Orthotic Arch Support Inserts: How They Work

"I am pleased to say that after [my mother] received her custom made arch supports, she has not had any physical discomforts and not one headache since December, 2004" -L.H.

The orthotics produced by Florida BioMechanics Group are distinctly unique in the world of orthotics.

Once upon a time, modern foot orthotics were known as arch supports.

To understand how orthotic arch supports work, you have to understand how the arch works. When the foot comes down on the ground, the arch flattens. This “flattening” motion is what cushions the impact which would otherwise become quite the destructive force – given each foot has to alternately support your entire weight when you are walking and three to five times your weight (due to impact forces) when you are running.

If the arch isn’t strong enough to support your full weight during activity, the arch ends up completely flattening out to the end of its range of travel or its “range of motion”. When this occurs, the force being applied downwards during activity is still being applied to the arch of your foot but now there is no more cushion effect left because the arch is at the end of its range of motion. That is, the arch is as flat as it is going to get. Now the foot will begin to get hurt and the energy of impact gets transferred upward through other joints such as your ankles, knees, hips, back and neck, resulting in pain and possibly injury.

In a perfect world, the “ideal scene” of an arch support then would be basically an orthotic arch support that would correctly support the arch by always keeping it in the center of an available range of motion and never allowing it to fully “bottom or flatten out!” Because if this were to be the case, a continued cushioning effect would always be maintained that would prevent injury to the arch of the foot and all of the joints of the body as well. Remember that injury only occurs when the arch completely flattens out and the forces from activity are transmitted to the flattened “non cushioned” foot and the rest of the bodies joints as a result.

There are multiple limitations of workability in nearly all orthotic arch supports available on the market today.

First of all, the basic shape of the orthotic shell usually doesn’t effectively duplicate the shape of the person’s arch. The result of this major limitation is that the arch isn’t uniformly supported because of the lack of “total contact”. When an arch support is not in total contact with the arch of the foot, the arch still flattens and “crashes down” onto the orthotic which is usually a more generic and subsequently lower arch shape than your foot. Conversely, a total contact orthotic arch support has the capacity to “cradle” your foot and arch smoothly from the beginning of your arch’s available range of motion and allows your foot to flex to some degree without completely flattening out! Again, pain and potential injury can result when the arch completely flattens out or if it continually slams down onto an orthotic arch support that does not correctly approximate the unique shape of your arch.

Next, many foot orthotics are constructed using a molding process made with a process similar to the way traditional “broken bone” casts are made. They are built up around the foot using white plaster impregnated bandages, again much like what was commonly used to set a broken arm or leg back in the day. Several problems with this casting method include the fact that the foot hangs out in mid air while the cast is applied, thus the captured arch shape can be very different than the shape of the foot and arch when it is actually being placed down on the ground during walking or running. To compensate for this, the manufacturer builds up the plaster “positive” in the area of the arch and the outer foot with more plaster. This leads to a very subjective “artistic” component that is added into the process and factually speaking, every bit of plaster added to the plaster impression takes it further and further away from the actual shape of the foot. This is to say that since the cast is taken in a non functional position it is no wonder that such “modifications” must be made to the orthotic molds. The result is a foot orthotic that you can usually place two, three or even four of your fingers between the arch support and your arch when you place your foot on top of your orthotic while in a seated position.

Conversely, our foot orthotics are casted using a molding method that utilizes a foam casting material that is similar to the foam sometimes used for holding artificial plants in place. Additionally, the person’s weight is partially on the foot during the casting process and it is done by placing the foot down into the foam in a series of steps very similar to how the foot strikes the ground during normal walking. The result is a totally accurate cast that provides the proper shape of the foot and arch as it will functionally act under real-world every day conditions. This casting technique is so accurate that zero “modifications” are needed or are ever used. The result of this cast is an orthotic arch support that fits perfectly into your arch and supports and controls the motion of your arch so that you never get to the point of a completely flattened out arch!

