Arch support therapy treats problems

Conway McLean, DPM, Journal columnist

Although few think about it, I contemplate the subject of body mechanics frequently. It is a fascinating topic, that of body motion and body mechanics. There is much to be discovered, so much we do not yet know. Think for a moment, if you would, of the wonders of human locomotion. I have no doubt you will also be amazed at the complexity of the musculoskeletal system and how it functions.

Ask any builder: build a house on a crooked foundation and you’ll have a crooked house! The same applies to the human body. For a host of reasons, the pelvis and spine can become improperly aligned. This will generally result in all manner of possible problems, from pinched nerves, to slipped discs in the spine, to hip articulation problems, and many more. All these, and others, are possible consequences of a change in normal architecture and function of skeletal structure.

Naturally, a critical component of this discussion is one of the elemental rules of the universe: gravity. This is a constant companion in our average day, pulling every cell of our body downwards, especially denser substances like muscle and bone.

Predictably, the more weight you carry, the more stress to your base, your support system: the foot, ankle and lower leg. The impact forces during the simple act of walking average one and one-half times body weight with each and every step. Then think about the cumulative effects of ten thousand steps a day, times 365 days a year. Most of us are at least somewhat familiar with some of the consequences of aging on the human body, and these effects do accumulate.

Some are simply born with bad alignment, as opposed to spending too many years standing on hard, unforgiving surfaces. Or, perhaps, wearing bad, poorly-supportive shoe gear. For many reasons, many individuals reach a point where the arch “falls.”

Rarely does it go straight down, but instead it typically goes through a rolling motion, with the arch going inward, the front of the foot moving outward, and yes, the arch going down. (Foot motion, as a rule, occurs in three directions, almost never just one.)

Unfortunately for the human body, in the process of evolution, the lower leg became locked onto the highest foot bone, known as the talus. Another building concept comes into play here: the ankle “mortice.”

The two lower leg bones straddle this bone, and so are locked into place over it, whereby when the talus turns, so does the lower leg. Think about this for a moment. Every time the arch “falls,” the talus is turning inward. Thus, the lower leg must be as well. Likely you are familiar with the old song “the lower leg bone’s connected to the upper leg bone” (or something to that effect). In kinesthesiology, the study of body motion, this highlights the concept of the kinetic chain. Nothing in the body operates independently.

Preventing excessive amounts of this inward falling motion, what we call pronation, can be achieved with some type of support. “But what kind?” you should ask. This is a topic of some debate, so let’s debate it. Can it be a ten-dollar soft foam insole from the dollar store? Certainly, though one has to ask oneself how much will that do? Not very much is the obvious answer. How much a person has to spend to get good support for your foot mechanics is dependent on a multitude of factors. As mentioned, your body mass index is of significance. Also critically important is your ancestry, ie your genetic composition. You can pick your neighbors, but you can’t pick your family.

Some people don’t need any extra support, while others possess such terrible foot architecture and lower extremity mechanics that a multitude of problems tend to develop over the years. These people need something more than a piece of soft foam. And some generic device, intended to fit everyone, will be insufficient to keep their musculoskeletal system aligned properly. A custom, prescription arch support, technically defined as a foot orthosis, generally referred to as orthotics, are the best option for some. These can be immensely powerful, when correctly prescribed, in reducing symptoms from those joints using the foot as its support system. (Oh, but wait, that’s pretty much every joint, muscle, tendon and ligament in the body!)

The fitting of a prescription device to maintain body alignment is an extremely complex task, as perhaps you can imagine. Unfortunately, it is not always treated as such. Poorly trained, non-medical staff are often the one’s assigned the task of creating a copy of the patient’s foot, a vital part of the production of a pair of foot orthoses. Several methods are frequently used for doing this, and many are not exacting enough. Then, even worse, everyone gets the same prescription. This means the same materials, the same modifications, the same alterations to the copy they created of the person’s foot. I’ve seen this in person and it is not good medicine.

A gait exam should generally be performed to see how to optimize the individual’s mechanics. Weight-bearing x-rays are required to look at their bony architecture. Careful scrutiny of their joint function is also important. Then, to make matters even more complex, many differing theories exist about how to reduce the pain of chronically over-stressed soft tissue structures, typically the part of the body that ends up producing the sensation of pain. As you can see, this is not a simple process, although most of these steps are not utilized in the creation of your average pair of foot orthotics.

What is your typical consumer to do? How to know what is a good pre-fabricated arch support? It is an extremely challenging task, especially considering how much misinformation there is on the internet. Customer reviews can be helpful, but each must be taken with a “grain of salt”. And how to know what kind of support you personally need? Due to the complexity and challenges of prescribing a comfortable and beneficial foot orthotic, simply seeking out a health care provider who dispenses these medical devices is no assurance the prescription will provide the needed control of foot, leg and body mechanics.

Podiatric physicians were once considered the premier practitioners of orthotic therapy, but many in the profession have fallen in love with surgical options. Because many surgeries can alter lower extremity mechanical function, a thorough understanding of how the musculoskeletal system works is critical. It would seem this is not being stressed sufficiently in podiatric education, in the opinion of many in the profession. Predictably, less than optimal surgical results may be the end-product.

Foot orthoses are powerful medicine, when correctly prescribed. Yet, not everyone needs a custom device. Without insurance coverage, doing some internet research and ordering an off-the-shelf device is a common practice, and often enough. Still, a device that is made for your individual left and right foot, using the best techniques available, with an in-depth knowledge of lower extremity mechanics is not going to hurt. They may even decrease the amount of degenerative changes to many joints, over the years. I believe they call that preventative medicine; what a concept!

Editor’s note: Dr. Conway McLean is a physician practicing foot and ankle medicine in the Upper Peninsula, with an upcoming move of his Marquette office to the downtown area. McLean has lectured internationally on wound care and surgery, being double board certified in surgery, and also in wound care. He has a sub-specialty in foot-ankle orthotics. Dr. McLean welcomes questions or comments at drcmclean@outlook.com.