Prescription Orthotics users: What brand does your Dr. prescribe?

What is the advantage of custom orthotics vs. off-the-rack orthotics?

This is the deal with foam boxes used to mold the foot for orthotics:

The whole point of orthotics are to hold your foot in a certain position. To do so, a mold of your foot must be made held in the position that the orthotic should hold it in as well. So, if you stick your foot into foam in a "screwy" position, the orthotic will ultimately hold it in that position as well. Also, regardless of how soft the foam is, it will push back upon the foot, distorting the skin and fat pad to a degree. It's nothing like your fat pad, which is your intrinsic padding of the foot, flattening out on a concrete floor, but it does distort it. Doctors use this because it is cheap and quick. Period.

The best way to get your feet molded for orthotics is to have your feet molded with plaster of Paris in a non-weight bearing position. This way, the doctor holds your foot in the position it should be in when it is standing upon the orthotic, so it's important that you ask the doctor if they do the molding themselves or if an assistant does it. The assistant, likely, will not know nuances of biomechanics to get it right - so ask before you invest your money. This mold of your foot (it's called a "negative mold", by the way) is the first step of many to make a good orthotic, and if this is done incorrectly then everything else will be incorrect as well.

As far as the further virtues of plaster of Paris, there are many. One, the plaster conforms very well to your feet, getting the most accurate impression. You can see skin lines, or "finger prints" left on the cast. Also, the foot is molded with the contour of the foot undistorted - unlike the foam molds. The value of this is that the fat pad is contained by the device, thus maintaining the intrinsic cushioning. It's not allowed to spread out as easily and thus actually has more shock absorption. Lastly, any areas on the foot that need to be offloaded can be marked on the foot, and when the plaster dries, the mark transfers over to the mold. The orthotic manufacturing lab then knows exactly where to make the necessary accommodation.

The orthotic lab used is extremely important as well. The old-fashioned way, but still the best, is to pour plaster of paris into the mold taken by the doctor. After the plaster dries, the original mold is then torn off - leaving an extremely accurate reproduction of your foot around which the orthotic materials will be molded (this is called the "positive mold"). Some labs, to save material costs, scan the inside of the negative mold and put it into a CAD (Computer Aided Design) system, which then either mills out a positive mold or directly mills out an orthotic out of a block of polypropylene. The inherent difference between a plaster "positive" and a CAD orthotic is how true the plaster one is to your original foot. I don't care if you have thousands of data points with what is essentially a topographic map of your foot with the CAD positive, it is still not more accurate than the plaster one. My contention is no corners should be cut. A lab that makes the plaster positive will charge more for the end product, but once again you will have a more predictable result.

Once you get to this point, the orthotic material, regardless of how hard it seems when you are trying to bend it in your hand, will not feel hard under your feet. An orthotic, to do its job, must be rigid to a degree, or your foot will manipulate it instead of it manipulating your foot. The final product can be made from graphite, fiberglass, graphite/fiberglass, polypropylene, layers of foam which go from high-density near the floor to low-density in contact with your foot, and a combination of cork and leather. The ones made from graphite and/or fiberglass will be thinner and thus will fit into a wider variety of shoes, but they might be too rigid for high-impact sports like running. Foam laminate ones will be better for sports, but will not likely fit into good dress shoes. They will also break down sooner and have to be replaced.

That being said, I think that one of the best orthotics on the market are Northwest Podiatry Labs. They actually specialize in graphite orthotics which are made from the plaster method. They also can make devices that vary in flexibility - so you can have a pair of orthotics that fit into your dress shoes but can also fit under the insole that comes with your shoe so it can function as a sport orthotic. You then get the best bang for your buck.

Lastly, ask the doctor to put a heel post on the orthotic. This addition is not there to raise your heel, but is stabilize the orthotic and thus better stabilize your foot.

Sorry for the long, convoluted post, but I hope this helps! Also, I have no vested interest in Northwest Labs.

Good post.

The problem with foam is that when it's pressed down a certain number of times, it stays compressed - the small cells that give the foam its compression qualities collapse down permanently. You then have an orthotic that does not have the padding, conformity to the foot, and shock absorption that it used to have. See, you want a device that changes shape just enough to allow the motions that your feet need to go through while running to occur. However, you want that device to then go back to its original shape. Foam can do that for certain amount of time before losing its shape. So can polypropylene. Polypropylene can be made into a sport orthotic as well, but after a matter of time, this plastic will want to flatten out because it originally was a flat sheet of plastic before it was molded around the positive mold of your foot. As time goes by (and the amount of time depends upon usage, activity, even the temperature of the environment) the plastic ones tend flatten out to their original flatness. You'll never get a device that's flat as a serving tray, but you get my point.

The only exception to the plastic ones that don't tend to flatten out are the ones milled via a CAD system - since they came from a plastic block. However, they do not have the flexibility qualities desirable in a sport orthotic.

That's why I like graphite orthotics made from graphite/graphite-fiberglass. A well-made one can allow the foot to go through the motions necessary for running (or any other sport - just like the foam sport ones) but they go back to their original shape for a much longer period of time than the ones mentioned above. Your feet will probably change shape before these things do.

The only caveat that I can give on the graphite ones are that they can break if you gain weight. Once again, they are made to be able to give/flex to a certain degree - so that depends upon your body weight. If you gain, say, 15-20 pounds, you can stress the orthotics beyond their capabilities and they will simply crack. A good lab, however, will have a warranty on them though. Northwest Labs have like a 1.5-2 year warranty.

With the graphite ones (or the plastic ones) you can have a top cover, or padding, put on top to provide extra cushioning. This cushioning, like foam, breaks down or bottoms-out over time. But you can easily get those things refurbished, along with the heel post stabilizer (don't forget that this is essential) and the orthotic can be as good as new for around 80-90 dollars.

Oh and Langer is OK - average. I forget if they use a plaster positive to mold the orthotic around, but their orthotics are average.

Not that I know of.


Did you take the insole that came with the shoes out before you put the orthotic in?