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AgnesNitt
06-24-2010, 05:57 PM
I have bad pronation caused by a shortness in the first metatarsal (morton's foot).
I have an orthotic, custom built for skates that improves but doesn't fix the situation. The result is my blades have to be off center (but not as much off center as they were without the orthotic)

So I'm an engineer, I have an extra pair of old skates and i'm thinking of some other solutions since I have a pair of skates I can mess with. Recently I came across some Bont carbon wedges (http://www.bont.com/shop/product.asp?ItemID=812&Start=0) for 2 point inline skates. These allow you to put some angle on your blades. I've had this before (piece of leather or a washer), but with these carbon wedges I could get some serious angle. I've got some ideas for handling the 4 point figure blades vice the inline 2 point blades.

Anyone have any experience with canted blades. I mean some serious canted blades? Do they work, or after you reach a certain angle does it become problematic? I'm willing to video my experiments and make reports.

Query
06-24-2010, 07:06 PM
You could augment the orthotic by adding a little athletic tape under the inside of the foot, making the whole orthotic tilt to one side. This causes the entire boot to tilt to the desired angle, instead of just the blade. If the correction is bad enough, you might need to reshape the interior of the boot so you don't get too much excess pressure on one side.

You can also add moleskin to the inside of the boot, on the inside side, at ankle height, and add it above and below the ankle on the outside side, so differential pressure from the boot tends to force the ankle straight. Or throw away that expensive orthotic, and modify your own insole with tape to the shape you really need.

(Maybe you don't want to completely correct the pronation, if doing so makes your foot uncomfortable or unhealthy? That's a matter to discuss with your doctor.)

Offsetting and tilting the blade like you are doing may be simpler.

But when I offset my blade to much, my foot got sore. There is a certain line along which your feet support weight more comfortably than others. Making modifications inside the boot eliminated the need for the offset, in my case. But maybe the story isn't the same, because my ankle joint doesn't tend to pronate.

If the arch is collapsing too, you could add extra tape to make a bump under the arch, to prevent that. If the orthotic is rigid, you have to add the tape on top of it, instead of underneath, to change the shape, which means you might want to use moleskin, which doesn't come off as easily under abrasion.

But why do the carbon wedges let you go further than a leather shim? You could sand the leather into a wedge shape. (Sand by hand! Don't let a powered machine sander remove your finger.) I assume you already bought the carbon wedges, but I'm curious if they have some advantage.

Be careful to equalize the pressure on different parts of the mounting plate, including next to the wedge shim, whatever material you use. If not, the plate may twist and warp, which may also curve the blade. It may also gradually twist and warp the bottom of the boot. I made a mistake once, and my plate and boot started to warp. In fact, equalizing pressure on the two sides of the insole, to prevent boot warp, is a good reason to make corrections inside the boot instead of creating an offset. Klingbeil has claimed boots are often twisted and ruined by offsets.

Does what I'm saying make sense to an engineer?

What I suggest will modify the foot shape your doctor carefully modified. If you are cautious, you could ask the doctor whether the modifications are appropriate.

katz in boots
06-25-2010, 03:59 AM
Our Russian coach recommends using old credit cards to slip under blades to correct things like this. I laughed, but guess who has pieces of plastic under her right blade now !

This is not what I'd call 'serious' canting, but layers of plastic (or leather) can do the same job. Mind you, I imagine leather might compact over time, so a fairly firm material would be best.

AgnesNitt
06-27-2010, 06:43 PM
Dear Query, the orthotic is huge. It was also made with the assumption that I would be wearing it in flats, so when I put it in boots, my foot is not in the same position as the flat position the orthotic was built on and it's killing me.
I like your idea of throwing the old orthotic away and building my own. I'm looking at building a home grown two stage orthotic, one part on the heel, the other in the forefoot. My goal is to be able to skate with the blade in the center rather than offset, and use a combination of internal support and canting to get it there. I particularly agree with your experiences re off-set boots twisting the sole.
As to why I like the carbon wedges, it's because they are a fixed size and won't flatten down. I don't use moleskin although it's a good idea. I put a stiff felt couch leg tip under the rigid orthotic to get me in the right position, unfortunately that makes the high arch support even worse. However, I skate great.

For Katz in Boots. I like the idea of credit cards. I think that would be worth some testing.

I plan to test all my theories in my old boots. Get Mike to put the blade back in center, then I can tweak it inside and outside until I"m happy with it. If I ruin the boot, so what, it's trashed any way.

I did try elastic laces this weekend. They're wonderful over the forefoot, alas no support over the ankle, so coach told me to swap them out.

GoSveta
06-28-2010, 01:37 PM
Get Orthotics made for skates, and look into getting fitted by a master fitter. Also make sure that the skates you have are good for your foot type. Boots that are "perfect" for one person can be "all wrong" for another.

A Sore Achilles Tendon and a trip to the hospital for X-Rays is all it took to convince me that skate boots and shoe inserts are not necessarily a good match.

The best way to use inserts is to get the boots custom made with space alloted for them. You usually have to send the inserts in with your order to get that done.

I'm definitely flying to New York with my SuperFeet as soon as I'm ready to get new boots (and those will be customs) for a fitting there. My blades are off-center (but feel centered, for me at least!) as well :P

AgnesNitt
06-28-2010, 07:06 PM
this all may be moot for a while. I missed the step in aerobics, fell backwards and stuck my hand out to break the fall. No swelling or numbness, just pain in the wrist. Iceing aspirin and putting my wrist in the wrist guard to keep it in an neutral position until I can get to dr if pain doesn't clear up tonight. Am typing one handed. So long for a while.