shoe tread.

A foot walking on virtually any shoe is automatically unbalanced. While an orthotic may assist in providing proper foot balance, both foot and orthotic become victim of the built-in imbalance of the shoe and hence cannot perform at full efficiency.

Common biomechanical conditions such as excessive pronation or fasciitis or tendonitis are usually treated as separate, isolated lesions. But all are linked to the arch system and cannot be separated from the failings in the foot's overall spring mechanisms.

Among shoe-wearing people there is no such thing as a fully natural or "normal" foot, either anatomically or functionally. Constantly denied its natural need and ability for constant exercise, the shoe-wearing foot has lost its capacity for normal function.

The inherent faults of shoe design and construction are intensified further by the increasing use of built-in "arch supporting" features which impose additional limitations on natural exercise functions so vital to the elastic arch system. ...