This method of a total contact orthotic arch support and having the ability to completely control and foot and arch and subsequently all of the joints in the body is not a new one. This orthotic arch support concept was attempted with very rigid and unyielding plastics and even stainless steel and very few people could benefit from the total contact style of orthotic because they could not tolerate it. The problem was that if you go total contact in the arch you MUST allow the foot to move and flex to some degree to allow the foot and body to utilize their natural shock absorbing mechanisms. These rigid materials held the foot in the correct position but did not allow normal function. Now we have the best of both worlds because of the relatively new developments in modern day plastics. These plastics can tolerate the flexing action that is required by the foot to promote normal function and shock absorption without cracking, breaking or deforming. The plastic that we use is very expensive but it gives us the ability to properly control the foot and therefore control the entire joint and skeletal system of the body.

The real trick is how to fine tune the devices to allow just enough flex and function. This is done by taking your weight, your foot’s relative flexibility and the shape of your arch into account. But when this is done properly, the result is an orthotic which is in contact with the whole arch from beginning to end of the action of the foot striking the ground. The effect is then as described above – a gentle cushioning effect preventing any excessive and destructive impact and subsequent strain on the muscles, tendons or joints of the entire body.

Cushion. The now faddish craze is increase cushion. What this does is absolutely nothing biomechanically for the person who is having these problems. All is does is to some degree dampen the shock. It supports nothing and corrects or realigns nothing. In fact, picture if cushion was all we needed to get rid of all of the orthopedic injuries in the foot, arch, heel, knee, hip, back, neck etc…, all we would have to do is put down two inch silicone cushion padding under all work surfaces. Well they tried cushion mats in the work place back in the day and they did nothing but increase injury because they made people more unstable. And even standing statically will eventually create more problems than relief in that, just like walking in the sand, the cushion will conform to you bad foot alignment which does nothing more than perpetuate the underlying cause of the problems; your arch is completely flattening out.

The cushion will immediately mask the problems to some degree which is why the Dr. Shoals (“Are you gell’en?) in the supermarkets and chain pharmacies over the entirely of this country continue to sell that crap. People go there as a first line of defense, not much differently than when they grab for the Nyquil or the Robatussin. Likewise these do nothing but suppress the symptoms until the body corrects itself but the “cushion technologies” obviously don’t cause your body to spontaneously correct its alignment and in fact, now that we have added a “bounce” component to the equation, in some people there is a greater disposition to actually cause injury.

The most recent “smart shoe” that varies the cushion effect of the heel via a computer chip in the rearfoot of the sneaker, is no more than an advanced concept of the same thing. This smart shoe will not realign the bones of the foot and will not positively affect the supra structure (ankle knee hip back etc…).

The computer casting scam. There is a method to “capture the form of the foot” by walking over a mat that reads the downward pressure created by your foot. You can walk over the mat and get a reading of your right and left foot. We have a similar system here in the office that is used for different reasons like seeing pressure points in people who don’t feel their feet etc…, but we don’t use it to “cast the foot” like some other technologies do.

More to the point is this. Even though you can definitely see the heel and the balls of your foot which give you the length of the orthotic arch support that you would need, first off you are capturing the unsupported foot that gave you the problems in the first place and since this is only a two dimensional data collection device (you only see it on the screen in 2D not 3D), how do you know where the arch began? The answer is that you don’t because all you get is the flattened out arch “computer imprint”. That is, if you take three people all with size 10 feet, and say one person’s arch starts at 4 inches and flattens to 2, and the next starts at 3 inches and flattens to 2, and the third person starts at 2 inches and flattens to two, how does this medium tell that? The answer is that is does not because it only can capture data in two dimensions. So they use a pre fab “custom fitted” orthotic shell that will never be a total contact fit for the obvious reason that they don’t ever see or capture what the original “non pathologic” position of the foot is with this method. Bells and whistles, Dog and Pony, but not good accurate methodology!