Many variations when prescribing foot supports

Dr. Conway McLean, Journal columnist

Modern medicine has developed tunnel vision. To put it another way, specialists specialize. This system has developed by necessity since the amount of knowledge about the human body is vast and complex. But this has led to a very narrowed focus on one particular region or tissue type, making it easy to lose sight of all the other parts that effect our particular specialty. We must never lose sight of the interconnectedness of the human body and especially the musculoskeletal system.

A relatively common treatment recommendation is for some type of in-shoe support. Sounds deceptively simple, but, be assured, it is not. A simple google search will reveal a tremendous variety and variability in the supposed medical uses and benefits of foot supports. What makes up a good arch support and how is that different than a prescription support, termed a foot orthotic? Since we have wandered onto the topic, what exactly are foot orthotics and what do they do? Contrary to the opinion of the general populous, a prescription support can do so much more than simply support the arch.

For example, what if the ball of the foot is tilted slightly inward, a common finding. When body weight is placed onto the front of the foot during ambulation, the arch will lower excessively to allow this to happen. Step after step, day after day, a host of problems may develop, from heel pain to shin splints. But an over-the-counter device won’t be customized to provide this specialized support to that area. Truth be told, many providers who dispense customized foot orthotics don’t evaluate the foot for this kind of minutia, these important details, when evaluating someone for an orthotic prescription.

Thus, we have arrived at one of the most significant problems associated with foot orthotic therapy: the inconsistency. There are so many differences in how they are prescribed and what they can do for a person medically, orthopedically, biomechanically. The procedure for creating a foot orthotic typically starts with creating a copy of the foot. Yet many techniques and technologies exist for this component of the process, with some of them being faster than others, others more convenient.

For a therapy which can profoundly affect someone’s quality of life, over the course of a lifetime, convenience seems to me to be of minimal importance. Certainly, creating an efficient system for the delivery of a pair of effective and comfortable foot orthotics is important, but this critically important step requires perfection, or as close as it is possible to get. High-tech, three dimensional scanners have flooded the market because of their ease of use and convenience. But because they are not as precise as old-fashioned plaster, I personally can’t justify their use. Accuracy, precision and reliability are key to this part of orthotic prescribing.

There are many other critical components of the process. X-rays taken with the person standing provide the practitioner with vital information about their skeletal structure and mechanical function. Watching how someone walks, called a gait exam, can uncover essential data about the person’s biomechanics. Additionally, measuring the relationships of the different parts and regions of the foot and leg, like how the ball of the foot is positioned relative to the heel, is vitally important, yet often goes unevaluated. Having been in practice for years, I have had the opportunity to see, first-hand, how other physicians prescribe these. Often these critical steps are simply ignored.

This variability in how well a custom device functions explains why some insurances do not include foot orthotics as one of their benefits. When some custom foot supports are no better than something found on a rack at the shoe store, why would a health insurer make this a covered benefit? If studies cannot prove the worthiness medically of the technique, it will not be approved. Therein lies the problem with prescription foot orthoses: every practitioner dispenses a different foot orthotic, with different methods of casting, different materials, relying on differing principles. The results vary as much as the practitioners recommending them.

Good studies require large numbers of study participants. And that likely means various prescribers with their diverse methods and results. Simply because a scan or cast of the foot is made, it does not mean the support will be comfortable and, even more importantly, beneficial. Studying orthotics is like performing research on mammalian behavior and including in the study chimps, squirrels and dolphins. It’s hard to draw accurate conclusions when there are a plethora of variables. As a generalization, the fewer the variables, the better the study.

Prescribing a well-functioning foot orthotic requires a detailed knowledge of the anatomy. This is an extremely complex topic, but how all these parts work together, how they function as a unit to support us and move us through space, these are topics about which we have much yet to learn. Many experts would consider it accurate to say a majority of the pain experienced in the foot or leg started out as a biomechanical issue. Although there are a multitude of methods for dealing with inflammatory pain, from anti-inflammatory meds, to injectable steroids, to electrical stimulation (a type of physical therapy), they are not treating the root of the problem. Pain relief is a wonderful thing, no question about it, but so often the benefits are transient and impermanent, with recurrence of pain inevitable.

For example, let’s look at back pain. Granted, there are a plethora of reasons an individual may develop this common condition, but it is well recognized by specialists in body mechanics that back pain is often the result of a misaligned foundation. A collapsing arch often produces excessive rotation of the lower leg, which necessarily means the thigh rotates. This puts increased mechanical stress on the pelvis and back. We treat this, typically either with an injection or physical therapy, thus reducing inflammation and pain. This frequently helps, but why did the inflammation develop? This is a critically important question. Perhaps your back pain is due to a problem with the structures supporting the area and how they are positioned when walking, a very dynamic process.

Another consequence of this unpredictability is determining whether a prior pair of orthotics rules out the recommendation of a new prescription. When a patient presents with some painful condition for which they have previously been treated with orthotics, does it mean that this is no longer a helpful option for them? As you may have determined from this discussion, the answer is often decidedly ‘No’. Unfortunately, this makes it difficult for the average health care consumer to know.

So many painful conditions develop as a result of the harmful forces of gravity, when some bony structure is not shaped right, or is not in an optimal position. Its like driving a car with a slightly bent axle. The vehicle may continue to drive for many miles, but eventually something is going to wear out and break. How to know whether foot orthotics may benefit you? Certainly trying an off-the-shelf device is an option, and if it helps a little, it’s likely a custom device will help more.

Remember, the average person takes about ten thousand steps a day. Poor body mechanics can result in stress to soft tissue or bone structures, leading in time to inflammation and pain. It is possible, although not particularly easy, to improve musculoskeletal function. This can sometimes be achieved by simply placing a properly prescribed, customized, accurate support inside your shoe. Sounds simple, doesn’t it? As hopefully you are now aware, prescribing effective, comfortable foot orthotics is anything but.

Editor’s note: Dr. Conway McLean is a physician practicing foot and ankle medicine in the Upper Peninsula, with a 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.