Orthotics don't work. Or they do. But we don't know why.

OK, I guess we’ve moved into the era where we can figure out that, basically, nothing works. Or, things work, but not the way that we expected and since we’ve thrown out all the old science, we have no way of quite knowing how the new science works.

Confused? So is the New York Times.

Today’s article regarding orthotics should be a political hot potato in the shoe world. Benno Nigg, a professor of biomechanics and co-director of the Human Performance Lab at the University of Calgary in Alberta, has spent 30 looking at orthotics and come to some interesting conclusions. The most interesting: Shoe inserts or orthotics may be helpful as a short-term solution, preventing injuries in some athletes. But it is not clear how to make inserts that work.

Part of the key may be the confusion of what aspects of the body the orthotics work upon. Instead of aligning the skeletal structure, as we might have supposed, Prof essor Nigg believes that they turn out to have little effect on kinematics — the actual movement of the skeleton during a run. But they can have large effects on muscles and joints, often making muscles work as much as 50 percent harder for the same movement and increasing stress on joints by a similar amount.

So does this tie in well to the cited Canadian soldiers study? Half of the 240 soldiers got inserts and the others, for comparison, did not. The findings were somewhat puzzling: While the group that used inserts had about half as many injuries — defined as pain that kept them from exercising for at least half a day — there was no obvious relation between the insert a soldier chose and his biomechanics without it.

What is funny is that, to anyone in the retail business of fitting and selling orthotics, the fact that the soldiers were able to pick inserts that they felt were comfortable had a huge effect on their efficacy. I have found, after 20+ years in retail, that most people will gravitate towards an insole that fits the shape of their foot. So it comes as no surprise that people would find insoles that fit, and that those actually had a measurable effect on their feet.

I think part of the problem is that the business of orthotics has long operated with a far greater percentage of art than science, perhaps more than most docs would want to admit. And there is plenty of anecdotal evidence, of ordinary people to Olympians who have cured a knee pain with an orthotic in a shoe, it just turns out to be more guesswork than science.

Joseph Hamill, who studies lower-limb biomechanics at the University of Massachusettsin Amherst, agrees.

“We have found many of the same results,” said Dr. Hamill, professor of kinesiology and the director of the university’s biomechanics laboratory. “I guess the main thing to note is that, as biomechanists, we really do not know how orthotics work.”

And yet, we know, that when you guess right, they do.

So how does this affect us in the shoe/orthotic industry? I have been flamed for contradicting Steve Magness in a much earlier post when he wrote that stability and motion control shoes don’t do a damn thing. My contention then, and now, is to say that: for whatever reason, we have lucked on to certain wedges under the foot that can alleviate pain. How they work, we clearly don’t know. Yet too much of our anecdotal evidence shows that they do have a positive function when used correctly for me to want to stop using them. If we can get the art part to work, then we’ll have to remain artists whenever necessary. Just artists with restraint.

In a shop like mine, where I’ve pretty much always preached a fairly conservative approach to shoes with stabilizing features or the use of Superfeet inserts, its not a real change. Although I will find myself changing what I tell the customer when I do resort to using an over the counter orthotic. For other shops, certain running speciality franchises where the clerks are supposed to be upselling the Superfeet to prescribed percentage of customers, or Le Foot in Berkeley, which has always preached motion control for all, it may be a much bigger change. Especially if the customer has been doing his/her reading of articles like this one.

So is it dishonest for me to show my customer a video of them running straighter in shoe A than shoe B, and to nudge them to wearing shoe A? My video analysis lacks scientific rigor, but I have to believe that, once we take into account what the person has been used to (there is that darn art side again), then it is easier to make the connection on how much correction we might want to put in.

It would be interesting to see how much thought has been put into seeing the foot in isolation versus at the end of a long, interconnected series of levers and pulleys. When Dr. Nigg points out that they have a huge effect upon muscles and joints, we have to wonder how many orthotists look that far up the chain? I have some brilliant podiatrists in my area and if they have a blind spot, its sometimes treating the foot in pure isolation as opposed to part of a very complex system. If a person’s knee is used to rotating inward as the arch collapses 2%, then a 2% wedge n a fairly supportive shoe can theoretically not just straighten the knee but cause an exterior rotation, or a tightening of the IT band to counteract the knee suddenly tracking differently. I’m not sure that all of that is always taken into account. (Yes, I know that there are likely going to be some who believe that by going to only minimalist or barefoot shoes, the foot will strengthen to the point where an orthotic will not be necessary, but this discussion presupposed that that is not a short term option.)

What are your thoughts?