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A recent New York Times article about orthotics and flat feet recounted the experience of Jason Stillman, a man with flat feet that virtually every medical doctor he has ever seen has tried to treat. Starting in puberty, Stillman was given orthotics to wear all the time. (1)

According to the Mayo Clinic, an individual has flat feet when the arches on the insides of the feet are flattened, allowing the entire soles to touch the floor when standing up. (2) In searching for definitions, this seems to be a fairly common one.

If you have read the first two installments in this series, you probably know by now that I am fairly enamored with Dr. Hoffman’s study of hundreds of pairs of feet in which he compared shoe wearers to life-long barefooters. (3)  In 1905, Dr. Hoffman called into question some of same issues that have been all over the news for the past few years.

In his findings, Hoffman concluded that while low arches (a decreased longitudinal arch) is less common than a medium arch (follow link to see the bones of the foot and a medium arch), it has no bearing on the common diagnosis of “flat foot”.  Stillman, the man who started wearing orthotics in puberty might agree since he has now weaned himself almost entirely from orthotics and uses them only when running.

“Observations on the longitudinal arch of the foot led to the conclusion, contrary to common opinion and teaching, that its height and shape are of little or no value in estimating the usefulness of the foot, and that there is no one type as the normal, but that normal feet present high, medium and low arches. While it is true that the moderately high arch is in preponderance, the very low arch, when present, seems to be no indication of weakness, and in many instances where it was found in the primitive Filipino or African, it was associated with a foot that was strong and flexible.” 

He goes on to say that the so called flat foot diagnosis is not dependent on a low arch but “whether there was a transition from an original higher condition with concomitant change in the relationship of the tarsal bones and strain of ligaments and muscles.”  He felt such a transition was rare.

“It is not uncommon to find the same symptoms associated with arches of good height and I have found them associated with an extraordinarily high arch. It is equally as common to find low arches in symptomless feet.”

Arched, flat and flexible - What?!

As you can see in the illustration based on Dr. Hoffman's research, an adult Bagobo, who had never worn shoes, did have flat feet. 

Dr. Benno Nigg, a professor of biomechanics and co-director of the Human Performance Lab at the University of Calgary in Alberta, has always wondered what the big deal about flat feet is.  He views foot arches as an evolutionary remnant for gripping trees. However, study of the hominin foot from the Plio-Pleistocence period suggests that even then there was a great deal of variation in arch development. "Lucy" in particular had flat feet. (4) Research just published last month by Carol Ward and colleagues confirms that Lucy and her kin had a stiff mid-foot that allowed for extensive walking but was not as good as the flexible mid-foot apes use for branch grabbing. (5)

Today's human foot is an interesting combination of stiffness and flexibility. The stiffness gives us a lever for pushing against the ground, the flexibility provides the shock absorption.

Propulsion and Shock Abortion

Developments in artificial limbs has highlighted the importance of ligaments and tendons as springs for motion against gravity. Springs have the interesting quality of storing energy and delivering explosive power. Prosthetic limb researcher Hugh Herr has done some leading-edge exploration along these lines using his own body as the laboratory. Herr lost his legs below the knee at age 17. Since then he has systematically worked to bring himself back to normal function. At MIT, he has honed in on the important role of tendons and their spring-like fibers. "The body uses springs to reduce the work the muscles have to do. The human leg is filled with them, and there is this elaborate energetic flow. Energy is constantly being shuffled from tendon to tendon to tendon." (2)

Herr has been using motors to feed energy into springs so that the spring can release pent-up energy at once, allowing the prosthetic foot to propel off the ground like a normal human foot. Herr is himself now running up to four miles a day using his own technology.

Of course, all these spring-like tendons work together. They are continually sending information up the spinal cord to the brain, and the brain is sending instructions back down. All along the chain, an intricate coordinated response is being formulated moment to moment.

How does this relate to flat feet? As Dr. Nigg in 2011 indicates, and as Dr. Hoffman wrote in 1905, flat feet are not necessarily a problem.

An Integral Human Gait™ View

From our Integral Human Gait™ theory perspective, the "flat foot" is a bit misleading. A low arch does not inhibit the springs on the tendons of the lower extremity from working efficiently. I have seen a number of clients with high arches whose tendons have lost their spring.

From a somatic perspective, the image we have of our body matters. If you would like to improve your walk, try thinking of your feet and lower legs as containing springs. Simply shifting your idea can make a huge difference. For the therapist or somatic educator working with a person who has lost the spring in the longitudinal arch of the foot, try playing with dynamic alignment (not static) and engage the client in press/release motions along the entire chain, or at least the chain of the foot to the gluteal muscles.  Include in your thoughts and plans for improvement not only the muscles and tendons but the bony arch of the foot through the tibia, fibula, and even how the head of the femur seats itself in the hip socket, noting its response to pressure or availability of response to a downward force.

Supporting a flat foot with a hard arch support is likely to have the effect of further solidifying the image that the arch is rigid and instead of flexible and responsive.

There is a classic Feldenkrais® Awareness Through Movement® lesson that can be used to awaken the flexible arch of the foot.  We have made an abbreviated version available MP3 audio available at no charge: Mapping The Arch of the Foot.  It is one of the key exercises we use in our Gait for Wild Human Potential workshop. Take a listen. You will likely be surprised at by the lesson.

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Cynthia Allen is a Feldenkrais® Practitioner and Bones for Life® Teacher/Trainer. She is co-creator of the Integral Human Gait™ Theory and teacher of Gait for Wild Human Potential workshops. 

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 References

(1) Kolata, G. (2011, January 18). Close Look at Orthotics Raises a Welter of Doubts, The New York Times, p. D5.

 (2) Mayo Clinic Staff (2010). Flatfeet. Retrieved from http://www.mayoclinic.com/health/flatfeet/DS00449 accessed 2/06/11

(3)  Hoffman, P. (1905). Conclusions drawn from a comparative study of the feet of barefooted and shoe-wearing peoples, The Journal of Bone and Joint Surgery, 2 (3), 105-136.

(4) DeSilva, J. M., & Throckmorton, Z. J. (2010). Lucy's Flat Feet: The Relationship between the Ankle and Rearfoot Arching in Early Hominins, PLoS ONE 5 (12). Retrieved from http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0014432

(5) University of Missouri-Columbia (2011, February 10). Foot bone suggests Lucy’s kin had arched foot, for walking. ScienceDaily. Retrieved February 20, 2011, from http://www.sciencedaily.com­ /releases/2011/02/110210141213.htm

 (6) Piore, A. (2010, November) The Bionic Man, Discover,31(9), 52-57